best mechanical pump for high hp small block

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345man2

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:Dwondering who makes the best mrchanical fuel pump for a high horse small block and one that has the biggest fittings on it
 
well I really can't say who makes the best one....but I have an old Direction Connection mechanical pump ( hi-po carter ) that I bought back in 1979 for my small block, and I'm still using it. ( I'v replaced the diaphram kit a few times) and it has 3/8 ports. It's always worked great.
 
my 318 runs higher twelves in its hayday it uses a carter fuel pump not sure number but its a great pump it replaced the old carter the po put on it. it looks like the carter muscle car mech pump they called it on egay
 
looking and hoping for around 600 give or take a little:blob:
 
Carter 6270 'strip' pump. 120 GPH, puts out plenty of pressure, you need a regulator with it. I run that pump on my car - W2 340.

There's also Race Pumps mechanical pumps. They're billet ($$$) but supposedly they are 'the last pump you will ever buy' or some such nonsense.

See here.
 
Eddy performer rpm pump-6psi-110 gph-3/8" inlet-3/8" outlet. Make sure you run a complete 3/8" system from tank to carb and you should be good to go.
 
I currently have a Carter as well. I believe its a 120gph. I think I have a 110GPH Edlebrock in the garage if your intrested. Was on the car for like 5 min. I bought it to replace the Carter that I thought was bad, only to replaced it with the edlebrock and find it was a 6" section of rubber hose near the tank that was collapsing. So I fixed that and the Carter went back on because of the higer flow rating.

I would have to check the garage to make sure I still had it and figure out what I wanted for it. It would certainly save you some money over a brand new one.
 
Recently I needed a good high perf. pump and looked at all the specs on every pump I could find and noticed the Edelbrock pump is the only one to use 3/8" fittings (short of a high dollar race pump) so I ordered it. Checked it out when it arrived and upon close inspection I see that even though it uses 3/8" fittings if you look inside where the fittings screw in the i.d. in the pump body is restricted to 1/4" just like all the other pumps. IMO you gain very little with the 3/8" fittings it's drilled and tapped for. The only advantage I see is you don't have to use a 1/4" pipe to -6 adapter to install -6 fuel fittings. The 1/4" i.d. pump body inlet also explains the GPH rating not being higher than the Carter pumps. It seems to work fine, just thought I was getting something better by spending $50 more. Now I don't think so. The Carter M6270 340SFastback uses seems to be as good from what I see and it's $50 cheaper.
 
Carter 6270 'strip' pump. 120 GPH, puts out plenty of pressure, you need a regulator with it.

Agree. The pressure on the Carter 6270 will get high enough (6.9 to 8.1 psi) to require a regulator. I was running a Carter 6270 (opened up to 3/8") on my 408 equipped with a Pro Systems Pro Series 4150 Holley. I bought the pump from FBO and Don assured me it did not need a regulator. The pump was always on the ragged edge of overfilling the fuel bowls and causing the carb to run rich and occassionally flood. I did not want to run a regulator so I switched to the Edelbrock Performer RPM Street Fuel Pump 1720.
 
... the Carter 6270 will get high enough (6.9 to 8.1 psi) to require a regulator....The pump was always on the ragged edge of overfilling the fuel bowls and causing the carb to run rich and occassionally flood.

Exactly. The M6270 cuts off at too high of a pressure for most uses (w/o a regulator). Had the same issues myself. The M6902 is a generally a better choice.

On an LA with '69 and earlier water pump & timing cover, a 6 valve pump such as the P4529368 is one of the best choices.
With the Aluminum water pump, choices are more limited. I've had good success with the Holley 110 gph for small blocks, p/n 12-360-11.

Before landing on that choice, I sent three pumps to Ryan Brown (North of the border) who has a test rig for pressure and flow. If you have any questions or are circle track racing, you'll get a solid answer.
Flow, pressure and fit details on this older page on fuel delivery on my website.
 
These pumps look pretty nice. Doesn't look like they have any mopar pumps listed, but based on some of the pump pictures. It looks like they start with a factory style pump and just modify it with their own inlet and parts.

Might be worth a call over to them if your serious about a nice mechanical pump.

http://www.robbmcperformance.com/products.html
 
These pumps look pretty nice. Doesn't look like they have any mopar pumps listed, but based on some of the pump pictures. It looks like they start with a factory style pump and just modify it with their own inlet and parts.

Might be worth a call over to them if your serious about a nice mechanical pump.

http://www.robbmcperformance.com/products.html


I have a RobbMc fuell sender on my car. It's got a 1/2" pickup tube, -8 outlet fittings and a provision for a return which I don't use. I don't believe they make a pump for SBM otherwise I would have bought one.

