tell me this is the truth...

 

So, who is correct... Are these 245 lph Denso or Walbro fuel pumps?

 

the world may never know

 

I called them up, and they claim that the 245 lph pump is a Denso unit.

 

so is this a legitimate unit that can be used in the evo?

 

There is a Denso built 245LPH pump in stock 38mm size. (NOTE: this is NOT the Denso Supra TT 50mm pump, that flows like a trooper). AP Boss sells them, and they are built by Denso, in batches of 100 or so, to AP's specifications, and cost around $250 each.

I obtained one for testing, and sent it to RC Engineering for flow testing. At 13.5V, it flows 245 at 35 PSI, and about 220 at 45PSI, decreasing with additional pressure, as most pumps do, to around 167LPH at 75PSI (approximately base fuel pressure + compensation for 30 pounds boost).

By comparison, the Walbro 255HP flows around 220LPH at 75PSI, according to RRE testing. http://www.roadraceengineering.com/f...pflowrates.htm

So, the Denso pump does not flow as much fuel at higher pressures as the Walbro does, and certainly not as much as the modified (H.0. from Buschur) Walbro does, but it is a Denso OEM quality pump, which is quiet and I assume has the well known Denso reliability.

 

so....the denso unit would flow a lot less at 75 right? isn't that bad?

 

interesting

 

Interesting indeed.

At 75psi the PE 245lph flows 55l more than the stock unit, but still 53l down on the Walbro 255lph.

According to the flow rates in the thread below the 210lph outflows the PE 245lph at higher pressure and is only 20l down on the Walbro at 75psi.

https://www.evolutionm.net/forums/sh...=117228&page=4

It would be good if these figures could be varified with another test. I wonder if the 210lph is a high pressure pump, or possibly the figures are incorrect..?

Has anyone tried/tested the Sard 235lph or 265lph pumps? I can't find any details on these and was wondering what size they were and who made them.

 

Yes. It is 38 mm diameter, and is very likely the same pump that CO_VR4 described. Not sure what electric adapter plug is included with it.

 

My comment was simply stating what the AP Boss Denso pump test showed. I have not tested the PE 245 pump.

 

Its less than a Walbro at 75 psi, but still much more than the stock pump. It would be fine for any Evo with a stock turbo.

 

AP Boss also sells a very well made heavy duty replacement wiring harness.

 

Still plenty of fuel for most of us:

167 lph = 2.78L/min
1000cc= 1L, so 2.78L/min = 2780cc/min
2780/4 = 695cc/min

So, this pump would still deliver enough fuel at 30 psi of boost to supply 700cc injectors.

Or, to put it another way, assuming a 12:1 AFR, at 30 psi, the pump could support the following amount of mass airflow:

2780cc/min*.76=2112.8g/min fuel
2112.8g/454=4.65 lb/min fuel
4.65 lb fuel * 12 = 55.8 lb/min airflow

so, this pump would be able to support 55.8 lb/min of airflow at30 psi boost, or roughly 560HP (at a 12:1 AFR). Should be good up to a turbo with a 55lb/min compressor, which includes 50 trims, 20gLT, some gt30s, etc.

At 11:1, the support would be 4.65*11, or ~51 lb/min of airflow. Still enough for most of the turbos mentioned above.


Eric

 

sounds like a good alternative