Help with preload and Yella Terra Rockers
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Help with preload and Yella Terra Rockers I got the Yella Terra rockers for the LS1. I have 7.4 TR pushrods, TR224 Cam, TEA 5.3L Heads that are suppose to be milled to about 11.1 compression.
When I bolt up the rocker on #1 at TDC and check the preload I get about 2+ turns. Their instructions say to add shims to decrease the turns. Yet, it takes 3 shims to even get close.
So, would you say my pushrods are too short?
When I bolt up the rocker on #1 at TDC and check the preload I get about 2+ turns. Their instructions say to add shims to decrease the turns. Yet, it takes 3 shims to even get close.
So, would you say my pushrods are too short?
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Re: Help with preload and Yella Terra Rockers Doh! It needs a pedestal and shim and now I am closer to a good preload. I still may need to get different length pushrods.
My preload is about 1 1/4 turns before 22 ft lbs. What change in pushrod length would I need to change the preload to < 1 1/4 turns? Longer or shorter than my 7.4"?
My preload is about 1 1/4 turns before 22 ft lbs. What change in pushrod length would I need to change the preload to < 1 1/4 turns? Longer or shorter than my 7.4"?
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From: Berkeley, California
Re: Help with preload and Yella Terra Rockers To compensate for milling the head you need a shorter pushrod. To compensate for the smaller base circle of a high-lift cam you need a longer pushrod. Shorter pushrods are preferable to shims under the rocker stands. Your description leads me to think you need shorter pushrods. I think you should try 7.35 pushrods and eliminate the shims. And you should also get another opinion; just to be sure I’m not way confused. If Ron, Kimchee and Rice, replies, you can trust his recommendation. He really knows this stuff.
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Re: Help with preload and Yella Terra Rockers I've done several sets and in both instances used 7.350 p-rods - 3/4 -1 turn preload.
I beleive your 1 1/4 turns is still reasonable but wouldn't recommend more than that.
I beleive your 1 1/4 turns is still reasonable but wouldn't recommend more than that.
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Re: Help with preload and Yella Terra Rockers I just ordered 7.35 from Thunder Racing and a pushrod length checker in case 7.35 is not short enough. The shims are already on the car but I would say they are at least .05. So, if the 7.35 drops me 1/2 to 1 turn then I wonder if I take the shims out where will it put me. I expect .05 to a .1 change to get be below 3/4 turn.
