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69GTOby
Tribal Scout

USA
17 Posts

Posted - 26 Nov 2018 :  12:05:32 AM  Show Profile  Reply with Quote
Hello, I wanted to provide some info on my '69 GTO to get some constructive feedback. The car is rough, but functional. The engine is '70 400 that I freshened up a couple years back with new rings and bearings. It's got crappy compression killing pistons that I'm kicking myself for reusing, but they were in such good condition I didn't want to toss them. I think they were like .035 down the hole. Anyway, it's got a Holley 750 vac sec, Torker, HEI, ported #16 big valve 75cc heads, 1.65 RR, Lunati 218/218 @ .050 110 LSA .504/.504, RA 2 1/4" manifolds and 2 1/2" mandrel bent system. SCR should be around 9:1 with an atrocious quench, lol. It runs strong and has a healthy second gear chirp. I would guess around 350 HP. What do you think?

Behind it is a 2,500 stall converter, a rebuilt TH400 with a shift kit, and a 12 bolt posi 3.73 out back. I'm running 275/60/15 street tires for now on Centerlines.

I have 1 3/4" x 3" long tubes to put on which should help a lot. I had an Edelbrock Performer, but had the Torker to try and honestly, I think the open plenum is working pretty well. I had to richen up the squirter, but there is no bog now. I'm sure it gives up some torque, but it doesn't really hookup anyway. I think the HP up top is worth the trade-off in this case. I think it would benefit from more cam, maybe something with around 230 @ .050, maybe the 041 or a newer version of it, and certainly some real pistons and closer to 10:1 SCR with a decent quench.

This is just a toy. I plan to get it track worthy and blasting down the 1/4 mile on weekends. I like driving it on the street every once in a while, too. I am open to any suggestions. I will probably pull the engine eventually to swap the pistons and go thru it, but I'd also like to optimize my combination for the time being.

Corncob2061
Cochise

USA
300 Posts

Posted - 26 Nov 2018 :  10:46:27 AM  Show Profile  Reply with Quote
Sounds fun like a fun car. 350hp sound reasonable. I would not be to concerned about the quench for the time being. 9.0 is enough to make good power even without good quench. It has been my option that those pistons cause detionation from the extra edges in the valve releifs and contours in the pistons more than bad quench. Just my opinion though. I would do everything you can to get the exhuast out of the engine faster, like the headers, maybe an x or h pipe. Make sure the exh crossover is blocked off and switch to an electric choke if you have not already. I think 9 is a good place to be with those pistons.

Is it a torker 2 with a Holley?

Sounds like you reringed the engine, do you remember what it had for ring grove, maybe can give you some idea as to how much potential you have from that. That cam is not a big hp cam up in the top of the range, probably why the torker felt like an improvement. Great bottom and midrange cam though. Should be a lot of performance potential with a cam change if you wanted at some point. But sounds like it runs pretty good and is a fun ride.
Jay
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69GTOby
Tribal Scout

USA
17 Posts

Posted - 26 Nov 2018 :  12:00:08 PM  Show Profile  Reply with Quote
Thank you for your reply. By the way, I used to be a somewhat active member on the HPP forum several years ago, but that site was ruined. I would hate to see the same thing happen to this site. I never got involved here, but I would often end up on this site thru my Pontiac research. I think I'll stick around :)

Yes, not only are the pistons .035 or more down the hole, but the 20 valve reliefs add CCs and rough edges as well. I think once I get some real money, I'll put some flat tops in there and shoot for near 10:1. I may even do forged rods at that time and possibly stroke it as well. I'm dreaming, lol.

But, like you said, it's runs pretty well for now, so I'm just going to optimize what I have. IIRC, it is the original Torker, and yes a Holley with the choke removed completely. I was talked into the Lunati 218/218 for a different combo, a 350/365ci with stock #13 heads and a Performer intake. I had it in the GTO for a while while doing the 400. I pulled the 365 once I finished this 400 and I transferred the 218/218 cam from the 365 into the 400. The 218/218 cam was probably OK for the 365 combo, but even then, now that I know a little more, I don't know why an expert suggested a single pattern cam. I had stock heads which have infamously bad exhaust ports, manifolds, and full exhaust.

Even with my 400 now with ported heads and headers which I'll put on here soon, it's still running thru mufflers and tail pipes. I think a dual pattern is almost always a better choice. Look at the factory cams, even with more recent well-breathing, efficient engines, they still use dual pattern cams!

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Corncob2061
Cochise

USA
300 Posts

Posted - 26 Nov 2018 :  9:25:26 PM  Show Profile  Reply with Quote
The 1.65 rockers help the duration of the cam some, probably 270/270 222/222. Not terribly small. It is puzzling why lunati did not set the 350 up with a 262 voodoo??? Was it becuase of the 1.65s?

Sounds like you have plenty of carb.

Do you have the hei tricked out?
Jay

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69GTOby
Tribal Scout

USA
17 Posts

Posted - 27 Nov 2018 :  04:18:16 AM  Show Profile  Reply with Quote
Actually, it's 218/218 @ .050 284/284 PN 10510472, but yeah it's probably closer to 222/222 @ .050. Lunati didn't recommend it, someone else did on another forum. I agree, the 262 would've be much better, especially with my 400 I'm running now.

I have a Comp 290b-6 cam that I got from the same guy I got the ported heads and Torker from. I think it's way too big for my 400 with a stock bottom end, crappy pistons and 9:1. It's a solid flat tappet with 255/266 @ .050 290/304 .540/.540 106. I think I would need forged everything to turn 6,500 rpms and like 11:1 on 110 octane to run that thing lol.

