Fuel Pump Dilemma

[The Dreamer]

I know mechanical vs electrical fuel pump debate has raged on and I have searched the forum for the correct answer, but now I know enough to be dangerous. So, I'll ask, "what would you do?"

The dilemma:

I have a 489 cu in Shelby block pumping out some serious HP and I'm afraid the Holley Red that comes with the Kirkham is not enough. I could go with a Holley Blue or Black pump, but those would require I re-plumb the fuel line to accept a regulator on the firewall. (I guess I could put the regulator over by the driver's front wheel well and save the re-plumbing, but it would look strange.)

The other option is to add a Carter mechanical. The beauty of the mechanical is it adds fuel as rpms go up, which is what I need. The Holley Red flow rate drops way off after 4psi (look at the Holley site. I'm sure some others running this pump will get nervous when you see the flow specs for it). The Carter flows 120 gph, so why would I need to keep the electrical pump if I went this route? Is there any benefit to having both, other than reliability?

The mechanical route is much cheaper so it seems like a no-brainer, but there are so many electrical pumps out there (including the fact the Kirkhams put them on their cars) that I feel like I'm missing something. What would you do?

[Ron61]

Dreamer,

I have used the Holly Blue pumpfor years with no problem except immediately after I put it in. I seemed to run out of gas as I opened the throttle and called the Holly Tech. First questions, was did you put a filter between the pump and tank. I told him I used the one thet sent and he told me to take it out and throw it away and not put one is as the blue pump has a filter screen on the intake side that will catch anything the filter will. So I tried this and had to really adjust my regulator as I was now putting 14 pounds of pressure to the carb instead of the 6 that it had with that filter. I now have an inline filter before the carb, and my regulator I mounted on the front of my block, but I had an extra bolt hole and made a bracket and it works out great. It is near the carb, easy to see and adjust if I have to. The Blue pump has a free flow capcity of 110 GPH. I have been looking at the Holly Pro Series Pump and may get one later on to try out. But I have ran the Blue pump since 1996 with no problems.

Ron

[ENTDOC]

Stick with the one on it.It seems to work well and there are plenty of big motors that work fine and are not starved for fuel using this system.My only gripe is that the pump is loud. chuck

[Back in Black]

14 lbs is way too much and should result in a rich condition. I had to use the Holley regulator on mine due to extreme rich condition it was creating. My "turnkey" was delivered with the blue pump and no regulator and I was left to deduce the dire need for one on my own. The Holley tech told me that 6 to 7 lbs was plenty for my 514.

[The Dreamer]

Thank for the replys. I know the Blue pump will most likely work, but I think I'm just going to add a Carter mechanical. Its $60 vs $200+ for pump and regulator not including having to re-plumb. It's the simpliest, cleanest looking and cheapest approach. BTW,

Chuck, I have too much into this engine to let it go lean on me. I need to protect my investment and 120 gph should be enough for street driving and occasional open track. I talked to Keith Craft about the Red pump and he felt it is marginal at best and be careful it you ever jump on it. If you are running a stroked 427 with the Red pump, I urge you again to look at the flow curve for this pump on the Holley site. If you are running about 3-4 psi, you will be ok, but if you are running 6 psi (which I think is about norm), you only get about 20 gph (not a typo).

BiB, the Blue pump comes with a requlator from Holley. If you paid for a Blue pump and the builder didn't install it, he owes you a regulator.