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 Low-budget, Low-Compression, Low-Lift 455 project
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Lee
Sitting Bull

165 Posts

Posted - 18 Dec 2017 :  3:33:49 PM  Show Profile  Visit Lee's Homepage  Reply with Quote
I've been hot rodding for close to 40 years now, drag racing for over 30, and been around Pontiacs for virtually my entire life (I'm 51, btw). One trend I've seen getting worse (IMHO) is pushing "race" type parts and builds on people who are really needing "solid, reliable street" builds.

Granted, most of Pontiacs have been street/strip builds, and have been heavily tilted towards the race end. But my current budget and needs for my "new" Pontiac ('73 Firebird, cloned into a Trans Am) are directing me towards a path less travelled.

My wife enjoys riding in this car. I first installed a set of Year One 17" Rally II wheels. Next I updated the A/C with a Sanden compressor, parallel flow condenser, 134a spec POA and expansion valve, so I can cruise comfortably in the Texas summer heat.

Last year, I picked up a $500 455 cont.

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com

Lee
Sitting Bull

165 Posts

Posted - 18 Dec 2017 :  4:07:08 PM  Show Profile  Visit Lee's Homepage  Reply with Quote
The $500 455 turned out to be a complete engine, carb to pan and some accessories. It also included a THM 400, extra starter motor, and a few other things! The seller stated that the engine had been rebuilt up north, where his brother lived, then they shipped the car down here. It started and ran o.k., but "blew oil everywhere" when driven on the highway. I knew I'd need to take it apart, but did not then have a clear plan for what I was going to do with it.

Upon teardown I found the valley pan gasket was mis-installed, with a 1" gap for crankcase pressure (and oil) to blow out of. I also found the ring gaps were WAY bigger than they should have been - up to 0.150" gap on some that I measured! The camshaft was a CompCam 268, the old single-pattern design with .454" valve lift. The cam and lifters were in perfect shape, so I knew the valvesprings were well matched to this sort of cam. I still did not have a clear plan for the motor, though.

Meanwhile, the old 350 Pontiac was still running smoothly in the car, I just had a bad taste in my mouth from having something that LOOKED like a '73 Trans Am, but only had a 350 in it! I put it on my chassis dyno before I did anything to the motor, and it put a whopping 160-something HP to the wheels! I played around with the timing and carb, and got "up" to about 185rwhp - better, but still rather sad.

By last summer, I was ready to get the 455 installed. I cc'ed the heads (# 66's) and was sad at the HUGE chambers. My pistons were all (on average) 0.022" down the hole, and the pistons have the chamfered edges making the CR even lower. Compression calculated to a bit over 7.8:1! Even worse, the heads had pressed in rocker studs.

I WANT a set of heads from Dave Bischopp, and I also want an IAII block with about 535 inches, but those are still not in the budget... Hmmm, maybe do something different?

cont.

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com
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Lee
Sitting Bull

165 Posts

Posted - 18 Dec 2017 :  4:24:29 PM  Show Profile  Visit Lee's Homepage  Reply with Quote
I've been designing custom cams for a long time, and started using some engine modeling software several years ago. With the software, I've designed some very different, yet VERY effective cam designs for LS engines. I've also used it for several Pontiac cams that have ran very well. So I decided to see what sort of design it would show best for a much milder motor.

With high compression ratios, you have to worry about creating too much dynamic compression, causing the engine to experience detonation. But with only 7.8:1, I don't have that limitation. I didn't want to mess with the heads, and also worried about the pressed-in studs - since the previous cam had been fine with .454" valve lift, I decided I would use LESS lift so that no changes would be needed.

I ended up with 222/242 @ .050" lift duration, .443/.435 valve lift, 116 LSA and installed at a 112 degree ICL, custom ground by Bullet Cams. Look all you wish, you won't find anything like it in any catalog!

