How many shims are too many?

9 Deuce GT

Member
Dec 10, 2003
550
1
16
Geneva, NY
I put AFR 165 heads on my car a few years ago. When I installed the FMS roller rockers, I had to put shims under all of the rockers. Some needed 1, others needed 2. None of them took more than 2. I just installed a TFS Stage 1 cam last weekend. Now I am rapping up everything. I tried to adjust the pedestal roller rockers, and realized that I needed more shims. I oredered more and adjusted them today. It just makes me nervous to put a bunch of shims in. Not all of the rockers required more than before, but some required 2 thick shims and one small shim. That just seems like a lot. There is minimal paly in some of them, while the rest seem pretty snug like thay should. What's the deal?
 
My friend had the same problem you are describing. His setup was almost the same as yours, 306, AFR 165s, B cam, larger injectors, intake, etc. HIs car sounded like a large diesel engine CLICK, TICK, CLICK, TICK, loud. Ran killer but sounded like the lifters were destroyed. He took the shims off of his heads and the noise was almost gone. A little clatter could still be heard, but with Aluminum intakes and exhaust, not more noise that I would expect from any other stang with the same mods.

Now the motor is mine except the intake and I am changing the B cam out. I have heard good things and been referred to Ed Curtis from Flowtech for a personalized stick. Maybe try him.


I have also read several instances where people with the TFS1 cam having surging/rough idle problems, just FYI
 
That can't be good using that many shims.. From the instructions included with my heads, it sounded like going more than .090 (big and little) was about as much as you would want to go...

But if the valve geometry isn't totally out of whack and the roller on the rocker doesn't track all over the place on the top of the valve then you might be okay.

But still -- If it were me I wouldn't run it until you get shorter pushrods.