I'm running an electronic billet distributor. It's been a while since I played with it, but I'm sure I set it up with 32-36 at around 3k and 14-16 at idle. I was running an MSD box, but it quit on me. Yeah I think it's got plenty of carb, too. I wanted to try a 700 Holley mechanical secondary carb a friend has, but never got around to it. I think the tunability would be better with 4 corner jetting and 2 squirters, particularly with the open plenum. I had to make my 750 vac sec FAT to get rid of the bog when I switched to the Torker.
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Corncob2061
Cochise

USA
300 Posts

Posted - 27 Nov 2018 :  09:51:38 AM  Show Profile  Reply with Quote
LOL, 106lsa..yikes....That would be a more than a handleful to drive on the street. But it would work great in a 400 bracket engine.

You have the better of the two 218/218 cams at least on paper. Sometimes they turn out to be the same cam though. It has the same profile as the lunati 280/290 214/224 cam. I have built a engine with the speedpro 218/218 112LSA cam and the SAE rating was 308/310. I think it would have been about the same profile as you have, the one we used probably had even less intensity. Not really much difference between any of the 218/218 cams. We were disappointed with the cams performance up in the top of the power band. Did great everywhere else though.

350 hp is probably on the low side with the 1.65 rockers, a decent set of ported heads and all your other goodies. Probably in the upper 300s with headers, especially if the cylinders are straight.
Jay

Edited by - Corncob2061 on 27 Nov 2018 10:17:26 AM
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69GTOby
Tribal Scout

USA
17 Posts

Posted - 27 Nov 2018 :  5:24:41 PM  Show Profile  Reply with Quote
Yeah, I think this engine is a little undercammed. I ordered a cam yesterday, a 284-H12 Crane from Amazon, brand new with lifters for $77. I think it was a typo, because this morning I saw the same cam/lifter kit for $216, so they corrected the price right after I placed my order. But, my order went thru for $77. I mean, I couldn't even get the lifters for that money!

Anyway, it's pretty similar to what I have now: 228/228 @.50 284/284 .480/.480 112 LSA. It's a single pattern, but I'll put the long tubes on and maybe an x-pipe with dumps after the x to eliminate all exhaust restriction. So, this cam has 10 degrees more duration @ .050, .022" more lift, and a slightly wider LSA at 112. It should be about 232 @ .050 and .528" gross valve lift with the 1.65s. That should help on the top end, and the 112 LSA should broaden the power range. I'm guessing the ramp is steeper since it has more duration @ .050 but the same rated seat duration. Unless the seat duration is measured at different lifts by the two companies. I sure wish they would standardize seat duration figures. Anyway, the old cam had a suggested power range of 1,500-5,000 and this one is 3,000-6,000 or 2,800-6,200 depending where you look. With my 2,500 stall it should flash to right about when the cam comes on and pull HARD until self-destruction, LOL. I'll probably shift it around 5,500.

I bet it'll make closer to 375 hp like you said. If I had some decent slugs in there and 10:1 SCR I bet it would be around 400 hp, maybe more. I keep the car at my house at Smith Mtn. Lake in VA. The closest track was in Forest, VA right outside Lynchburg but it closed down. I'll have to take it to Natural Bridge, Richmond, or NC for a 1/4 mile track. I really wish there was a track somewhere closer. Maybe I'll make my own track :)
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69GTOby
Tribal Scout

USA
17 Posts

Posted - 27 Nov 2018 :  6:57:16 PM  Show Profile  Reply with Quote
Summit has the 1803 cam with the EXACT same cam specs as the Crane 285-H12, only the Summit cam shows a much lower operating range of 2,400-5,400. I'm thinking the Crane operating range is based on 350 ci. The grind was maybe even developed for a 350 SBC, IDK. But, the Summit range is probably based on 400 ci, as that is the more common performance engine for Pontiac. In fact, Summit has the EXACT grind for SBC, the 1784 with a range of 2,500-6,000. I know I shouldn't get hung up on those advertised ranges. It's just interesting to me. My point is, I think the real usable range of this cam will be pretty ideal for my car.

Edited by - 69GTOby on 27 Nov 2018 7:01:40 PM
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Corncob2061
Cochise

USA
300 Posts

Posted - 28 Nov 2018 :  12:13:34 AM  Show Profile  Reply with Quote
Wow, your not fooling around, already made an order too make more power. COOL :)

Looks like a lot better cam. Should run really hard. The 228 at .050 range with the 112LSA seems to really run hard in 400s on the street. Personally I think pontiacs d ports get a bad wrap on their exhuast flow. The porting I have done on d ports the majority of the hp comes from porting on the intake, you can make big power porting the intake and leaving the exh nearly stock. There is likely more power gained from a split pattern, but cams are always a compromise somewhere. You should hit the converter harder with the single, and sounds like you have the rpm range your looking for too. Nothing wrong with a carefully picked single pattern cam imo...

You have probably already studied it, but I will mention it for newbies to cranecams line up. The new 228/228 cam is from cranecams hmv lobe family. They have one profile more gentle that the profiles appear to be the same as the Summit cams 2800,(204/214) 2801(214/224), and 2802 (224/234). Funny thing is the 284/284 218/218 Lunati came from a very similar or the same family of profile designs, LOL who copied who, or who ground both? Crane also has a very aggressive profile which is very comparible to compcams XE profiles. Then 2 more for turning lots and lots of rpms.

I agree the Summit and Crane versions sure look identical.

