Nitrous and big block head gasket question

[court9155]

For those using nitrous on a mild big block are you having better luck with steel shim headgaskets or just standard fel pros? I have been reading on the net a bit that the steel shim headgaskets dont like much nitrous abuse versus the standard felpros.

I could give a **** about compressed thickness as the motor is already lucky to be 7.8:1

Please advise.

Dan

 

[67 coronet]

i think you are good up to about a 150 shot on any gaskets.if you are going bigger then that you may want to look at the whole motor build rather then just the gaskets.plus are you talking for street fun or full time racing.if just a street motor then any gasket will do with short bursts of go juice.

 

[wedgie]

I used to run a nitrous system on my 440 six pack with steel headgaskets, iron 906 heads, and Arias pistons. Never had a gasket problem. With your low static compression ratio, you should be able to spray quite a bit. Watch your plugs for signs of detonation, adjust timing accordingly, make sure that your fuel supply is adequate, and have fun.

 

[court9155]

Thanks guys. I am pretty well versed with the nitrous having had several nitrous cars, just none of them big block mopars and none of them cast piston motors......we shall see what happens!! tee hee hee gonna be fun!

 

[RustyRatRod]

I've run N2o in the past myself and I would never in a million years run a steel shim gasket.

 

[court9155]

I've run N2o in the past myself and I would never in a million years run a steel shim gasket.

Thanks. After looking into folks posts and talkin with my dead uncles nitrous tuner I wont be either. Composite gasket it is!! Even lower compression.....oh well

 

[Supershafts]

This all depends on the amount.

Which cast pistons, factory or aftermarket or hyper style?

 

[Hemirunner]

we ran boatloads of spray on stock cast piston steel shim headgasket 440's back in the day with great success even when we had no clue what we were doing..... now I use cometics on most of the nitrous engines I build.

 

[court9155]

we ran boatloads of spray on stock cast piston steel shim headgasket 440's back in the day with great success even when we had no clue what we were doing..... now I use cometics on most of the nitrous engines I build.

I see people getting away with amazing amounts of boost and nitrous on stock cast piston big block mopars.

I guess if the tune is right and the RPMs are low you get away with it for awhile.

Dan

 

[Supershafts]

A stock mopar cast piston will start cracking at the wrist pin within 4 to 6 passes with a 400hp hit... Those didn't have a factory stl shim gasket though.
I would never do that with a hyper piston though

I have only pushed one head gasket out of a sb as the 2nd stg hit at 250 on top of the 1st stg and that was primarily because i forgot to add the additional head torque on a regular fel-pro gasket.

 

[RustyRatRod]

I actually like the copper gaskets. With compressed thicknesses now down around .040" no reason not to use them. That's what I'm gonna run on my N/A 383. I think they compress to .043". I'm sure opinions will vary.

 

[court9155]

A stock mopar cast piston will start cracking at the wrist pin within 4 to 6 passes with a 400hp hit... Those didn't have a factory stl shim gasket though.
I would never do that with a hyper piston though

I have only pushed one head gasket out of a sb as the 2nd stg hit at 250 on top of the 1st stg and that was primarily because i forgot to add the additional head torque on a regular fel-pro gasket.

Then it will laugh at my 125hp shot.

Dan

 

[Supershafts]

Yes thats not a issue for the factory piston or gasket, as long as you don't run out of gas on the fuel side