I installed new rings on the existing pistons, did a quickie home-hone job on the cylinders, new rod bearings, and a new oil pump. I used the Performer intake and Q-jet that had been on the 350, along with the HEI and log exhaust manifolds from the 350. I had to richen the idle mixture screws a bit, but otherwise it ran fairly well.

The exhaust system had the stock head pipes coming off the manifolds, then 2.5" pipe sloppily welded to the old head pipes and feeding into 3" Flowmaster mufflers, with another sloppy transition into 2.25" tailpipes (which rattle annoyingly at idle).

Back on the chassis, I was at 220rwhp right off the bat. Playing with timing and metering rods got me to 225hp at about 4,000rpm. Peak TQ reading was 310, but that is a bit misleading as I couldn't go to full throttle below around 3500rpm, or else the transmission would downshift.

cont.

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com

Edited by - Lee on 18 Dec 2017 8:06:51 PM
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Lee
Sitting Bull

165 Posts

Posted - 18 Dec 2017 :  4:50:48 PM  Show Profile  Visit Lee's Homepage  Reply with Quote
I had picked up a set of killer headers from forum member Steve Coombes. I got those headers with the intentions of a big HP motor with the Dave B. heads, not a low-compression stock headed budget motor. As time arrived to saw off the old headpipes and install headers, I got cold feet :-)

BIG primary pipes, reduced ground clearance,... Hmmm... I made some calls and sent some messages, and located a set of Tribal tri-Y's that were built and ready to ship - I bought them.

I had to cut the "ears" off of my transmission, in order to install them. Once that was done, they went on rather easily. I used the ARP header bolts with the extra-small 5/16" socket head, to make it easier to get a wrench on all of them (NOTE: get the 1" long bolts, the 3/4" bolts will only have about 3-threads that engage).

I am planning on replacing the pipes and mufflers, but wanted to see what sort of difference JUST the headers would make. I used some parts-store reducers to connect the 3" collectors to the 2.5" pipes, tacking it all together with my wire-feed welder while laying on my back (ugly welds, but it works!).

Although there were some exhaust leaks when I started it, it sounded better. Driving it around, if seemed to feel stronger - but I've learned over the decades that most butt-dyno's are poorly calibrated.

I finally got it back on the chassis dyno. First pull, no changes to the carb, and it put 265hp to the wheels! Power band was higher everywhere, and pulled to a higher rpm as well. Richened the carb with some thinner metering rods, and got 270rwhp and 345tq. So 45hp and 35tq improvements, when looking at peak values. More telling about the improvement of the header, however, was at 4500 rpm the motor was making 55ft-lb more torque than with the manifolds!

Even with the stock torque converter, traction is very limited and throttle response is immediate. The motor runs fine on the cheapest gasoline I can find. I've been driving fairly often recently, and it is very reliable. I'm using 3qt.s of CompCams 15W-50 break-in oil (high zinc) mixed with 3qt. of 20W-50 conventional Castrol, and the low-lift mild lobes should give me long life for the cam and lifters.

I'm scheduled to have my exhaust guru install all 3" pipe and Borla mufflers next week. I believe I will find even more power with those parts in place. A FAST XFI Sportsman efi system will be installed after the exhaust is done.

Will I break into the 300+rwhp zone??? I also plan on testing some different intake manifolds as well, after the EFI system is sorted out. Then, sometime next year, I hope to get it to the track and see what it will do :-)

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com

Edited by - Lee on 18 Dec 2017 8:13:25 PM
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Maurice Hood
Tribal Scout

USA
6 Posts

Posted - 18 Dec 2017 :  6:45:56 PM  Show Profile  Reply with Quote
Lee, I enjoyed reading about the buildup of your Firebird. Well written and informative, keep the information coming.
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Blued and Painted
Chief PONTIAC

USA
3481 Posts

Posted - 19 Dec 2017 :  11:17:22 AM  Show Profile  Reply with Quote
Subscribe !!


