Aluminum Intake Manifold & Electrolysis

Gents:

I'm looking at installing the Edelbrock Performer Intake Manifold on my 1994 Pro Boss High Output engine. The manifold is made of aluminum, and per Edelbrock: "if you use this in a marine environment, you have the possibility of having electrolysis in your cooling system, which can shorten the life of the intake manifold. Even if you use this in fresh water, you sill have a chance of getting electrolysis."

How many of you run aluminum manifolds on your engines? Any issues so far with electrolysis?

I'm looking at manifold # 2181. Any suggestions or recommendations? Would you consider the RPM version (#7581) or the 2181?

Thanks,

JQ

Tim:

Would you delete the spacer between manifold and carb to reduce the height? The QuickFuel unit I'm running has a rear vacuum port that I can use for the PCV.

Hopefully, that will give me enough room for the new manifold. I'm going to run the "squish test" by taking a small ball of modeling clay and placing it on top of the flame arrestor and then closing the engine cover. The will let me know how much space I have to work with.

JQ

Do they actually use the word "electrolysis" in their publication? Petes head is gonna explode.

They also make a marine rated unit with brass inserts in the water jackets. It may help in sweet water but useless in salt for belaying GALVANIC CORROSION. Pretty sure there are old aluminum exhaust manifolds out there running for generations in lake water.

Well, the clay "squish ball test" shows that I have 2 1/4" to 2 1/2" clearance between the top of the current flame supressor and the dog-house engine cover.

I believe that I'll have room for the Performer and maybe even the RPM. If the RPM was a bit too high, would ditching the spacer be a good trade-off for using the Performer RPM vs. standard Performer?

JQ

I'm just finishing up my '81 SN, which I bought with a very rough engine.
I rebuilt it, and am using not only an Edelbrock Performer manifold, but also Edelbrock (aluminum) cylinder heads, an aluminum timing cover and water pump housing, and aluminum exhaust manifolds.
I do not foresee any galvanic corrosion issues running in fresh water and draining after use.

Thanks, it sounds very crisp.
No, I didn't go roller, I reused the original RH cam, with a good polishing, and new stock lifters. Haven't run the boat (soon), stay tuned....

I have the performer RPM on my 94 with the spacer... the flame arrestor bolt squishes into the insulation on the top of the dog house, but it rides fine.   YMMV with your alignment and engine height though.   Make sure you don't forget the "plate" between the intake and the spacer if you do decide to keep the spacer. (intake, gasket, plate, gasket, spacer, gasket, carb)    I had a gasket failure this summer as I was not running the plate under the spacer. I was glad it was at the end of the day, but still a bummer to drag home a broken boat.

I just finished with the install of the Edelbrock Performer RPM manifold. To address the potential electrolysis issue, I installed a pencil zinc anode on a brass cap. You can see the brass cap on the last photo.







Cheers,

JQ

Looks great! Hoping you see some noticeable performance differences

Has anyone tried one of these to help combat electrolysis?