wilwhite2kss

iTrader: (2)

This will be long. I bought a top end kit for my ss, it is tfs 215's, 1,7 harland sharp (non adjustable) rockers, with gm head gasket , 7.5 push rods, ls7 lifters etc. I wanted to bump up compression, so i milled the heads from 64 to 61cc's When they milled my heads they told me that the heads were only 63cc's nd that only .012" needed to be taken off.I also bought a .040 cometic head gasket. This is what i cant figure out. Now that i milled the heads and changed the head gasket, the push rods will not work without shims. I new this would be the case, however i am having trouble finding out what the lengths should be. I have a push rod length tester, but i am scared to make a mistake. This is my first time doing rockers. Can i subtract the material taken from the heads and the difference from the thickness of the gm compressed gasket and the cometic compressed gasket, subtract it from the 7.5 push rod to get the new length push rod, or does it not work that way. I know i will need shims, but what size? I need help step by step, and a fool proof method of checking if it is correct before i put the rest of the motor together. Does the piston have to be at tdc when checking for length? How will i know its at tdc? Does it also have to be on a certain stroke? How will i know that its on that stroke? Do i have to do certain cylinders or valves first in some kind of order? what is the order? When is the adjustable push rod adjusted far enough and not compressing the lifter, or should it be compressed a bit? Is there a certain clearance or tolerance that i have to have between the roller and the valve spring? As you can see , i am lost. I feel like an idiot because i have read so many instructions on this in the search engines, and i still cant seem to figure it out. Someone who has done this many times , and can explain it to an idiot please take the time and chime in. It would be much appreciated. Thanks in advance.

DaddySS

If you do a search on pushrod length checker we posted the step by step instructions. All you need to know is the reommended preload for your lifters, then use the length checker. When you're done a quick sanity check is when you tighten the rocker bolts, each 1/2 turn past 0 lash = .025 preload. It's not that complicated but I can tell you that 7.5s are probaly too long.

wilwhite2kss

iTrader: (2)

Yes , i agree that the 7.5's are too long , but as far as the preload, how can i set a preload on a non adjustable rocker. You torque it down to 22ft lbs an call it a day if you have the correct size pushrod. the reload would already be equated into the length of the pushrod , correct? Thats why with non adjustables you have to have the correct length or shims. Your only options are to change the pushrod, or get the correct size shims for the rocker pedestal.

DaddySS

In the step by step, you measure 0 lash, then add your preload. So let's say you measure 7.27 on the checker and you want .080 preload. 7.27 + .080 = 7.350. So you get 7.350 pushrods, torque them to spec and you have .080 preload.

Daniel92

What? If you have so many questions putting in a motor, you shouldn't be doing it.

Jason 98 TA

iTrader: (4)

We stock pushrod length checkers & just about every length pushrod you could need, give us a call & we can explain checking it.

vettenuts

iTrader: (4)

Hope this helps: Link

wilwhite2kss

iTrader: (2)

I knew there would be some *** that would make a comment like that. Is that the advice you told or will tell your kids when they want to learn how to ride a bike? "You dont know how to ride a bike , so you shouldnt do it" I am fine with everything else , i just dont know how to adjust rockers. I have asked several people and keep getting conflicting information. Also, im not putting in a motor. Im sorry if im not like you and pay other people to install everything for me. This is how you learn. YOU ASK QUESTIONS! This is also one of the reasons the site was created. Everybody else , thank you for all your help, its nice to know some people arent ******** and can lend a helping hand. It is appreciated.

socmguy

iTrader: (18)

^^I agree, Daniel92 is a douche. Good luck getting it all worked out and post a vid when it all comes together!

wilwhite2kss

iTrader: (2)

Vettenuts, daddyss, and jason thanks for the advice again. I read everything and this helps a ton. I wll be working on it this weekend and should ddo fine following your write ups. The only question i have is , where do i find my preload spec? How do i know what it should be set to? thanks


When its done , i will be posting a vid and numbers after the tune Socmguy. Thanks for the support with u know who.

socmguy

iTrader: (18)

Anytime man. search his other posts. He can't figure out how to use seafoam. Just call TSP for the preload info. They're a great help.

JakeFusion

iTrader: (7)

You'll probably need to run shims anyway on the TFS heads under the rockers, just to get the geometry correct. Take a black marker, mark on the roller, and "tap" the rocker on the valve. See where the line is - if its too far to one side or the other, you'll need to shim it. Pushrods won't change the geometry much unless they are really off. Most of the time a .47" or .50" shim is required to get the geometry right with those rockers and that head (though the Harlands seem to be less fickle about shims than the Yella Terras).

Also, I think the 7.5s are going to be about right. With the LS7 lifters, you can run a lot of preload without worry and that will give you power (due to better valve control high in the RPM range). Preload recommend range is .60-.100" for the GM lifters, but .120-.140" seems to work even better. I bet a 7.450" is going to put you in the .60-.100" range with the checker, but another .50" will get you into that .120-140" range.

Daniel92

lol, your right, this post actually helped me feel better that this guy is trying to put together some part, and I was worried about putting in seafoam.

wilwhite2kss

iTrader: (2)

So a .120 -.140 range is not to much? Would it be safer to be around the 100 range? Also , Is this the range you run on your setup. I would hate to hurt my new setup. How far is the is the max for the lifter? I have read that it is .160. Is that cutting it close?

porsche914ls6

iTrader: (1)

I'll second that! Hey Daniel...If you don't have anything constructive or helpful to say, keep your ******* mouth shut. One of the largest reasons this forum exists is for members to post questions and get advice from others that have practical experience in one regard or another. Looks like the only thing your good at is being an *******. Perhaps there is an "******* forum" somewhere where you can be useful.

Daniel92

how rude, who are you?