Schurkey

Anyone have a RELIABLE source for fuel pump capacity?

I'm finding it very difficult to locate trustworthy specs for the various part numbers of in-tank OEM-style fuel pumps.

My suspicion is that most any of the Delco / Delphi / Airtex / Carter fuel pumps have about the same capacity in terms of gallons per hour. The only functional difference is the output pressure capability.

Folks advise using the Delco EP241 "TPI" fuel pump on TBI applications; the 241 will certainly push higher pressure than a TBI pump...but I bet the gallons per hour is nearly the same as the TBI pump.

I understand that the actual pump section of the fuel pump assembly can be different among the various brands and part numbers, but I think this has more to do with manufacturer choice along with pressure requirements and less to do with output volume.

The specs I'm finding is that typical volume for a non-Walbro pump is about 20--25 gallons per hour.

HAS ANYONE TESTED THE DELIVERY VOLUME OF THE TBI PUMP versus THE 241 (or equivalent) TPI PUMP?

UnderCover89TBI

iTrader: (25)

Pump delivers volume not pressure. Stock tbi pump could not deliver enough fuel volume to run at 15 psi on my engine, whereas the tpi pump could at that pressure and higher pressure.

Ronny

iTrader: (1)

I did a search a year ago due to my N20 install with 350 HP on the motor w/o N20 "on". I "read" somewhere on a vendor site GM Delco TPI pump delivers 24 gal/hour or 91 liters/hour. to convert to lbs of fuel gas weighs 6.15 lbs / gal

Schurkey

Not exactly true. The pump used in the TBI fuel pump assembly cannot generate higher pressure. Not a matter of a shortage of volume, it's a matter of pump design. You could trigger the pump with the engine OFF, and not get ~15 psi. Wouldn't surprise me to discover that the electric motor was weaker than the one used in the higher-pressure pumps.

The TPI fuel pump assembly uses a different kind of pump within the fuel pump assembly that is suitable for higher pressure.

Yeah, that's about what I found; but it would be nice to have a spec for the TBI pump as well as some of the other part numbers.

24 gph isn't much. It'd struggle to support 300 horsepower (if that!)

Ronny

iTrader: (1)

104 #/hr supports 393 HP per RBobs calculator.
I believe he uses 80%DC for calc. Not sure on BSFC? Maybe .45
104 lbs /6.15 lbs = 16.9 gallons/hour of fuel needed at WOT.

granted I "read" 24 gal on a vendor site.

UnderCover89TBI

iTrader: (25)

good info. guys. Shurkey corrected me. Thank you.

thomas1976

I belive that 24 GPH is wrong for the AcDelco #EP241.

Ronny

iTrader: (1)

Then 40 gallons it is !

Schurkey

I don't know RBob or his calculator. Figures seem WAY off to me.

(Round figures) Assuming .5 lbs. of fuel per horsepower per hour delivered at the appropriate pressure:Even with your figures of 0.45 bsfc and 6.15 pounds per gallon, I come up with 22 gallons per hour.

22--25 gph at 6 psi takes much less pump than 22--25 gph at 40 psi.

If a TPI pump supports more than about 320 REAL (not "butt dyno") horsepower, I'd be amazed.

Schurkey

Got a link to the 40 gph? Does the 241 really throw 65--70 psi maximum?

Ronny

iTrader: (1)

My error.

The 104# was the output of each injector(2). 75 lbs injector size at 25 lbs FP puts out 104# of fuel per hour, Each injector firing at every other distributor reference pulse(TBI) supports 393 HP. So 208# of fuel is delivered in an hour from injectors.

400HP/.5 = 200 lbs fuel...... 200 lbs/6= 33 gal

TPI pump puts out 40 gal/hr. I found 3 references to TPI pump output today.

Is this now accurrate?

Schurkey

Excellent!

Can you provide links to your sources?

Ronny

iTrader: (1)

One was an LSx Forum one was Thomas above and the third another forum I forget. Nothing credible just opinion.

thomas1976

You need to search in the AcDelco parts distributor catalog.
65-70 psi shutoff means, the pressure at wich no more flow occours.

I had the gauge showing somewhere around 60 psi once, by setting the fuel pressure.

one92rs

iTrader: (5)

wow this is really good info. we need a fuel pump sticky and all this type info in it.

Schurkey

May I also suggest:
https://www.thirdgen.org/forums/tbi/...ml#post4905005

Ronny

iTrader: (1)

I checked the AC Delco site and did not find specifics on output of the 241. I did countless searches and only found references to 40 gal but also to lesser flow#'s mentioned. Other aftermarket mfg's post #'s but I see nothing specific to ep241.

Ronny

iTrader: (1)

Back from dead.... I am about to put it to test.

I have a forged 396 SB Chev block in car today.
But not yet running. Will fire it up in a couple weeks if we can get interior done. Then goes to muffler shop. Compression 11.0/1. Cam 234/242 .05 112 LSA. 1.75 Hooker headers 3.0 dual exhaust. Edel Vic SP. Ported Edel RPM heads(2007). Port fuel/1000cfm Edel 4 barrel TB with EBL/ECU. Weak link is 24 lb injectors which will be replaced. TPI pump.