Shorter rod to drop CR??

maybe I worded the question wrong. I am not looking for "maximum gasket thickness"

What I am doing is trying to determine is will I be allright running a high CR or thick gasket? OR do I need to machine or buy new pistons? The ones I have installed are flat tops with -.9 cc valve reliefs.

I have my CR at 11.1 with the .125 gaskets. I plan to CC the heads this weekend and find out an EXACT CR though.

I am leaning towards mchining the pistons.

 

Thinner wasn't tried.
Upgrading to better surface finishes and fixing the super lean bottom end/rich top end fuel system took care of most of the problems then we added the inside bolts when we started to push it harder.

We run Clark copper head gaskets and o-ring the blocks.

If your having problems, I recommend;
1-make sure everything is flat
2-make sure the surface finish is smooth enough (for copper)
3-retorque after a new gasket is put through a few heat cycles
If your still pushing them out, then;
4-make sure the problem isn't your fuel system
5-add the inside head bolts as your probably pushing the gaskets out at cyl#2and/or 7 (BBC)

When faced with thinner or thicker copper gaskets I choose the thicker, they conform to irregularities better.

 

new motor, no problems yet and hope this is to prevent those.
but all this is good info thanks!

 

One thing I was told by Carrol Carter is to be careful using a shorter rod because you can have clearance problems with the piston skirts and crank counterweights. Mine was spec'd at 11.3-1 compression with a .070 copper head gasket. Not running yet but was told that it will be no problem and I also have 10 bolt TFS heads. Just something to consider before you buy a set of shorter rods. Chris

 

Comp

Save your self a head -ake or two Call the Manufs. But don,t limit your self to just one. Alot of people answer the phone.If you get the same answer all around go for it. Just keep an eye on it. Pull the heads after a couple times out, and check. May learn more than just if the gasket looks good. Do the O- ring thing. Good luck. Just a thought. Don

 

I think the other guy was buying shorter rods. I have no intentions of buying shorter rods. I might buy a thinner head gasket though. Like an .085 I think the will get me 11.5.1 but will double check.

 

Some use shorter rods in problem cylinders. T/F have been doing this for 30 years.