That is too bad your track closed. I have one 40 minutes away but it is 1/8 mile. Couple hr drive to a 1/4. Time for a new performance app on a smart phone:)

Jay

Edited by - Corncob2061 on 28 Nov 2018 01:38:12 AM
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Corncob2061
Cochise

USA
300 Posts

Posted - 28 Nov 2018 :  11:09:13 AM  Show Profile  Reply with Quote
I agree with your standardize seat number comment. The ratings are getting harder and harder to make sense of. A great example is that very popular cam that summit lists as the 214/224 .442/.465 cam. One of the first performance cams I started with was a TRW version of it. Crowers 60918 is identical. They both used the SAE seat rating (.006 at the valve or .004 with 1.5 rockers) of 288/298, and TRW, Fed molgul, and speed pro called it 280/290 advertised. Look up Lunati, they list the cam as 280/290, same as the old TRW advertised. Which lines up with that Lunati cam your running 284/284 218/218 intensity wise. Then you can go to summit, they list the cam with the same .050 and lifts as 288/298 when they list the general cam ratings. Now, look up the cam card for the same Summit cam and it says adverised duration is 272/282. LOL. It gets even more interesting, you can go over too cranes lobe profiles and find the same .050 and lifts, and they list that their profile for that cam has 270/280 at .004. Which is even more bizarre because translating that too a .006 rating the intensity is starting to rival a XE comp, which seems kind of crazy. Who knows, maybe there are a couple versions of theses cam. Maybe they are the same.

Since your dealing with a combo that is known for its difficulties for performance use on pump gas, I will mention this: The hokey cam ratings is why on every pump gas performance engine I build these days, I check where the intake closes at .009 at the valve. Then do a dynamic compression calc for that point. If I can not retard or advance the cam too the range I am looking for once I check it, I change cams. I do not pay any attention too what the seat timing for overlap and when the exhaust opens as far as measure anything. Those I am more interest in the cams asymmetry and general opening rates. Like how the rate at which the exh valve is shutting in relation to the intake opening, for how long, and what signal the piston is sending too the intake tract in relation too that. It should also be mentioned that overlap and area under the curve also plays a big factor too. A outstanding example is that 106lsa solid cam you mentioned. I do not have near enough data to pull from for running a cam like that on pump gas and projecting a good dcr. It would build a lot more cylinder pressure when it gets into its power band from all the overlap. Put that in same 106 in an aggressive roller, LOL, be prepared to run that on methanol!
Jay
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Steve C.
Chief PONTIAC

1898 Posts

Posted - 28 Nov 2018 :  11:42:27 AM  Show Profile  Reply with Quote
Here is a previous post I made sort of related to the subject....

"I had a discussion with Shane a cam designer at Crower and I asked at what tappet lift do they rate their hydraulic flat tappet cams at..... in essence he said it did not matter and suggested not much happens regarding air flow until above 1000 rpm or so anyway and then gave an explanation. And he further commented that it will vary with their different cams, they are not all the same. He actually asked, are you trying to use it for input into the "Wallace" program."

(Many of the calculators related to cams on the Wallace and other calculator sites require input with the seat duration and not the .050" duration )

Edited by - Steve C. on 28 Nov 2018 11:46:40 AM
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Corncob2061
Cochise

USA
300 Posts

Posted - 28 Nov 2018 :  2:25:36 PM  Show Profile  Reply with Quote
Definetly a relevant conversation. I agree for sure on the exhuast profile with the seat timing being fairly irrevolent. Tuning solid cams I have never been able to find hp with changing lash setting on the exhaust. Maybe someone else has. Intake has been a different story. Impacts performance a fair amount on some engines. Not an exact comparison because lash effects things across the entire profile. But lash certainly has more effect at the seat timings than up in the profile.
Jay
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69GTOby
Tribal Scout

USA
17 Posts

Posted - 28 Nov 2018 :  5:28:12 PM  Show Profile  Reply with Quote
This is very interesting stuff! I just came across the thread on this site about the 041 cam. I was intrigued because I often found that it seems like several companies have their own "version" of the 041. After reading that thread I learned that some of the discrepancies were more due to rounding, like companies rounding the 113.5 LSA up to 114, and due to different seat duration measurements. GM advertised the 041 with 308/320 seat timing, but as was pointed out on the other thread they were closer to 280/290 or whatever using the SAE seat timing at .004" at the lifter and .006" at the valve with 1.5 rockers.

I ran into that before with GM cams. I upgraded the cam in my '90 Caddy with a 350 TBI SBC. It had the tiny peanut cam and I put in the "395" GM cam found in the marine engines, the Ram Jet crate, and the HT 383 crate. It's 196/206 @.050 and 288/308 advertised. I was wondering how the hell it had so much seat duration with dump truck duration @.050, and wondering how it would play nice with TBI. Then I discovered GM does adv durations at like .002 or .003, which makes them look huge.

It's kind of cool telling how different companies produce the same cams, but advertise them differently. If they are indeed the same exact grind, but advertise seat duration figures at different lifts, it gives an idea of the profile or shape of the lobe.

I ran into that with the Wallace calculators, too. You have to use the correct figures, whether it's .050 or seat. And if the calc is meant for seat duration, it can only be close to accurate, because seat duration measurements vary from .002-.006. Who knows what the calc formula is intended for? And if the calc is meant for using duration at .050, then it's still assuming a certain adv duration and assuming a lobe profile!

I learned that all those calculators can really only be used as a guide. Whether your calculating overlap or dynamic compression or whatever, the calculators can only tell you so much. A cam with a very aggressive lobe that is promptly opening a valve and then slamming it closed might have the "same" DCR as a cam that is gradually opening and closing the valves. But, obviously the aggressive lobe will have a much higher compression. In other words, it will build much higher cylinder pressures than the other cam, which of course translates to power and potential detonation issues, albeit they have the "same" DCR on paper. DCR results can be very misleading.

