Head Gasket Stacking, Shims or Stock......?

[FAMILYMAN]

Okay guys...

Would you run a shim, one stock head gasket at lower boost or two head gaskets.

What does everyone run and what is everyones opinion on this subject?

 

[Ted Jannetty]

Okay guys...

Would you run a shim, one stock head gasket at lower boost or two head gaskets.

What does everyone run and what is everyones opinion on this subject?

First you must decide what kind of fuel you want to run.
Then How much boost you want to run then use the boost calculator to see what compression you have to end up with to make those two happen.

Then you can decide the best way to get to the compression you need to be at.

Now keep in mind that off boost power will suffer quite a bit as you lower compression.

In a lot of cases your better off with lower boost and higher compression if the fuel will support it.

 

[FAMILYMAN]

I want to be able to run 93 octane all day long. Drain the fuel and put race fuel and turn up the boost.

Something failed in my motor. Im tearing it down this week.

 

[Ted Jannetty]

I want to be able to run 93 octane all day long. Drain the fuel and put race fuel and turn up the boost.

Something failed in my motor. Im tearing it down this week.

93 octane stock motor 7 psi all day long.
108 octane stock motor 14 psi, but serious clutch changes.

 

[Travis Moore]

I want to be able to run 93 octane all day long. Drain the fuel and put race fuel and turn up the boost.

Something failed in my motor. Im tearing it down this week.

Brett, is there anyway that you can start out your riding day on a full tank of race fuel and lower the boost as you add pump gas throughout the day?

I start the day on a full tank of AVgas@12psi, turn it down to 10 when I fill back up with 93 (around half a tank if possible), then down to 7 psi when I fill up again. About 1000 miles like this with no problems.

T

 

[FAMILYMAN]

I figured 10psi with double head gasket at 93 would be safe. I just removed the head and I had two head bolts on the exhaust side that loosened on me.

I am going to set the studs at 5ftlbs and try again.

 

[Turk]

At 10 pounds boost 10:1 ceramic coated pistons & extra head gasket 91 octane all day long for 1/4 mile bursts. 12 pounds on 91 but no more then 1000'.

 

[Need for Speed 2]

loose head bolts do you think detonation contributed to the bolts getting loose.

 

[FAMILYMAN]

I was told to hand tighten them into place. This time they are torqued down. Not much, but they arent going anywhere.

Everything felt really good.

 

[snowy1]

I was told to hand tighten them into place. This time they are torqued down. Not much, but they arent going anywhere.

Everything felt really good.

are you sure your not pulling the studs out of the threads I have had that problem, I had to heli-coil all of them, hoping that takes care of it.