CDFP Flow Rate
 

Well, some very important points where brought up last night regarding the upgraded cdfp. The upgraded cdfp will cure the pressure woes by increasing pressure, but with a set volume, wouldn't increasing the fuel pressure actually decrease the volume?

Sneaky just bought a CPE CDFP and they told him the upgraded CDFP flows 1520 cc/min at 1800 psi. Does anybody know what the stock CDFP flows.

I hope you will chime in Ztuner, you have had me scratching my head from the conversation last night.

not quite sure what your getting at besides wondering the stock rate

ztuner used the example of a garden hose. You have a set rate of flow. If you block off half of the nozzle, the pressure increases, but flow decreases.

The hose is the same size, just adding more flow rate and in turn is adding more pressure thru the hose. This is my understanding of the internal kit.

i thought the internals allowed more flow and pressure pretty much.

what ztuner is saying sounds right though, because even when my pressure would plummet with stock pump.... AFR was constant. Pressure went down so enough fuel could flow to maintain AFR. But as we've seen so many times with the upgraded pumps, all fueling issues have been basically solved, so its only logical to assume that the upgraded pumps have higher psi and volume.

I would like some flow numbers too... a lot of guys talk about what their psi is, but really what i would want is a pump that can flow a lot and maintain at least stock 1600psi or whatever

IF the pump is designed properly, the increase in pressure you are seeing is not due to a more restrictive path, but rather because the fuel flow volume increases.

That being said 1520 cc/min is not a lot of flow if that number is correct. 1520/4 = 380cc/min available for each injector. That shouldn't even support 300whp.

That is just hearsay. I'm waiting for a response from one of the vendors. Maybe i shall email pg or cpe to see if they have flow numbers

There is a 42% more volume of fuel pressurized per stroke (compared to stock) with the CP-E pump. Per stroke, 42% more fuel is pressurized, because of the increased diameter in open area for fuel to occupy. Therefore, pressure is kept up because the volume of fuel sprayed by injectors under full load at any given point, has just as much if not more (when pressure INCREASES) fuel right behind it being fed into the rail.

PG is 50% over stock.

Its like going from a 1/2" pipe to a 3/4" pipe, with the same pressure levels being generated

This is correct. I don't know where that flow number came from, but it isn't close to correct and if it was we would need to know the rpm for it to have any meaning at all.

I thought when the pressure dropped, the ecu closed the throttle to maintain the targeted AFR?

i never saw throttle close on mine, who knows

The pressure and volume increases because the aftermarket pumps have a higher capacity of what it can pressurize, meaning when it lets the fuel in it's chamber, more fits under the amount of time it has before it strokes closed. So since it is moving more mass, the resulting pressure in the rail at WOT (when the return valve is 100% closed) will also increase. BUT, you must also realize that any cdfp will only be able to pressurize what it is given. It CANNOT suck fuel through the line any faster than the fuel is delivered to it. The itfp is rated at ~155lph at it's open loop voltage, and that is the absolute most anyone is going to get to their cdfp to pressurize with out taking further measures. There's absolutely no way around it that it will have to be upgraded as well to reach much higher numbers.

so being your the only one with an ITFP upgrade, are all the AM pumps capable of more flow/pressure if the INFP is upgraded?

Don't get me wrong. The cdfp is deffinately in need of upgrading sooner than later, but it can only go so far before it's not getting enough fuel to keep up with that higher demand. I haven't the slightest idea where or when that breaking point is, but I imagine there are some who are getting close. Like I said last year, I'm working from the bottom up.

Thanks !!! Exactly what i was looking for. So you increased the volume of the pump which in turn stabilized the pressures correct ? If so , 40 - 50 % is plenty of ffuel.

Harry

makes perfect sense an a very good point. The helper pump needs to be high flow also. I would recommend the 300zx Denso pump which flows more than the walbro and is significantly quieter and more reliable. Any pics of the intank pump from the ms3 ?

Harry

I can take pics of my MS6 itfp sitting on my dresser. Whoosh was able to get hard numbers on the unit a while back. I'll see if I can dig that thread up on 6club later tonight.

nice info!

155 LPH = 40 GPH, that comes out to 240lb per hour (rounding)

BSFC states that 240lbs per hour would equal 480 Crank HP at a BSFC at .50 (based on HP)

Now we all know that motors do not run at 100% efficiency. So for a gas motor you have to calculate a 12% loss due to heat and other items (like the belts, oil pump, timing chain, ect). So take 12% off the 480 Crank HP and you have 422.4 Crank HP.

Now, there is restrictions in the fuel system. The 155 LPH pump is not going to be 100% efficient in getting all the fuel volume to the DI pump. This is normally caused from the filters in the system, choke points, and bends and turns in the system. I would safely say that this is 6%.

So we take the 422.4 Crank HP and - the 6% you end up with = of 397.05 Crank HP

The stock pump is only good to 380 ish WHP and in a perfect world I would say your good to 400 WHP. I have not taken specific gravity of the fuel nor the different weights of fuel into consideration. It would be safe to bet that much over 400 WHP on your car is going to end bad for the fueling solution. We need a ITPU and if you guys can be patient, I am going to have the cure all for you here soon enough.

It will be a dual in tank set up running a regulator with return line. The feed line will be 8 AN to the DI pump with a custom billet piece for the DI pump itself. We are not going to be excluded from neededing a return line on our cars because we have direct injection. We need more volume and more pump to feed the motor based on BSFC. You can not argue with simple physics, you need the fuel supply to be there to generate the power, this is why everyone runs huge amounts of meth that is making over 400 WHP right now and if they are not, they have to be running on the brink of the fuels systems capacity or they are not telling the whole story on there mods.

Damn I am good, I didn't even look at whoosh's post and I am only off by 5 lbs total. So much for my rounding.

So would we be able to keep our current hpfp? Would that need to be changed out? I would like to keep my current hpfp if possible ! :)

Yes. I think that if there was ample supply to the stock HPFP it would work better. A few have installed ITFP with huge success, I can only see going bigger with a better feed side on the HPFP being a win win for everyone.

This thread panned out very well, thanks for all the answers guys!

good reads good reads