Originally posted by chiphead:
Check my math, but wouldn't 15% be a fairly big increase in power for a 6 cylinder?
150 HP x 15% = 22.5 HP for 172.5 HP.
Not at all, chiphead. Done right, headers can provide as much as a 30% power boost. Here's a
LINK to a header manufacturer who claims a
minimum 14% gain in horsepower on a
stock engine.
Now the Porsche 928 is a well-designed, multi-valve, aluminum eight cylinder engine. A bone stock, cast iron, six cylinder Stovebolt would benefit even more from the freer breathing.