My system is a -6 so I stepped down right after the sender but it does not seem to cause any issues. I asked them directly about that, they said it was OK to do but just to do it right at the sender instead of somewhere else.

The main stumbling block using an off-the-shelf mechanical pump with higher output engines would be the line size since most are for 3/8 or less. If you can get away with a 3/8" line then it's fine but step up to a 1/2" and you're going to have to step down to the pump inlet which is probably not good. The Race Pump I referenced above has -8 inlet and outlet so in that regard it would be a better choice.

The Carter inlet and outlet sizes are NPT so you just use an adapter if you're using -AN fittings.

Also on the Carter pressures - before I put the regulator in line, it was 12 psi. Not kidding!
 
wonder if you could tap the inlets for a bigger size , I have one of the older carters:blob:
 
wonder if you could tap the inlets for a bigger size , I have one of the older carters:blob:
Wouldn't help if the passages behind them are only 1/4 ".
You could possibly take it apart , re-do the innards and do a diaphragm kit while you are at it........but by now , a new pump would make more sense.
Personally , I think a mechanical is marginal for 600 h.p. unless you use a pusher too.
Might work , but I'd rather go with a nice electric.
 
Demon408 - Thanks. One day I'd like to reduce the text and add more pictures but I never get around to it.

There are some clever solutions to shutting down electric pumps during accident situations for those who go that route. But my preference was mechanical as I wrote there.

I should have mentioned Ryan Brown was very reasonable. A bit of a delay in shipping across the border - even back then.

tubtar - There's no passages inside. Volume capacity is determined by the little flapper valves. If a npt to hose nip is being used, it may be worth using one that has a smooth transition and ease the sharp edges on the ID. A lot of times I've seen the worst transitions on dual feed hard tube to the carb. The inside where it splits from single 3/8 tubing can often be improved.

It would be great if someone like RobMc packaged a higher capacity pump (more valves) in a smaller body so it would work with the 70 up water pumps. Maybe 4 or 5 valves instead of 6. It would still be better than the typical 2 or 3. The other solution would be a pre-70 water pump in aluminum. Then we all could use the 6 valve fuel pumps with no issue (other than a bunch of us would be moving our radiator outlets to the other side.) :)
 
has anyone used the race pumps they look pretty cool :D
 
Demon408 - Thanks. One day I'd like to reduce the text and add more pictures but I never get around to it.

There are some clever solutions to shutting down electric pumps during accident situations for those who go that route. But my preference was mechanical as I wrote there.

I should have mentioned Ryan Brown was very reasonable. A bit of a delay in shipping across the border - even back then.

tubtar - There's no passages inside. Volume capacity is determined by the little flapper valves. If a npt to hose nip is being used, it may be worth using one that has a smooth transition and ease the sharp edges on the ID. A lot of times I've seen the worst transitions on dual feed hard tube to the carb. The inside where it splits from single 3/8 tubing can often be improved.

It would be great if someone like RobMc packaged a higher capacity pump (more valves) in a smaller body so it would work with the 70 up water pumps. Maybe 4 or 5 valves instead of 6. It would still be better than the typical 2 or 3. The other solution would be a pre-70 water pump in aluminum. Then we all could use the 6 valve fuel pumps with no issue (other than a bunch of us would be moving our radiator outlets to the other side.) :)

The Edelbrock pump claims to be a 6 valve pump and is a std. size body. But as I mentioned earlier the i.d. of the inlet in the body is only 1/4". Haven't taken one apart to see if it could be improved.
 
I run this one with 3/8 line and 3/8 pickup works great:

http://www.summitracing.com/parts/crt-m6270/overview/make/plymouth

Yes, I use that same pump on my hot street 318. I noticed the pressure was way up there, 11-12 PSI, at idle! So after a while I had to install a regulator...I used the cheap Holley 12-803 deadhead regulator.

here's proof!

IMG_0476-1_zpsb706d857.jpg


then just plumbed the regulator, runs at a constant 6psi.

IMG_0480_zpsd8b26252.jpg


IMG_0482_zps316db812.jpg
 
has anyone used the race pumps they look pretty cool :D

Again, I think it would be the best choice for your application because of the port sizes. It's basically exactly what you're looking for. IMO, the Carter, Holley or Edelbrock would be marginal since the general application for those pumps is usually for a hot street machine, like around 400-450 hp. Once you're past that, you probably want to start thinking about a -8 delivery system and possibly a return so you're beyond the intended usage of a street-style mechanical pump.
 
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