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twin 40s
will642 - 3/1/23 at 08:15 PM

is a standard pinto fuel pump recently replaced ok for fueling twin 40 dellortos? will i need a pressure regulator ?hopefully someone can advise.

Mike Wood - 3/1/23 at 11:09 PM

quote:
Originally posted by will642
is a standard pinto fuel pump recently replaced ok for fueling twin 40 dellortos? will i need a pressure regulator ?hopefully someone can advise.


Gut feeling is that you will need an aftermarket electric fuel pump, e.g. a Facet, and a fuel regulator such as a Malpassi Filter King. the state of tune of your engine would determine which flow rate of Facet you will need. Hopefully someone more informed with experience of tuning Pintos will reply. Or you could try asking Burton for advice.

If you do not need an electric pump for twin 40s then maybe the carbs are too big for the state of tune of the engine!

Cheers
Mike

cliftyhanger - 4/1/23 at 08:08 AM

I would suggest the std pump will be OK. The pump will be sized to easily cope with a std engine, and twin 40s are unlikely to use more than twice as much fuel at peak demand than whatever was originally fitted. And remember, fuel pressure is pretty irrelevent with carbs, it is all about flow.
Not sure if there is data available for mechanical pump flow rates? But remember that a mechanical pump increases flow with revs, I doubt it is proportional.
Not sure how it could be tested. Maybe a low pressure gauge and rev the engine, see if the pressure drops to zero?

If you do go electric, buy a proper brand. Some of the copy pumps are "variable" in quality and longevity. Huco do some nice low pressure pumps, so no regulator required. They also do push or pull versions, so can be in the engine bay as opposed to facet etc which need to be near the fuel tank and are push only.

Edit, a search (Teabreak) suggests the mecghanical pumps are ok to around 140bhp, some say more, some less. So it depends on what the engine is expected to make. And if you intend having max power for more than a few seconds at a time.

[Edited on 4/1/23 by cliftyhanger]

JoelP - 4/1/23 at 01:17 PM

I find my pinto on twin carbs feels under fuelled at full throttle and revs. May as well ensure you're off to a good start with a suitable pump. I seem to recall that motorbike pumps work fine for cars. (carb bikes obviously...)

Dingz - 4/1/23 at 05:34 PM

Standard mechanical pump will be fine, if the float needles are a bit worn you may want to fit a regulator and set it around 2psi.

will642 - 4/1/23 at 08:24 PM

thanks for advice ill try it first on standard pump with a possiblr view to going electric if i find it underfueling.

SJ - 5/1/23 at 04:59 PM

quote:
Originally posted by JoelP
I find my pinto on twin carbs feels under fuelled at full throttle and revs. May as well ensure you're off to a good start with a suitable pump. I seem to recall that motorbike pumps work fine for cars. (carb bikes obviously...)


I've got a bike pump on my MGB on SUs which (so far) seems OK. Not fully tested yet though, but not expecting any problems given how well the same pump works on my Zetec on Mikunis

Oddified - 5/1/23 at 09:16 PM

Many years ago i ran a tuned pinto on 40's with the standard mechanical fuel pump (no regulator), never had an issue.

Ian