The motor makes good torque but IMO the horsepower is on the low side for what the heads flow. I believe the combination of the shorter runner/smaller plenum intake and 1 5/8 step header may be why the numbers look like they do.
So now I have a larger primary tube header (1 7/8") which is around a 15% increase in primary tube volume. My feeble mind posits the theory that an increase in intake flow would only compliment the increase in volume on the exhaust side.
What happens when the intake charge goes through a smaller intake runner and into the chamber at fairly high velocity then gets pushed out to a 15% larger area? One would think it slows down because of the larger area. What I'm saying is that when you increase your overall volume on one side (either exhaust or intake) it would only make sense to do the same on the other side.
A lot! Hughes charges $220 for a "deep port match" which I've basically already done myself on the SD. Their next step up is $680 for their "competition porting" service.
Wilson is going to be WAY more expensive. I mean, they weld a plaque to your intake when they're done! In 2022 that kind of thing is not happening for under a grand.