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 New guy with some 455 "plans" cam and budget
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back2class
Tribal Scout

9 Posts

Posted - 13 Jun 2017 :  11:23:48 PM  Show Profile  Reply with Quote
i everyone. First post here.

So I have this 1975 455 that is going in a 69 Tempest with 350 trans. Unknow torque converter and unknown rear end..but may end up swapping that around as this is a old project car. VERY low budget! have some questions.

Got the 455 from a guy I trust. He said it had low miles and ran well. I got it to replace the very questionable hunk of metal that came with the car..a junkyard special 400. Took the 455 partly apart the other day and clearly has had a very recent rebuild. Bores and bearings look great. .030 flat top pistons that look factory.,,,,, just one small notch on each side for valve and no chamfer edge. Heads are 6x8 (101cc) from a 400 and look like they have not been shaved. Deck height is .018-19 on all jugs, stock rods. Valves may be stock, but int and exh are for sure different steel recipies. Came with 800 Qjet and unknown 4 pipe headers. Should be a real life Static CR of about 9:0 CR best I can guess. May zero deck the block. Hate taking the pistons out as I'm sure the rigs are well seated and not good practice..but in my experience you can get away with pulling pistons and putting them back in the same hole....just would rather not.

After weeks of reading here and other forums, as well as talking to Lunati and Comp. I have pretty much decided either xe274h or 60903 for the cam. Both of these have been proven well and tested on setups very similar to mine displacement and CR wise. No point in rebuilding this thing because it's so nice and because it's a beer money build. My thinking is to just drop in one of those cams and matching springs...leaving the rest of the parts stock. Ill likely do a quick clean up on the ports and some port matching..but not a real porting job. This will be a fun weekend cruiser...not raced or ragged past 6k.

Sorry for the long post. Guess the questions I have and can't seem to find concrete answers for are;

1) WIll just upgrading the cam and springs work okay, or am I missing something?
2) Even if it all works, is this really asking for trouble?
3) One of the Mfg's said their springs were dual coil and easy drop in..no machine work with the highest lift on these cams .504. Anyone know of a drop in single coil setup that would work on these cams?

Thanks so much.

Steve C.
Crazy Horse

1675 Posts

Posted - 14 Jun 2017 :  09:01:50 AM  Show Profile  Reply with Quote
I would suggest a dual spring. The Crower 68404 is very popular and used as a 'stock replacement' spring.

If not already done so take the time and actually measure the combustion chamber volume. They are not always as published. Same with the piston dish (relief).

.

Edited by - Steve C. on 14 Jun 2017 09:03:35 AM
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Blued and Painted
Chief PONTIAC

USA
3406 Posts

Posted - 14 Jun 2017 :  09:34:35 AM  Show Profile  Reply with Quote
Many reports of annoying valve train noise with the XE fast ramp lobes.


Bull Nose Formula/ 461/ Q-Jet/
TH400/ 3.08 8.5 / R44TS.
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Steve C.
Crazy Horse

1675 Posts

Posted - 14 Jun 2017 :  09:36:37 AM  Show Profile  Reply with Quote
One method to cc a piston when it's installed.

Use Play-Doh. Make an impression of the piston dome, let it harden. Then make an opposite impression in some fresh Play-Doh. Measure the volume in the depression made in your mold. If no dome then use Play-Doh in the relief. Let it harden. Then measure how much volume it takes up.


.

Edited by - Steve C. on 14 Jun 2017 09:38:58 AM
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Steve C.
Crazy Horse

1675 Posts

Posted - 14 Jun 2017 :  09:53:05 AM  Show Profile  Reply with Quote
I will retract my suggestion here for the Crower 68404 valve spring for use in conjunction with the Comp XE lobe or the Lunati Voodoo lobe being considered here. Not enough pressure.

Sorry for the confusion.

.


Edited by - Steve C. on 14 Jun 2017 09:54:13 AM
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back2class
Tribal Scout

9 Posts

Posted - 14 Jun 2017 :  7:21:46 PM  Show Profile  Reply with Quote
Hey everyone.Thanks for the help. Appreciate it a lot!

