Fuel pump

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David Sharp
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Joined: Wed May 19, 2010 7:41 pm
Location: Norwich
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Fuel pump

Post by David Sharp »

Apologies if this has already been covered but what are the options on uprated fuel pumps? My modified 1275 Minor is pushing out 80bhp and the rolling road diagnostics proved fuel starvation at max revs..Not a serious problem but advice would be much appreciated.
bmcecosse
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Re: Fuel pump

Post by bmcecosse »

Best bet will be to use the Mini mechanical pump - which drives off the camshaft. This will solve any 'fuel vapourisation' problems (because it's low mounted) - and supplies fuel to Mini engines up to 100 bhp without problems. However - I would have though the SU electrical would be ok for 80 bhp - after all - it ran the original Cooper S ok and that was 75 bhp - I doubt it would be that marginal. Indeed, thinking about it - I ran my 'full race' 1293 S engine in my rally Mini on a standard SU pump without any problems. Ok I had two of them fitted - but only one in action at any time. You could try cleaning the filter in the pump - or remove it altogether. It may also be that your pump has quite a short stroke - maybe it can be lengthened slightly by adjusting the points. But the mechanical pump will work well - and they are not expensive.
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David Sharp
Minor Friendly
Posts: 29
Joined: Wed May 19, 2010 7:41 pm
Location: Norwich
MMOC Member: No

Re: Fuel pump

Post by David Sharp »

Thanks bmcecosse,I'll have a real good look at the su pump this weekend and see if I can sort things out.Must admit that after all the work I put into the engine I neglected to look at the pump until now! It's not been touched for 4 yrs.and an in-line pressure check this week showed 2.75psi..How does that compare to normal?
bmcecosse
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Posts: 46561
Joined: Wed Feb 16, 2005 11:24 pm
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Re: Fuel pump

Post by bmcecosse »

Slightly on the high side! How do they KNOW it's 'fuel starvation' - and not just a wrong shape needle in the carb ? Do you know what needle it is at the moment ??
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David Sharp
Minor Friendly
Posts: 29
Joined: Wed May 19, 2010 7:41 pm
Location: Norwich
MMOC Member: No

Re: Fuel pump

Post by David Sharp »

BDP - the previous BDL was fine at low and mid range but too lean at the top end.
bmcecosse
Minor Maniac
Posts: 46561
Joined: Wed Feb 16, 2005 11:24 pm
Location: ML9
MMOC Member: No

Re: Fuel pump

Post by bmcecosse »

Should be fine then!
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