I'd like to know more about the different types of lobes that are out there. As I understand it, there are the fast ramp cams, like the Voodoo series and the XE cams. Then there are the old school cams that are inherently not aggressive lobes, and probably many others in between. Jay you mentioned the HMV lobes. I am not familiar with those. I'd love to know more.

I have discovered that the more I learn about cams, the less I feel like I know, and the more I want to know!
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Corncob2061
Cochise

USA
300 Posts

Posted - 29 Nov 2018 :  01:17:23 AM  Show Profile  Reply with Quote
How much did the powerband seem to change going from the 365 to the 400 with the same cam? I am curious if the ported heads made the power band act about the same?

The rocker arm ratios show up on the seat timings on SAE rated cams because measurements are at the valve on SAE. It is by far the most most accurate rating method. Hyd roller cams are slower off the base circle than a flat tappet, it usually adds a fair amount to seat timing numbers. I thought gm switched to the SAE sometime in the 80s, but that GM 395 cam does appear to use the old GM rating system. Interesting

The 041 ra 4 is 292/303 at .006, 304/315 using the SAE, and like you said that big 308/320 is an original gm rating... all those numbers are for the same cam with different rating methods.

The HMV profile stands for Hydrualic maximum velicity. The camshaft you listed that is on order 284/284 228/228 is from that family. It is rated at .004. I do not know what the .006 rating is. Just guessing it is between 276 and to 278 if you wanted to compare it to compcams or one of the other .006 rated cams. It is an asymmetric camshaft. That is from the centerline of the profile it has less duration on the opening side and more on the closing. The HMV series is 4 degrees shorter on the opening and 4 longer on the closing. Just for comparison, a symmetric cam like the 218/218 or a 041 has the same duration the opening and closing. Versus one of the Lunati voodoo series cams which are about 8 degrees shorter on the opening and 8 longer on the closing. So the HMV cams are kind of in the middle asymmetrical wise. They have good intensity, similar to one of compcams magnum profiles in intensity from .050 to seat timing. They work good with 1.65 rocker arms and should have good valve control with pontiacs 30 degree intake seats.
Jay

Edited by - Corncob2061 on 29 Nov 2018 08:46:47 AM
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tjs44
Crazy Horse

USA
545 Posts

Posted - 29 Nov 2018 :  10:50:42 AM  Show Profile  Reply with Quote
Jay,when I was having engines built by Joe Sherman he gave me a little wisdom when we were building my 383 stoker 301 engine.I told him I wanted to shoot for 425 HP at 9.5 iron heads.He said we needed about a 230 CFM head.I had Dave at SD do a set of 15 heads with a 2.05 intake valve for the 4in bore.Daves smallest CNC program was a 260 port.Joe said the better the head the less cam needed to make a target HP.SOooo the reverse of that holds true!FWIW,Tom
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Steve C.
Chief PONTIAC

1898 Posts

Posted - 29 Nov 2018 :  11:29:49 AM  Show Profile  Reply with Quote
"The most meaningful statement you can make about power production is that it all starts with cylinder heads that can flow large quantities of air. But having the greatest flowing heads counts for zero if the valves are not opened sufficiently or at the right time in relation to the crankshaft's rotation, and that very important function falls to the camshaft."

https://www.hotrod.com/articles/0607phr-camshaft-basics/

Edited by - Steve C. on 29 Nov 2018 12:41:37 PM
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69GTOby
Tribal Scout

USA
17 Posts

Posted - 29 Nov 2018 :  12:02:16 PM  Show Profile  Reply with Quote
I did a little research on the HMV lobe yesterday and any information on it is kind of elusive. Where do you go to get deeper info on lobes like that? I'm glad the cam on order has the HMV lobe. It seems beneficial to take advantage of the "fast ramp" cams as they have a lot to offer for building cylinder pressure, i.e moving lots of air and doing what a camshaft is supposed to do for an engine. But, I'm not crazy about the idea of the XE, Voodoo and others, which as you explained have a very aggressive lobe, only because I've heard it's hard on the valve train. I'm sure valve springs fatigue sooner than they would with a less aggressive lobe and they would probably be more prone to breaking. Valve float would probably happen sooner and more severely and the camshaft slamming valves closed by nature would already be hard on the valve seats. Plus I would imagine the lobes themselves would be more sensitive to breaking in. All that is kind of the nature of a racy engine, but most of us are developing our own personal projects and don't want to shorten the life of all the expensive parts we buy. The HMV sounds pretty good to me. It's run in the middle.

Honestly, I can't really answer your question about the power band changing. I'm not sure because it's been years since I had the 365 in there. Plus, once the 400 went in I did a ton of suspension work. On top of all that, the tach hasn't been working for a while now. I just never got to do any quality back-to-back testing unfortunately. I would say that it has a strong chirp going into second and I don't think it did that before.

The #16 heads were on a 455 with the Torker, 290B-6, 1.65s... IIRC it ran 9's in the 2,300 or 2,600 lb light car it was in. I got all the go-fast parts from the guy who let his kid run the car down the track. The kid shifted it at like 7k for some stupid reason and blew it up. The short block was destroyed, but I got all the goodies for cheap. I had the heads rebuilt due to several bent valves. They rebuilder told me, "Someone spent a lot of time porting these heads!" I wish I found out if it still had the 30* seats or if they went to 45*. It was a pretty radical 455 with like 12:1 and that silly big cam, so I wouldn't be surprised if they did change the seat angles.

