I had 1.6" on my car stock but now i'm having the engine re-built and i have a complete set of AFR heads....the valve springs on the heads and the cam i chose with 1.5 rr's is OK...but i would have to change the valve springs if i kept my 1.6 rr's not to mention i will now have to tear down my complete head package...due to necessary machine work....Doe going back to 1.5 rr take that much power away if any...I'm not sacrificing too much am i......

 

Need more info??? Like what size lift cam? Almost all manufac's make springs that will go up to .600 lift that require no machne work to heads......with that in mind (and if your really good) all you need to take off is your valve covers to change rockers and springs. I did mine with my cam install so I had the intake off as well...changed springs without removing a head bolt. Go to Shoebox's website for details. Oh and yes...I think 1.6 rr's are worth it....especialy for someone like you that has some good flowing heads...

 

I imagined that it would be worth it.....but by how much.....I know that some springs would not require machining of the heads but still in all...this is being done at a shop....the labor involved with tearing down the heads and setting up new valve springs, I didn't think, would be worth the amount of gain produced by the 1.6 rr's.....and by the way, i'm putting CC 305 LT1 cam in this car...and with 1.5 rr's....gets about .510 lift and with 1.6 rr's gets about .540.......and the valve springs already installed just about max out at .550..........

 

Depends on the lift of the cam really. I personally like to achieve lift with the cam and keep the shorter rocker arms. I've heard shorter rocker arms can be a little more stable in nature at high rpms than the longer ones.

Jason