Anybody that has stud mount RR's, got Q's

[vikingpower]

So I got my TFS heads and was reading the tech paperwork they supply with them and there is one that talks about setting the rocker on the valve so the roller tip is centered on it (at 1/2 peak lift), and so that rocker tip travel on the valve stem is less than or equal to .080" (to minimize valve guide wear). My question is, has anyone not been able to use the pushrod length recommended for their head manufacturer? The directions say to measure the pushrod length then order them.

 

[Carbed86GT]

The only way to do this correctly and avoid headaches is to use a pushrod length checker available thru jegs or summit for about 12 bucks. Lots of things such as decking a block or heads can make you need shorter than normal pushrods.

 

[maverick0716]

I totally agree with Carbed86GT

 

[CManT1914]

Although measuring is the best way to determine what length pushrod is needed, the kit that TFS sells (heads/cam/and intake) come with the 6.750" pushrods with it. So these should be the correct size pushrods as long as you haven't had the heads milled or whatever. That's what I ordered, I guess I can let you know if they end up not working, lol.

 

[nmcgrawj]

6.75" was what i used with my custom cam too. Cams can also change the desired length but not but a lot. It usually takes more than .050" of a difference in length for u to be able to start seeing it.

 

[JerryDaugherty]

wut is stock size? and wut can happen if you use the incorrect size?

 

[nmcgrawj]

wut is stock size? and wut can happen if you use the incorrect size?

Im not sure what the stock size is. If you use the incorrect size then the roller rocker will not push straight down on the valve. It will push it to the sides causing extra wear to the valve guide. If you use too short it wont even reach obviously.

When you turn the motor over you want the roller rocker to stay relatively in the middle of the valve stem. It normally goes goes from the lifter valley center to the header side center of the valve stem if that makes since.

 

[maverick0716]

Stock is 6.25". My Edelbrock headed combo needed 6.30".