Turbo Cams?

[XiKeiyaZI]

o_o So basically... for a bit of extra HP... grab 1G manual Turbo Cams (Both exhaust and Intake?), slap them in.. and that's it? No ECU tuning or anything?

 

[woomer]

o_o So basically... for a bit of extra HP... grab 1G manual Turbo Cams (Both exhaust and Intake?), slap them in.. and that's it? No ECU tuning or anything?

nope works great ---------just dont get the ones from a automatic get 5 speed cams - just did the swap and was skeptical but trust me it helps and thats just on the butt dyno

 

[dsm-onster]

The manual turbo cams from 1990-1992 are exactly the same except for the timing. If you were to "upgrade" to these, then you would only be altering the cam timing on the intake cam and would only need the intake cam to make any difference. The exhaust cams for all n/t, auto and 1990-1992 manual turbo motors are the same. Monkeying with cam timing is setup specific. Your setup may not benefit from more intake retard at all, which is all the 1990-1991 cams do. In fact you're taking AWAY overlap by running the turbo intake cam; turbos for the most part benefit from less overlap and n/t motors for the most part benefit from more overlap. In all likelyhood, you'll be just making the motor more peaky (more peak power less power under the curve). This is what happened to me. I lost some volume flow (hertz were cosistantly slightly lower from 2500-4500rpms), but went up a little after 5000rpms but it all died by 6500rpms anyway with the 1g intake manifold. I felt that it was a waste of time. No butt dyno, actual view of the airflow curve.

The manual turbo cams from 1993-1994 have a higher duration exhaust cam than the n/t, auto and 1990-1992 manual turbo. They also have SLIGHTLY, SLIGHTLY higher lift with both cams. Still has less overlap (different intake timing: same degrees retarded vs. n/t intake cam) Considering all the gain from the SLIGHTLY higher lift can be lost with impoper timing to your n/t setup, you're only really gaining from the larger exhaust cam duration running these cams. You ARE shifting the power band up slightly with closing the intake valve later, but again does this work with your setup? If you're running a stock manifold the likely this is of zero benefit. But the exhaust cam being that it is larger for these 2 years can probably really help. So I'd retain the stock n/t intake cam to keep your intake timing more in line with n/t usage and grab the larger 1993-1994 exhaust cam. You won't have to redo your igition timing swapping just the exhaust either.

The 1995-1999 maual/auto cams are identical to 1993-1994 turbo manual cams (same timing and same larger exhaust duration), with the SLIGHTLY, SLIGHTLY lower lift that the 1990-1992 cams have.

Ideally: you want both 1993-1994 turbo manual cams and use an adjustable cam gear on the intake dial it back in to the n/t intake cam timing. But that cam gear costs more money than the cam upgrade. And really you should go ahead and buy two adjustable gears and get your timing spot on for your particular setup if you're going through the trouble. And really get some good gains with spot on timing AND the SLIGHTLY higher lift and small increase in exhaust duration.

Cam gear purchase and effort swapping the cams for marginal gains . . . You could nearly as affordably swap in a set of delta 272 regrinds for about $200 shipped. And have WAY more lift and WAY more duration.

 

[woomer]

I realy appreciate you taking the time to explain all of this to me ----im going to look into the delta cams --im just hoping i didnt hurt my performance any ----we run 1/4 mile dirt track and usualy carry between 4-7 grand running second gear might be a few weeks till i can place my order---but after installing the cams my compression went over the hill -----215 on 1 - 215 on 2 - 170 on 3 and 170 on 4...........the car feels snappier but after what im reading from you this old butt dyno i have may be wrong.............again thank you

 

[dsm-onster]

For your compression to change that much, then something else probably was remedied why the swap.

You really need to just log before and after hertz counts. This will tell you whether or not the turbo cams are working for your setup. They may work just perfect for your intents with the car, but then again you also fixed something sice your compression went up quite a bit.

Sounds like 272 regrinds would be great, sice you're wanting power from 4K all the way to 7K. The cams will "come on" at about 4500rpms and then you'll keep pulling through the gear all the way to redline.