Just looking into other performance option and wonder if anyone has put a whipple on 496HO and even better a 288 sunsation and how does it fit under the hatch, seat ect:
Were than any issues to be aware of?

My simple advice! Do not put any supercharger or turbocharger on a stock 496 marine motor and expect any longevity out of the motor-Period!

Ray @ Raylar

boom ?

You're funny Ray...

there was a 288 sunsation with wipple for sale in the boat trader NC i think. here i found it.

http://adcache.boattraderonline.com/6/6/3/79804763.htm

I helped a friend put one on his 25ft Eliminator XP 3 yaers ago and he hasn't had any problems with it. It probably has 100-150 hrs on it. We couldn't find anyone that had tried it on a 496 at the time, so we just went for it. As far as seat room we had to move his back seat forward 2 inches. From looking at the boat for sale, it looks like there is room.

Ray, I'm wondering what problems you see with the 496. I was worried about head gaskets, because I blew my 502 gaskets, but we didn't change them and there have been no problems. Crank, Rods, heads?

I think Ray might be referring to the top ring lan area. The OEM's to help pass emmissions have begun to move the top ring location up. This elimnates more of the area between the cylinder wall and the piston where unburnt gas is trapped and not burnt during the combustion cycle. By reducing this area the positive is that it reduces the amount of unburnt gases released into the exhaust stroke and out the tailpipe. The negative is that the crown area of the piston ring lan is very thin and can easily be destroyed in cases of detonation or extreme combustion pressure and temps. So when adding boost or NOS to these lastest generation engines you better have everything correct because just one small hick-up and your mill will be toast.

Chris

GM prematurely said before the 496's were launched to expect 500 HP and they would be direct replacements for the 502's. Stronger too.

Well they are very nice 375 HP and 425 HP engines...but they sure are not 502 replacements.

Thanks for the clarification Chris.
I haven't seen one of them apart, so it's nice to hear some good technical info about the engine. Ray I just hit your web site and see you sell replacement parts to rectify this problem, so when my buddies 496 go boom, I know where to get the parts from.

I'd take a 496 MAG HO over a 502 MAG any day of the week and twice on Sunday...if you are leaving them naturally aspirated. On the other hand, I'd take a 454 MAG MPI over a 496 MAG. Can't compare the 496's to the blue Merc motors as it wouldn't be apples to apples IMO.