Originally Posted by Blusmbl
Originally Posted by fast68plymouth
Before deciding on whether or not spring shimming is necessary....... go to the spring page on the TF site and look up the specs(TFS-16094).

You’ll see they don’t agree with the paperwork that comes with the heads........ but they do agree with the specs that the spring manufacturer shows for that spring(PAC 1294).

On my tester, the springs match the PAC specs.


, which sounds like more than enough spring rate and I definitely shouldn't shim them, if anything it might be too much spring.

Yes, and I've known many to use the 928 spring but am not remembering the loads. Guess what I'm getting at is you need the spring matched to the cam regardless if it came on the heads or not. That said, sounds like Dwayne is directing you properly.