496 - disappointing Dyno numbers?

[Bbc72]

Had my Nova on the dyno last week and am a little disappointed in the numbers. It produced 430hp @ 5600rpm and 440tq @ 4700rpm at the wheels.



Don’t get me wrong, the car is very fast and drives great, but I thought this combination would produce 500 at the wheels no problem after reading many threads of guys with similar setups.

It is a street car only, hence the oval port heads and camshaft choice. Wondering what you guys think of the build and what, if anything, is holding me back.

Specs:
496ci, 10.5:1
AFR 265 oval port heads – 112cc chamber, cnc ported option
AFR magnum dual plane intake – these come port matched to the heads
2 inch long tube Doug’s Headers. Rest of exhaust is 3 inch
Clay Smith 296/296 hydraulic roller cam – actual duration 237 / 237, 109 lsa
Holley Sniper Xflow tbi – they don’t make this particular model anymore, but it is equivalent to a 900cfm carb and supposedly supports up to 800hp
Sniper Hyperspark distributor, ignition box, coil
T400 trans, 2800 stall, 3.73 rear end
Car was tuned by a knowledgeable and reputable tuner


Appreciate any insights you may have!