will this cam work?
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will this cam work?
Now i don;t know to MUCH about EFI TPI motors i'm olds 455 cabr guy running 10 all motor
so i'm helping thing kid out i found this cam for his 90 iroc
crane cams 119821 duration @ 50 214/222 gross lift 488/509
it the roller cam but i looked it up on line and it was still emissions legal but said non-computer does any one know about this cam at all it seem to make alot of power in a stock TPI any clue
so i'm helping thing kid out i found this cam for his 90 iroc
crane cams 119821 duration @ 50 214/222 gross lift 488/509
it the roller cam but i looked it up on line and it was still emissions legal but said non-computer does any one know about this cam at all it seem to make alot of power in a stock TPI any clue
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From: Philly, PA
Well, what are your expectations? Making power with a TPI is not a given. The pages of this board are littered with threads of cam swaps that result in a slower car.
On paper it looks like an OK cam as long as the LSA is at least 112*, or better yet 114*. I'm talking about mild street performance. Not many 10 second TPIs running around!
Whether it's officially emissions legal or not shouldn't be a consideration. Nobody digs into a motor to measure the cam lobes during an emissions test. It's just whether it will make good power with the rest of the TPI system and if the chip tuning will work with it. As long as it's tuned sharp (has a well calibrated custom burned chip to run the combination) and has a fresh cat converter, it'll pass the sniffer no problem. The cat covers up a multitude of sins.
On paper it looks like an OK cam as long as the LSA is at least 112*, or better yet 114*. I'm talking about mild street performance. Not many 10 second TPIs running around!
Whether it's officially emissions legal or not shouldn't be a consideration. Nobody digs into a motor to measure the cam lobes during an emissions test. It's just whether it will make good power with the rest of the TPI system and if the chip tuning will work with it. As long as it's tuned sharp (has a well calibrated custom burned chip to run the combination) and has a fresh cat converter, it'll pass the sniffer no problem. The cat covers up a multitude of sins.
Last edited by Damon; Jan 9, 2003 at 12:02 PM.
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OldsGuy,
The TPI system is designed to produce low-end torque. A cam profile with that kind of duration and the 112° LSA might not work that well at lower RPMs. Right about where the cam profile is going to start flowing and charging the cylinders better, the TPI will stop delivering air (about 4,400-4,800 RPM).
As for the "non-computer" part, a TPI uses electronic fuel injection, and therefore needs to have the ECM active to deliver fuel. I think what they are identifying is the fact that Most stock ECM programming will not work well with the cam grind. It could be really bad with a 305, and maybe only a little problematic with a 350.
There are cam grinds with similar lifts that are designed with more ramp and a little less lift and duration (.440/.454-216°) that compliment the TPI system better. I believe Crane calls them "Comp-U-Cams". Competittion Cams has the "Computer Controlled" line specifically to work with TPI engines. Comp has some aggressive ramps and wider LSA that keep overlap to a minimum, and offer specs to .500/.510-114° LSA and .510/.540-112° LSA for use with TPI engines.
As you probably already guessed, any of these is going to require better valve springs and retainers, and since there is no rocker shaft in the Chevys,will require screwed rocker studs and probably stronger rocker arms to make the most reliable setup.
455 Olds, huh? I hope you have a stout rear axle. I had one in '71 and I think I could have pulled a small freight train with it. Even in stock trim, it was a torque monster. The trailer towing axle ratio made it even more impressive.
The TPI system is designed to produce low-end torque. A cam profile with that kind of duration and the 112° LSA might not work that well at lower RPMs. Right about where the cam profile is going to start flowing and charging the cylinders better, the TPI will stop delivering air (about 4,400-4,800 RPM).
As for the "non-computer" part, a TPI uses electronic fuel injection, and therefore needs to have the ECM active to deliver fuel. I think what they are identifying is the fact that Most stock ECM programming will not work well with the cam grind. It could be really bad with a 305, and maybe only a little problematic with a 350.
There are cam grinds with similar lifts that are designed with more ramp and a little less lift and duration (.440/.454-216°) that compliment the TPI system better. I believe Crane calls them "Comp-U-Cams". Competittion Cams has the "Computer Controlled" line specifically to work with TPI engines. Comp has some aggressive ramps and wider LSA that keep overlap to a minimum, and offer specs to .500/.510-114° LSA and .510/.540-112° LSA for use with TPI engines.
As you probably already guessed, any of these is going to require better valve springs and retainers, and since there is no rocker shaft in the Chevys,will require screwed rocker studs and probably stronger rocker arms to make the most reliable setup.
455 Olds, huh? I hope you have a stout rear axle. I had one in '71 and I think I could have pulled a small freight train with it. Even in stock trim, it was a torque monster. The trailer towing axle ratio made it even more impressive.
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yes its 112* but whats the deal on the not working with the computer and he has the free flowing cats
but will he have any problems running this cam in a stock motor wiht adjust able presure Reg... and ture dual he also wants to up grade the teh injecters please let me know
but will he have any problems running this cam in a stock motor wiht adjust able presure Reg... and ture dual he also wants to up grade the teh injecters please let me know
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don't worry its a mnice set up i'm hitting high 10's in a 3900 pound car with an all motor car and a 390 gear and th350 built for it
so then could some one help me with a cam for this kid its 350 with about 80k on her so i mean what cam shoudl i look at that he coudl put int hte stock motor and get soem ***** out with doing any thing to the heads
any help would be great
so then could some one help me with a cam for this kid its 350 with about 80k on her so i mean what cam shoudl i look at that he coudl put int hte stock motor and get soem ***** out with doing any thing to the heads
any help would be great
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You could start near the bottom of this page: http://www.compcams.com/catalog/082_083.html
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From: Loveland, OH, US
Car: 4
Engine: 6
Transmission: 5
If this is a stock TPI with stock heads and stock runners & intake base, go with the "302" grind 264HR-12 on that page. Replace teh valve springs as that cam will surely make a bunch of worn-out weak stock garbage ones float.
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yea it sounds like there is a bad lifter it was making a slaping soudn perrty hard and it got bad over a day started at high rpm and then went down to idea but u can only hear the cars running and car lost 2qts of oil that sounds like it coudl be another problem
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