I checked the spring specs on the ones that Lunati suggested. 120lb at installed height of 1.65 319 @ 1.10 CompCams suggested springs are 115lbs at installed height of 1.7" and 335lb at 1.15". The Ones Steve suggested and retracted from Crower are 113@1.60", 263@1.15" and 282@1.10". That is a pretty good difference on open. Interesting to note that the cam from Comp is a little less overall height on max lift than the Voo-Doo, yet Comp still calls for a slightly heavier spring? Guess it's not exact science and they pick their available product that fits best. Both manufactures suggestions are pretty similar though in spring rates.

I did measure the deck height above the pistons. But now will CC the pistons. Having done some medical work, can tell that if the only addition the pistons are contributing the CC's it's going to be small..like 2-3cc's per piston. At least going by my memory. I have not looked at them in a few days. Not near as much aluminum removed as some pistons for the 455 I have seen pics of! May have to break out the playdough to check clearance too! Thanks for that tip!

So, I am getting all sorts of conflicting info on static CR. Kept reading how 101cc heads should be about 9:0 Static on a 463. But Wallace calc says 9:6 with my measured deck height of .019 and 5cc of valve relief (calculator's default is 6.6CC's). With the default 6.6CC's, its still coming in at 9:47. But I have no idea what "gasket bore diameter" is, and left that ZERO. I will have to really check, and not go with the published 101cc measurement for my heads! Are these under "ideal" conditions, or in a real life broken in engine, are these calculator projections a little higher than real life? I was planning to deck the head to zero, but think I will save the hassle and expense. If zero deck bumps me to the 9:8 with 6.66 relief pistons and a WHOPPING 9:94 with the -5cc piston figure. Assuming these figures are right, I should avoid the Zero deck, or if I do, play with some unshrouding of the valves in the chamber I keep hearing about maybe?????.. My brain hurts!!

Edited by - back2class on 14 Jun 2017 8:57:24 PM
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back2class
Tribal Scout

9 Posts

Posted - 15 Jun 2017 :  11:04:44 AM  Show Profile  Reply with Quote
Oh, and a followup too Steve C. I keep reading that some engine builders don't like running over 300lbs with flat tappet hyd cam setups for fear of it being too harsh on the lobes. The Lunati suggested ones are @ 319lbs open and Crower 282lbs at the same open. It's tempting to play engineer and shim the Crower ones a tiny bit and split the difference. Just wish I could find a single coil drop in spring that would give around 110lbs on installed and 300ish on open. Anyone know of such a beast? I spoke to Crower and they said they "thought" the 68484 springs would be fine with the Lunati cam. But trust the guys here more for this. The Crower guy said he had a single coil that would work, but float when it got near 6k..#68305...but compaired to the Lunati is 84lbs v 120 at installed height. 285lb v 319lb open. Guess that low installed pressure is why he said they would float @6k.

Edited by - back2class on 15 Jun 2017 11:11:57 AM
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Steve C.
Crazy Horse

1675 Posts

Posted - 15 Jun 2017 :  2:56:16 PM  Show Profile  Reply with Quote
XE lobes and Voodoo lobes are different as night and day. Paul Carter has had a lot of experience with the Voodoo lobes. A fwiw, he recommends 130 lbs seat pressure (depending on 30 or 45 degree seats on the valves) using their hydraulic flat tappet lobes. And keep in mind Comp uses their 995 spring as a generic recommendation, some will suggest 120-125 for a XE flat tappet lobe (application specific). Also be very aware valve springs will lose a bit of pressure after run in and with use, keep that in mind.

