231/237 cam longtubes ls6 intake speed inc tuned 360rwhp????

[99Cammed]

Hello everyone im new to posting on here but I read it every day. I have a 99 trans am ws6 with si5 cam from speed inc, longtubes, ls6 intake, and lid. I had it dyno tuned by speed inc and ended up with 360rwhp at peak. It runs and idles like a dream. Does anyone think this number is low?? I must have picked up around 60rwhp from everything. Maybe some power left on the table or maybe it just has more low end rpm hp? I have the dyno graph if anyone wants to see it...im thinking my next mod this summer will be heads but thought about just spraying it...any opinions?

[SMWS6TA]

That's about right with those mods.

Your biggest hold back is the heads. If you get a set of used 243's (about $450-500) you'll pick up a few more but not enough to really justify all the work. A set of aftermarket heads will get you more bang for the buck.

If you're an auto I would get a good stall converter 1st, you'll really feel like your car is a different animal.

[99Cammed]

Its a 6 speed and I thought about that how much do you think I can gain from prc 2.5s....or should I just usr a 150 shot? Im not trying to spend a million dollars to make my car fast but I have people to race this summer and I want it done soon...I upgraded to ls6 intake over ls1 how big of a deal is it to have a fast intake with heads cam setup..also if i add fast intake do i need fuel rails etc too?

[SMWS6TA]

PRC - there are better heads out there for relatively the same price range. TrickFlow has some great heads. For the best results you need to have guys like Martin Smallwood, Brian Tooley, or Geoff from EPS spec out a heads & cam combo to get the best bang for your buck. There is a Trickflow combo pack on Summit that comes with heads, cam, pushrods, timing chain & springs that has some pretty good gains on HP & TQ.

Nitrous - stock internals can handle up to 125 shot easy with no serious risk of damage. Around the 150 shot you'll start to need tuning to safely continually use back to back. Above that you'll need to drop some $$$$ on parts & tuning otherwise you're asking to blow up the block.

LS6 intake - I will always say it's worth the upgrade over a LS1 intake. Used $300, maybe lower now.

FAST intakes - The 90 is slightly better than the LS6 intake. Maybe 10-20 hp gain difference, IMHO not really worth the $800+ when you can spend that for other stuff. The 102 intake - this intake is design for serious mod'd builds. Best with stroker builds and aftermarket heads & tuning. You'll still get gains on a cam' LS1 but unless you have some great flowing heads you're just spending a lot of money and not getting any benefits.


If you're looking for a bump in HP but not going to far out in modding the engine then Nitrous is the way to go as long as you heed what I said about how much.


WARNING - Once you start adding parts for go fast you'll begin to find your weakness in the rest of your drive train. The 10 bolt can only handle so much, (not too much over stock) before it will grenade. Being a M6 car if you run slicks or DR's you increase the chances of it going out.

If you do decide to a cam upgrade - smart money is to also get a good new oil pump (LS6 or Melling 10295 & timing chain (LS2). Reason being that you are already doing the work to do the cam swap, do it all once instead of twice and also the stock 97-99 LS1 oil pumps are prone to fail the older they get when at high revs.

Try to do cam and heads at the same time - only need to pay for tuning once, most tuning is $500 a session.

[ICRAZY6]

I used to run the same cam 231/237 as you. I also had the following: SLP Lid, K&N, Fast 90/90, Red Top SVO injectors, Patriot Performance Stage II heads, Pacesetter 1 3/4" headers, no cats, magnaflow exhaust. Running through a Yank SS3600 Stall and MWC 9" with 3.70 gears. I put down 435 rwhp and 405 tq tune by Speed Inc.

You sound like your on the right track for what you currently have.

[ICRAZY6]

I did run nitrous for a while. When Speed went to tune for it I was running out of fuel to do the 150 shot so I did a 75 wet shot. So if your going to go with nitrous you'll likely need to update your fuel system as well.

[SMWS6TA]

And also wet is better then dry shot.