Is an SR head the same as a L head?

[beavy69]

so I could just stick that bp 285 that you got in my cam housing and run it on the sri head?

[mikey14sr]

yep

[Adam]

what controls how much fuel it shoves in? (an air flow meter?)

Thats what a carb does, puts fuel into the air flow.

You could use an electric fuel pump with a pressure regulator to get it down to carb pressure.

[beavy69]

Yeah but carbs have their own resovior of fuel that is topped up by the fuel pump. In normal small engine novas like mine there is a mechanical pump powered, and thus flow rate mediated, by the speed of the engine. But with more fuel going in with bigger carbs I don't think a standard mechanical pump will supply enough will it?

In which case, as an electric pump is not driven and thus controlled by the engine, what determines how much fuel it needs to pump?

[mikey14sr]

I think it's the speed of the pump motor or a limiting valve built in to it, for example, a facet red top is regulated to 6-8psi, at a flow rate of 45us gallons per hour.

[Adam]

Yeah but carbs have their own resovior of fuel that is topped up by the fuel pump. In normal small engine novas like mine there is a mechanical pump powered, and thus flow rate mediated, by the speed of the engine. But with more fuel going in with bigger carbs I don't think a standard mechanical pump will supply enough will it?

In which case, as an electric pump is not driven and thus controlled by the engine, what determines how much fuel it needs to pump?

Ye, the electric pump supplies a constant amount, and the regulator then alters the amount to the engine as required.

A standard nova mechanical pump can run twin carbs fine afaik, using a pressure regulator.

[beavy69]

does anyone know how much I need to get the 1.4SRi head skimmed by if i'm putting it on a 1.3 block?

[beavy69]

So does the regulator just go on the hose between the pump and the carbs?

do they need a power sorce or are they simply a valve?

cheers

[Snowface]

the standard mechanical fuel pump found on Pierburg equipped Nova's is more than adequate for the job. in fact its too adequate at 6-8psi.

If your running Weber or Dellort then you need precisley 3.5 and 3psi respectivley. Much more than this and you will be flooding the float chambers and start washing the bore's (which ain't good).

Mpi and Spi pumps are waay to powerful. if your going for an electric pump then make sure its low pressure and is regulated to the amount stated above.

The mechanical pump in tandem with a regulator (e.g. fuel king) is absolutley fine though.

[beavy69]

Does it matter is I use an SRi head from a spi or mpi?

and if I used the SRi inlet manifold to fit carbs could I just plug the injector holes?