Can I upgrade to the Edelbrock 1409 carb?

[Nextelbuddy]

I have a mercruiser 5.7 originally was a two-barrel setup.. The previous owner has upgraded to what appears to be an Edelbrock intake manifold and a four-barrel carb.

I I looked at the numbers on the side of the carburetor looks like it says Rochester 17080565 2431

It's really weird there's leftover wires near the carburetor which I assume are for the electric choke that used to be on the old two-barrel carb but I guess when they upgraded to the four-barrel Rochester it was a manual choke because there's this long choke cable that goes all the way to the driver's seat and I have to pull it open to start the engine which just seems really janky.

I don't see any numbers on the intake manifold all it says is Edelbrock performer but I don't know if it's marine specific.

I did a lot of searching on this forum and there were people saying that if you try to change from the Rochester to the Edelbrock 1409 that you'll have a problem with fuel fittings compatibility? and also people were saying that the Rochester is a spread bore and the Edelbrock is square...I'm assuming if I'm running the Edelbrock intake manifold already with the Rochester setup it either already has an adapter plate or the Edelbrock has two sets of holes to accommodate spread or square setup


I'm hoping if I post some pictures and obviously the model numbers of my setup pieces maybe somebody can nudge me in the right direction.

 

[gm280]

First question, what is wrong with your present setup to warrant a different carb? Are you looking for more top end, or better idle, or even better fuel economy? If there is a problem, that is one issue. But if you are looking for most anything else, not too sure you're going to find it. JMHO Let us know what reason for a different carb and we can better help.

 

[Rick Stephens]

I would figure out a way to install an electric choke....

Other than that - do you run in salt water at all? That is a major consideration on which model Performa. Edelbrock makes a marine version that has brass water passages. The standard Performa is all aluminum and won't last long in salt water.

The fuel line looks hand bent to me anyway, so swapping it would not be a big deal. I bought the OEM Mercruiser stainless fuel line when I installed a 1409 on a V6. The 1409 is identical carburetor to the OEM Weber carburetor, so if there was a fuel line that is listed for the Weber it will fit a 1409 as long as the fuel pump is stock.

I think the Performa will be square bore so that isn't an issue.

 

[Lou C]

I’ve seen a number of marine Quadrajets but none with an electric choke; all have had the divorced style choke with the thermostatic spring on the intake manifold. That works fine but only on the pre Vortec engines with the exhaust crossover. If the engine runs well and you get the hang of using a manual choke why change it, a Quadrajet in good shape is an excellent carb. You can of course install an Edelbrock but if you buy new it’s going to cost you $400 or so by the time you get done with all the little details.

 

[Lou C]

Ps there are electric choke conversions out there for Quadrajets that will work on the pre Vortec style intakes not sure it it would work on a Vortec style intake. Yours looks like a pre Vortec. BTW Merc also used Quadrajets till about ‘89 or so....