Hi all,
I'm doing some work on an MK locost fitted with a 1200 bandit engine and there is some debate as to what sort of fuel pump to use, as the carbs are gravity fed on the bike, I have suggested the old style 'ticking' SU pump because of the low pressure, The owner of the car has tried modern car pumps but they are too high pressure, any suggestions??

Car pumps work at around 4-7psi, which will un-seat the float needles in a bike's carbs, resulting in flooding. It's virtually impossible to acurately set aftermarket fuel regulators that low.
Bike fuel pumps are set at around 1.5 psi, and are used on many models, both injected and carbed. Just get one from a breaker. They seldom go wrong.

Or otherwise put a fuel pressure regulator set to about 1.5 psi in the fuel line just before the carbs. I ran a BEC like this for years with a Facet 'fast road' pump with no probs. Trouble with using a bike pump is that they rarely have to push fuel as far as they would on a car, in fact, as stated, they are merely helping with the gravity feed.

Thanks for the info - I take it youd recommend a car pump with a regulator if the tankl is at the front of the car on the floor with the engine [bandit 1200] mid mounted.???

Yes, I reckon that would be the best way to ensure adequate fuel supply.

HTH Stu.

Hmmm, I'd disagree with that, I would go for a bike pump over a Facet type fuel pump and regulator any day. To get a low enough pressure, the regulator strangles the fuel flow and it can cause problems with fuel supply at high revs. Its a lot better to simply go for a bike pump which will pump to pressure rather than constantly pump. My 99 blade has gravity fed carbs, but the earlier blades had pump fed carbs. I have an older blade pump which pumps fuel perfectly happily to the front of the car, as do lots of others. I'd get a second hand bike pump from a scrapyard for about £20, job done, less complication, less weight and less likely to cause you a fuelling problem.

cheers
Chris

[Edited on 3/1/03 by ChrisGamlin]

Going slightly off on a tangent here but, can anybody see any reasons not to mount the fuel tank in the front of a front engined bec?
Col

Never really thought about it, if you've got enough room then I guess its a matter of ease of filling, and possibly weight distribution and/or safety? In a race car for example, I think the fuel tank isnt allowed to be in the engine bay, it has to be in a seperate compartment.

Chris

I put mine in the front to balance the weight was slighlty worried that front imapct may burst tank and cover passenger feet! but am going to put double skin on that side.

putting it in front with engine in front will mean high feul tank?? raising centre of grav??

pete

i]Originally posted by Macca
Going slightly off on a tangent here but, can anybody see any reasons not to mount the fuel tank in the front of a front engined bec?
Col

The yellow Dax Rush blade built by Gary Saunders of Dax had the petrol tank where the bellhousing of a CEC would be,the filler cap was on the centre of the scuttle, it looked neat and was supposed to be better for weight distribution? I considered it at one point myself cos the tank at the back seems quite vunerable ,but then i thought if the tanks gonna go up i'd rather it was behind me than in the middle of the car.