Anyone know Holley Commander 950's? programming?

BillGrissom said

Re the fuel pump, you should have read my posts first. I originally put mine back there in my C-body (where there is much more room than an A). Now all my EFI pumps are in the engine bay. Works fine, easy access, and stays clean. Don't belief the instructions in the Holley manuals that you must mount in the rear, below the tank. I am a mechanical engineer, so allowed to think for myself. I bet you will hear the fuel pump real well thru that frame rail.

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I'm no engineer but I have been installing and running EFI for the last 14yrs.
The pumps that are used for EFI are made for pushing fuel not lifting or drawing fuel.
So they work best mounted as close to the tank and as low as possible. This allow the fuel to syphon feed to the pump so it does not need to lift the fuel before pumping it.

Having it mounted in the engine compartment can also lead to excess heat and possible vapor lock.
Yes EFI can still get vapor lock.

So while there are lots of things people get away with and then say it works fine, it doesn't always mean it's the correct way to do it.
Nothing is more frustrating than being stuck on the side of the road trying to cool off the fuel lines and pump so you can start the engine again.


If a pump is noisy then it's either a very cheap pump like to old Holley EFI pumps or you have a restricted return line.
V8s should run 3/8 inlet and 5/16 return. Limit the number of connections. The universal 3/8 brake lines work good and have flares on the ends.
Use rubber insulated adel clamps.


My $.02