Bull Nose Formula/ 461/ Q-Jet/
TH400/ 3.08 8.5 / R44TS.
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ta man
Two Feathers

Canada
42 Posts

Posted - 19 Dec 2017 :  2:33:33 PM  Show Profile  Reply with Quote
Good stuff...I agree ..I often see over built street car build ups for guys who just want to cruise.I'm trying to steer my son in that path. He sees my car SD heads hyd roller cam fuel system..etc.
I tell him you have to start at the basics..and with our Pontiacs basic is pretty good.I'm trying to teach him what can be interchanged rather cheaply..instead of the "Stroker/Aluminum head/Roller Cam mentality.

I should have taken my old 76 455 4 speed to the track with under 8 for compression it was rather impressive just with headers and a good 2.5 inch exhaust system.

1980 Trans Am
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Lee
Sitting Bull

165 Posts

Posted - 19 Dec 2017 :  5:45:37 PM  Show Profile  Visit Lee's Homepage  Reply with Quote
Thanks guys :-)

There used to be a summary of how my old '67 Firebird went from running 12.3's to running 11.2's using the same heads, shortblock, headers, intake, and carb. I don't remember where I posted it, or where it went to. Maybe I can keep this project documented on here. Maybe I can eventually catch up to TA Man ;-)

Oh, my EFI system shipped today 8-D

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com
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Phil
The Great White Buffalo

USA
7250 Posts

Posted - 20 Dec 2017 :  09:24:05 AM  Show Profile  Reply with Quote
Nice thread Lee. If the spirit moves you, perhaps you would consider doing a separate thread for the AC work as it could be quite useful to some of us wanting to keep AC but needing to do some sensible upgrades. I know I have a 74 which will definitely keep AC but needs some work on the system and a 79 and 80 as possible candidates down the road as well.

Bowties are for Pee-wee Herman. "Chevy": even the name sounds cheap, but not as cheap as your Pontiac will be with an LS transplant.

Edited by - Phil on 20 Dec 2017 09:25:43 AM
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ta man
Two Feathers

Canada
42 Posts

Posted - 20 Dec 2017 :  10:15:32 PM  Show Profile  Reply with Quote
Lee one thing I've always enjoyed in this hobby is watching others tune their combination of parts.Over a span of 6 years I did something similar went from low 12's 114mph to 11.0's 123mph,same heads,intake,carb,cam ,exhaust,convertor..Its amazing what one learns in the process.Plus its all out there for others to learn.I know for sure Jim Hand influenced my way of thinking and tuning..

1980 Trans Am
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Bill Boyle
Horse Feathers (Charter Member)

USA
4958 Posts

Posted - 21 Dec 2017 :  04:58:06 AM  Show Profile  Visit Bill Boyle's Homepage  Reply with Quote
Jim Hand's influence on the Pontiac community and hobby is stupendous.

"Dedicated to keeping the classic Pontiac engine alive."

----
400 bored +.030, forged TRW pistons, ported 62 heads, Hedman headers, 2.5 SS dual exhaust X Pypes, Comp 276AH10 cam, Scorpion 1.65 RR, 850 Q-jet, stock intake & tuned HEI; original owner.
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phil400
Crazy Horse

Canada
503 Posts

Posted - 21 Dec 2017 :  07:42:47 AM  Show Profile  Reply with Quote
I?m very much enjoying this thread, and this way of thinking, not everyone has 6-10k to spend on an engine. And parts availablility can be an issue for others. Working with what ya got, great Idea.

78T/A 4-SPEED Marty blue 400/milled 6x-4's/268H,comp roller tip rockers/ performer Q-jet/RA manifolds 2.25" exhaust with x-pipe/ mine since '99 3rd & final owner as long as I'm alive.
77 T/A sold
85 Monte Carlo SS sold
83 Mustang GT sold
"Let me tell you what Melba toast is packing"
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Lee
Sitting Bull

165 Posts

Posted - 21 Dec 2017 :  10:09:50 AM  Show Profile  Visit Lee's Homepage  Reply with Quote
quote:
Originally posted by ta man

I know for sure Jim Hand influenced my way of thinking and tuning..



