i have a BBC Chevelle with a mechanical six valve Clay Smith fuel pump that I have had on the car since the mid-90s. It's working fine and I've never had a problem with it but the thing is approaching 30 years old and I'm afraid to drive it very far in case the diaphragm finally gives up. Thinking about going to an end tank electric pump with a return regulator from Aeromotive or similar. Just wondering about reliability. I like to drive this car so I don't want to have to worry about electric fuel pumps going bad in the middle of nowhere. Factory electric pumps last a long time but so do old mechanical pumps. This is a carbureted car with a quadra jet. A mechanical pump has the advantage of simplicity but the electric pump in the tank has some advantages too. Just wondering what you guys thought I should do
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- Thread starter hooblesmelcher
- Start date
Carry a good spare mech pump, gasket and the needed tools, JMO, P.S. Should've seen all the stuff I carried in my saddle bags before I completely rebuilt my old shovelhead lol including a roll of thick tie wire 
Low-pressure electric pumps for carburetors are a PITA.
How much HP are you running ? A stock pump is fine 90%+ of the time.
How much HP are you running ? A stock pump is fine 90%+ of the time.
im talking about an in tank factory style electric pump that pushes fuel from a sump so it would be a higher pressure pump with the appropriate regulator although i guess a tbi low pressure pump could be used. main concern is reliability. the car makes around 500 hp but a 532 is going in eventually. still a daily driver deal but 700 ft lbs
I would try a stock pump but use a 1/2" line from the tank and reduce it to 3/8" right at the pump and see if that would handle it.
If not, then I would go with the Holley mechanical pump.
If an in-tank pump fails, there's no easy fix away from home.
If not, then I would go with the Holley mechanical pump.
If an in-tank pump fails, there's no easy fix away from home.
cage2592
Administrator
Id replace the Mechanical with another. Standard 454 with carb is a mechanical. Especially if the mechanical has served you well all these years.
Though most Mechanical suck these days and made with and in Chinesium.
At this need and price point:
RobbMc Performance
All day, everyday
If you are dead set on a return, get one of their regulators as you can run them with a return or deadhead.
I'm personally not a fan of Elec. Especially in tanks.
Though most Mechanical suck these days and made with and in Chinesium.
At this need and price point:
RobbMc Performance
All day, everyday
If you are dead set on a return, get one of their regulators as you can run them with a return or deadhead.
I'm personally not a fan of Elec. Especially in tanks.
Last edited:
i have a dead head regulator right now but with a higher volume and pressure pump the return style becomes more important regardless of electric or mech. the pump in it now is like 135gph and around 9psi unregulated so its marginal with the holley blue regulator as far as heating the fuel vapor lock etc although i havent had any problems
As far as electric pumps go fabricating an access panel in the trunk wouldn't be a big deal where you could change the pump if you needed to without removing the tank. The in tank pumps run cooler are baffled and are designed to run at low fuel levels without cavitating. When you let the car set a long time you don't have to crank the shit out of it to start it because the carburetor is empty you just turn the key on. I'm just thinking .everyone has made good points
That's a really nice pump.
I will try a stocker first and then go to the Robb pump if needed.
My 489 is around 525 hp.
appreciate the link. who makes his pumps i wonder. they are six valve like the one i have
cage2592
Administrator
I believe they make all their own products. I personally like the 1100hp pumps with their dual mode regulator.
We've used their Power Surge not to long ago with a Sniper FI and Belt drive pump. works great when or if you needed an elect pump of fuel to prime a system. Many different uses.
We've used their Power Surge not to long ago with a Sniper FI and Belt drive pump. works great when or if you needed an elect pump of fuel to prime a system. Many different uses.
This is what I used in my Monte. Been about 6-7 years now, not sure how many miles. No issues so far.
www.summitracing.com
www.summitracing.com
AEM Electronics 50-1200 AEM Electronics High-Flow In-Tank Electric Fuel Pumps | Summit Racing
Free Shipping - AEM Electronics High-Flow In-Tank Electric Fuel Pumps with qualifying orders of $99. Shop Fuel Pumps at Summit Racing.
Aeromotive 13301 Aeromotive Universal Bypass Regulators | Summit Racing
Free Shipping - Aeromotive Universal Bypass Regulators with qualifying orders of $99. Shop Fuel Pressure Regulators at Summit Racing.
gonna call robbmc tomorrow
if i stay mechanical im going to finish running my -8 stainless line and modify the sending unit. thinking of splitting the line and running 2 socks
You ever check out Tanks?
www.tanksinc.com
TANKS Inc. gas tanks for street rods, muscle cars, custom cars and trucks
Tanks, Inc. manufactures fuel system components and polyethylene, steel and stainless steel gas tanks for street rods and special interest vehicles.
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cage2592
Administrator
When we did my buddies Camaro with new fuel system mentioned above, we installed the below on the bottom FWD (lowest point) of his gas tank with an -8 AN fitting. Ran it straight to the belt pump. For his SNIPER FI return line, we retained and used the old stock 3/8 fuel supply line.
On my 75 Chevy, I'm doing the same and installing one on each saddle tank and running a large 'equalizer' tank line to both. Only filling through one tank and using one supply line instead of the old tank selector switch and multiple supply lines.
Deviant Tank Sump
On my 75 Chevy, I'm doing the same and installing one on each saddle tank and running a large 'equalizer' tank line to both. Only filling through one tank and using one supply line instead of the old tank selector switch and multiple supply lines.
Deviant Tank Sump
The Holley mech pump & Holley 1,000HP on my 489 came off a 71 Chevelle with a 700+ 540ci and ran great feeding it, owner decided to go EFI so sold me those parts so IMHO unless you're going with EFI, FI you really don't need an elec pump to feed 700hp, engine builder I know is building my friends 500ci 700hp Mopar engine, I think I'm going to ask his thoughts just for the heck of it
The Holley mech pump is rated 110 gph which is 3X what a normal pump can handle.
Considering you'll be down the 1/4 mile in 10 seconds, do you really think the float bowl level will go down enough to matter ?
Are you running a 950 standard type Holley or a Dominator ?
I wouldn't run a Dominator on the street.
Considering you'll be down the 1/4 mile in 10 seconds, do you really think the float bowl level will go down enough to matter ?
Are you running a 950 standard type Holley or a Dominator ?
I wouldn't run a Dominator on the street.