Fuel Pump Flow Ratings
Chris Fasulo
Pump Numbers and Flows
Below is a table of various fuel pumps and their rated capacity compiled by a friend of mine, Todd Ellis. He is not a list member but owns an '87 GN and an '87 T-Type. Todd is a mechanic by trade. He obtained this info from a 1994 Carter Fuel Pump book and by contacting Walbro directly.

Pump Description Carter PN Gal/Hr PSI Shutoff
Stock '87 GN/TR Pump P74008 28 50
1994 LT1 Corvette P74132 33 50
'89 Turbo Trans Am P74074 38 50
'91 GMC Syclone P74074 38 50
'92-93 Ford Supercoupe P74645S 42 91
Walbro 526 P74105HP 44 93
Walbro GSS 242 None??? 55 100

All flows are free flowing @ 12v DC

Lately there have been some questions posted to the list on what to buy for a fuel pump so I though this table would be helpful. The Walbro GSS 242 pump is available from ATR for $99 under part # GM507-242A. They also have a fuel sock and wiring connector available for this pump for under $10. This pump is flow rated at 44 GPH @ 70psi @ 13.5volts!!! If you can find a better in-tank pump, BUY IT, then let us know what it is!!! I've seen no better pump than this one. While *I CAN NOT SAY FOR SURE*, I believe Modern Muscle's "Muscle Pump" is the Walbro GSS 242. (They are claiming the same 44 GPH @ 70psi in their catalog) I bought my pump form ATR so I do know for sure they are selling this pump under the above part #. Both ATR & M.M. are good reputable companies to buy from so take your pick!

Modified stock pumps, puller pumps, and fuel enhancers are pretty much things of the past. (I'm not saying these items do not work nor am I suggesting that their use be discontinued) One good in-tank pump properly hot wired will take you to the bottom of the 12s and into the high 11's safely. For about $120 the GSS 242 is a great pump and very cheap insurance!

I have the Flow vs Pressure performance graphs for the Walbro GSS 242 and the 525 pumps. If anybody wants copies of them I can FAX them to you. Reply directly to me--NOT THE LIST--with your FAX #.

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