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petrol pump
davef - 1/8/02 at 09:24 AM

hi guys i am about to run a 1600 x flow cw twin 40 webers any ideas what rating electric fuel pump i should fit to give correct supply. cheers.


JohnFol - 1/8/02 at 11:51 AM

I was under the impression a carb has a float chamber that acts like a cystern, ie when full no more fuel can get in. Any surplus goes down a return pipe.
Could someone clarify?


johnston - 1/8/02 at 05:10 PM

the trouble is if you use too small a pump i.e. the standerd mechanical 1 it cant fill the float chamber quick enough under sustained high throttle so u effectivly run out of petrol.

although worked on a sunbeam 1.6 rally car on twin 40's and the mechanical pump was fine for that. so it should be fine for a x flow


theconrodkid - 1/8/02 at 05:30 PM

If you put a high pressure pump on you need a return pipe or the carbs will flood,maybee a pump of a carbed jag would do,injection is about 60psi thats a bit too much i think


ChrisW - 1/8/02 at 06:21 PM

I used a standard mechanical fuel pump on a 1.6 CVH on 40's without any problems. The only thing I do know (and this may not apply to the X-Flow) is that you need downdraught carbs to do it otherwise there's not enough room for the pump.

I've actually got a Facet 'silver top' electric pump now because the CVH has gone up to 2 litre. It just uses the standard line (ie no return) and makes an interesting (or annoying depending on your viewpoint) tapping noise when it's running which is quite good at persuading you to take it easy when you realise how much louder it gets when you're thrashing the car... (makes you think of all the extra petrol it's pushing in!)

Anyway, back on the subject. I got it from SCA Race and Rally (the local place for that kind of thing when I lived with my parents). See this page http://www.sca-racerally.co.uk/engine.htm. It was about £60 I think.

Cheers, Chris.


JohnFol - 1/8/02 at 06:59 PM

But surely a mechanical pump takes power away from the engine as it requires the cam to actuate it ..


ChrisW - 1/8/02 at 07:07 PM

yes, but.. you can push the petrol pump with one finger so I doubt you'd notice it, even with 20 fuel pumps!

Chris