Fuel pump size too big?

[banzaibullitt]

Will a 255 lph fuel pump have any adverse affects on a stock 1986 EFI 302 H.O., or will it be fine? Eventually I may go with aftermarket heads and 24-30 LB injectors.

[Haystack]

I saw a video where they cut open a fuel tank to show how badly it airiates the fuel with different sized fuel pumps. It was an eye opener.

Size the fuel pump to the fuel requirements. There are a ton of calculators out there. You don't need the biggest pump (or fuel injectors) if you arent making much power.

[FoxChassis]

I agree with above. Some say go as big as possible regardless of need. I say nonsense to that. Size according to need.

[banzaibullitt]

Good information. Thanks for the replies.

[banzaibullitt]

I saw a video where they cut open a fuel tank to show how badly it airiates the fuel with different sized fuel pumps. It was an eye opener.

Size the fuel pump to the fuel requirements. There are a ton of calculators out there. You don't need the biggest pump (or fuel injectors) if you arent making much power.

Do you have a link to this video?

[79mustang]

Pro-m has a video showing how bad a stock pickup areates fuel going back into the tank. Some say needlessly pumping unused fuel throughout your lines also causes un-necessary heat in the fuel.

[Zap's 85 GT]

You will also need to install an aftermarket fuel pressure regulator as the stock one can't cope with the extra fuel at idle. It will run rich and possibly surge at idle.

[banzaibullitt]

Would I need a different regulator if I only went with a 155LPH pump? I've never heard of having to change the regulator when changing the pump.

[banzaibullitt]

^^^Bump^^^

[erratic50]

the only thing the regulator does is regulate fuel pressure. The only time you need a different one is if you need to change fuel pressure for some reason such as a rich or lean condition with the stock tune, etc.

There are well established articles that discuss fuel pump capacity vs power output. Ideally you would only have a large enough pump to maintain fuel pressure at WOT and no larger.

255 is WAY too big for most setups anywhere near a stock HO.

If memory serves we put a 155 in my son's 1986 convertible when we installed the new fuel gauge pickup, etc. Its mostly stock but running a VM1 ECU. No intake silencer, K&N air filter, base timing advanced to "kill". It should be good to somewhere around 400 HP or so.

[banzaibullitt]

Ok. So I should be just fine with a 155lph.

[Ourobos]

I've ran 255 on bone stock setups, no issues other than a little louder.

[banzaibullitt]

I'm getting a 155lph pump. I don't know if mine is original or not, but it has always been pretty loud.