I'm rather proud to be able to say that I was one of the first people to recognize who Jim Hand was, when he started posting on the internet a bit over 20 years ago :-)

Just a few days ago, I was cleaning up my office. In with some of my reference binders was a manila envelope, sent to me from Jim Hand in 1997. He had analyzed my Firebird's engine combination with his engine modeling software (I currently use a newer version of the same software) and offered suggestions to further improve my performance.

Heck, if anyone has read the Popular HotRodding article on my old Falcon wagon, I specifically mention Jim's influence in the write up! Even though I was building a Ford, I was using thoughts on torque, gearing, and overall powerband that I had learned from playing with Pontiacs and discussing things with Jim.

Phil, thanks! In all honesty, I COULD pull money out of savings or just carry some credit card debt and build the $10k engine that I REALLY want in the car. But I make a little money off of selling cams, dyno tuning, and other such "car stuff" and my goal is to keep this hobby "cost neutral."

I've now hit 270rwhp, and am a bit surprised! So, no I'm committed to this project :-) The new exhaust goes on next week (if my exhaust guy has time, he is retired and does this stuff out of his house now). The new EFI system should be delivered later today, but I'll wait until I have the exhaust on and have dyno tested it - I'm really trying to show the power gains (or lack thereof) with each change.

I have ideas for a few other dyno tests as well, but those will be down the road

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com
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NOTROD
Two Feathers

USA
71 Posts

Posted - 23 Dec 2017 :  11:46:29 AM  Show Profile  Reply with Quote
Great thread! Reminds me of the hours spent years ago scouring the salvage yards looking for carbs, intakes, heads, distributors, etc. Catalogs where only used for hot cams, headers and such.
I totally understand your "butt dyno" poor calibration comment, but with a street only build the "butt dyno" is all that matters if you ask me. A person can spend a grand to pick up a few tenths at the track and the car will feel no different on the street. In some case it might even feel slower.
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Lee
Sitting Bull

165 Posts

Posted - 23 Dec 2017 :  11:57:32 AM  Show Profile  Visit Lee's Homepage  Reply with Quote
quote:
Originally posted by NOTROD

Great thread! Reminds me of the hours spent years ago scouring the salvage yards looking for carbs, intakes, heads, distributors, etc. Catalogs where only used for hot cams, headers and such.
I totally understand your "butt dyno" poor calibration comment, but with a street only build the "butt dyno" is all that matters if you ask me. A person can spend a grand to pick up a few tenths at the track and the car will feel no different on the street. In some case it might even feel slower.



I have a great example of that! Back in '05 I had grown tired of my 3" Flowmasters. They were old when I got the car, and I had it for 10 years at that point. I talked with Tom Hand, and he sent me a set of large-case Goerlich Xlerator mufflers. There were a bit too big, so my part of the deal was to cut sections out of the case and weld-in patches so that they would fit the car. I also took pictures and sent them and test data back to Tom.

Those mufflers made the car WAAAYYY quieter! Shockingly more quiet. Just the noise reduction made me "sure" that I must have lost at least 20hp. First trip to the track with the new mufflers, and the car ran nearly a tenth quicker and over a full MPH faster!

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com
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Matt H
Cochise

USA
322 Posts

Posted - 03 Jan 2018 :  11:44:53 PM  Show Profile  Visit Matt H's Homepage  Reply with Quote
Lee- I am on board with your project. I just finished reading what you have done and am interested to see where you go with this. Interesting to say that the headers a huge bang for the buck ...40 rwhp. Impressive. Also how restrictive the log manifolds are.

