Super stock head porting
 

Does anyone recall what year NHRA allowed porting and then chamber modification in Superstock? Thanks

Re: Super stock head porting
 

They allowed it long before it actually became legal by the rule. Porting and covering it up with blasting and acid was common before it was legal by the rule. Mid to late 80's would be my recollection on porting. Chamber mods came after that as a separate modification t the rules. Early on there was no port CC size and the ports were not poured during a tear down inspection.

Re: Super stock head porting
 

Chamber mod was the start of 2004 I recall at Jegs race in 03 they were taking pics of all the SS chambers.

Re: Super stock head porting
 

I've heard they keep a scrapbook titled "Photos of cheating we FINALLY had to acknowledge (after YEARS of having it blatantly going on right under our noses), but still did nothing about at the time, instead taking the path of least resistance and just making the cheating legal".

Re: Super stock head porting
 

Porting for SS was first in the rulebooks in 1990. Port volumes were published and enforced way before that. When Chevrolet cast up the replacement 291 big block heads in 1987, the as-cast exhaust ports were bigger than the NHRA specs for the original production versions and several racers had problems with tech until NHRA changed their spec.