92' merc. 5.0 2brrl carb to 4brrl.? HP

[alex3012red]

Trying to get more hp out of my 5.0 has anybody done the change. I have a bayliner 24'52 w/a 5.0 and alpha leg. its a heavy boat for the engine I've read on bolting on a 5.7. I'll try that when my 5.0 goes out. will it burn alot more fuel, I just want quicker plane time. and maybe a couple of mph.
I'am not sure what hp i have, and what will i gain with 4 brrl.(will try diff props too)
thanks to all.

 

[Bondo]

Re: 92' merc. 5.0 2brrl carb to 4brrl.? HP

Ayuh,...

The 350 is the Best way to get More power,... It'll burn about the same amount of Fuel...

Swapping a 4bbl. to your 5.0l will net about 20hp, maybe 30hp at Best...

 

[John_S]

Re: 92' merc. 5.0 2brrl carb to 4brrl.? HP

Yep, only about 20hp and you won't feel the difference in that boat. Save the money for a 350 vortec reman. That would bring you close to a 100hp increase at the prop, and a decent increase of torque, which is what that boat needs to get on plane.

 

[alex3012red]

Re: 92' merc. 5.0 2brrl carb to 4brrl.? HP

Does my 2brrl still work on the 5.7 or do i still need to buy the 4 brrl set up.

 

[Bondo]

Re: 92' merc. 5.0 2brrl carb to 4brrl.? HP

Does my 2brrl still work on the 5.7 or do i still need to buy the 4 brrl set up.

Ayuh,.. Sure it could work,...

But,...
If you're trying to build More Power,..?? Why would you want a 2bbl. Carb,..??

 

[JustJason]

Re: 92' merc. 5.0 2brrl carb to 4brrl.? HP

if your short term goal is to just get on plane quicker, think about going to a 4 bladed prop.

 

[John_S]

Re: 92' merc. 5.0 2brrl carb to 4brrl.? HP

The 5.0L 2brl is significantly different than the 5.7L 2brl. 35mm vs 43mm. Not worth reusing. Going to a 350 vortec would require a new intake anyway.

For prop suggestions, there are many people over at BaylinerOwnersClub, that run your exact boat. If you have your current prop brand/specs, wot rpms, and gps mph, many can also help in the prop forums here.

PS: I think that boat has tabs. If it has them, make sure they are in good working order and use them. If not, they would help you planing time, and staying on plane at lower speeds.

 

[alex3012red]

Re: 92' merc. 5.0 2brrl carb to 4brrl.? HP

thanks, I will try a four blade prop it currently has a 15x19 3 blade, I have a new 14 1/4 x 18 4 blade is that too small of a diameter. So back to basics i should start looking for a manifold and carb that will fit the 5.7 and maybe work of the 5.0? any suggestions should i look for a used original set up for the 5.7?

 

[dan t.]

Re: 92' merc. 5.0 2brrl carb to 4brrl.? HP

i have a 1992 bayliner 2452 with a 305 engine alpha leg, originaly came with a 2 bbl carb. I switched to a q jet, about the same milage if you stay out of the secondarys, far better hole shot. the leg is 1.65 ratio this was for 2bbl only, but it doesnt seem to make mutch difference, I have tried at least 8 different props, the one that works the best is a merc 16x16 wide blade with some added cup, cruise at 18 t0 20 knots ( gps) at 3600,wot 4200,I agree with the under power bit , am putting in a 350 this spring

 

[alex3012red]

Re: 92' merc. 5.0 2brrl carb to 4brrl.? HP

today, I took my carb out and apart to find out that it needed a kit. So I will put the kit in it tomorrow and try it out one more time. I took it out beacause it was flooding the engine and hard to start. when i took the top of the carb the diafram was in two pcs. everything else looks to be o.k also i did a compression test and they were 140 to 150 psi. my plugs were with alot of carbon and wet.

 

[chiefalen]

Re: 92' merc. 5.0 2brrl carb to 4brrl.? HP

http://forums.iboats.com/showthread.php?t=291317

This is the way to go for a 5.7 and all the externals will fit from your 5.0.