1993 Firehawk # 118 sold after 7 yrs 309 rwhp / 342 rwtq
1979 Trans Am 400 4speed sold after 17 yrs -completly restored to is former glory by the new owner / then sold for big $$$$$
1981 Trans Am Turbo Pace Car 461 Stroker with iron heads - current car

Matt H

Edited by - Matt H on 03 Jan 2018 11:54:05 PM
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Lee
Sitting Bull

165 Posts

Posted - 04 Jan 2018 :  09:21:21 AM  Show Profile  Visit Lee's Homepage  Reply with Quote
Thanks Matt :-) I believe the rwhp gain is even more impressive, if you think of it in terms of percentage. Basically a 20% gain.

I was incorrect in 3rd post at the top. The tailpipes were actually just 2.0"! With the car on the lift at the muffler shop, I got a better view of everything. My muffler guy had to order some parts to get the system they way he wanted, so I don't have it back yet. But I'm VERY anxious to get it back and on the dyno!

My FAST Sportsman XFI EFI system is quietly waiting to be installed. After I dyno the new exhaust system, I'll start on the EFI install.

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com
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Lee
Sitting Bull

165 Posts

Posted - 08 Feb 2018 :  7:01:21 PM  Show Profile  Visit Lee's Homepage  Reply with Quote
FINALLY, everything came together, and I got to dyno the new exhaust system!

The new system is all 3", H-pipe, Borla ProXS mufflers, mandrel bent 3" tailpipes provided by Steve C., and modified by my installed for a very nice fit.

Results summary:
- Peak RWHP gain 14.44
- Peak RWTQ gain almost 9
- HP gain at 4500 rpm ~17
- TQ gain at 4500 rpm ~ 20

Here is the dyno graph comparing the old exhaust vs. new exhaust



Power gains increased proportionally to RPM. This system should be overkill for a motor at this level, yet it STILL provided power gains across the powerband. It should be fine for my future improvements.

EFI installation will be starting very soon :-)

Oh, here is a graph showing the current combo (headers and new exhaust) compared to the log manifolds and old exhaust system:


CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com

Edited by - Lee on 09 Feb 2018 2:09:11 PM
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tjs44
Cochise

USA
452 Posts

Posted - 08 Feb 2018 :  7:22:15 PM  Show Profile  Reply with Quote
Lee,im 73 and have been doing the pontiac deal since 1962.I have to ask,if this is going to be a street driver that will virtually be used off idle to 3K,is the juice worth the squeeze IYO for headers,3 in exhaust etc?Im building a fresh 421 for my 62 GP as I type.I have gone backwards.068 cam,96 heads on a 63 421 HO block,long branch, STOCK factory type exhaust and maybe a tripower or 2-4s just for some eye candy.Tom
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Lee
Sitting Bull

165 Posts

Posted - 08 Feb 2018 :  9:01:17 PM  Show Profile  Visit Lee's Homepage  Reply with Quote
Tom,

Just on the way home, merging into traffic, I hit 4000rpm. At this point, my HP is peaking around 4400-4500. I have an automatic, so can't really get a good reading below about 3500rpm, or else the tranny will downshift. Since I started with the manifolds to now, the idle has improved, off-idle has improved, part-throttle has improved. It runs better everywhere, under all conditions.

Also keep in mind that I design my own cams. This cam was designed from the onset to work best with a low-restriction exhaust system. That may play into the reason I've seen such dramatic gains. Also note that, like you, I'm running a rather non-aggressive cam. I wasn't looking to make the fastest car, but I did want to see how much power I could get out of a very mild, very inexpensive engine.

That said, I do plan to eventually make it much wilder. Most (maybe all) of the exhaust will support a lot more power. I'm about to install and EFI/ignition system that cost more than I have in the engine, headers and exhaust combined!

For me, it is worth the squeeze :-)

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com
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Lee
Sitting Bull

165 Posts

Posted - 09 Feb 2018 :  2:13:57 PM  Show Profile  Visit Lee's Homepage  Reply with Quote
I've added some dyno graphs to my post above.

