Speed Density - EFI To Carb swap over/ fuel system questions....

[@whiplashmachine]

I have three EFI vehicals I've swapped to carbed. I prefere using mechanical pumps though. In all the years I have been involved in engimes and racing, I have replaced out way more electric pumps than mechanicals. Just my preference.

[@sbf_fox2434]

The way I did it for converting from EFI to carb, I bought a 3/8" pickup with return line sending unit for a 68 Mustang. I cut it and connected a 90 degree end with a carb style sock that terminated in the same location as the large EFI sock did in the baffled location in the EFI tank.

[@frankrizzo3922]

Good information 👍 thanks!

[@sbf_fox2434]

You can also turn the factory EFI pump on constantly by grounding one of the wires in the diagnostic connector under hood.

[@frankrizzo3922]

Thanks i haven't tried that.... but don't know how long the stock pump would last if always tryn to pump out all that high fuel pressure 🤔 but forced to be regulated down to just 5psi? - well, I did run a 88' GT Fox body 302 4bbl for good couple months with factory high pressure pump almost everyday till I sold it... it lasted that long anyways.....

[@sidewyndersshed1676]

Good video thanks! On the new engine for my 92 W250 (That I will be puting in this spring) I am using a carburator, and mechanical fuel pump. The original TBI electric pump lasted 29 years. The 1st replacement pump lasted 11 months, the second one was no good straight out of the box. The 3rd has been doing good for a month so far. I am kicking around the idea of using the mechanical pump as the primary, and the electric as a backup. (Very common in aircraft, I was an aircraft mechanic,) I just have to figure out the correct plumbing. Any suggestions or thoughts would be appreciated. This is not only my daily driver, but the wife and I use it with a camper off grid in the middle of nowhere whenever possible. So having a backup system, and not having to replace either a mechanical or electric pump out in the woods would be nice. 👍🤣

[@frankrizzo3922]

Well id say use a electric pump mounted on your inner fender with power and a switch using fuel lines and ball valves to be able to re-direct fuel if mechanical pump fails in a quick easy way! Hope this helps!! 😉

[@sidewyndersshed1676]

@@frankrizzo3922 Thank you sir. That's pretty much what I was thinking, especially plumbing the fuel lines with valves to isolate each system. Although I am contemplating using the stock electric fuel pump with a fuel psi regulator, and keeping the return intact for that system, (may help alleviate any vaporlock on hot days when working the engine hard) Just a thought I'm kicking around, I've got 5 months to figure this out. 👍😁

[@5sapaches25]

What’s Holly carburetor cfm? Good info, thanks. 👍

[@frankrizzo3922]

Old school 600 ..... but its a double pumper carb... I've never even seen a 600 dp but apparently they do still make them.... list number is 4776-3

[@frankrizzo3922]

Old school carb won't idle... so it's going to need looked at... So Holley 650DP is the new carburetor I've selected... 😊