I'm redoing my valvetrain, and I'm measuring out my pushrods. Following Vettenut's instructions I have determined that my car likes between 11 and 11.25 turns to get the rocker snug, so if I go off 11.125 turns I am right at 7.35625. How much preload should I add in? I'm going to try and run out and grab these pushrods in the morning. Thanks!

 

.080 for stock lifters would put you at 7.43625 so the stock 7.4s will be a bit loose, 7.425s would be better, 7.450s would be nice and and quiet although some would say it is too much preload.

 

What type lifters are you running?

 

LS7 lifters. Sorry I didn't specify. Yella Terra rockers too.

 

If your calculation is correct then 7.425s
Are you sure you measured on base lobe of cam with piston at TDC?

 

Yes, on cylinder #2, the piston was at the top of the cylinder and both valves were closed. Will the 7.425's quiet it down some? A few of my lifters have collapsed or bled out when the engine was sitting and it only ran for a few seconds, so I know some of the noise was from that.

 

7.425's quieted it down quite a bit! Much quieter than it was with those trashed HS modded stockers!

 

Enjoy....

 

I will, thanks guys! I almost think I could get a 7.45 in there, but I don't feel like spending another $100 on it.

 

Did you have some lifter issues that contributed to the valvetrain noise? Now that I've got a quieter exhaust on the car, I realize the valvetrain noise more.

I've been thinking of Morel lifters, and Yella Terras, whenever I have the motor freshened up in the future.

 

I think they just weren't pumped up all the way, and the slop in the valvetrain from the short pushrods made it worse. Sounds good now! Still kinda noisy but its to be expected!