Originally Posted by SSDiv6
This posting is to allow some rational and logical discussion on the use of, and the market availability of aluminum aftermarket cylinder heads for the Super Stock class. I would also like to ask to please refrain the personal attacks and non-sense arguments in the discussion.
On this subject, I do not have a vested interest either. I have been asked by several race engine builders and cylinder head shops to assist them in getting an aftermarket aluminum cylinder head approved by NHRA for Super Stock class use only!
As we all are aware, NHRA has approved several makes of both cast iron and aluminum for use in the classes. However, with the acquisition of aftermarket and racing product companies by conglomerates, they have changed the business model from hard-core racing to bringing out products for late-model vehicles only. Edelbrock was for some time, the main supplier of cylinder heads and intake manifolds for the class. Another example is the Edelbrock SBC Victor “E” intake manifold which has been discontinued also.
However, after being acquired by a group of investors, the bean counters changed the business model, with emphasis on the Chevy LS/LT, Ford Coyote, and Mopar Hemi platforms. I confirmed this at last year’s PRI Show in a conversation with Edelbrock’s Program Manager Director for the cylinder head product line. Nevertheless, every time someone calls the NHRA Glendora office, they hear the same story…Edelbrock will have cylinder heads available next month and has been stating the same narrative since last year. The truth is that my job requires me to travel to Olive Branch, Mississippi twice a month and my employer owns a distribution center a few miles away from Edelbrock. Each and every time I stop to ask about their status, they do not have an idea because it is not in their schedule. When I confronted Glendora on the subject, they did not have an answer.
Last year I submitted several aluminum cylinder head options from various manufacturers that could have easily met the requirements for a Super Stock cylinder head and all were rejected for one reason or another. The rationalizing for the rejection from a technical standpoint did not make sense either. Their narrative did not even concur with what they believed they had approved. As an example, they claimed the Edelbrock SBC-approved cylinder head casting has a 170cc intake volume when in reality, it is 180cc. Moreover, the Performer RPM casting that the cylinder head casting is based on, the intake to exhaust valve centerline spacing is wider and does not match the OEM spacing. The reason for the wider spacing is for allowing bigger valves. As a matter of fact, when you order custom pistons for your Super Stock SBC, make sure to let them know you are using the Edelbrock cylinder heads so they can machine the valve notches to the proper location.
My last effort was to submit the SBC Profiler 176-X-CORE, Porter's cylinder head casting for approval. Technically, this would have been an ideal cylinder head casting for Chevy Small Block racers due to the fact the ports are small, allowing the development of an intake or exhaust port that would not require welding and/or epoxy. Also, no pushrod holes and the valve seat and throat are small enough that would not require welding for the installation of small seats for smaller valves. The cylinder head also has the OEM intake to exhaust valve centerline spacing. The elimination of extensive welding of the cylinder head, having the welded casting treated, and not worrying about distortion, is also a money saver. The casting price is also way lower than the Edelbrock, available and made in the USA.
After much effort, including submitting technical data and a sample of the cylinder head, NHRA also rejected the Profiler cylinder head. They also said that SRAC also rejected the cylinder head, which I would like to know in this open forum if they did or not, and their reasoning.
For those that may say that this would have been only good for the Chevy racers if this cylinder head casting would have been approved, Profiler would have been eager to have castings also available for other engine makes also. Having a “Porter’s” casting is cost-effective for a manufacturer since they do not need to install seats, guides, or drill pushrod holes.
This said, the parts availability issue is worrisome and will get worse.
Either NHRA wants racers to build late-model cars or electric cars, or the class to disappear.
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