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bbrock
What's a good bypass regulator for dual carbs? Thinking I might just stick with the stock fuel pump if it still works since I already have it and will be running a return line. Otherwise, I'll get a Carter. Seems there are a lot of crappy regulators out there so I'd like to make sure I get something reliable.

Thanks.
sithot
QUOTE(bbrock @ Jan 10 2019, 09:08 PM) *

What's a good bypass regulator for dual carbs? Thinking I might just stick with the stock fuel pump if it still works since I already have it and will be running a return line. Otherwise, I'll get a Carter. Seems there are a lot of crappy regulators out there so I'd like to make sure I get something reliable.

Thanks.


Aeromotive
johnhora
PMO

https://www.pmocarb.com/parts.htm
MarkV
Running a high pressure pump and a regulator seems like added complication with extra lines that could leak or cause a fire.

Someone here recommended this one to me:

https://www.cbperformance.com/product-p/3193.htm

It is internally regulates and installs in the stock location. I have had it for years... its quiet, reliable and not very expensive.



yeahmag
I second the CB pump.
sithot
QUOTE(yeahmag @ Jan 11 2019, 12:56 AM) *

I second the CB pump.



I agree there are bad regulators but Aeromotive isn't one of those.


A low pressure pump is ideal. I removed my PMO setup after acquiring an NOS Bosch pump as used on the early LWB carbureted 911’s and 914-6. Pressure is perfect and it uses an internal return to the tank.

Stoddard sells these but they are not cheap. Carter, Holley, Pierburg and others are decent choices. You do get what you pay for in this market.

When I went from PMO's to Webers there was a lot of back and forth with Paul Abbott at Performance Oriented who I consider to be the preeminent Weber expert. We discussed regulators, pumps, AFR meters and other minutia. In the end the Bosch pump went in exactly where the CIS pump came out and since the plumbing was already there (I had previously upgraded it) the swap was easy.


Click to view attachment
Mark Henry
QUOTE(MarkV @ Jan 10 2019, 10:46 PM) *

Running a high pressure pump and a regulator seems like added complication with extra lines that could leak or cause a fire.



I guess every FI car in the world needs to be scrapped because they're all ticking time bombs. rolleyes.gif

jd74914
QUOTE(sithot @ Jan 11 2019, 06:40 AM) *

QUOTE(yeahmag @ Jan 11 2019, 12:56 AM) *

I second the CB pump.


I agree there are bad regulators but Aeromotive isn't one of those.


agree.gif agree.gif

This is a certainly a case of you get what you pay for-Aeromotive makes a quality product.
bbrock
Thanks for all the feedback so far. Anyone know anything about Malpassi regulators? They keep popping up in searces for Weber carb regulators. Looks like they are Eye-Tal-Yun to match my carbs and more found in Europe than over on this side of the big water. Still not cheap, but less than the comparable Aeromotive model. They have a bonus of coming with 8mm fittings. Curious if anyone has experience with them.

IPB Image
http://www.officinamalpassi.it/en/carburet...044-detail.html
Mark Henry
QUOTE(bbrock @ Jan 11 2019, 11:33 AM) *

Anyone know anything about Malpassi regulators?


I didn't care for them, couldn't get down to 3.5lbs with a carter LP pump, but I didn't try the bypass version.
MarkV
QUOTE(Mark Henry @ Jan 11 2019, 06:36 AM) *

QUOTE(MarkV @ Jan 10 2019, 10:46 PM) *

Running a high pressure pump and a regulator seems like added complication with extra lines that could leak or cause a fire.



I guess every FI car in the world needs to be scrapped because they're all ticking time bombs. rolleyes.gif


Fuel injected cars require high pressure, carbed cars obviously do not. Just seems like a recipe for a problem to try to make a 20+ psi pump put out 3.5 psi. Doesn't take much pressure to overcome the needle and seat in a carburetor.... that and you can buy a carb pump for less than $100. confused24.gif
bbrock
QUOTE(MarkV @ Jan 11 2019, 12:24 PM) *

QUOTE(Mark Henry @ Jan 11 2019, 06:36 AM) *

QUOTE(MarkV @ Jan 10 2019, 10:46 PM) *

Running a high pressure pump and a regulator seems like added complication with extra lines that could leak or cause a fire.



I guess every FI car in the world needs to be scrapped because they're all ticking time bombs. rolleyes.gif


Fuel injected cars require high pressure, carbed cars obviously do not. Just seems like a recipe for a problem to try to make a 20+ psi pump put out 3.5 psi. Doesn't take much pressure to overcome the needle and seat in a carburetor.... that and you can buy a carb pump for less than $100. confused24.gif


When used in a bypass system set to 3 psi with return line, there is never any high pressure in the line regardless of the pump used. An EFI pump simply moves more fluid where a little is bleed off to make 3 psi for the carbs and the rest is returned to the fuel tank.

There are a few other threads discussing pros and cons of recirculating vs. deadhead systems for carbs. After reading the great info here and elsewhere, I've decided a recirculating system is the way I want to go. Once that decision was made, retaining my stock pump becomes a viable option, but regardless of the pump I choose, I'll need a bypass style regulator. beerchug.gif
bbrock
QUOTE(larryM @ Jan 12 2019, 02:01 PM) *


Unfortunately it looks like Holly's bypass style regulators are designed for a target pressure of 7 psi. The lowest pressure any of them can do is 4 psi. Otherwise, I think they'd be a great option.
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