Fuel Perculation Problem

[Steve C.]

I understand an effective way to deal with fuel Perculation is to add a Phonelic spacer. Does anyone know where I can find a 1/4" spacer for a 59 283 with dual Carter WCFBs?

[William C.]

Re: Fuel Perculation Problem

Not sure there is space under the hood for your spacer, better check before installing.

[Steve C.]

Re: Fuel Perculation Problem

Bill,

Thanks for the alert. I put a wad of tin foil on the air cleaner and let the hood drop, looks like I may have 3/4". May have to change out the wing nuts holding the cleaner on!!!

[William C.]

Re: Fuel Perculation Problem

Problem will be more at the outer edge than the center, remember to check that, and allow for engine bounce/rock.

[Clem Z.]

Re: Fuel Perculation Problem

block the exhaust heat riser crossover in the intake manifold. also wire open the heat riser valve

[Steve C.]

Re: Fuel Perculation Problem

Clem,

Thanks for the help. Will follow your advise.

[Clem Z.]

Re: Fuel Perculation Problem

Clem,

Thanks for the help. Will follow your advise.

if you drain down the rad you can just loosen all the intake bolts and slip a piece of .005 thick stainless steel shim stock in between the 2 center intake bolts. use a spare intake gasket to get the size of the shim stock you need. i always bent a 90 degree by 1/8" lip on one end if the shim stock so it could not slip in too far.

[George J.]

Re: Fuel Perculation Problem

Have you tried different brands, and octanes of gas?

George

[Duke W.]

Re: Fuel Perculation Problem

That won't make any difference. Strict "formulations" required by the EPA and CARB result in the same distillation curves, regardless of brand.

In fact, in all parts of the country every "brand" probably comes from as little as one to no more than a handful of refineries and distributors. The refinery gasoline is designed for blending with ethanol to achieve required vapor pressure and octane characteristics. In California it's called CARBOB - California Reformulated Blendstock for Oxygenate Blending.

The ethanol is blended at the distribution point when the fuel is loaded into the truck for delivery to the retailer. There are some differences in additives, like detergents, that are blended in at this time depending on the "brand", but for all practical purposes, gasoline, like engine oil, is a generic product.

Duke

[George J.]

Re: Fuel Perculation Problem

Duke,
I know that's what is said. I am not convinced that there is not a difference, though. I swithced from Sunoco to Shell about ten years ago, and the '65 definitely ran differently. To me, it's a cheap test. It may not make any difference, but I try the low hanging fruit first.

George

[Duke W.]

Re: Fuel Perculation Problem

Maybe ten years ago there was still some meaningful difference between brands, but a lot has changed since then - primarily more regulatory control of vapor pressure and ethanol content, which is why, today, at any given location in the country all brands of gasoline are essentially the same at any time during the year.

Duke

[John H.]

Re: Fuel Perculation Problem

Duke,
I know that's what is said. I am not convinced that there is not a difference, though. I swithced from Sunoco to Shell about ten years ago, and the '65 definitely ran differently. To me, it's a cheap test. It may not make any difference, but I try the low hanging fruit first.

George

George -

Any gas you buy in the Detroit metro area these days comes from the Marathon refinery/terminal just off I-75 in Melvindale; it's the only refinery in the whole state. Points further north are served by commodity pipelines from Indiana. Ethanol and any brand-specific additives are added when the tanker trucks are loaded at the wholesale terminal.

[George J.]

Re: Fuel Perculation Problem

George -

Any gas you buy in the Detroit metro area these days comes from the Marathon refinery/terminal just off I-75 in Melvindale; it's the only refinery in the whole state. Points further north are served by commodity pipelines from Indiana. Ethanol and any brand-specific additives are added when the tanker trucks are loaded at the wholesale terminal.

John,
yes, I've even done some work there. I am still not convinced that the additives, or whatever, don't make a difference in the way the gas(es) make the cars run. Who's to say that the name brands don't have less ethanol, or that it's more accurately blended. It would surprise me more that all gas is exactly the same, than if there would be differences with mixtures, handling, water in tanks, etc.

George

[Stuart F.]

Re: Fuel Perculation Problem

There are a number of after market speed equipment outfits that handle spacers of different thicknesses, and not all of them are made of a phenolic material. Reason I mention that is I don't believe any are made specific to your application. You'll find some that will work well under a WCFB, but they won't have the cross cut from one front barrel diagonally to the opposite side rear barrel to match that in the Corvette manifold. Back in the day, I ran five (5) -1/4" spacers under each carb that were made of a fiber board type material, and I cross cut each one to match the manifold. With the extra added manifold area, the design deficiency of the Corvette manifold was corrected that allowed two cylinders to run lean. We learned this quite by accident while running a 270 hp engine without the exhaust manifolds on (just goofing around) and noticed the flame colors showed a leaner mixture on two cylinders. Using the spacers with the cross cuts eliminated that. Of course, the engine was being run in a 57 Bel Air Chevy Post which had lots of hood clearance.

Stu Fox

[Philip P.]

Re: Fuel Perculation Problem

How about trying non ethanol fuel?