Before I get asked, I've had to start easing into the dyno pulls to keep my transmission from downshifting. So the first few hundred RPM of the pull are NOT accurately representing the power. That is, the old combo is not actually making more power at lower RPM. Rather, I could floor the car at 3200rpm on the dyno with the old combo without down shifting. Now I have to be several hundred RPM higher to avoid a downshift.

FYI, when the car downshifts on the dyno it screws up all the data for the run. It is nice to have a manual transmission for dyno testing, as you can really check the entire powerband.

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com
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Lee
Sitting Bull

165 Posts

Posted - 24 Feb 2018 :  10:04:23 AM  Show Profile  Visit Lee's Homepage  Reply with Quote
EFI installation has started! FAST XFI Sportsman throttle body, with DualSync distributor. Dyno results will probably be a couple weeks from now.

Until then, here are HP and TQ graphs showing the improvements from when I first got this car until the last dyno pull.

- Bottom line is when I first got it, no tuning, low compression Pontiac 350.
- Next line up is after I did some tuning to the motor.
- Middle is the low-budget low-CR 455, using the 350's exhaust, intake, ignition (only changed the long block).
- Next up is with the Tri-Y headers installed.
- Top is Tri-Y's and new 3" exhaust.



and torque

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com

Edited by - Lee on 24 Feb 2018 10:11:36 AM
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Corncob2061
Two Feathers

USA
55 Posts

Posted - 27 Feb 2018 :  09:19:15 AM  Show Profile  Reply with Quote
Did you pick the wide centerline cam because you had always planned on the adding the fuel injection? I hope do a retro fuel injection in the near future, doesn?t appear that most hydrualic cams have enough lobe separation, which likely means custom ground cam. Even 112 is considered wide.

Interesting when you mention the Hands. I use to drag race down it the Kansas City race track and got to see Jim Hands station wagon go down the track, it seems like I may have even got to race him once. Can remember it very well cause i mainly looked at his tail lights. Late ninety?s

Look forward to your results!

Jay

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Lee
Sitting Bull

165 Posts

Posted - 27 Feb 2018 :  10:44:14 AM  Show Profile  Visit Lee's Homepage  Reply with Quote
Jay, the fuel injection had no bearing on the centerline. The software I have been using for several years to develop LS cams said that was the LSA I needed to get the overall performance I was looking for, whether carb or EFI. Effectively, some of my LSA is "eaten" by the much larger exhaust lobe - that is, I have the same overlap as a cam with a much smaller exhaust lobe and less LSA.

The old wive's tale about EFI needing wide LSA was more applicable for older, less sophisticated and harder to tune systems, and also for emissions. Basically it was to reduce overlap and make the vacuum signal more stable. Maybe it is still somewhat true for the simpler "self tuning" (FITech, Sniper, EZ) systems, but if you have enough vacuum for power brakes then those systems will work decently regardless of the LSA. But with engines with more sophisticated, highly tunable EFI computers (like what GM used on LS engines, the FAST XFI, etc.) I've found that they can handle more radical cam designs than what could be realistically used with motor using conventional carb/distributor. You can tune the better systems to run in open-loop at idle (which makes the vacuum signal meaningless) then go into closed-loop once you are off-idle (where the vacuum is more steady)

I delivered a cam for a fuel injected LS motor a few weeks ago, and it was ground on a 107LSA! It IS a radical build, and not a daily driver, but the EFI will work fine with it.

Jay, since you have a history of racing, let me ask you a question. Are you the type who drives to the track with a log book, timing light, jet kit, squirter kit, etc. and liked to tinker and tune to get the most performance out of your motor as possible? Or, the type that has/had a decent running car and kept it simple, making casual runs and not getting stressed & dirty?

