Vapor Lock Confirmation?

[GuysMonteSS]

At least it was a simple fix !!
Guy

 

[Pontiac455]

Good find mate. You should be proud of yourself. better than changing the cam and fuel pump..... lmao.

 

[Supercharged111]

Normally vapor lock occurs at low speed or after a hot soak, but not going down the hyway, I might suspect fuel pump is starting to crap out, getting any heat source away from fuel lines is a good idea. Some fuels do boil easier then others but on the pressure side of the pump you would think it wouldn't happen, do you have heat spacer under carb?

I got vapor lock in TX in the summer with my Edelbrock carb on the freeway. Typically though it would only do it on a hot restart. If I could have had a return line setup for that carb I think it would have killed the vapor lock.

 

[565bbchevy]

I use Jomar phenolic spacers under my carbs and have found them to be the best at isolating the carburetor from engine heat.

Phenolic Carburetor Spacers

Racers, street rodders, and anyone who wants to maximize an engine's performance, rely on JOMAR Phenolic Carburetor spacers. The advanced phenolic laminate transfers approximately ten times less heat to the carburetor resulting in cooler denser fuel/air mixtures. In addition, spacers are used to...

jomarperformance.com

 

[Supercharged111]

I use Jomar phenolic spacers under my carbs and have found them to be the best at isolating the carburetor from engine heat.

Phenolic Carburetor Spacers

Racers, street rodders, and anyone who wants to maximize an engine's performance, rely on JOMAR Phenolic Carburetor spacers. The advanced phenolic laminate transfers approximately ten times less heat to the carburetor resulting in cooler denser fuel/air mixtures. In addition, spacers are used to...

jomarperformance.com

I've long suspected this to be the solution to my old issues. Do you have a before/after comparison with such a spacer?

 

[565bbchevy]

I've long suspected this to be the solution to my old issues. Do you have a before/after comparison with such a spacer?

No temp gun comparison but my carb on my 565 went from too hot to touch to just warm.
In the past I have used aluminum heat shields (stacked plates and gaskets) , phenolic plastic and also wood spacers, while the wood spacers do work well they crack easily , absorb fuel and are not really machine able while the Jomar spacers can be easily machined without affecting strength and are not affected by fuel.

 

[Bonnewagon]

The best thing you can do to prevent vapor lock is what the factory did. Just use a recirculating system that sends excess fuel back to the gas tank. That way you always have a supply of fresh relatively cool fuel going to the carburetor at all times. Once you disable the return line then you are at the mercy of the hot fuel sitting in the fuel line between the pump and carb. Not only is that a very hot area but the fan is blasting hot radiator air at the line. Anyone who had an old VW bug knows just how easy it is to induce vapor lock with poor fuel line plumbing.