If interested, contact information:

Paul Carter
Carter Cryogenics
www.cartercryo.com
520-409-7236
Koerner Racing Engines
520-294-5758


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Edited by - Steve C. on 15 Jun 2017 2:57:34 PM
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68bird
Sitting Bull

USA
221 Posts

Posted - 15 Jun 2017 :  6:11:25 PM  Show Profile  Reply with Quote
I love the power and responsiveness from my XE274, but I wouldn't go that route again simply because of the sewing machine valve train noise. I've adjusted the rockers numerous times and just can't get it to quiet down as much as I'd like. It's a hard noise to describe and I can only really hear it at idle from the roller rockers. If I was to do it over I'd probably look at the voodoo line or a full roller. Just my 2 cents

Robb Hermes
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Steve C.
Crazy Horse

1675 Posts

Posted - 15 Jun 2017 :  7:57:56 PM  Show Profile  Reply with Quote
The Comp XE lobes have a different closing rate that leads to the sewing machine sound. Both the UltraDyne and Voodoo lobes are quiet compared.
Following Harold's cam design logic they keep seating velocities no greater than most stock cams. This makes for less noise, and improved valve train stability at high rpm's as well.

I've posted Harold Brookshire's comments on why, he designed both. I'll see if I can dig them up.

Edited by - Steve C. on 15 Jun 2017 8:01:21 PM
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cortcomp
Coyote

USA
5335 Posts

Posted - 15 Jun 2017 :  9:08:53 PM  Show Profile  Visit cortcomp's Homepage  Reply with Quote
I was a fan of the numbers my XE284 put up, but hated the clacking. I just did an SBC with a lunati voodoo cam grind recommended by harold on a forum post several years back. No valvetrain noise, put up 280hp/315tq all under 5500 on a very stockish, mid to low 9's compression 327 with a full exhaust and rams horns. If i built another iron under 5k mid compression 455 like i did with the XE284, i'd find the similar lunati grind. I wouldn't mind giving up a couple horses to get rid of the noise. (That engine put up ~430hp/500ft lbs, all under 5500 because i had the wrong springs and pretty rich. I dialed in the fuel and got the correct springs, but i didn't get it back to the dyno.)

Edited by - cortcomp on 15 Jun 2017 9:09:21 PM
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Steve C.
Crazy Horse

1675 Posts

Posted - 15 Jun 2017 :  9:17:26 PM  Show Profile  Reply with Quote
This seems to be a basic street build and presumed with heads that have no port work done to them. An opinion to throw out for conversation here... to keep it simple consider a cam design with a less aggressive lobe design like the Crower 60243 then step back to the valve springs I mentioned. It would be a similar .050 duration as the XE274 with 228/235 at .050 and .479/.494 valve lift ground with a 112 lobe separation. With unported heads a little less valve lift would not be a big factor. The only 'draw back', and I use the term loosely, would be the additional seat timing and wider lobe separation with the Crower cam in conjunction with a low compression ratio (which really hasn't been verified yet).
With low compression less seat timing (advertised duration) and a 110 lobe separation would be helpful there based my understanding.

Again, just some thoughts for conversation around the coffee table.

.






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back2class
Tribal Scout

9 Posts

Posted - 16 Jun 2017 :  11:04:05 AM  Show Profile  Reply with Quote
Thanks for more great and helpful info. Will have too consider that 60243. Heads will get up to 4hrs of porting..lol. Just cleaning up the tunnel to valve seat transition, massaging the rough edges and flash in the ports and pockets. But can't see me spending the time to truly reshape the ports. Will port match with gaskets too. From what I have read, 6x heads are on the better end of stock heads flow wise. I have also read that basic cleaning up of the ports like I am planning makes a pretty good difference for the smallish time investment. Will run stock intake from a 1974 and the 800 Qjet.

Basically, what you are saying Steve is that the bigger Voodoo cam with the max lift of .505 lift is all show and no go on stock heads that simply can supply the air to take advantage of that higher lift? Again, coffee table discussion. Plus all the future readers of this thread may find it useful.

Have to travel for a few weeks, but will formally CC the heads and pistons when I get back. Assuming it comes in as expected, I'm on the borderline of "safe" CR I think. Is it "worth" zero decking the heads, then removing the same material via bowl contouring or piston relief to get back to the CR I would have started with it I just left the .019 deck height I have? Same CR/different deck height and lots of work...is a zero deck worth the effort?
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Steve C.
Crazy Horse

1675 Posts

Posted - 16 Jun 2017 :  2:20:28 PM  Show Profile  Reply with Quote
"Basically, what you are saying Steve is that the bigger Voodoo cam with the max lift of .505 lift is all show and no go on stock heads that simply can supply the air to take advantage of that higher lift?"

