NHRA 2020 Rule Amendment SS Intakes???

[Tom Broome]

Originally Posted by SSDiv6

Get off the pipe. Your statement shows the lack of knowledge of porting cylinder heads.

It is not about volume, it is about CSA, volume and shape of the port. You can have a 230cc port volume that is outperformed by a 200cc port volume.

Well....He may not be a "renowned head porter", but he has enough common sense to understand that if you lose volume by drastically milling the intake surface, you gain the ability to change the "CSA, Volume and shape of the port".....To use your phraseology.

Perhaps you shouldn't take his statement as an absolute.

[SSDiv6]

Originally Posted by Tom Broome

Well....He may not be a "renowned head porter", but he has enough common sense to understand that if you lose volume by drastically milling the intake surface, you gain the ability to change the "CSA, Volume and shape of the port".....To use your phraseology.

Perhaps you shouldn't take his statement as an absolute.

Common sense?

As stated in a prior post, legally, Super Stock cylinder heads can be welded and/or epoxied. The angle milling does not have nothing to do with the volume of the ports. The majority of the Super Stock Chevy small block cylinder heads ports have been reshaped with epoxy and most are configured to an oval port from the OEM rectangular port shape.

Therefore, any Super Stock cylinder head can be returned to the appropriate port volume by welding or the use of epoxy.

[Dan Fahey]

Originally Posted by SSDiv6

Common sense?

As stated in a prior post, legally, Super Stock cylinder heads can be welded and/or epoxied. The angle milling does not have nothing to do with the volume of the ports. The majority of the Super Stock Chevy small block cylinder heads ports have been reshaped with epoxy and most are configured to an oval port from the OEM rectangular port shape.

Therefore, any Super Stock cylinder head can be returned to the appropriate port volume by welding or the use of epoxy.

This is what Bill Jenkins, Bob Glidden, al all the Early Pro Stockers did to their heads.

No wonder Stock and Super Stockers are running ET's that were State of the Art back then..

[Tom P]

I am curious why it's always been worded as "must hold volume" and no mention of maximum.

"Cylinder head must be able to hold combustion chamber, intake and exhaust runner volumes per NHRA Specifications"

The way I interpret that is a five gallon bucket will hold a gallon but a one gallon bucket won't hold five. So ports can be larger than their spec but not smaller.
Obviously they want the combustion chamber to hold all of the 72cc or whatever spec is but they want that 205cc port to hold NO MORE THAN 205cc.

Why wouldn't they just say that?

A lot of the rulebook seems to have been written in 1952 and they added extra words instead of rewriting the whole thing. The previously mentioned pinned studs for example.