Hey everyone, I am a new guy on this board and I have a little question about checking pushrod lengths. I am in the middle of rebuilding my first small block and am not sure how to correctly check the length of the pushrods. I had a valve job done on the heads but truthfully, those heads were machined long enough enough ago that I don't remember if they surfaced them or not. I have a Manley pushrod length checker tool but am not sure if I am using it correctly. I guess my question is, could some one tell me how to do this properly? Any tips would be greatly appreciated! Thanks!

-Keith

 

if your heads were just surfaced and not plained and your block was surfaced and wasnt decked then i would use stock length pushrods. i used stock length pushrods in my motor after the heads were surfaced and i dont have any problems. the only thing i got asked by the guy that was doing my heads was if i was using stock length push rods and what the lift on my cam would be because he revalved the heads and was putting in new springs and wanted to make sure he had the righ seat pressure so the pushrods didnt bend. usually the shorter or longer pushrods are just used to get the rocker arms centered on the valve.

 

Stock length but hardened would be fine.

 

okay, thanks.

so i guess stock length it is.

.....now to call summit.

 

Get an adjustable pushrod from Comp and just check the length. More than likely youll be using a stock pushrod, but if you have any modifications done to the engine/valvetrain (especially since you dont know exactly what was done to the heads), its cheap insurance that costs no more than a length checker and a few minutes of your time... Do it right now or maybe do it again with worn out valve guides and broken valvetrain parts.

 

I've actually got one of those too (Actually, its a TrickFlow - was not the one I wanted from Summit, but just kept it anyways). To use that, I am assuming I would tighten down the rocker on the stud to get an accurate measurement, correct? .... Or how would I do that?

Thanks!

 

It depends on the type of checker. Some of them are like a micrometer, they will tell you right on the rod what length you are at, but others have to be measured with a dial calipers after the correct length is found. You will need a solid lifter, hyd. lifters wont work. Im using a hyd. roller cam which has taller lifters, so what I did was used a solid roller lifter, measured the pushrod length, then added the difference between the solid and hyd. lifter height. To check the length, I use a black marker on the tip of the valve, then while the ink is still wet I set up the rocker to zero lash, then turn over the engine and observe the pattern the rocker leaves on the valve tip. You want a pattern very near the center.