Carbureted LSX forum - Fuel pump recommendation

I have been running a Carter 4601 pump and it is getting tired. Not sure if I want to use the same one. My car runs a 750 HP Holley with a regulator and 3/8 " line. Seems to work ok but I think the pump can't keep pace now with LS motor. Getting some skipping at mid track and is fine when I let up on it. What are most people using in there carbed versions? Thanks

i run a mallory 140 with #8 socketless line front to back. no issues.

The pump you have should be fine. Lots of guys run smaller.

I have a mallory 140 with a return regulator and 3/8 line in both directions. The pump is actually too big for what my LS2 needs.

i also run the mallory 140, -8 feed, deadheaded at regulator.

Thanks for the info. I like the Mallory as a replacement for the carter, but are alot more $$$$$$. Not sure at this point how to go.

I have had guys post pictures of their Mallory pumps that they set on fire because they were so pissed at them.

At one point I had a Summit brand 140 gph pump that worked just as well as the Mallory. I bought the summit pump when the Mallory got chewed up with some debris. The debris was my fault, but at the time I didn't want to pay the 85 bucks to get the Mallory rebuilt. The Summit pump cost under $80. After running a year or so with the Summit pump I finally ponied up the bucks to get the high dollar one repaired.

3/8 fuel line is a bit small for this large of a pump. With the regulator wide open I measure 3 psi back pressure through the return line.

I have heard the Carter pumps are quiet. My Mallory, at least the way I have it mounted, isn't quiet at all. The Summit pump is rotary vane and is definitely more noisy than the mallory gerotor.

Summit pump is a knockoff holley vane pump. They work but they have pretty much no suction,so you HAVE to make sure the pump is mounted lower than the tank. Gerotor pumps are a bit more forgiving and ALOT quieter (mine is near silent) its been in the car for more than 5 years and only seized a lower armature bearing once,and i got it used off a friend of mine.

I cant say anything bad about it at all.

So do you think a single nonreturn line that is 3/8" is to small? I would have to bump up to 1/2" and change the whole set-up. Don't really want to do that as I think that is to big for what I need..... opinions

3/8 is probably fine to be honest. Try it. How is fuel being picked up from the tank? Sumped stock tank? Cell? Through the stock pickup? If your trying to use the stock pickup your going to have delivery issues to the inlet side of the pump because it doesnt gravity feed at all.

For those that have the mallory 140 are you running a return line and are you using 1/2"?? Thanks

Is 1/2" rubber hose (the good stuff) an ok idea for fuel line if your on a budget?

Called mallory this AM and they recommend 1/2" 400 to 550 HP and 3/8" for 375 HP and under. They also told me I need a return regulator with the 140 pump

Well like I said I have 3/8 supply and return through russel AN fittings and get 3 PSI return line pressure. It works but would probably benefit from a slightly larger return line. I have the matching Mallory return style regulator.

My motor is rated at 440 hp and like I said, the pump is way more than the motor needs. It would probably support a fair sized nitrous set up.

Make sure you run some good filters too. The gerotor on the mallory wants a 40 micron filter before the pump. you will want another 10 micron before the carb. Don't run the gerotor without the inlet filter. the pumps are sensitive to debris. Rotary vane pumps can get by with a 100 micron prefilter.

Cant run rubber line front to back,bad idea and if you plan to go to the track they will bounce you for having any more than a foot total in the car.

Mine is deadheaded into a holley regulator.

Deadheaded as in no return line??

Exactly. No issues with it.

I would like to try that as I already have a Holley Reg. and I could run a new 1/2" line from the tank up to it.
Thanks

I run the walbro gsl392. Quiet, oem reliability, no issues.

All I used to use was Holley blue pumps, tried a pro comp and summit knock off but they were always up and down on pressure, constantly ha to make adjustments to the regulator.

Have the aeromotive street and strip now, does allot better and is return style reg.

All I used to use was Holley blue pumps, tried a pro comp and summit knock off but they were always up and down on pressure, constantly ha to make adjustments to the regulator.

Have the aeromotive street and strip now, does allot better and is return style reg.

Me too. Aeromotive Street Strip with return style Holley regulator. 3/8 steel line feed and return.

Hey Speedtiger, I though i read in your build thread you had an Edlebrock 120 pump? Thats what I went with, with a Holley regulator deadheaded and 3/8 rubber line. I am going to replace the rubber line with Steel this winter though. Ive heard that it can cause fluctuations in pressure. My car does fall flat on its face at 5500 and I hope its not cause of this pump, got some bugs to work out still.

Let me also add that the Edlebrock pump is noisy as heck, drives my wife crazy:)


Me too. Aeromotive Street Strip with return style Holley regulator. 3/8 steel line feed and return.

I have a fuel setup question. I have an 88 monte carlo , '01 5.3L engine, mostly stock less LS1 cam. I am running it carb'ed was wondering if at all possilble to use my stock fuel tank with some sort of fuel pump. I have the 3/8' inlet line with a 5/16 outlet line.
I also have a 5/16 return line....nay help/sugguestion appreciated....tks