svtrich

thinking about a cam change but need to stay small because of california smog.plus my buddy{his car} wants something that still idles smooth.that why I wondering about the 204 218 .551 .551 ls6 cam
car is auto. Rich

Sparo2

I think you'll get better results with a bigger cam. I've seen guys with bigger cams than that pass CA smog. The key is tuning, smog equipment and of course a cam not too big. Cams that pass usually end up with a 116LSA or bigger.

If you're stuck on the LS6 cam I think you won't gain much more. You'll have better luck putting that money towards bolt-ons like EWP, U/D pulley, FAST intake, ported TB or even ported heads...which is easier than a cam swap.

I would contact Charlie @ RPM Motors. He can set you up with a good cam that'll still pass smog.

Just my opinion.

Jim_H

I agree Charlie picked a great cam for me that passes. The new testing laws going into affect are only ODB testing looking for error codes.

There are also a minor issue with the LS6 cam, it has a smaller base circle diameter so you'll need to do something like different pushrods. I think Charlie can pick you a better cam that meets all your requirements with more power.

LS1LT1

It's just not a big enough jump to justify ALL of that work to install it. I'd maybe go with something slightly more aggressive but still totally streetable, perhaps in the 218/222 .560/.560 range?

xstang

If you want to sound stock get a Cheater cam from TR.. Or just spend the money on AFR 205 heads (or Trickflow) (you would sound totally stock). I used that combo through the stock catback and put down 450rwhp on my ls2..
You couldn't even tell it was in there!

JoesC5

This info might help you.

http://www.gmhightechperformance.com...sts/index.html

http://www.hotrod.com/techarticles/1.../cam_swap.html

CF member RLSebring had a LS3 with the GM Hot Cam crate engine, 480 bhp and he had trouble with it. He replaced the Hot Cam with a stock LS7 cam and said the car runs perfect. The LS7 cam is 211/230 at 121 LSA but using the LS3 1.7 rockers the lift would be .558/.558 instead of the .591/.591 when used in the LS7 with 1.8 rocker arms.

gunterwalker

I think its a waste of time and $$$ to install that cam. What you are going to see in performance won't even come close to what you will spend. You can get a much bigger cam and still pass smog in CA. I would look at going for that.

1FSTVET

You may want to think about just changing the rockers to a 1.8 or 1.85 with your stock cam, with the 1.8 your cam numbers will go from 225 lift to 556 lift and slightly higher with the 1.85 so either way you get more lift than the stock ls6 cam. I did the 1.8 yella terras with my stock cam and after a cleanup tune I gained 13ft torque and 18 hp and the gains were all in the most used rpm power range or under the curve.

scv8

I would love to know why GM didn't put the '02 LS6 cam in the LS2.

LS1LT1

I've wondered that as well. I mean some of us have extracted LOTS of great performance out of the stock LS2 longblock but that slightly more aggressive 2002-2004 C5 Z06 cam could've made it just that much better. Probably an emissions or perhaps a 'valvetrain noise' issue (we all know about GM's desire to meet the tightest of regulations)? Or maybe they knew the LS3 was coming eventually and just wanted to maintain that 30hp power gap between the LS2 and LS3 once it was released?

And I dig your 944 LS2 conversion, the only Porsche I've ever owned was a used 944 (bought mainly as a business move to flip it) and thought briefly about keeping it for a LSx swap.

ctusser

That and modifying the LS6 manifold design to fit the 90mm TB, and the car would have been rated ~425hp from the factory. Leave it to the engineers to reinvent the wheel and take a step back.

scv8

Thanks! I think you may be on to it regarding the emissions.

Exactly!

Joe_G

I wouldn't spend money to put that cam in either. There are better choices and Charlie at RPM is one of the best.

Perhaps GM needed the lighter sodium filled valves for that hotter cam, but didn't need to spend the money to put those in by using the smaller cam, still meeting their goal of 400 HP in the c6 "think 4's and 5's" as stated by the chief engineer before the c6 came out?

JoesC5

Don't you just hate those stupid engineers. Why didn't they just go ahead and design the C6 ZR1 back in 1952(for the 1953 introduction of the Corvette), instead of reinventing the wheel every few years?

Joe_G

I will say this....when my c6 was bone stock I raced my buddy's bone stock c5Z several times....we were dead even through the 1/8 but he walked me every time in the final 660. His cam breathed better at high rpm than mine. It was consistent. Of course my car weighed a little more but he weighed a little more than me too evening that out.

Still I wouldn't bother putting the Z cam in a c6.

ctusser

Your sarcasm is noted. No I don't hate them. They had some good parts already that could have been adapted and used. The LS2 had 18more cubes than the LS6 plus a higher compression ratio and yet comes up with 5 fewer HP. Perhaps there was pressure from upper management that the LS6 couldn't be surpassed until the release of the LS7. Overall through the generations the Corvette engineers have done a great job redesigning and refining the car.