Tjs44, what do you mean by "383 stroker 301 engine?" Was it 383 or 301? Tell me more. I always wanted to do a short stroke build like the T/A 303. I would think that ideally the head and the cam are both designed to have the same flow characteristics. I suppose if one were more capable than the other, it would help it out to a certain point.

What exactly does the lobe asymmetry do to flow? I would think that 8* less on opening and 8* more on closing would kind of gradually accelerate the air flow... So instead of the flow kind of peaking at max valve lift, maybe it would peak a little later with the increased duration on the closing side. At least, that's how I envision it in my head.
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Steve C.
Chief PONTIAC

1898 Posts

Posted - 29 Nov 2018 :  12:07:59 PM  Show Profile  Reply with Quote
And related, we can get hung up on the cylinder head CFM ratings. We should always remember the total airflow thru the carb, intake manifold and the cylinder head ports to the engine at the piston will be the important factor. The horsepower potential is based on intake-system airflow, or the total airflow to the cylinder thru the carburetor, intake manifold and cylinder heads.

Example when Rocky Rotella and Jim Hand performed testing they found a unmodified Edelbrock Performer intake was in the 88 percent range (just like a stock intake) at 250-255 cylinder head cfm. But modified intakes with blended ports can up a stock intake to about 92 percent. If a Q-jet carb is in use and 'stock' it can reduce air flow by about another 5 percent. In some instances using a factory cylinder heads you'll need head flow in the 260 cfm range to get 240 cfm into the engine. I believe some of this related testing is in Jim's book.
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Steve C.
Chief PONTIAC

1898 Posts

Posted - 29 Nov 2018 :  12:52:15 PM  Show Profile  Reply with Quote
Opening statement made- "This is just a toy. I plan to get it track worthy and blasting down the 1/4 mile on weekends. I like driving it on the street every once in a while, too."

I don't get the impression this is a 'daily type driver' with lots of expected mileage involved, aka a "hobby car". With that in mind you maybe worrying a tad bit with this comment....

"I'm not crazy about the idea of the XE, Voodoo and others, which as you explained have a very aggressive lobe, only because I've heard it's hard on the valve train. I'm sure valve springs fatigue sooner than they would with a less aggressive lobe and they would probably be more prone to breaking. Valve float would probably happen sooner and more severely and the camshaft slamming valves closed by nature would already be hard on the valve seats. Plus I would imagine the lobes themselves would be more sensitive to breaking in. All that is kind of the nature of a racy engine, but most of us are developing our own personal projects and don't want to shorten the life of all the expensive parts we buy."

Example, do the searching and read about UltraDyne lobes designed by Harold Brookshire (also the designer of Voodoo lobes) that have closing rates not much more 'aggressive' than original GM factory cams.
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Cobrabill
Talking Dog

Aruba
3155 Posts

Posted - 29 Nov 2018 :  4:26:40 PM  Show Profile  Reply with Quote
Don't trust your "butt dyno"-dump the Torker and get all your timing in by 2500.


Edited by - Cobrabill on 29 Nov 2018 4:30:27 PM
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69GTOby
Tribal Scout

USA
17 Posts

Posted - 29 Nov 2018 :  5:59:24 PM  Show Profile  Reply with Quote
LOL Steve as I was writing that about the aggressive lobes, I realized how I was kind of contradicting myself. I think I'm a little conservative and stubborn in general and it leaks into my car world. This is definitely NOT a daily driver. In any case, I couldn't pass up the new Crane 228/228 cam with lifters for $77 or whatever it was. What a deal! I suppose I could even perhaps buy a more suitable cam, just the cam, and use the lifters I get with the Crane cam...

The Torker, which I'm second guessing myself now and need to confirm that that is indeed what I have, has an adv operating range of 2,500-6,000 IIRC. That is perfect with my 2,500 stall and new cam, isn't it? My thinking is that with all my hardware coming on around 2,500 as opposed to the stock 1,600 or whatever it is, that I can take advantage of the benefits of that Torker at higher RPMs. I'm thinking it really shines above 4k over a dual plenum. But, IDK I haven't done any testing to reinforce my speculation. It is probably better over the Performer I have, but perhaps a Performer RPM would offer the most "area under the curve."

I definitely need to do some more tuning. I plan to weld some bungs into those headers before sticking them on so I can actually see the AF ratio. Of course, once I swap the cams I'll really have to do some tuning anyway. I'll definitely bring in the timing as soon as I can without diminishing returns. It'd be nice to have full timing at 2,500 right around when that converter hits.

I think I may have to get some slicks! Haha
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tjs44
Crazy Horse

USA
545 Posts

Posted - 29 Nov 2018 :  9:33:21 PM  Show Profile  Reply with Quote
here is the 301 stoker build
http://forums.maxperformanceinc.com/forums/showthread.php?t=710524
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69GTOby
Tribal Scout

USA
17 Posts

Posted - 29 Nov 2018 :  10:10:38 PM  Show Profile  Reply with Quote
I LOVE it! I always wanted to build something like the 303 built for T/A racing in 1970. The 301 that went into production was based off that racing 303 engine. I'm sure you know that already. I always thought the 301 was inherently too weak to make any power with. Everything else would be no problem - bolt on big Pontiac heads, fab a sheet metal intake or cut down an aluminum one like you did. I just didn't think the block would ever survive.

I actually got a 301 for free on CL years ago. I was going to rebuild it, but it needed lots of machine work because she was TIRED. I just couldn't justify putting all that money into a 301 when I had a 400 in my GTO that needed help. I still have it tho. It's an '80 or '81 T block. Actually I think they were all T blocks in 80 and 81. Anyway, you've inspired me. I'll hang onto it and one day maybe build my dream '77 or '78 Trans Am the way Pontiac would have built it if there weren't so many emissions restrictions and red tape at the time. I can't wait to peruse thru that whole thread on your build.

