More NHRA horsepower factors

[TommyPettigrew3076]

The 350 Chevy deal makes no sense I had a very long conversation with NHRA about it and got no where but the same answere " They are NOT identical Blue Print specs " so they are rated differently. The only problem with their logic or should I say lack there of is they may not be( EXACTLY) the same BUT the 77 and 78 share intake and head casting numbers that are an option one being the 249 cast intake and the 450 head can be used on BOTH combos . Now I am not the head cashier at Walmart but common sense would tell me if BOTH casting numbers can be used on both the 77 and 78 350 would't they be deemed the same if the 881,882,450 head on the 77 combo is rated at 269hp would the 78 350 be the same if it can also use the 450 head ? Now I would told that the 450 head has a 165cc intake runner and the 881,882 has a 160 cc intake runner so it is rated less? If this is the case then the 450 head would be deemed better and not be allowed on the 77 350 combo ? Am I crazy ? Now I was also told the 78 350 can use the 520 intake which is an aluminum one and it can use the 249 the cast intake so that changed the rating as well ? Ok well if that was the case and the aluminum intake is the better intake ( 14 hp ) better ( rolling eyes ) then why would the 249 cast intake even be an option ?

[Billy Nees]

Originally Posted by PJ305

I asked Pat Cvengros and was told the 78 models came with an aluminum 458520 manifold which aren't allowed on the 77 models.

Very interesting! And yet he allows an Edelbrock LD4B dual plane aluminum intake on a 273 that only had an iron single plane intake manifold.

[TommyPettigrew3076]

Apparently the cast iron intake flows better in different body styles lol