OK, i have found out that the big bosch pump i started a thread on before puts out 800hp @.5 BSFC - 400 lbs/hr - 66g/ph - ~281lph.

Dont ask me at what pressure rating, cuz i dont know yet

But obviously that is a .5 BSFC and i want to know how i convert this rating into .6 BSFC since that is a better usable number when figuring out fuel supply for a boosted car

thanks

 

>I don't know how accurate this sites math is , but :
http://www.smokemup.com/auto_math/index.php
I got it from someone here ... I think

 

.6 (lb/hp/hr) * 800 (hp) = 480 (lb/hr)
480(lb/hr) * 1(gal)/6.1 (lb) = 78.7 (gal/hr)
78.7 (gal/hr) *3.78(L/gal) = 297 (L/hr)

Notice how the "units" cancel out to give the answer.

Gas has a specific gravity about .735 or 6.12 lb/gal.
there are about 3.78+ Liters per gallon.

I got about 248 L/hr for your .5 BSFC, by the way.

The easy way to convert from .5 BSFC to .6 BSFC would be:

.6/.5 x 248L/hr = 297L/hr.

 

Wait, so a pump actually flows more fuel @ .6 BSFC, i thought it would flow less

i'm kinda confused

 

BSFC is pounds of fuel per hp per hour. That is the engine's demand.

If the engine demands .6 lb/hp/hr, and the pump is adequate, it will fill the demand. If it's not, get a larger pump.

 

Ok, i think i understand how the BSFC works and it determines what the engine needs in terms of fuel

i think where i'm getting confused, is if this particular pump can support 800hp @ a .5 BSFC, what can it support at a rating of .6 BSFC?

What XXXhp rating does it go too?

Thats what i meant is that since the engine demands more fuel and the pump can only flow so much, wouldn't that mean that it's pump rating for horsepower would decrease?

or i am just missing something?

 

I think what you are saying is that the data sheet or some catalog listing told you the pump would support 800HP at 0.5BSFC. If this is the case, then at 0.6BSFC, it would only support:

(0.5/0.6) X 800HP = 0.83333 X 800 = 666HP

But the whole thing is meaningless without a pressure specified. This could be the flow capability at 0psi, which is meaningless in a high pressure fuel injection application.

You also need to check the rest of your math. Using 6#/GAL for fuel is OK, and that's where you got the 66G/HR (actually 66.6). But the conversion to liters is to multiply by 3.785, so that is 252L/HR.

Get the flow vs pressure data points, and we can tell you exactly what HP it will support. Remember also, you always want a little recyle in the system, so you don't want to size the pump to max the fuel pressure regulator out at max fuel demand... there will be no room for error.

The Bosch pump I use (984) is rated at 400#/HR at 0psi. It is only rated at 325#/HR at 50psi. In real world terms, that's a good 500HP pump.

 

hmm...ok i understand better

The problem is that there seems to be no pump curve for this particular pump

It took a lot of digging to just find out where it came from

Another person called a shop that sells this particular pump and they are using it on a turbo porsche that is making just shy of 800hp.

I need to give them a call and ask them a little more about the setup and if they ever made a pump curve for it

I guess the only thing i can really do is buy the pump and create my own pump curve i suppose

Measure the voltage at the pump and then just set my regulator at a couple different pressures and measure out what they flow *shrug*

 

I have a Kinsler catalog that has a bunch of Bosch pumps, rebadged as "Kinsler" pumps. They have a flow/pressure rating for 0, 20, 50, 70, 100, 120psi. The largest one they sell is rated 420#/HR at 50psi, so maybe that is the one you are looking at.

I have searched everywhere for data on the Bosch pumps, by part #, and I couldn't find any. Not sure why Bosch wouldn't make this kind of info available on their website????

 

Could possibly be...this pump as far as i know was only used in the 1979 RSR racecar

when you put 420"#"/hr, what do you mean by the "#"?

pounds right?

Would you be able to post the information you have on the pump curve for this pump?

thank you

 

TTT

just curious if you post up that pump curve for that 420# if you could

i appreciate it

 

Kinsler 10211:

Inlet: 18mm female
Outlet: 12mm female
Weight: 2.18# (yes # = pound)
Diameter: 2.36"
Length: 6.69"

PSI--Lb/Hr--Amps
0------490----7.6
20----445----8.7
50-----420---10.3
70-----390---11.9
100----350---14.6
120----315---15.8

Kinsler 10208:

Inlet: 0.475" O.D. nipple
Outlet: 12mm female
Weight: 2.31# (yes # = pound)
Diameter: 2.37"
Length: 7.00"

PSI--Lb/Hr--Amps
0------400----5.5
20----370----6.9
50-----325---8.7
70-----300---10.0
100----260---11.7
120----200---13.0

Fred