Le me see if I am following this correctly now,

The Walbro *does* work w/o an FPR and the plugs *were* the right length?

I cancelled the order because I had a horrid experience with the ZEX p;ugs that were too short causing erractic dynos and KR it was all documented here a year ago.

Can someone please clarify which works, the Denso or the Walbro 255 , whether you need an FPR and whether the plugs I listed were the right ones?

I can get the pump on EBay is it Universal and will it fit in the plastic stock sleaving the SARD wouldn't.

Thanks all!

 

The Walbro 255 will fit in to the stock mounting position with only a small bit of modification to the mounting rubber seat. The line pressure will go up from 3.5bar to just over 4.
Mine was very noisey but maybee I didn't get the insulation rubber in quite right. The problem was it just failed after 3 race meets.
The Denso unit is a simmiler size to the Walbro & has to have the same mods done to fit it (nothing dramatic) & it runs the same pressure as the OEM unit
I am at home now & dont have the model # but I think it was from a GS430 & cost about A$250 aftermarket

 

has anyone else heard of walbro 255 failing? every tuner I have talked to has good thing to say about this unit.

 

The Denso unit is a simmiler size to the Walbro & has to have the same mods done to fit it (nothing dramatic) & it runs the same pressure as the OEM unit


I guess I got lost somewhere, but why would you want the denso unit just to have the same pressure as the OEM unit?

 

The OEM unit looses pressure at high RPM & load. The Denso unit
holds the pressure. The pressure is controlled by the intank pressure regulator, the problem with the Walbro unit is that its output is too good & the pressure regulator can't cope & the rail pressure raises it about 8psi.
This is probably not a problem for the FI cars but the pump sure works hard pushing the excess fuel through the regulator & the noise level from the pump is quite high.

 

I dont think the noise is due to the pump overcoming the stock reg. The pump flows 75% more fuel than the stock pump, so it reasons to stand that the electric motor is stronger and hence...louder. You are correct in that the Walboro will raise pressure, and this is exactly what I want. So even when the fuel pressure drops at higher RPM, it will still be greater pressure than the stock unit.

Realize that swapping the pump is not the ideal solution, but it is an inexpensive way to gain more fuel pressure for F/I cars. There are better options, but they are more involving.

 

Just to clarify a few things. The plugs are not too short they are perfect (NGK Irrads.) I have them so don't believe everything you read it isn't always true.

Also if you use larger injectors and add more fuel (I do it at the ECU level) you will not run lean with the stock pump until around 7k rpm's in first. I have the video to prove it and I am running 9 PSI.

Peas!