bobl

I just finished getting a good dyno run on the Nordic with the Raylar kit. I got a peak of 492.7 HP at 5170 RPM and 515 ft. lbs. of Torque at 4400. This is at the prop shaft. So add about 30 for the drive and we're dead on where we should be. This is totally installed in the boat, even with the engine hatch closed. One of these days I'll test an engine on the stand and then retest it at the prop when it's installed. I bet you lose quite a bit of HP.

boatingbent

Kewl Bob!!!!!!!

Can`t wait to see my Boat tomorrow......


We are in Cleburne Tx right now for the night........Bout 150 miles to go

Harper220

I'm pretty sure the 496 HO is rated at 425 hp at the prop, so 492 - 425 = 67 hp. I'm a little confused? Raylar advertises his kit at 525 pshp which equates to a 100 hp gain.

Nordicflame

The 496HO dynos btween 420 and 425 at the crank according to Tyler Crockett and some others.

Just curious, where does Ray advertise 525 pshp?

Dave

bobl

I don't believe Merc rates their engines as prop shaft HP any more.

Harper220

http://www.boattest.com/engines/104/overview.aspx

This review states that the 496 ho is rated at 425 hp at the prop shaft. I also know the non-ho motor is rated at 375 hp to the prop.

So.... With this info, when you add the 100 hp Raylar kit, theoretically the 496 ho should pump out 525 hp to the prop.

bobl

So, you gonna believe what a test article states or what Mercury and dyno tests have shown? Merc rates them at the flywheel. They used to rate them at the prop, but they never produced what they claimed when dyno tested. Now all their ratings are at the flywheel. They have removed all referrences to prop shaft HP ratings. Check out their web site. Also, Raylar claims 525HP crankshaft HP, not the prop.

Harper220

In 2002 I bought a 496 ho takeout from Tyler Crockett that came with a dyno sheet. Peak hp at flywheel was 469. Knock out 25-30 for the outdrive and you have well over 425 hp to the prop. Just to complicate things a little more...

Nordicflame

Tyler, Dustin Whipple and Raylar have all tested this motor and have come up with 420-430 at the crank on the HO.

Tyler even shows the 426.9 cshp as the baseline in his CMI test results. Maybe you should call Tyler and see what you really recieved

Dave

Raylar

NordicFlame:

Your thread here seems as though you are upset, Chill dude! The 496Ho is Mercruiser engine not a Mercury Racing engne. GM powertrain supplies Mercruiser, Volvo, etc. with the same identical engine. The engine is rated at 42HP at the crankshaft, not at the propshaft as Mercury Racing meausres their horsepower. The HP525 Mercury Racing engine is rated at 525HP at the prop and on dynos it seems to produce about 550HP.I am curious what it would produce on Bob's propshaft dyno. Most of us in the industry have measured stock 496HO's at the crankshaft and the results seem to support GM's rating. I have not heard of anyone measuring a stock 496HO at the propshaft. The 496H0 would most likely produce about 390HP or so at the propshaft if it is measured on a calibrated propshaft dyno. Not to many of those around. I am sure that Bob's measurement of 492 or 493 at the propshaft on our kit was a good number based on his dyno, but without measuring a stock 496HO on Bob's dyno there is no way to measure a base comparison number under the same conditions. I understand Bob is a good friend of yours, perhaps you would be willing to get him a stock 496HO that he can run on his propshaft dyno.

Ray @ Raylar