carb advice

[blues]

1979 23 ft sleekcraft day cruiser
original motor was chev 350 / 260 sterndrive
had to replace, best I could do , afford, was a good used ford 302/merc. still with 260 drive
top speed went from 50 mph to 40 , which I kind of expected.
at 40 mph wot, rpms are around 4100
prop is 14.5 x19P
I do not know the factory wot specs.for the 302
changing to a 14.5x17 prop may help?
more rpm, more speed,?
any advice or help, please,.
maybe in the future , I can upgrade to a 4 barrel carb,.
but, now just a little more speed top end, would help

 

[Silvertip]

Re: carb advice

Decreasing the pitch will bring the rpm up but whether or not you see a speed increase is a trial and error thing. It will definitely help hole shot. However, just because you turn the engine faster does not mean the boat goes faster -- remember, you decreased the pitch so it take less bite -- hence less forward travel. You might also want to check the gear ratios in the outdrive as there are probably differences because of the power differences in the two engines.

 

[blues]

Re: carb advice

I have decided to upgrade to a edelbrock 4 barrel marine carb and manifold,.
this seems to be the best way???

 

[blues]

Re: carb advice

ok,, scratch the four barrel carb, I just canceled that order, as today I tried a stainless prop, marked 14x20
and this boat really took off, fast to plane, and a top speed of 45 mph, @ 4000 rpm,
I never expected anything like this,..
maybe a differnt stainless prop would be even better,.
14.5x17 ???
this little ford 302 in a 23 foot sleek craft, almost equals that chev 350
all the expert s told me this cant be done.
from 260 HP with the 350 down to 188 HP with the ford 302. and only 5 MPH difference.
the prop and maybe the boat design, as the sleekcrafts were very sleek,

 

[Tail_Gunner]

Re: carb advice

Youi might want to take this subject to the I/O section, not all 302's are created equal,for instance that might be a HO 225 hp with roller cam's