Looking for some thoughts here, I have a 252 Islander 502 Mag side mount whipple with about 280 hours currently, been running this set up for about three years. Boat will currently run 70-72 GPS depending on conditions and load. If i were to swap out the 502 for a 496 HO any idea on speed? I would like to stay north of 65 mph but dont know if thats possible with 425hp. And any ideas on what a fair price would be for my 502 & Whipple?

Not sure I follow.... you want to change it out for a stock powerplant? I think considering the economy, you'll end up with a slower boat that will cost a few bucks to change!

You will go from a motor (502) with forged internal parts to a motor with cast (496) internal parts...this is not a good idea and I will bet the boat wont run 65 with the 496 in it. You will be light years ahead to pull the whipple and sell it, then use the money to rebuild the 502 the way you want it.

What would the whipple be worth? Paul we actually exchanged "PM's" several times over on TBM about my motor, what would a ballpark estimate be to build the 502 to around 550-600 hp and keep it reliable?

If you build your 502 to 600 hp, plan on upgrading you bravo 1 to a XR drive.

I have no idea what the whipple would be worth (sorry) as I dont ever deal with superchargers. I would not attempt to rebuild your 502 as a 502. It would be mandatory with me to bore it .030 and make a 509 out of it. I would use the block, crank and heads...then toss everything else. The money spent rebuilding the stock rods could easily be used to get a set of Manley H-beam rods. I dont see it running over $7500.00 and this should cover everything from boring, line check, decking, heads and new parts. I am doing a 502 to a 509 right now and I think there is about $7000.00 in it with all top notch goodies...including a custom grind roller cam and this motor should be at around 625 hp. It will be very reliable. Talk to Watts Up on TBM...he has had one of my motors for about 16 months now and it is making over 650hp. As for your drive...as long as you dont hammer it out of the hole...you should be ok. Ron...my best bud has one of my 540's in his Islander. It made 758 HP at 6500 rpm and where the HP and torque crossed at 5300 rpm...the motor was making over 700 in HP and torque. This motor has been in his boat 3-1/2 years with nothing done to it but oil changes and spark plugs and he is still running the original bravo 1. But he never hammers it. Always eases in the power. The reliability issue solely depends on how you run it and this goes for anyones motor. No one builds a motor that cant be tore up.

Thanks Paul I will keep all that in mind as i decided what to do next, I am trying ot deceide if I want to sell the entire boat and move up to a 28 footer. The Bravo 1 drive was beefed up for the supercharger so I would think I would be o.k. from a drive standpoint If i continue to take good care of it.

I'd consider your supercharger if you were interested in selling. Let me know