borba

I was wondering if purchasing a new set of rocker arms (1.8) for a somewhat stock motor was worth the cost. I was told that you get about 10hp if you go to a 1.8 ratio. Will the stock heads/cam allow clearence for a 1.8 ratio? :confused:

SpinMonster

I have nothing bad to say about having them on a stock motor. You will have to change your valve springs to use them or u will get valve float. If you are planning a cam change, don't use them. I just went to a new cam and the lift will get near .600 with most good cams that you will be best served with using the money elsewhere. As far as the rockers with the stock cam it is a great mod. Hardened pushrods and a means to get adjustment into the valvetrain are big pluses. You will not have to change pushrods or use shims for changes in milled heads ect...


[Modified by SpinMonster, 9:42 PM 4/26/2003]

SpinMonster

I am sorry for mentioning this here but since I have no use for them with my new cam, I would like to sell the rockers...all parts used for 1800 miles....for $500. Send me IM if interested

bparker

I would go with the (1.7) Yella Terra rocker arms - they are MUCH stronger and many are yeilding 10RWHP from them.. They also offer 1.8s too in case you want to go for even more HP. :cheers:
http://www.yellaterra.com.au/stealth.php

vetterdstr

:iagree:

vetterdstr :cheers:

FRC Rob

Not trying to hijack the thread, but aren't there issues with certain years? I've heard that there might be clearance issues with '97-'98 cars with perimeter bolt valve covers...can anyone verify or refute this? Also, since the '99 and earlier cars had .472"/.479" cams, the 1.8 ratio would only take them up to .500"/.507". Later LS1s had .500"/500" lift...would you need to swap valvesprings on an early cam car? It seems like the '99 cars might be the easiest for adding 1.8 rockers...they've got late style valve covers (no clearance issues?) and early style low lift cams (might not need to change valvesprings?). Can anyone clarify these issues?

Thanks,
Rob

SpinMonster

Valve springs and titanium retainers are cheap insurance in any valve train. There are clearance issues with some valve covers but the instructions with the cranes clearly show where to shave the covers down to fit them. I have seen spacers sold to take care of the problem too that moves the covers out a bit to clear them. I think the cam lift on the early years still gets you too close to the .530 lift limits of the stock springs that are now 5 years old and may be out of spec. The Z06 springs are ok for the early year cars and are a bit cheaper but I would still use titanium retainers. I have changed spings with the heads still on the car. It is no big deal. You just need an air compressor fitting to pressurinze the cylinder.