Trick Flow GenX 255 LS3 Heads Rockers Stripped out!

[John_C]

Originally Posted by Greenhornet2

So with your 1.72 rockers you were at .657" intake lift that is damn close you might have better luck now that you are changing back to 1.7s i have a feeling you were getting coil bind maybe on the tight side for preload i would double check what length you need to be sure maybe need a touch shorter on the pushrod length. Just speculation of course.

Theoretically, yes.

From what I can see, it had no signs of coil bind.

If I did have coil bind, I doubt it would have lasted as long as it did.

I put this n/a setup together in late 2017.

Then Jan 2019, I added a Stage 2 ProCharger D1X and bigger fuel system.

I wasn't easy on it.....

[Greenhornet2]

Originally Posted by John_C

On a LS3, TFS recommends a 7.750-7.800 pushrod with GenX 255's as far as I recall.

Depends on the cam base circle. The length has to be checked with the cam you are going to use with the push rod length checker tool.

[John_C]

Originally Posted by Greenhornet2

Depends on the cam base circle. The length has to be checked with the cam you are going to use with the push rod length checker tool.

I bought a Comp Cams pushrod length checker and my installer had it to use.

It shouldn't have been a problem to get correct measurements on the original setup.

[christianchevell]

Bummer I used to build old school SBC a lot , I never went with twisted wedge / trick flow etc..etc ; I just used Mast/Edelbrock and stock mostly because...well that had a rep...the opposite of edelbrock…. so good luck there, and of course use a good sealant of those bolts when your done dumping money into the heads...… Not the first time aftermarket heads have failed, sometimes right out of the box....

[eLeSthree]

I've never seen a rocker break on the pushrod cup. Usually broken on the valve stem side. If you have a dial indicator, you could set it on the top of the retainer and see how much the valve spring is compressing, to see if it is coil bind. But like you said, you ran this NA for a while.

One thing I notice, and maybe I'm wrong, you can tell me. The rocker stand you're running looks pretty thick. Which is probably why TFS heads need longer than normal pushrods, but that would cause you to have less rocker bolt thread engagement. Are you running an aftermarket rocker bolt? I think I have some spare COMPs, let me go measure them.

[eLeSthree]

I’ve had these forever, not even sure where they came from. If they provide more thread engagement, theyre yours if you want them.

[John_C]

Originally Posted by eLeSthree

I’ve had these forever, not even sure where they came from. If they provide more thread engagement, they're yours if you want them.

I appreciate it...

But we tossed the stock rocker bolts for the TSP bolts which were longer and look just like the one in your picture.

We got all 16 rocker bolt holes in the heads helicoiled, so hopefully this doesn't happen again.

[John_C]

I've not driven it but maybe 10 easy miles just to fill up on e85 and the car wash.

But so far so good.

Going to put a new TEHCM in with fresh fluid and filte.

Once that's done, I'm mounting up some DR's and hitting the 1/4!

Wish me luck!

[*_ERIC_*]

Originally Posted by Greenhornet2

Depends on the cam base circle. The length has to be checked with the cam you are going to use with the push rod length checker tool.

My GenX 255's took a 7.935 pushrod. Using different springs of course with a custom cam. Of course that also factored in the preload from the Johnson 2116's.