A young guy who involved in OE engine parts for 7 years, sold his building, rent a apartment, live with his wife and 2 years old baby. The money was invested in casting and CNC machines which is same as the former OE factory. The quality is this young guy's face and future. They have no sense of how to make cheap aftermarket heads. Such as T6 heat treatment could be 5 hours or 3 hours, the hardness could be same, it was not what casting standard told me, it was a aftermarket casting guy told me. I don't think Promaxx or Sidewinder heads need to shoot at Stealth head. Stealth head was casting from one factory, machining by another factory. I know these two factory people since 2010. If you put Promaxx or Sidewinder head with Stealth head, you will make the decision in a half second. The Mopar heads need some fresh blood to let people know the heads could be better done.
Quote:
We recently did a maxed out full port on the Sidewinders ( same head I believe) and the results were right at 313 CFM intake on a Very correct , calibrated, stingy bench.
I am sure as time rolls on and more heads are whittled on that it will get better but honest, this is a street strip head not intended to go toe to toe with Victors, Indys etc
It is designed to be an Edelbrock killer and I guess you need a "Sidewinder" to shoot at Stealths?
So far---I have done several strong street engines with these heads --ZERO issues--I love the casting quality and the seats and guides are some of the best on the market --ports are more equal on these than other brands as well.
We have a regular old 440 flat top headed to the dyno soon with a set and a hyd cam so will report.
I love the quality for the $$ and feel like they are the best answer out there for a street/strip big block--way less than Edelbrocks and IMO better overall quality than everything else.
Want to race hard and go really fast? Sure, there are better choices but these heads will do anything an Edelbrock Performer head can for LESS $$ and at 313 CFM--Surprise many a bracket racer!!
Now...spending the loot it takes to get 313 CFM range--on a street head? Well... that is up to the individual, and a real race head may be better choice but...the heads are VERY capable of some Serious HP!
So far....I LOVE these heads! 
