What makes an HP525 an HP525?
 

OK,

An HP525 has 525hp right? Well, how does it get the extra 100hp over a 496 HO? I don't think it's supercharged. So how does it make the extra power? Cam? Heads? Intake?

More cubic inches,better heads,lumpier cam,better intake and a better fuel map.

From some of the dyno posts I've seen most make more than 525HP. Doug

really?

525hp EFI's make 525hp+ SAE all day long. They make 550hp corrected on almost everybody's dyno's.

The 496 engine is GM's new generation block, and is a very cheap motor, very close to auto OEM in every sense. The 525hp efi is a hand built older style GM engine. Has better internals (crank, rods, pistons, valves, push rods, springs....), far better flowing heads, much bigger camshaft, better exhaust, etc.

The computer is not "better", it's actually identical and the maps are done for their engines volumetric efficiency. Both have very good maps, slightly conservative, but very nice maps.

Thanks,
Dustin

dustin are you programming the 525 ecu yet a little more rpm would be nice and a better map if possible

525 is based on the 502 not the 496.
496vortec and 502 share almost nothing. two completely different beasts.

On the Crank or on the Prop, now I believe Merc lists them at the prop ?

yes he is !:rolleyes:

Cubic inches? I thought was still based on a 502?

The reason I ask is that I'm considering a Powerquest 280 that has a Precision Marine 502 that has been modified to run naturally aspirated with 540hp at the crank. I believe this is equivalent to a HP525's power. The power was made with Dart high flow aluminum head, ported and polished intake manifold, high flow exhaust manifold, and a different cam. ECM tuning as well of course.

Am I basically getting an HP525? If so, WOW!

Approx How Much more HP with the remap????

I believe he said 30-40hp more per side, but you have to run 91 octane. He can also raise the rev limit to 5850 safely.

Nice and definately something to consider. Thanks

525s range from 538 to 572HP i have seen on the dyno.

A 525 makes about 500 at the prop. Most will dyno, as JC mentioned, at least 540ish hp at the crank. Been done many a time. Most loose about 10% hp once they make it to the prop via bravo. I dont think merc lists any motor at the prop b/c it doesnt tell anything. They make too many drives and motors that can be interchanged like a 525 with an XR, #6, and according to merc racing now an NXT. All those drives eat up different power.

I wonder who else can raise the rpm?