Oh and I came across this thread: http://psp.aquacomp.net/topic.asp?TOPIC_ID=1248
Wow, I was in high school when that thread was going on! You guys are probably wondering why the hell the topic keeps coming up. I'm running the Torker because I want to even tho my engine apparently doesn't want me to, LOL. Actually my only alternative right now is a Performer. I wonder if the Performer with a little work and a spacer could rival the RPM manifold. I had 2 cast iron 4 barrel intakes and STUPIDLY practically gave them away.
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Corncob2061
Cochise

USA
300 Posts

Posted - 30 Nov 2018 :  11:04:27 AM  Show Profile  Reply with Quote
Do your heads have stock sizes intake ports? i.e. stock intake gaskets vs ra 4 size?

With the 8 valve releif pistons that torker might not be all bad. Shuffling some performance from the bottom end to the top is not a bad idea if the engine is a little detionation prone. Only one way to find out.. No doubt there are better intakes.

Tom does have a cool 301 build. One of a kind.

Cam profile info is hard too find. Best resource on that stuff I have is called Steve C. :)

Asymmetric cams basically shift the area of the curve over so that more of the area is being used to fill the cylinder, and less is used for scavaging when the intake first opens. It helps manage the cams overlap by making the cams profile smaller as the valve is being opened, which helps idle and mid range by decreasing the reversion in the intake air (caused becuase the intake and exhuast valves are both open and the piston is headed for TDC). It allows the engine to run more overlap without loosing idle and mid range power.
Jay
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tjs44
Crazy Horse

USA
545 Posts

Posted - 30 Nov 2018 :  11:07:34 AM  Show Profile  Reply with Quote
I have built 2 303 RA V stroker engines also,one a 366 and one a 389.Just sold a 366 NASCAR RA V std deck engine.Building now a RA V std deck 440ish engine with a factory 2-4 Xram with a pair of EFI throttle bodies.Waiting for the stuff to get here before 100% sure of the induction.Tom
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69GTOby
Tribal Scout

USA
17 Posts

Posted - 30 Nov 2018 :  12:17:29 PM  Show Profile  Reply with Quote
Jay, honestly, I couldn't tell you if it has stock sized intake ports or RA IV sized. I suspect they're stock sized or I would've noticed when I put it together. I bet since the Torker and these #16s were mated together on that racy 455 that they are port matched. I'm sure I used some stock style gaskets, and I don't remember trimming the gasket ports to match... I'm anxious to take it apart.

That's a good point on the Torker staving off too much cylinder pressure given these crappy slugs. An RPM intake is on the docket for future upgrades, along with flat tops, rods, and maybe a whole stroker rotating assy. I bet these heads are capable of 450 hp or so on a 400 with with the right CR, cam, and some RPM capability.

This is kind of irrelevant, but I had an ear break off of the block when I was dismounting it from the engine stand. Thus, the engine is mated to the trans bell housing with one less bolt than it should. Is this a problem, or a potential future problem? I'm sure they designed it with 6 bolts for a reason...

Is there a way to turn this stuff into a career? If I could do something in this field professionally, I think I could be truly happy. I got tired of working on boring, modern cars everyday and moved on to construction earlier this year. It's been pretty good to me and I see loads of potential in the new field, but it's still now what I REALLY want to do. Tom, it sounds like maybe you found a way to have your passion-hobby for a career. Are you hiring?? HAHA
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Steve C.
Chief PONTIAC

1898 Posts

Posted - 30 Nov 2018 :  4:43:59 PM  Show Profile  Reply with Quote
Not apples-to-apples with the potential 400 combination here and a larger cubic inch Pontiac, BUT.....

Avg horsepower from 2,500 rpm to horsepower peak with a Pontiac dual-plane intake Vs Torker II intake. The Torker II was down only 2 horsepower. Point being don't always count out a Torker II intake with the idea that you always need that bottom end. But as always it will be combination specific. But also look at the torque involved not just horsepower.

"Even though the Torker II and Holley made our Trans Am feel much more powerful and its 467 showed a 15-rwhp increase, not every combination can benefit from the addition of a single-plane manifold. That doesn't remotely suggest that the Torker II or any other similar dual-plane, for that matter is a bad choice."

https://www.hotrod.com/articles/hppp-1112-dyno-testing-intake-manifolds-and-carburetors/



Edited by - Steve C. on 30 Nov 2018 4:49:41 PM
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Steve C.
Chief PONTIAC

1898 Posts

Posted - 30 Nov 2018 :  5:08:55 PM  Show Profile  Reply with Quote
"Edelbrock's Torker II is a single-plane manifold that features a relatively small plenum with long, narrow runners that provide strong mixture velocity. The result is the ability to mimic dual-plane performance at lower speeds while maintaining excellent high-speed performance. The plenum volume is a bit small for larger engines."

Rocky Rotella


Edited by - Steve C. on 30 Nov 2018 5:09:52 PM
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Cobrabill
Talking Dog

Aruba
3155 Posts

Posted - 02 Dec 2018 :  1:33:18 PM  Show Profile  Reply with Quote
Performer is no better and sometimes worse than a factory cast iron. RPM is the superior piece. And notice that no factory engine came with a single plane manifold.Screw posted magazine articles.

