965 fuel system max flow

[Jerz]

I have read on this forum that 965 stock pumps/ fuel lines can support up to 750hp. Can anybody confirm that, please?
Jerzy

[lucittm]

HP is a very difficult number to estimate because there are so many variables. I can see HP claims for cams, pistons, heads, but fuel pumps? Not so much.

Having said that, our fuel pumps are rated at 102 oz. of fuel per minute delivery volume at the outlet of the fuel filter. It works for me.

Mark

[Jerz]

Thanks Mark. 102oz/min is about 382lbs/hr, so assuming sfc of .65lbs/hp/hr under boost equals about 588hp.
Jerzy

[Jim2]

Hey Jerzy, have any updates on your project you care to share?

Boost pressure works against fuel pump delivery not to mention the static pressure you plan to run your injectors at. Don't test my knowledge on this.

sfc of .65 may be a little fat. Perhaps .55?

[911st]

I am not an expert on this but it seems to depend on the operating or system pressure you are running at.

The short answer is over 500+ CIS HP if done right.

Per one CIS expert I talked to our systems have a hard time maintaining System Pressure at high fuel delivery rates. This was confirmed by one gifted fellow Pelican that found his car did not respond with richer AFR's when he tried the old trick of shimming his Fuel Distributor for higher system pressure. When he upgraded one of his pumps to an 040 he did see better fueling up top.

Of course one dose not have to increase system pressure to get more fuel. The C2T Fuel Distributor can be modified and re-calibrated to deliver up to 30% more fuel. However this will not work with the stock WUR and might bring other issues with it.

On a car converted to EFI that might be operated in the 50-60psi fuel pressure range on boost, the stock fuel pumps are probably not going to be any issue unless you are building a very, very extreme monster.

[JBurer]

Tuner I respect has seen 750whp with the stock lines. Believe he was using 2 Bosch 044 pumps, though.
I'd be really surprised if the OEM pump supported 3x the OEM horsepower level.