swapping out to a mech pump

**cuzncarl** · 10-22-2012, 04:08 PM

im planning on changing out my 15 year old factory gm electric fuel pump to a mechanical fuel pump. it is finally taking a crap on me. i have a bbc 454 +.30 over, mild cam, 9.5/1 compression gm hi perf iron large oval port heads with a "stage one" port n polish (according to Santa Ana Speed Shop,, edelbrock performer intake, 750 ( now about a 780)holley DP carb by CJ engineering, and soon adding some lightnings on her. my question is which size mech fuel pump should i be running and which is reliable? then how should i plumb it? i have a fuel filter/water separator sys. that came stock that i want to keep in the loop and i just acquired a aeromotive 40 micron fuel fiter and marine regulator. do i put the 40 micron in front of the fuel pump then to the separator then to the carb?
Thanks

**jordy** · 10-22-2012, 04:17 PM

I went with the Clay Smith Cams mechanical pump on mine with an Aeromotive regulator plumbed in between it and the carb (which is a 1050 Dominator, and I've never had supply issues). I draw out of the tanks and through the fuel filter/water separator.

Looks like the website is down, but George was the guy to talk to when I set mine up years ago.

http://www.claysmithcams.com/

**Mitch** · 10-23-2012, 08:48 PM

Good advice Jordy .

**obnoxious001** · 10-23-2012, 09:32 PM

If you had not already purchased the regulator, I would have probably used a low pressure(7-9 lb) pump that required no regulator,, just to keep it simple for your mild engine. I ran a 632 cu in tunnel ram engine on the dyno with one, plenty of fuel pressure even above 6000 RPM.

**Mitch** · 10-23-2012, 10:09 PM

Originally Posted by obnoxious001

If you had not already purchased the regulator, I would have probably used a low pressure(7-9 lb) pump that required no regulator,, just to keep it simple for your mild engine. I ran a 632 cu in tunnel ram engine on the dyno with one, plenty of fuel pressure even above 6000 RPM.

Key word probably..

**obnoxious001** · 10-23-2012, 11:05 PM

Originally Posted by Mitch

Key word probably..

That was my way of being kind. With a single 750 carb,, even wide open throttle he probably won't be burning 30 gallons per hour? Dyno sheet from a dual carb, tunnel ram 496 I recently ran showed 225 lbs of fuel at 5900 RPM,, 589 HP. That one had a Holley low pressure mechanical pump.

Don't get me wrong,, George at Clay Smith has a great pump,, just don't think it's necessary for his particular application.

**GoFastRacer** · 10-24-2012, 06:36 AM

Clay Smith is about the best mechanical out there ran one for years no problems and still have it, friend of mine ran one with a pair of Dominators with no problems...

**jordy** · 10-24-2012, 07:17 AM

Originally Posted by GoFastRacer

Clay Smith is about the best mechanical out there ran one for years no problems and still have it, friend of mine ran one with a pair of Dominators with no problems...

That's what I was saying Art! I have just never been a fan of Holley fuel pumps, be it electric or mechanical. Besides, when he decides that he want to go bigger down the road, he is already set in the fuel delivery department.

You missing Mesa-co yet? Ha ha!

**Mitch** · 10-24-2012, 07:28 AM

Originally Posted by GoFastRacer

Clay Smith is about the best mechanical out there ran one for years no problems and still have it, friend of mine ran one with a pair of Dominators with no problems...

I run a Clay Smith also and it has been good to me . I ran the edelbrock/style low pressure pumps on my hot rods and had to change them out it appears they do not like fuel with alcohol in it,the alcohol ate them up .Clay Smith does not make a low pressure deal,if they did I would run them on my hot rods best mechanical pump out there .

**GoFastRacer** · 10-24-2012, 08:22 AM

Originally Posted by jordy

That's what I was saying Art! I have just never been a fan of Holley fuel pumps, be it electric or mechanical. Besides, when he decides that he want to go bigger down the road, he is already set in the fuel delivery department.

I hear ya, I've had decent luck with the street pumps but the electrics forget it, they're good for draining tanks though, LOL...

You missing Mesa-co yet? Ha ha!

HA, that'll never happen, LOL....