Class 6100 rules are out on BITD

[FlyHiFlyLo]

vapor lock.... there is no such thing on an EFI engine. Do you have any idea what temp fuel will have to be at to vaporize at 36psi??? WAY OVER 300F....

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[sirhk100]

vapor lock.... there is no such thing on an EFI engine. Do you have any idea what temp fuel will have to be at to vaporize at 36psi??? WAY OVER 300F....

So in my case where I was simply cooling my fuel pump you think it was the pump over heating and not working?

[FlyHiFlyLo]

Here Jerry I will throw you a few bones here.

#1 make sure the return line from your regulator is one size SMALLER than your pressure line. If the line is the same size it may work MOST of the time. But you need to take in account for the fuel displaced in the rails and consumed by the engine. Otherwise what happens to the void in the return line? yeah that's right it will suck air from the tank to displace it.
#2 Something you didn't listen to.... Use the bypass side of the regulator as your return line. You have your crap is backwards according to how you discribed it..
#3 USE Pump gas.... that engine is designed and mapped for PUMP gas. Yeah Ethanol and all.

[FlyHiFlyLo]

So in my case where I was simply cooling my fuel pump you think it was the pump over heating and not working?

take an amp reading on it and compare to manufacture specs. If it's pulling too many amps then it could cause the pump to flutter.

[Robert Mason]

vapor lock.... there is no such thing on an EFI engine. Do you have any idea what temp fuel will have to be at to vaporize at 36psi??? WAY OVER 300F....

It boils the fuel before the pump not on the pressure side.

[OldGreen]

It boils in the tank and before the pumps. It also can boil in the return line. You should be able to hear the pumps cavitation.

I don't know if it is class legal or not, but maybe if somebody searches for "vapor lock" and "fuel injection" they will get a good answer here. We fixed the problem by modifying a fitting on the fuel rail to get "flow through" and regulating on the back side rather than keeping the dead end system. But, again, different rules. . .Just getting an air gap around the cell and getting it out of direct sunlight helps. It is really only an issue at V2R.

[FlyHiFlyLo]

It boils the fuel before the pump not on the pressure side.

Vapor rises...

[FlyHiFlyLo]

We fixed the problem by modifying a fitting on the fuel rail to get "flow through" and regulating on the back side rather than keeping the dead end system.

Exactly.

make it a loop.

[fishd00d]

vapor lock.... there is no such thing on an EFI engine. Do you have any idea what temp fuel will have to be at to vaporize at 36psi??? WAY OVER 300F....

RG had Vapor lock during qualifying....

[CRAIG_HALL]

If I'm not mistake the fuel enter rear of one rail, crosses over at front, thru other rail, exits at rear. there's a regulator on the exit right ? I'd have to check with Jason at shop to confirm..