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Webers-need fuel pressure regulator?
MR930 - October 10th, 2020 at 04:24 PM

I've just put a pair of webers on my buggy and it's running horrible. It has the standard fuel pump so I didn't put in a fuel pressure regulator. Could this be my issue?
Both my other cars running webers have a regulator but are running electric pumps. It doesn't appear to be running rich. It's a new engine 1641, runs ok with the revs up but hard to take off. Ideas?


grumble - October 10th, 2020 at 06:23 PM

Barls runs a pressure regulator on his 2 litre with twin webers and i know that it ran like s...t with too much pressure, apparently they use a lower pressure but I can't remember the figure, I am sure that he wll let you know what he is running.


barls - October 10th, 2020 at 10:08 PM

off the top of my head its 1.5 but i could be wrong. ill have look but probably won't get there before monday as I'm working tomorrow.


Bizarre - October 11th, 2020 at 05:27 PM

2.5 - 3.0 lbs
http://www.redlineweber.com/html/application_guide/important_things_to_know.htm 


Bizarre - October 11th, 2020 at 05:31 PM

I have not seen stock pumps put out greater than 3 lbs

Are they Webers or something else.

What is your jetting?
Mixtures set properly

What is it doing wrong


MR930 - October 12th, 2020 at 04:53 AM

Yes 40mm idf webers. I'm going to put a pressure regulator on it. It doesn't seem to be overfueled but it's running like crap down low.


Bizarre - October 12th, 2020 at 07:37 AM

What sieve motor.? Cam?

I have never seen 44


hellbugged - October 13th, 2020 at 05:32 AM

Poor sync?



Blocked idle jets?

Blocked airs?


HS618 - October 13th, 2020 at 04:57 PM

Ive been using a stock VW mechanical pump with my 48 IDA Weber street beetle for over 40 years with no regulator. If the (unlikely) pressure is too great, add a few gaskets under the mechanical pump. Depending on the size of the needle and seat (most common is 2.0mm), a fuel pressure of 2.5 lbs is adequate.
Sounds more like a tuning problem rather than fuel pressure.


vassy66T1 - October 14th, 2020 at 09:05 AM

44's on a 1641 are on the larger side. Putting in a smaller venturi (choke) will improve low end response.
Every carb works well if you rev it but it is down low and on transition that is the tuning area


MR930 - October 16th, 2020 at 05:16 PM

Seems it was just linkages not adjusted right. I trusted my son had done it right.