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Steve C.
Chief PONTIAC

1898 Posts

Posted - 02 Dec 2018 :  1:50:03 PM  Show Profile  Reply with Quote
The Edelbrock Performer intake isn't even being considered for the 400 cid combo being discussed here.
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Steve C.
Chief PONTIAC

1898 Posts

Posted - 02 Dec 2018 :  2:31:21 PM  Show Profile  Reply with Quote
Oh the hatred for published material :)

Not a recommendation here, but just a tid bit for conversation. From a old High Performance Pontiac magazine which did a test between the stock Pontiac intake & the Performer intake, and the results at the track after 5 passes or something like that was that they both performed the same (due to runner design/velocity etc.).

Jim Hand testing...

The results are presented as (gained) or (lost) in reference to the stock cast iron manifold. With it, the wagon ran in the range of 12.5 to 12.75 at 107 to 109.

* Edelbrock Performer No change in ET or MPH

http://www.dapa.org/building-a-strong-street-machine-part-14-intake-manifold-tests/

On other similar testing mentioned with different combos involving how much loss in ET and MPH with the Performer vs the modified factory intake. Use the reported numbers, including the race weight of the vehicle involved, from that testing then use the formulas to see how much is lost in power. Probably not enough to lose sleep over on a street only combo !

Just remember it's combination specific.

ONWARD THRU THE FOG


.

Edited by - Steve C. on 02 Dec 2018 2:34:21 PM
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Corncob2061
Cochise

USA
300 Posts

Posted - 03 Dec 2018 :  11:52:40 AM  Show Profile  Reply with Quote
I would think if they would have port matched the intake to the heads when they were porting. Sounds like you have the stock intake port size. The original torker power band estimate was kind of a joke. In spite of how it was rated the original torker did not do much until 4000 . They also have not been made for 20 some years.

You can definetly do port work on performer. I am pretty sure the testing Steve mentioned from the Jim Hand intake testing it was port matched with his engine. It was not something that was just purchased and through on the engine. If your willing to put in the time for port work it can be a good street intake. RPM is hard to beat big hp and tq with a carb, torker 2 is hard to beat with fi on the street.

There are some Resto shops you would probably enjoy working at. There is one not far from me the owner gave me the tour of his cars and projects last year. They had a plymouth cuda stripped down only the paint was done, the car was up on a rotisorie. No engine, drive line, suspension, fenders and front end, glass, interior, dash, completely striped. Two months later I saw the car at a good guys car show. My jaw dropped. Took some serious man power too do that.
Jay

Edited by - Corncob2061 on 03 Dec 2018 12:14:54 PM
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Steve C.
Chief PONTIAC

1898 Posts

Posted - 03 Dec 2018 :  1:01:08 PM  Show Profile  Reply with Quote
I spaced the word 'Torker' in the first post here and just presumed it was the improved Torker II in use. Sorry for any confusion.

Again not a recommendation, but....

When you read where people test the Performer intake we know the obvious, to consider the combination involved. One example, a fairly aggressive hydraulic roller cam in use in conjunction with a higher peak power RPM involved in a 455 along with a modified factory intake, which certainly isn't well suited to a Performer as cast with small port volumes.

One thing about a Performer, you have to port match them....they are cast with very small ports and really aren't suitable to run out of the box. Again in the opinion of many for a street engine with a small to middle of the road cam, then a port matched Performer would be fine....no better than a good factory 4 barrel manifold, and a LOT lighter.

Edited by - Steve C. on 03 Dec 2018 1:17:03 PM
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Cobrabill
Talking Dog

Aruba
3155 Posts

Posted - 03 Dec 2018 :  2:24:20 PM  Show Profile  Reply with Quote
quote:
Originally posted by Steve C.

The Edelbrock Performer intake isn't even being considered for the 400 cid combo being discussed here.

So what?

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Corncob2061
Cochise

USA
300 Posts

Posted - 03 Dec 2018 :  2:45:15 PM  Show Profile  Reply with Quote
https://m.youtube.com/watch?v=Sy_VzDlSies


:)

Edited by - Corncob2061 on 03 Dec 2018 2:47:06 PM
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Steve C.
Chief PONTIAC

1898 Posts

Posted - 03 Dec 2018 :  3:09:05 PM  Show Profile  Reply with Quote
Bill, again excuse any confusion here but I made that comment because I didn't think the Performer intake was even considered here for this application. I first mentioned the Performer intake only in conjunction with my point about a intake manifolds effect on total system air flow to the engine. I made reference to Jim Hand and Rocky Rotella testing of that intake only to serve my point.

Edited by - Steve C. on 03 Dec 2018 5:32:36 PM
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Corncob2061
Cochise

USA
300 Posts

Posted - 04 Dec 2018 :  1:30:19 PM  Show Profile  Reply with Quote
A fairly common race mod on those old torkers was to spend some time grinding to open up the plenum and round the edges on the top sides of where the air enters the individual runners. Back ports do not take much work, but a lot of grinding can be done on the front runners. Then they usually ran a spacer on top to help utilize those mods. It was a popular mod for drag car engines. Knowone to my knowledge has ever had much luck making that intake run with a dual plane on the street. But on drag cars they could run pretty good. I have an old torker that was ran on a 69 GTO ram air 4 car. Ports were enlarged for the ra4, heat crossover was completely removed and has some of the plenum mods.