Absolutely not.

Here is some information published by David Vizard that some might find of interest:

VALVE LIFT.
"A 2-valve cylinder head typically continues to flow more air up to lift values equal to as much as 0.35-0.4 times the valve diameter. The reason for this is that there is a flow pattern transition period that takes place at a lift value of about 0.25 of the valve's diameter. When this point is passed, If the port has been modified to support flow in this lift region, the valve efficiency actually starts to increase. This is the reason why a 2-valve engine responds to high lift." "If you want to build a street motor with the most power without a sacrifice of idle and low speed qualities, then lift is the most important factor to maximize, not duration. The best street cams are those that seek to maximize lift while only adding a minimal amount of duration."

Bottom line, the engine wants all the lift it can and thrives on it so run as much as mechanically achievable or prohibitive because of cost limitations (such as in a solid roller cam). Obviously if it's a street application or race application will have a bearing on the situation, most here would be hesitant to run 0.700 lift on the street.






Edited by - Steve C. on 16 Jun 2017 2:22:15 PM
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back2class
Tribal Scout

9 Posts

Posted - 18 Jun 2017 :  7:12:38 PM  Show Profile  Reply with Quote
Thank you guys. Will measure it all when I get back home and make some final decisions. This helps a bunch.
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Brian R
Crazy Horse

USA
1672 Posts

Posted - 21 Jun 2017 :  1:34:49 PM  Show Profile  Reply with Quote
Just to add to what others have said, my xe274 runs well but the noise has driven me nuts for years now.

I will someday pull it for a Lunati or Crower. The only reason I have not yet is that other things have taken precedence. No amount of adjustment stops it. At idle, I HATE the sound of my 461. Drives me nuts. NEVER AGAIN will I use an XE.

Good luck with it.

Edited by - Brian R on 21 Jun 2017 1:35:55 PM
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Lee
Sitting Bull

101 Posts

Posted - 27 Jun 2017 :  4:22:28 PM  Show Profile  Visit Lee's Homepage  Reply with Quote
With ported heads and roller cams, I design my cams to have as much lift as I can reasonably fit.

But when running HFT cams with unported heads, I back off on the lift. I look at it as a ratio, failure risk to performance gain. An aggressive lobe XE or VooDoo may make 15 or 20hp more than a similar but lower-lift cam - but only until the lobe starts to wear.

Unfortunately there are not that many lower-lift HFT on the shelfs, most will have to be custom ordered, and that will cost a bit more.

If a person is so inclined, find the .050 and LSA/ICL specs for the XE/VooDoo that they are interested in. Then go to http://bulletcams.com/ and look at their master lists of cam lobes. Say I was considering an XE274, 230/236 @ .050 on a 110lsa, 106 ICL, 0.488 int./0.491 exh lift. I could order a custom Bullet with H282/288 intake lobe and H286/300B exhaust lobe. .050 specs would still be 230/236, LSA and ICL would be whatever I wanted them to be, but the valve lift would just be .432"/.450" Bullet has a KILLER selection of lobes, and I could tweak that same design to use even milder lobes or a bit more aggressive.

I just installed a custom HFT from Bullet in a low (7.8:1) CR 455 with unported heads. It is a 224/244 @ .050" on a 116 LSA, .443/.435 valve lift. I just had a surgery that is delaying final tuning and testing, but so far the motor is much stronger than I expected, and is going to require more traction than it currently has.

CURRENT: '73 T/A clone, boring at the moment...
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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Steve C.
Crazy Horse

1675 Posts

Posted - 27 Jun 2017 :  8:59:23 PM  Show Profile  Reply with Quote
If interested, a sort of Voodoo recommendation thread...

http://forums.maxperformanceinc.com/forums/showthread.php?t=777721&highlight=704+cam+beast

.












