SPRAYED 01

iTrader: (22)

Ive been calling around to get a new cam spec for my car and have been getting a lot of different ideas from all the big cam sponsors. Im confused.

I won't list names unless its off the shelf.
These are cams Im considering for my 9.5:1 forged 370 with a t4 comp 88mm turbo.

Tu2 by speed inc 236/236 578/.578 112.5lsa.
This cam seems to go against everyone elses and everything ive read about good turbo cams. But has great reviews and from a great shop, just dont get the 112.5 lsa and low lift.

I was spec'd a 225/231 .610/.612 on 115lsa.

Then one said since its a t4 on a 370 a 232/227 .600/.600 115.

My current cam was spec'd from a big shop, its a 232/236 .595/.602 115+4lsa on xer lobes.

My issue is the xer lobes which I hear are tough on springs and unstable. Im trying to make power past 6k and that's not happening with the current cam. Could be some thing else but for the low cost of a cam id like to have the correct one in there.

SPRAYED 01

iTrader: (22)

3600 vig 3disc,325 gears, ported 241 heads, ls6 intake/tb. 3840lbs Trans am with a tbrake, street driven but going for low 9s.

Best time so far is 9.8@138 at 20psi.

98Camarod

iTrader: (43)

Can you give more info on the turbo setup? What's your converter slip %? How much boost are you leaving on? what's your 60'?

ablakez28

iTrader: (9)

I made 975rwhp with my last setup with a TU2 cam
418+S88 18psi

My current build is going to be using their TU1.5 cam
6.0+S480 looking for 700ish for now.

yenkomike

iTrader: (2)

if it wont pull over 6k I don't think the cam is the issue .sounds like a backpressure or valve spring problem. if it has high backpressure it will pickup power with less cam. some guys are getting up to 65-6600 rpm with an isky triple 12 cam and it is much less duration than all of those cams listed. what is the turbine wheel size and housing a/r. ?

hellbents10

iTrader: (10)

Cam number two is the closest for a t4 but needs a little less on the exhaust side. It is easy to over cam the T4 housings. The speed inc one would be great with a free flowing housing though.

Forcefed86

iTrader: (4)

Have you measured the exhaust back pressure on your current setup? What AR t4? Exh wheel size?

willizm

iTrader: (10)

I made 735whp and 920wtq on a mustang dyno with a tu1 cam. Ran out of injector though so only pushed 15psi

SPRAYED 01

iTrader: (22)

Not sure on verter slip, I did measure back pressure it was 35psi at 20psi boost.

Its a 1.10 ar 88mm billet comp wheel with a 94/88 turbine 4 inch open dp.

Leaving on 3psi with the tbrake gets me a mid 1.4 60ft. I haven't tried more off the line but I think it could go 5psi with no wheel spin.

Slowhawk

iTrader: (12)

There are a ton of cams out there and a lot will work close to what you need.

sbcgenII

iTrader: (1)

Jim Moran @ speed inc had a 3900# Lt1 camaro fully loaded street car trapping 145+ over 10 years ago. He might know a thing or 2 about what works.

Your current cam is a 115+4 and the speed inc is on a 112.5. I bet the 2 intake centerlines are really close. The IVO and IVC are probably pretty close too.

Forcefed86

iTrader: (4)

I think that housing is more of an issue than the cam. You have plenty of wheel but it sounds more like it's choking in that 1.10 housing to me. I'd try a larger AR housing before changing out the current cam.

smokeshow

iTrader: (17)

The triple 12 seems to pull pretty well up top.

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yenkomike

iTrader: (2)

if that dyno graph is with a triple 12 cam there is no reason to run a bigger cam in most of these street engines unless they want to loose down low and add spool time.

I see a lot of cars running these 230+duration cams. to me those are max effort open dump tube , big turbine wheel cams. they work good but ad a smaller turbine and a tight convertor and it wont work to well.they spool slow and don't recover after a shift as well. better to under cam than over cam . jmho.

98Camarod

iTrader: (43)

What size tire do you have and what rpm do you cross through the traps?

SPRAYED 01

iTrader: (22)

28inch tire, about 6200 through the traps.

98Camarod

iTrader: (43)

13% converter slip. I'd give PTC a call.

smokeshow

iTrader: (17)

People just like that lumpy cam sound I guess. On the dyno I didn't go wide open with it until 3k to keep it from downshifting, and full boost by 4700 or so. Those little cams have a lot of low end. Helps the turbo get moving when it really needs it.

yenkomike

iTrader: (2)

that looks like about all the cam a stock lower end engine whould ever need if it is street driven. nice power curve.

hellbents10

iTrader: (10)

Remember its not just the power curve but the limitations of the fuel you are using has to be taken into account. Some times a "bigger" cam or one with less DCR is needed to keep the engine from detonating to death.