Yella terra Rocker installation ?'s

[kealap]

I put some 1.7 yella terras on my '99 SS a few months ago and used the LS1HOWTO.com instructions. My question is this: The kit comes with enough shims to only use 1 per valve. Doing how the LS!HOWTO.com shows to I had to use 2 shims per valve. I have aftermarket MTI heads and cam and was wondering if this is normal to use more than the supplied shims. I also have hardened pushrods. Every once in a while I will hear a tick at start-up, but it goes away. Car runs good, just want to make sure that I don't have them shimmed too much, in which case my cam's lift would be lessened and lose power and so on. Yella Terra's site is down right now. The rockers didn;t come with instructions anyway.

[shady milkman]

I put some 1.7 yella terras on my '99 SS a few months ago and used the LS1HOWTO.com instructions. My question is this: The kit comes with enough shims to only use 1 per valve. Doing how the LS!HOWTO.com shows to I had to use 2 shims per valve. I have aftermarket MTI heads and cam and was wondering if this is normal to use more than the supplied shims. I also have hardened pushrods. Every once in a while I will hear a tick at start-up, but it goes away. Car runs good, just want to make sure that I don't have them shimmed too much, in which case my cam's lift would be lessened and lose power and so on. Yella Terra's site is down right now. The rockers didn;t come with instructions anyway.

tick at start up is good ol' piston i think almost every ls1 does that..but now you say you have Aftermarket heads ...are they floating pin heads? but anyways yea dont worry about the ticking just the ls1 doing its thing..think of the ls1 as a bad morning person when it first wakes up its cranky and bitches alot (the ) then once it gets all the way up and drinks its cofee its golden and ready to role

[Killer_bluebird]

So you needed more shims to get the right preload? If so you should be fine. I have a set and I needed to use 1 shim with my stock heads and Patriot Springs. I took them out after my cam swap because it appears that I need longer pushrods to use them with my cam. When I installed them some of the rockers would still be able to rock off the valve (so that there is a gap between the rocker tip and the valve). I know it was not a collapsed lifter because when putting the stock rockers back everything was tight. I'll probably get some pushrod checkers and look this over during the winter so I can put them back on.

[9t8z28]

I think you should have researched the question about the shims. My guess is that it only needs one shim per valve or they would have gave you more.

[Killer_bluebird]

Did you do the wipe test? to make sure that the tip is centered on the top of the valve? When I tried without the shim it was slightly off torward the top (upper part of the valve) after I put one shim it was perfect and the Preload was not. For some reason it seems that I need longer pushrods with these rockers. I'm using 7.4' with the stock rockers with with no problems. But since the car will be in the higher rpms (3,000-6,800) for extended period of times I wanted the stability of shaft mounted rocker and not have the possibility of needle bearing failure of the stockers.

(edited above for clarity, I was not correct in my terminology)

[vettenuts]

Shims adjust the wipe pattern. Did you check the wipe? Pushrods set the preload, unless they are fully adjustable.