Carb Spacer & General Setup

[BigRodney]

Hi everyone. I have a question about what seems to me my questionable carburetor/intake manifold combination. This is in a jet boat, so not the normal setup. I have a Ford 351W marine engine set up to have power and torque at around 4200 RPM. It has an Edelbrock performer dual-plane square bore manifold and Holley marine version of the 4160 carb. It also has a one inch thick spacer that I don’t particularly care for and this sheet metal throttle cable holder that is wide-open.

So it goes manifold, gasket, one inch spacer, gasket, throttle cable holder, gasket, carburetor. So since the throttle cable holder is just a big open square hole the airflow can go wherever it wants between the carb and the spacer and the spacer has these big voids in it that don’t necessarily support the gasket either. My understanding is that the dual-plane intake manifold facilitates torque which is what you need in a jet boat, but with all this garbage in between I’m not sure it’s working properly, and I think the gaskets are just flapping around above and below the throttle cable holder. I need some suggestions on how to fix this mess. BTW, the spacer also has to have a port for the crankcase breather hose. Any advice is appreciated, thanks.



UPDATE: I ordered this throttle cable bracket to get that other one out of the equation. One less thing. Now I’m wondering if I can just buy a new base for my carb that has a port for the crankcase breather hose. Mine has a casting where one should be and I could drill it out & tap it, but if a new base isn’t too much I’d rather just get one. Thanks again. https://www.cpperformance.com/p-341-...rburetors.aspx

[Gaz64]

Hi Rodney. First thing I would do is replace that voided spacer with a solid one. The voids only invite gasket leaks.
You can drill one hole between a pair of barrels, front or rear doesn't matter.
Drill an appropriate hole size until your bit just breaks into the area between the barrels.
If you set up well, the breakout should be about even.
Then reassemble how you have it, and you won't have an further issues. Gary

[BigRodney]

Thanks Gary. I posted about replacing the throttle cable holder and I'm going to order a different spacer, but my post never showed up.

[Danny Cabral]

...but my post never showed up.

It's combined at the end of post #1 (see "UPDATE").

[BigRodney]

OK, thanks.
I ordered this throttle cable bracket. It should take that whole layer out of the equation: https://www.cpperformance.com/p-341-...rburetors.aspx
I ordered this spacer. I called them and they assured me that it's solid, no voids like the other one: https://www.summitracing.com/parts/trd-2584

[Gaz64]

Thanks Gary. I posted about replacing the throttle cable holder and I'm going to order a different spacer, but my post never showed up.

Ah yes, I understand now. Another thing is if you did stay with this open throttle bracket, I'd run single-plane gaskets, or cut out the "cross" in the center of the gasket, then a loose gasket can't break up and be swallowed by the engine. Gary