Inliners International Forums General Discussion Hi Performance High Performance Mechanical Fuel Pump - 250

Hi guys, quick question. Is there such a thing as a high performance mechanical fuel pump for a Chevrolet 250? Is it necessary for a mild build (intake, headers, cam, etc)? If not, what brand should I get for an OEM replacement? Thank you.

I saw somewhere that a hipo V8 pump could be adapted to an inline by changing the arm. Do a Google search and it will probably turn up, or somebody else may chime in with a more definitive description.

I used to live in Florida where it got pretty hot during the summer, and if my car (stock 230 engine) sat for just 2 days, the fuel bowl would be too low or empty to fire up right away. It took a little too long to start the engine, for my liking. I installed an electric pump, it primes the carb in seconds, and fires right up after that. Never going back to a mechanical pump.

So far I haven't seen the need: Offy intake, Holley 390 and Langdon headers. Haven't done a cam yet or intake manifold work but I'm just fine with the fuel.

I have never run out of fuel with stock pumps on my sixes. I'm not racing, street only.

Two more quick questions:

- What is the difference between the mechanical pump that has threaded inlets & outlets, and the pumps that have the cheesy 90-degree barb fitting?

- Most of the mechanical pumps for sale state an operating pressure of about 4psi, Holley states the minimum for a 390 is 5psi. Can someone expand on this please?

Thank you.

A stock fuel pump has always been just fine for the Holley 390 on my 250. However, I had to replace stock fuel pumps pretty regularly, and they never seem to fail while in the driveway, lol. I suspect they failed due to regular runs up to 5-6,000 RPM which they weren't designed for. I switched to an electric pump and never had a problem after that.

I picked this up along the way....

This setup is also what I did...Just some more good info on mechanical fuel pumps... if you want to run a 4bbl or double pumper you should run the fuel pump off of a 1984 L6 250 which had a base pressure of 6­8psi instead of the 4­6psi of all earlier L6 250 mechanical pumps. As well boost referenced mechanical pumps are good to 12­14lbs of boost after that, they cant keep up.

You don't run any more then 6psi to a holley.