Edited by - Steve C. on 27 Jun 2017 9:00:16 PM
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back2class
Tribal Scout

9 Posts

Posted - 29 Jun 2017 :  4:16:31 PM  Show Profile  Reply with Quote
That's a great article. Lee, is the voodoo "aggressive lobed" ? I keep reading they are fairly mild and not really hard on the valvetrain. But I suppose that is subjective. I'm really torn on what to do with this great condition daily driver type engine. Maybe just sell it and take a 400 I have that is standard bore, but needs a rebuilding I have sitting here and put a rotating assembly in that one and build a better mousetrap. A nice condition 455 with fresh paint and gaskets I assume would make someone happy and fetch enough $$ to offset maybe 1/2 the cost of the parts for the 400. I keep reading all these posts about bad stock rods, broken valves and springs. It's so tempting to spend $400 on cam and springs..clean the ports, install fresh gaskets and have $1,000 total into at 400hp engine including the price of the engine itself. That or about 3k into the 400. My gut says run the risk for $1,000...I won't loose sleep over it if it blows up and spending an extra $2,000 to prevent a "possible" failure has me on the fence.
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Lee
Sitting Bull

101 Posts

Posted - 30 Jun 2017 :  2:24:25 PM  Show Profile  Visit Lee's Homepage  Reply with Quote
quote:
Originally posted by back2class

Lee, is the voodoo "aggressive lobed" ? I keep reading they are fairly mild and not really hard on the valvetrain. But I suppose that is subjective. I'm really torn on what to do with this great condition daily driver type engine. Maybe just sell it and take a 400 I have that is standard bore, but needs a rebuilding I have sitting here and put a rotating assembly in that one and build a better mousetrap. A nice condition 455 with fresh paint and gaskets I assume would make someone happy and fetch enough $$ to offset maybe 1/2 the cost of the parts for the 400. I keep reading all these posts about bad stock rods, broken valves and springs. It's so tempting to spend $400 on cam and springs..clean the ports, install fresh gaskets and have $1,000 total into at 400hp engine including the price of the engine itself. That or about 3k into the 400. My gut says run the risk for $1,000...I won't loose sleep over it if it blows up and spending an extra $2,000 to prevent a "possible" failure has me on the fence.



The VooDoo's were designed by Harold Brookshire, who also previous owned UltraDyne (and you can get UltraDyne lobes from Bullet). Harold was an extraordinary lobe designer, with understanding about rates of change of acceleration that was brilliant. His lobe designs are aggressive, designed to maximize airflow, but tempered to make them about them the less-likely to fail of the aggressive designs.

They are still more likely to fail that a more moderate lobe, though. Generally speaking, for a given .050" duration spec, the greater the lift the more aggressive the lobe design (with the exception being some race-only "max lift dwell" designs).

Milder designs can use lighter spring pressures, which will enhance lobe/lifter life as well.

Personally, I just installed a rather mild lobe design camshaft in my personal low-budget 455. Like you have mentioned, I'm hoping to get it running well and sorted out, then selling it to help fund building a more radical motor.

CURRENT: '73 T/A clone, boring at the moment...
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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Steve C.
Crazy Horse

1675 Posts

Posted - 30 Jun 2017 :  3:01:31 PM  Show Profile  Reply with Quote
Look at the numbers for the Voodoo 60903 and the numbers for Crower 60243 that I previously mentioned here as a suggestion, both are within 1 degree at .050" valve lift on the intake side.

Voodoo:
Advertised duration rated at 268/276 degrees.
227/233 at .050"
0.489"/0.504" lift.
110 lobe separation

Crower:
Advertised duration rated at 284/290 degrees.
228/235 at .050"
0.479"/.494"
112 lobe separation

For interest calculate the difference in overlap between the two lobes.
The overlap period has a profound influence on the running characteristics of the engine. It effects both the low speed and high speed characteristics the engine.

http://www.wallaceracing.com/overlap-calc.php

Be sure to use the advertised duration, not the .050 numbers. On that subject I'm not sure if Lunati and Crower rate their advertised duration (.006 being typical) the same, but use the numbers here anyway as they will be close enough for the purpose here.

Many do not pay much attention to it but for interest here look at the "CAM PROFILE INTENSITY" between the two cams:

http://www.4secondsflat.com/Cam_Design.html



.

Edited by - Steve C. on 30 Jun 2017 3:04:06 PM
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