While figuring pushrod length/rocker sweep/geometry this evening, I found that it was much easier to use a pair of studs I had sitting around for "mach"-up purposes. Since we're not able to access the pushrods on these LS engines (I'm used to SBF's), the rockers must come off to adjust pushrod length.

In doing all of this (and being relatively new to the LS stuff), I wondered if anyone actually runs studs instead of bolts. Even with a GT19 cam and yellaterra 1.8 rockers (.677/.688), the stud protruding beyond the nut doesn't interfere with the rocker body and it was much easier to mess with the shim deals and remove/install the rockers.

I had these on the shelf for a different project:


The broached end threads adequately into the heads:








Again... they worked great for mock-up purposes. I'm just wondering if this is a good or bad idea for actual use. Seems like it'd be alright to me, but wanted to post up and get some opinions... good/bad/otherwise.

Thanks.

 

I have thought the same and would like to know.

 

as long as the studs/nuts dont interfere with the rocker movement, I think its an improvement

 

No interference at all...

The only problem I'm seeing is the tensile strength of the ARP stainless 300.

A 12.9 bolt (like what comes with the YellaTerra rockers) has a ~176,945psi tensile strength where the ARP 300 has an advertised 170,000psi tensile strength. Pretty close. I'd like to get 8740 moly studs or better (180,000+).

These are absolutely awesome for mock-up/valvetrain work (figuring pushrod length, etc.) but I may wind up using the allen bolts. We'll see.

 

I would not use stainless on anything inside of the engine.

I would also be woried about pulling the threads out of the head.

They will also loosen up with heat.

Just not a good idea

Tim

 

I ended up going with the grade 12.9 socket head cap screws that the rockers come with and just used the stainless studs for mock up purposes. Some ARP 8740 chromoly studs torqued to spec would be nice but not absolutely necessary, I realize.



Gettin' close...

Thanks