I don't want to you answer that on here, but to consider those questions when you buy your EFI system. At this time, the "self learning" systems are all rather easy to get running. Most of them can be ready to go down the track within an hour or so of when you first get the system running. The better versions give you a few extra variables that you can tune, which is fun, but there are a lot of variables that are locked into the computer and you can not alter.

In contrast, the NON self-learning systems can be VERY intimidating. But, those systems allow you to do tuning things that few people ever could do with a carb/distributor. I got my system started yesterday, and I honestly felt overwhelmed at all the different tables that I can access for fine tuning! I'll need a few weeks to get comfortable with it, then I'll do a write-up.

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com
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Corncob2061
Two Feathers

USA
55 Posts

Posted - 27 Feb 2018 :  12:24:15 PM  Show Profile  Reply with Quote
Sounds like you already have a lot of experience with fuel injection, which will be handy in the weeks to come on your project. I can see how the open loop idle would make it tolerate more cam. Which is good to know. Thanks for the info. I have an engineering background, the tables sound fun. And scarry
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Lee
Sitting Bull

165 Posts

Posted - 27 Feb 2018 :  1:05:48 PM  Show Profile  Visit Lee's Homepage  Reply with Quote
Jay, with your racing and engineering background, I urge you to look into the better EFI systems. You'll both have more fun playing with the system AND end up with a better running motor.

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com
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Matt H
Cochise

USA
322 Posts

Posted - 04 Mar 2018 :  09:36:15 AM  Show Profile  Visit Matt H's Homepage  Reply with Quote
I am curious to see the EFI results. I am am looking into that set up for my 461. Really for driveability and if I pick up a few hp along the way that's great.
I am running a Holley 770 cfm carb right now that I had bought used. It runs very well but don't feel the full potential with my current set up has been reached.
I think a larger cfm carb with mechanical secondaries would be the ticket. With a new carb in the 600-700 dollar range why not spend another 400 bucks on a
EFI system.
I watched a show recently where they put a EFI system on a basically beautiful stock 78 Bandit TA and the results in driveability were fantastic. Unfortunately they did not do a dyno test but raved about the throttle response. I could see myself doing that. The installation appeared very easy. I would think the tuning would be pretty simple to as this was a self learning system. I think the newer EFIs are fairly user friendly from what I have read and seen. I think there pretty cool and can see this as a next purchase for my engine instead of a carb. Also with EFI if I ever went with EHeads and bigger cam the EFI would be able to be tuned to that set up. No need to go buy another carb. See already saving money. Lol.
Glad your doing this Lee and thanks for posting what you have found out so far. I have seen more and more old muscle cars lately with EFI at local car shows and at the track. Its the way to go from what I have seen. Look forward to the EFI results.

Matt H

Edited by - Matt H on 04 Mar 2018 09:44:42 AM
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Lee
Sitting Bull

165 Posts

Posted - 04 Mar 2018 :  4:23:39 PM  Show Profile  Visit Lee's Homepage  Reply with Quote
Matt, thanks!

A few years ago, I installed the FAST EZ 2.0 system on an El Camino. The Elky had an Edelbrock 1406 carb on it, and I did a LOT of tuning on it, using a wideband and the chassis dyno. From when I started, the Elky gained close to 30rwhp with carb and timing tuning, and I was pretty confident that it was about as good as it was going to be with that carb. So then, I installed the EZ 2.0. system.

I had expected little to no power gains, but noticeable MPG gains. It turned out the opposite, as it picked up 16rwhp, but MPG's only improved marginally. But cold start, cold driving, throttle response, ability to run CHEAP gas,... all of those aspects improved noticeably!

My current EFI project is progressing, but I hit a couple of snags. FAST left out the CTS (coolant temp sensor), and I had one in the garage that I thought would work - only after getting the car started did I realize the sensor said it was 27 degrees F outside, when it was nearly 80! After notifying FAST, they had a replacement to me in 2 days. The next snag was totally my fault. I tried to use a pump with PWM control, and it just is NOT compatible for PWM use. I had been told it wasn't, but had to see for myself. I should have a proper pump next week.

