Alright, I got called out on my math by l2r99gst and he was correct. I accidently figured these HP levels at 80% like you would a duty cycle on an injector. So, I made a mistake

The original post #1, will be fixed immediately to reflect the correct information.

Sorry for the mistake, I used the wrong damn formula.

 

Dave,

Would you share the formula you're using for calculating the flywheel HP that the pump will support?

All formulas make some assumptions that generalize among motors. My calculations for flywheel HP produce lower supported HP numbers than your formula apparently does, but as long as everyone understands that these don't relate directly to dyno numbers, we're all on the same page. Drivetrain losses would reduce the flywheel numbers by 17-25%, depending on the 4WD system, so 600HP flywheel might translate to 480HP measured on the dyno...

What was useful to me in reviewing your numbers was (1) that there does not seem to be much difference in availalbe fuel volume flow comparing the stock Walbro and the HO Walbro,unless you're running more than 40 pounds of boost and (2) that even using your HO modified Walbro, your direct dyno experience was that you documented fuel starvation effects at around 500+ HP dyno HP at the wheels. You adjusted the fuel curves and used bigger injectors to work around the problem before the dual pump solution, right?

 

No biggie, Dave. I figured you added in some sort of safety factor into your calculations, like any great tuner would.

Thanks for the great product and all of the testing that you put into this.


Eric

 

i know what im buying. thanks dave great write up. ive been looking into a twin pump set up to fuel my stage 3 head and turbo upgrade.i guess ill be calling jarrod
great job as always

 

well i can see where my money will be spent. truly gangster david!

 

Great write up Dave!

 

Great write up! Very clean looking double pumper setup.

 

thank you for ALL your time spent and given back to the Evo community !!

 

The BSFC I am using is .6. Simply take the lb/hr and divide by .6.

Yes, I was able to get the car to run/make power with a much larger injector than the car needed even with the pump falling off.

 

Could this be modified to use a different sized pumps?

 

I personally like the FullBlown system better, its a complete CNC top which replaces the entire stock plasic (crappy) setup. Its also cheaper, and it gives you options do use -10an stainless lines instead of stock rubber lines.

 

just a problem of it can be retrofitted to fit the denso 50mm supra twin turbo 1040 pump or whatever it's called.

 

^^ Yup, that is the question. I did a little searching, the model number is 195130-1020, I guess RRE sells them. Denso has them listed at $190.00 MSRP on their site, so not bad at all. Suprisingly E-bay had them for $235.00.

I'm hoping either the Buschur unit or Full Blown unit can be modified to fit a pair of them, or single depending on needs. CO_VR4 was sending Full Blown a 1020 to measure and whatnot.. (I hope..)

 

From Walbro's own testing they show the 255 rating (255lt/hr=67gal/hr) at 40psi and 13.5V not 0psi. This from http://www.autoperformanceengineering.com/
Look in the left column and click technical then check out the 13.5V table. GSS342 is the "high" pressure 255 listed. Also shows a pic of the GSS340 (left), GSS342 (middle), and GSS341 (right).

 

nice to see even more fuel options out for the evo...