Fuel systems for drag cars

Men aren’t the best at reading instructions but when we do we sometimes learn something. Not sure if this helps or no but I buy BG400 pumps for pennies on the dollar because they have issues with them. I grab them and rebuild them. Lol

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Yup. Unless the tank is almost empty it doesn’t do ****.

What the directions do not say is keep the return fuel away from the outlet to the pump. With a 3 gallon cell it’s hard to do. Barry forgot that in his instructions.

With a bigger cell or a bigger tank it makes zero difference. I know it’s in all the books and such so it must be true.

I burned right at 2 gallons a run. A bit more if someone dicked around or you get stuck at the ticket window waiting for 25 dudes to get their time slips then it would burn another 1/4 gallon.

In a 3 gallon cell never once did the return fuel affect the fuel to the pump.

A number 6 line at 55 psi blows a ton of fuel back into the tank. I had a hose fail on the dyno at about 8k. The return hose I mean. The amount of fuel returning to the tank is almost unbelievable.

In fact, after we cleaned up the mess I started looking for ways to slow the pump down at rpm because most MFI engines are over pumped.

Big rpm and MFI means you need at least 3 bypasses. And probably a fourth.

That’s how much fuel those pumps produce.