[Mark Shaw]

Yes, my 38 Buick Special stopped at just over 12,000' just above timberline while climbing Pikes Peak! I was not surprised. I could actually see bubbles in my fuel filter just ahead of the carb.

[Bob LIchty]

I inherited a 1948 Nash 600 from my aunt this summer. I remember my uncle having all sorts of vapor lock problems with this same car 30 years ago. I drove the car all this summer with out the slightest problem. The quality of todays fuels stink, but I can't figure why I am not having issues when my uncle did have problems back in the day in the same car with no modifications since.

[1950SuperBlueBuick]

No choice on fuel in central IL. All E10. Now there's talk of 15, 20 or even 30.
Vapor lock was minor in '07, worst in '08 and '09.
Have installed elec. fuel pump to help hot starts and get through some occasional stalling @ 50 MPH.
263 always had a slight ping under load... has become a loud knock recently.
Will retard to 3BTDC and see if that helps.
E30 will end stock carbed cars running I'm afraid.

[mrpushbutton]

Simplyconnected hit it right on the head

"In reality, many cases of so-called 'vapor lock' is nothing more than a loose fuel line connection, a clogged fuel filter, or rust - clogging the gas tank screen".

How in the world, with the extensive scientific staffs and labrotories that GM, Chrysler and even Ford maintained going back to the 1920s could such a folk-lore thing like "Vapor lock" exsist and these learned men, with their vast scientific facilities could not find this and cure it?
Most of the people I know in the hobby who ascribe to this faith have cars that are by and large original, they have not done much heavy mechanical work on them, which is a good thing, but there could be any number of rational age-related things wrong in the chain of the fuel system, the most likely of which is heat warpage of the two halves of the fuel pump castings. THAT is what "Vapor lock" is found to be. I have fixed it on more than a couple of cars.
Early V-8 Fords defy this, they were designed to heat-warp (oh, sorry "vapor lock") .
I have seen fuel bubble in the glass sediment bowls of engines, but noticed one thing: there was gas present, in its liquid form. I don't see a gas present, nor do I release pressure when the bail wire is removed and the glass bowl taken off.

[jaxops]

Yes, in the 56 Cadillac.
Yes, but only in the 56.

My other cars are all experiencing high engine temperatures, including my wifes 2001 MB.

[Dave@Moon]

Originally Posted by mrpushbutton

I have seen fuel bubble in the glass sediment bowls of engines, but noticed one thing: there was gas present, in its liquid form.

You don't have to boil the fuel completely to have an impact on engine performance. In my case in the Buick the fuel boiled enough to push the liquid stages past the system and through jets and any other weak point, eventually purging the entire fuel system north of the fuel pump. I never determined what was happening in the Falcon, but I did not notice the massive carbon fouling and crankcase fuel buildup that the Buick had. I guess it just matters where in the system the most heat is applied.

[mystarcollectorcar.com]

Yes-every year that you mentioned.2 years ago with a 56 Dodge flathead and last year with a 59 Plymouth 318 Poly.

The 318 problem is one I have to classify as neglect on my part because the fuel line was touching the exhaust manifold-for quite awhile because the line was rubbed to a shine.

This year it was in a 47 Dodge on a 90 degree day and a 56 Chevy 283-again on a 90 degree humid day.That same day I helped push a 52 Chevy custom with a 66 396 Chevy off the road - all vapor lock,same problem.

Here's a link to story my brother did on the 47 Dodge-he describes the vapor lock as part of the article.
MY STAR SPECIAL FEATURE-BACK TO THE 40S:1947 DODGE TEST DRIVE