I have a 202 chris craft stinger. I am curently putting togather a 355ci chevy(400hp). I am just checking to see if this would be worth it since I see them alot, only on big boats..

Best return will be to put a 383 stroker kit in it.

Just curious why would the 383 be better then the 355?? Just because of more tq, the boat only weights about 1800 lbs..

It´s interesting to see how the extension box issue keeps coming up again and again.
Well my 25 Outlaw has now got 60 hours on it since I fitted the Imco box (with 3" raised x) and it show absolutely no handling or performance problems - and runs 81 mph on the same power (525) as Baja only quotes its boat to do 75 mph with!
Yes is does feel like a bigger more capable boat, reacting beautifullly to trim and steering inputs.
I´m totally happy with the convertion and a friend just put the same settup onto his 29 Aerotek (runining 900 hp) and is equally convinced.
Like KPM said - due to the angle of attack that a planing hull runs at, 12" back has to be accompanied by raising the x sufficiently.

How big is your pad on your boat? As I mentioned before in previous threads we have talked on before the 1 inch above stock combined with the 12" setback absolutely screwed up my boat and the 1 inch spacer got rid of 80% of the box created problems but slowed boat down even more. I think there is a direct relationship as to how the box reacts compared to true v-hulls and boats with pads on them,Smitty

I am in the process of building up a 24' P&D (Same hull as the Pantera 24)

It has a small pad similar to your Baja. However I am using an IMCO with a 3" rise. This will put the X at 20.5" (17.5+3). I am setting it up exactly a couple of Corsa's that competed against each other for a few years. Yes it will have long tabs.

Ok, my boat is a '93 Checkmate 230 Enforcer and it doesn't have a pad whatsoever..
21 feet of hull ..24° deadrise and a 7' beam....Propshaft 6.5" below the keel.

Do you think I could possibly benefit from an extension box??


Next question is.. would I have to raise the engine at all??


Thanks,

Doug

THE PAD ON THE 25 OL IS WIDER THAN MY 24 Ihave a 2'' shortie no box and picked up a lot of speed over stock

I have been told by several reputable sources AFTER installing my box with negative results that boxes work better on true v-hulls. I'm no expert however. I was able to use my stellings box in the plus 1" position with just very small changes in my engine position and was able to achieve about a 3 degree angle on the driveshaft. That put my prop1 inch higher than stock. It caused my boat to porpoise,blowout,cavitate and drive like crap in rough water. I was able to get rid of 80% of the ill effects by adding a 1"drive spacer but I lost speed from the box and lost more speed from the spacer. The box could be moved up another inch to achieve 2 inches above stock but motor would either have to be raised 1/2 inch to get 5 degrees of driveshaft angle or you would have a 7 1/2 degree angle which would be alot.I would be leary about moving drive back 1 foot on a 21 ft boat and up after my fiasco this summer but you could either find someone who did it on a similar hull as yours or just do it and see what happens,Smitty

heres some pics as installed it