Are thick head gaskets legal for compression correction?

[jumbojimbo]

The 305 AS with 350 gaskets is should not be legal. The bigger bore gaskets may unshroud the valves a bit and increase low lit flow.

I have the customer that wants to make sure that his engine is under the limit . I advised that i expect it to be over by around 1.0 compression value. Stacked MLS gaskets can reduce that value to the legal limit.

I will have him send a letter and just put this together as is , as it has been run for 15 yrs.
If somebody on the board can respond with a valid answer ,it would be nice.
Thanks, MM

Clarify: Does the customer want to be under the limit or does the customer want to be legal?

To be under the limit, then go ahead and stack the gaskets and move on.

To be legal, you (or the customer) have to write a letter. It seems like a reasonable request is to have the wording changed to "Cylinder head gasket(s) may be replaced with any gasket(s) having at least the same total compressed thickness as stock."

Keeping in mind that someone may argue that milling the head down and then increasing the gasket thickness would be an advantage on some car(s) and therefore shouldn't be allowed. In which case it could be rejected. And then the answer to be legal is "new head". If this is the result then please do not come back here and whine about SCCA.

[Bill Miller]

Clarify: Does the customer want to be under the limit or does the customer want to be legal?

To be under the limit, then go ahead and stack the gaskets and move on.

To be legal, you (or the customer) have to write a letter. It seems like a reasonable request is to have the wording changed to "Cylinder head gasket(s) may be replaced with any gasket(s) having at least the same total compressed thickness as stock."

Keeping in mind that someone may argue that milling the head down and then increasing the gasket thickness would be an advantage on some car(s) and therefore shouldn't be allowed. In which case it could be rejected. And then the answer to be legal is "new head". If this is the result then please do not come back here and whine about SCCA.

No more calls please, we have a winner.

[Flyinglizard]

¨ It seems like a reasonable request is to have the wording changed to "Cylinder head gasket(s) may be replaced with any gasket(s) having at least the same total compressed thickness as stock."
Should include less than .100 total so as to keep my angle milled head shim out of play. Stacked stock style gaskets should be allowed for any car 20yrs or older.

[Greg Amy]

¨ It seems like a reasonable request is to have the wording changed to "Cylinder head gasket(s) may be replaced with any gasket(s) having at least the same total compressed thickness as stock."

That's a rule change, and a change in the basic philosophy of the class. Regardless of if/when the request is submitted, note that it cannot be approved prior to the 2015 racing season.

No one else is interested in the idea. If you want it, write your letter to the CRB and it will be considered.

GA