350hp 350
 

I don’t know if this is the right place to post or not but here goes.

i have a 2001 Crownline 225br with a 250hp 5.7 vortec engine. 2 barrel carb Alpha 1 1.5 ratio with a 17p merc racing rev4. Boat weighs about 4000 lbs. with straight through hull exhaust. tops out at 45 mph. I want 55-60. I don’t want a 383 stroker setup.

I’m thinking about doing a cam swap to a 270/276 marine comp cam, going to a thinner head gasket to raise compression a little, Edelbrock rpm air gap intake and a 650 4 barrel (1409?) carb.

Will this setup push me up to the 350-375 hp range.

I am not close to an engine guy but just a cam wont get you a 100 hp gain imo for sure !!!

Well that’s why I’m here to find is peoples opinions on what I will gain. Or what it’ll take to get me to the 350 hp range. I’m pretty sure I can go to a 4 barrel and get to 260, and a very basic cam and get 300. But what do I need to make my 250 5.7 a healthy 350hp?

To get a hundred HP gain your gonna need a top end minimum. New heads, intake, roller camshaft, at the minimum. The trick is going to be keeping it making enough torque to get the boat moving and the peak HP within the allowable RPM range of your short block. Call a few companies like E'brock, Trick Flow, etc and see what they have to say.

From my understanding, it is already a roller cam motor, and I thought the 096 heads were supposed to be good?

I doubt a 100hp will gain you 10-15 mph. More like 6-10mph if you are lucky.

Any decent cam will probably require new exhaust with long risers

Your engine has Vortec heads, so yeh, you’ll be right there for hp.

4bbl carb + intake will put you near /at 300hp.

Those doubting a near 100hp increase maybe didn’t notice he has 2bbl 250 hp engine and adding a 4bbl carb and intake too ?

I’m not sure going to the thin head gaskets will be worth it. Personally I’d stay with normal felpro’s w/stainless core.

stock vortec 350 with a good intake and a 4 barrel is around 325 those engines love to rev its very good right out of the box

When you say good intake and carb is the edelbrock rpm air gap good? What about the 1409 carb? Well this get me where I’m wanting to be? Paired with that 270 cam? Do you think that 270 cam will give me any chop at idle?

RPM air gap, roller rockers, and I used the 218 / 224* @ .050 cam and I think you can get very close to your 350 HP. I added Vortec heads because mine did not have them and gained 8 - 9 mph and ran 60 - 61 mph.