mercruiser 3.7 carby

[aussie]

Has anyone on here got holley or a edelbrock carby on a 3.7 I have been doing a lot of research and it seems like boat engine are over carbureted

[spareparts]

they generally over carb engines to make up for poor manifold design. The factory engines came with 750 cfm Quadrajets(180, 488, 185, and 190). They are very forgiving carbs if they are set up right, with it being a spread port design, they don't give up any bottom end. The secondaries are vacuum operated so it won't bog the engine. I've had good luck with them and prefer them over holleys and carters on smaller cubic inch motors. If yo run a holley or Carter with your modified manifold, I'd use a 500-600 cfm and maybe space it up an inch(four hole spacer). You may want to get your engine guy to look at the floor in your manifold, it may need some turn radius added to keep the fuel from bouncing off the floor or adding some material to offset the enlarged plenum

[smokeonthewater]

I too would suggest a quadrajet.... Likely the most under appreciated carb in history.

[aussie]

Originally Posted by spareparts

they generally over carb engines to make up for poor manifold design. The factory engines came with 750 cfm Quadrajets(180, 488, 185, and 190). They are very forgiving carbs if they are set up right, with it being a spread port design, they don't give up any bottom end. The secondaries are vacuum operated so it won't bog the engine. I've had good luck with them and prefer them over holleys and carters on smaller cubic inch motors. If yo run a holley or Carter with your modified manifold, I'd use a 500-600 cfm and maybe space it up an inch(four hole spacer). You may want to get your engine guy to look at the floor in your manifold, it may need some turn radius added to keep the fuel from bouncing off the floor or adding some material to offset the enlarged plenum

thanks spare I will show him the intake it looks like fuel would pool there and it also looks like it has been welded in the floor do these manifolds corrode there ??????

[smokeonthewater]

yikes... 99.99% of the time welding is an attempt to repair a crack

[spareparts]

the 4 bbl manifolds had an oil cooler that was made into them(welded?) I never paid that much attention to them. If teh welds look factory, thats what they probably are

[smokeonthewater]

Originally Posted by spareparts

the 4 bbl manifolds had an oil cooler that was made into them(welded?) I never paid that much attention to them. If the welds look factory, that"s what they probably are

fingers crossed