I would sell the Hp500's. They are not blower engines. Too many horror stories with the bolt on stuff. Build some naturally aspirated 572's carb engines. Cheap, reliable and around 700-750hp on gas. Ateco engines has an article in the latest issue of Powerboat Magazine. Give him a call in Waukegan Illinois. 847-623-2737

Yea, what he said!!

He never said anything about blowers.....and the $30-35K would include the proceeds from selling the 500's so the budget for re-building them must be closer to $15-20K.

at least I think I have this right!

I would take your motors to Joey Griffin in Washington NC and have him build you some 600hp motors. You'll run on pump gas, and have perfect dock manners. Take your $30K and have LOTS left over.

Better yet - take him the boat and have him do all the work. He will keep your boat indoors while it is there. Need more work done, paint, fiberglass, Griffin does it all and his prices are resonable if not low.

So....correct me if I'm wrong...doesn't whipple have a near bullet proof "bolt on" for an HP500 base? The stock cam is not ideal for blower so the cam would be a nice upgrade, Crane 741 would be better for a 700hp goal. If the guy is only looking for 700hp you can't get much more bullet proof than a 502 with a blower turning slow and he could easily get to 800hp+ when he decides 700 isn't enough.... and still be reliable....speaking from experience...

A 572" is going to be ~17k per motor if its done right...used carbed HP500's only going to bring ~7500/each. Why not keep the base, change cams, drop on a blower, and not really ask too much of a 502 @700hp...?

I like NA too and have had 600"+ motors, but in this case the goal of 700hp is so, so easy to do with what he has for far less total investment...unless he just is set on going NA....

My 500's have new Dart intakes, New Iron Eagle Heads and a 731 cam plus CMI exhaust. I kept it very mild. Maybe keeping the base is a better deal. I'm starting to like the Whipple idea. What do you think I'll spend to put 2 of these on top? What other upgrades would/should need to be done & will these fit under the hatch without major mods? 38 top gun, non blower hatch.

Correct, I only have about $12000-15000 if I don't sell my motors.

wow, i hate to be a party-pooper
BUT
IMO<$15k to rework both engines to your power-goal along with building them right(and reliable for a while) from oil pump to carb with the install may be alittle on the conservative side; unless you boyz have some good connections.
In which case, I would really like to get hooked up on my next project.

The discussion started due to my motors being torn down to fix cam bearings. My engine shop took responsibility for this and is fixing this for me at no cost. I figured while they were apart I could easily stroke/upgrade/ect the motors... that's how this whole discussion started. It turned from stroking them and spending $10-12M to not stroking them, selling them as is (a pair of upgraded HP500's) taking that money + my $10-12M and spending it for 2 new motors. I'd still be out of pocket $10-12M but I was hoping to have more HP and = or grater reliability.

sorry for your misfortune, glad to hear the shop took responsibility and thank you for the clarification.
I was getting ready to go over my reciepts to see where I went wrong.

Best of luck with your project