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com
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Matt H
Cochise

USA
322 Posts

Posted - 05 Mar 2018 :  11:36:14 PM  Show Profile  Visit Matt H's Homepage  Reply with Quote
Lee
The EFI install on the 78 TA was on V8 TV. Actually watched it on youtube. It was the FAST EZ 2.0 Thats pretty nice the El Camino EFI picked up 16rwhp.I would not think it would be that much. I have seen comparisons, carb vs EFI. Carbs usually come out on top under full throttle.
Not saying thats the case all the time obviously the El Camino picked up 16rwhp. I would not expect a gain with a 461 in the MPGs lol. If it picked up any at all I would be suprised. Throttle response is what i would be looking for. I talked to a guy that had a FAST EFI 2.0 on his 454 Chevelle at a local car show. He raved about it. Real pleased said it was one of the best modifications he ever did to the engine. He told me if you can afford it do it. He said he would never buy a carb again.

1993 Firehawk # 118 sold after 7 yrs 309 rwhp / 342 rwtq
1979 Trans Am 400 4speed sold after 17 yrs -completly restored to is former glory by the new owner / then sold for big $$$$$
1981 Trans Am Turbo Pace Car 461 Stroker with iron heads - current car

Matt H

Edited by - Matt H on 05 Mar 2018 11:37:51 PM
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Lee
Sitting Bull

165 Posts

Posted - 06 Mar 2018 :  09:39:50 AM  Show Profile  Visit Lee's Homepage  Reply with Quote
Matt, I installed an EZ 2.0/DualSync on a friend's '68 Firebird Convertible, mild 455 & 200-4R, about 20 months ago. He had the old Powerjection (the early version of FITech) on it, but it had quirks and never performed liked he wanted. He has been very happy with the new system. He drove from Houston to Mississippi for Cruising the Coast last fall, and said he was getting over 17mpg on the highway.


CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com
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phil400
Crazy Horse

Canada
503 Posts

Posted - 09 Mar 2018 :  09:25:14 AM  Show Profile  Reply with Quote
Lee, been meanong to ask you, do those Tri-Y headers interfere with the reverse lock out linkage?

78T/A 4-SPEED Marty blue 400/milled 6x-4's/268H,comp roller tip rockers/ performer Q-jet/RA manifolds 2.25" exhaust with x-pipe/ mine since '99 3rd & final owner as long as I'm alive.
77 T/A sold
85 Monte Carlo SS sold
83 Mustang GT sold
"Let me tell you what Melba toast is packing"
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Lee
Sitting Bull

165 Posts

Posted - 09 Mar 2018 :  12:49:39 PM  Show Profile  Visit Lee's Homepage  Reply with Quote
Phil, that linkage was gone when I got the car. Sorry, but I do not know the answer :-/

CURRENT: '73 T/A clone, starting to get less boring!...
67 Firebird (sold) 11.27 @ 119.6 Feb. '05 issue HPP
69 Falcon wagon, 10.51 @ 130mph Feb. '10 issue PHR (sold)
72 Cutlass Convertible, first car, owned since '82, now with a 6.0 LS, mild, putting just under 400 hp/tq to the wheels.
www.LNLPD.com
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phil400
Crazy Horse

Canada
503 Posts

Posted - 09 Mar 2018 :  7:25:13 PM  Show Profile  Reply with Quote
Ok no worries

78T/A 4-SPEED Marty blue 400/milled 6x-4's/268H,comp roller tip rockers/ performer Q-jet/RA manifolds 2.25" exhaust with x-pipe/ mine since '99 3rd & final owner as long as I'm alive.
77 T/A sold
85 Monte Carlo SS sold
83 Mustang GT sold
"Let me tell you what Melba toast is packing"
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