vapor lock

[95shaw]

sport mod 500 2 barrel. on restarts would act like running out of fuel at end of straights for first lap then fine. is this vapor lock? what would you do to stop this. Running premium pump gas for the first time. air temp 95+ engine 210.

[95shaw]

sport mod 500 2 barrel. on restarts would act like running out of fuel at end of straights for first lap then fine. is this vapor lock? what would you do to stop this. Running premium pump gas for the first time. air temp 95+ engine 210.

Actually caught what was happening while setting timing after heat race. would idle fine. After opening throttle to raise rpm, needle valve would open and a huge geiser for air/fuel woulld blow out of the vent. after engine cooled, this was not a problem. reset float level lower. Still did this on restarts for feature.
Apparantly, my no alcohol premium fuel source is not accurate. or is there something else i can be doing to prevent this?

[QQQQ]

Whats your fuel pressure?

[stock car driver]

how many gallon per hour pump? what rpm?

[95shaw]

carter m4891 120 gph. have used these pumps for years w no issues. replaced pump after first problem. still same. turn 66-6800 rpm. only have had issues on restarts. really believe fuel is boiling in lines. goinig to drain fuel tank a switch suppliers to find if this is the issue.

[stock car driver]

That pump didn't flow enough for me to run a 10-1 355 with 4412. It went lean at high rpm.

[95shaw]

What pump would you reccomend?

[stock car driver]

I had a bunch of pumps when this happened. I had what you have, 110120,130 and 170gph pumps.. I had thought they were all about the same. I had the issue with the 130.

I would recommend a 170gph.

I liked the holley billet 11-327-25 pump.

Carter makes one cheaper than the holley now with the same specs.

My issue plagued me for weeks. I would run hot some nights almost instantly and great other whole nights. I finally figured out I had all those different rated pumps thanks to talking with my carb guy about it.

[95shaw]

Din you run a regulator or return line with this pump. some recommend one some do not.

[stock car driver]

No regulator or return line is needed with that pump. It worked great for me without and I have a few customers Ive sold carbs to running that pump also now. Its owner rebuildable so the price is steep when you buy the first one but it should be the last pump you ever buy.