I'm running a mid engined B18C4 Honda Vtec engine, approx 200BHP+
370cc injectors
what size fuel pump should i use?

You'll need about 65 Litres per hour (that's 15 Gallons per hour) for 200bhp.

That's at 43 psi or 3 bar.

If you sized your pump, say 20% bigger, then I would think you'll be fine.

Obviously talk to the pump manufacturer about how much oversize you should make it.

[Edited on 29/1/08 by JAG]

Make sure you've got a goodly % excess on the pump. You really don't want to run out of pump power and therefore your nice engine suddenly running lean when you're revving the nuts off it!!!

Best bet would be a Bosch 044.
I run one of these to feed my F20C (S2000) engine.

You can pick them up new from ebay for about £120-130 much cheaper than rrp.