mechanical to electric fuel pump
 

I bought a high volume mechanical pump for my 355 build but learned my fuel pump rod hole was not drilled out on the block.So I plan on buying a electric pump an reg.My 85 TA was an LG4 carb car.I searched and it seems the best place to mount one is in the rear of the car.My question is how do I use my existing fuel lines that run along the fraim rail?I am not sure witch is the return line and do I use a retun line on a electric pump?? Thanks

Re: mechanical to electric fuel pump
 

IIRC, there'll be the supply line, return line, vapour line, and a vent line running from the tank, you should be able to trace them easily enough from underneath.

If your electric pump doesn't have an internal bypass spring, you'll need to use a return regulator. Otherwise you could use a deadhead regulator, but a return regulator would be preferred.

Re: mechanical to electric fuel pump
 

O.K so I will mout a pump near the tank splicing into existing lines and add a regulator on the frame rail in the engine bay.will the factory steel lines be ok for the return line from the regulator?I have read tons of posts and I am just hoping to get this right the first time.thanks

Re: mechanical to electric fuel pump
 

Or you can buy a low pressure fuel pump, and not require a regulator. Depending on what you want.
I used a summit knock off of the holley "red" I believe. It's a 5-7 psi pump, so no regulator needed. I'm pumping into my block mounted mechanical pump though, either way.
The factory lines are fine to reuse.

The largest line, 3/8", is the supply line. The 5/16" line is the return line. The smallest line, 1/4", is the vapor line.

The 4th line coming off of the tank has a vacuum relief valve attached to it with a hose, mounted on a bracket just in front of the rear axle. If you mount the pump where the factory put the EFI fuel filter (easy to find, it's a "hump" just ahead of the lower control arm mount on the driver side), you won't have to worry about the 4th line.

Another choice is to drop the tank, install an EFI pick-up with the electric pump in it, and put a return-style regulator up by the engine. That's what I'm currently doing for my LS1 swap. But, be aware the factory harness is different for a carb car vs. an EFI car.

Re: mechanical to electric fuel pump
 

Ah good, I thought the sizing was universal, but I didn't want to mention it in case I was wrong (ie, 3/8" supply, 5/16" return, etc).

Hint- Aftermarket fuel pumps (ie holley red) are LOUD. Get used to the buzz/whine. An in tank pump is quiet... Dropping the tank sucks, but buy that'd be a nice alternative...

Re: mechanical to electric fuel pump
 

I think I will put a pump in where u suggested five7kid I may try a procomp pump with an inline filter setup before the pump. These guys have always done me good on any part I bought from them I will also add a regulator in the engine bay.Is the return style reg.Just as it sounds (return line running back to the tank).Your also saying leave the vacum relief and the vapor can as is.Thanks again for the help let me know if this pump will be ok.Its going on a quick fuel 750 DP..http://cgi.ebay.com/ebaymotors/PC-13...Q5fAccessories

The EFI filter location won't work for that pump, as it has to be mounted in the vertical position. Finding a spot for it in the back of the car could be a challenge.