I am sure several of us on here have an old torker up on the shelve out in the shop. LOL, I sent the one I have out on a solid cam motor 20 years ago, last summer it shows up again.
Jay
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69GTOby
Tribal Scout

USA
17 Posts

Posted - 04 Dec 2018 :  9:31:32 PM  Show Profile  Reply with Quote
It sounds like the Torker has its place every once in a while, but that 90% of these old Pontiacs would do better with the stock unit or an RPM. My cams showed up, but I'd really like to do some testing with my current setup before swapping it in. Of course, I don't really have a good way to do that with the nearest track being closed down and the closest alternatives being over 100 miles away... That's sad. I think I might find a good stretch of road and clock my 0-60 and 0-100 times and take some objective notes and conditions and car behavior.
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Corncob2061
Cochise

USA
300 Posts

Posted - 05 Dec 2018 :  01:21:00 AM  Show Profile  Reply with Quote
Baselines are helpful. With limited traction, never know, you might find the single plane is faster.

I have enjoyed all the single plane intake street cars I have had. The way a car pulls on the street and reacts too a drag strip are sometime two different things. But that does not make the way it pulls on the street any less fun.
Jay

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Steve C.
Chief PONTIAC

1898 Posts

Posted - 05 Dec 2018 :  10:21:38 AM  Show Profile  Reply with Quote
You might also consider a chassis dyno.
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tjs44
Crazy Horse

USA
545 Posts

Posted - 05 Dec 2018 :  11:34:47 AM  Show Profile  Reply with Quote
My experience with single planes on the street with low RPM driving is the AFRs are less consistent than a dual plane.My 69 bird has had 2 diff engines in it,366 RA V and a 455 stealth RA III.Both used 780 holleys.The 455 had a HST dominator and the 366 had a McCarty single 4.FWIW
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69GTOby
Tribal Scout

USA
17 Posts

Posted - 05 Dec 2018 :  8:18:13 PM  Show Profile  Reply with Quote
My cousin has a chassis dyno, but his shop is all the way up in Martinsburg, WV and my car is down in Southern VA.

I found this CL ad and the guy is like 20 minutes away from me: https://frederick.craigslist.org/pts/d/bop-buick-olds-pontiac-engines/6757771661.html

Check out the 7th picture. It's a Pontiac with what look like finned aluminum valve covers. I saved the pic to blow it up and it's really hard to make out but the head #s look like 092 which should belong to a '66 389 orrrrr 421!
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tjs44
Crazy Horse

USA
545 Posts

Posted - 05 Dec 2018 :  8:28:14 PM  Show Profile  Reply with Quote
092s are really not a good performance head.Early valve angle,small valves and pressed studs without guide plates.FWIW,Tom
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69GTOby
Tribal Scout

USA
17 Posts

Posted - 05 Dec 2018 :  9:51:23 PM  Show Profile  Reply with Quote
I didn't know about the early valve angle and pressed in studs, but I did know the valves were a little smaller. In any case, if it's a 421, my ported #15s would sure do well on top. The extra cubes due to the longer stroke would be pretty sweet, plus I think they had a forged aluminum crank. Is that correct? Plus the asking price is... drum roll please... $250. I mean it might be a 389 or something else for that matter, but it could be worth checking out.
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cortcomp
Coyote

USA
5443 Posts

Posted - 05 Dec 2018 :  10:02:42 PM  Show Profile  Visit cortcomp's Homepage  Reply with Quote
I didn't think anything had an aluminum crank?
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tjs44
Crazy Horse

USA
545 Posts

Posted - 05 Dec 2018 :  10:04:31 PM  Show Profile  Reply with Quote
LOL,ONLY 421 SDs got a forged crank and that was 62-63,all other are cast.Tom
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69GTOby
Tribal Scout

USA
17 Posts

Posted - 06 Dec 2018 :  10:48:02 AM  Show Profile  Reply with Quote
LOL sorry I meant forged steel crank and forged aluminum pistons... I was suspicious as to whether that was only the SD that got the forged crank.

I would still think the "regular" 421 would potentially be a good performance piece. The long stroke Pontiacs are really hard to find these days - 421, 428, 455. Of course, I'd be lucky if the engine even was a 421. It could very well be a 389 or anything else for that matter with 092s and an early Carter style 4 barrel intake on it...
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Corncob2061
Cochise

USA
300 Posts

Posted - 06 Dec 2018 :  11:13:27 AM  Show Profile  Reply with Quote
It would have an arma steel crank from the factory in 66. Which is a cast crank with some different alloys in it than the later cranks. IRC, Arma was the name of the foundry. Pretty difficult crank to find in a 4 inch if your searching for one. Most likely a 389. We have a 66 389 2bbl with those heads out of a 66 star chief. Definetly a find if it ended up being a 421 imo.
Jay
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69GTOby
Tribal Scout

USA
17 Posts

Posted - 06 Dec 2018 :  11:23:08 PM  Show Profile  Reply with Quote
I always wondered why they were called "arma" steel. I'll have to go look at this guy's pile of junk engines to see if there are any real gems. There are at least 3 Pontiacs I can see in the pics. The 4 barrel is the 1 in question, an early either 389 or a 421 by the looks of it. The other 2 are 2 barrels and probably nothing special...

There are a few 4 barrel Olds engines in the heap. I wonder if there's a 403 in there. I always thought a 403 would be cool. I know this is a Pontiac forum, but the Olds was found in our beloved T/A afterall :). I know they were inherently weak, but they are good for 400-450 hp according to some magazine write-ups. I like the enormous bore and relatively short stroke of the 403. It's different. There looks to be a 283 or 327 2 barrel in there as well. That would certainly do well in my '52 Chevy in place of the old worn out Stovebolt 216.
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tjs44
Crazy Horse

USA
545 Posts

Posted - 07 Dec 2018 :  11:24:44 AM  Show Profile  Reply with Quote
ALL 421s are 4 bolt main blocks.You can tell a non 389-400 block as there is a transfer lug on the rear pass side of the block.Tom
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