Aftermarket/Replacement Cylinder Head Rule Change

[Dwight Southerland]

Bill Jenkins always said 10-12 HP. Chevrolet engineers said it helps more with higher compression ratio and dome in the combustion chamber, but that it was about 10 hp on flat top pistons (350 cu in, 10.5 compression). I have only seen an un-scientific test once on a 377 dirt track engine when a pair of ported 461 heads were replaced with unported 292 heads and the difference was 22 hp.
If high compression benefits more, then consider that all blueprinted 62-70 327 and 350 flattop pistons engines run between 11.5 to 12.0 compression.

[Jon Sarrett]

Originally Posted by Dwight Southerland

Yes. And both Stock a Super Stock rules are under constant attack for advantage. Edelbrock pn 60947 heads that were accepted last year for the SBC and the current Jones Engineering heads for SS are angle plug heads. Even though NHRA rules specifically state that the spark plug angles cannot be changed and NO Chevrolet small block V8 EVER came off an assembly line with angle plug heads. Can you imagine a 327-275hp engine in Stock Eliminator with angle plug aluminum heads??? Write your division director, the national tech department, the NHRA national techincal vice-president, the NHRA CEO, your mother and any one else you can think of to object. Such actions and decisions will destroy the eliminators faster than you can imagine.

Actually, LT-1 heads are angle plug.

[FED 387]

L-98 Corvette was an angle plug head too I believe---FED 387

[Dwight Southerland]

Originally Posted by Jon Sarrett

Actually, LT-1 heads are angle plug.

But the replacement heads listed are for 62-70 year models.NO angle plug heads during those years.

[Jim Hanig]

Originally Posted by Dwight Southerland

But the replacement heads listed are for 62-70 year models.NO angle plug heads during those years.

Dwight there never alum heads for 428,390 Ford's either,but they Got them now. Cant see how the heads for the chevys would make much diff.

[6130]

I'm still perceiving Stock Eliminator through 1980's glasses, because that's what I was most comfortable with. Headers, converter, ring & pinion, and a 9" tire...on a car with a VIN number. Not saying it's better or worse, just saying I'm somewhat stuck in that perceptual paradigm.

But whether I'm comfortable with it or not, Stock has moved on. Just like stock moved on from the '60s, to the '70s, to the '80s, all the way through today.

I still find Stock Eliminator fascinating, but it is more and more becoming a class that is difficult to explain to lay people, which I think hampers it's value as a financially viable spectator commodity.

Ultimately, I think that Stock is going to die, and when it does, I will very much miss it. It is (and was) a beautiful class.

[X-TECH MAN]

Originally Posted by 6130

Ultimately, I think that Stock is going to die, and when it does, I will very much miss it. It is (and was) a beautiful class.

Stock Elim. DIED in 1985 !

[Dwight Southerland]

Originally Posted by Jim Hanig

Dwight there never alum heads for 428,390 Ford's either,but they Got them now. Cant see how the heads for the chevys would make much diff.

Then NHRA's rules for Super Stock heads "Grinding and polishing in combustion chamber permitted. Welding and/or applying epoxy in combustion chamber prohibited. Spark-plug hole must maintain the stock location, size, and angle as machined by the OEM; spark-plug adapters prohibited." can just be ignored. Have you seen the combustion chambers on the Jones heads or the Edelbrock heads? I guess everybody is satisfied to be a frog in a pot with the fire on high.