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Has anyone tried running pressure reg. at the pump when using external pumps and surge tank.

basically a question about the lag in the line for the pressure reg.

I know that my old commodore had a similar setup but I doubt it was a rising rate reg.

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not a very good idea i'd say. for starters you'd have to run a vacuum line to the reg, if at the back of your car thats a long way, not to mention to press drop and delay in a vac line over that distance.

keep in mind also that the reg goes on the return line. so it could be possible to get pressure spikes in the lines with the reg so far away from the injectors/rail

The BA is one of them i believe.

As in the BA falcon? All australian fords run a return system.

There is nothing wrong with the non-return system - keeps the fuel cooler by not sending it to the engine unless it is needed. The reasons manufacturers do it so well is that they have a function of injector flow rate vs manifold pressure so that it compensates for the pressure variations across the injector so they dont need a fuel system that changes pressure. Other return sytems like what nissan use is a fuel pressure regulator that varies the pressure relative to the manifold pressure to compensate for the pressure differential across the injector.

Both systems have their advantages and disadvantages.

i converted the supra below to a returnless rail.... not cause i wanted to though but because i had to due to the -10 lines and aeromotive gear :P no advantage just more work. the r33 system works well up to 380odd kw the GTT is another issue and can sometimes cause dramas.

post-34927-1194831575_thumb.jpg

I see that ur reg is still mounted in the engine bay, uras. Are u twin feeding the std rail? if so that should be of some benefit, well would be on a gtst at higher power levels

I see that ur reg is still mounted in the engine bay, uras. Are u twin feeding the std rail? if so that should be of some benefit, well would be on a gtst at higher power levels

yeah -10 feed -8 return. No benefit on a GTS-T. in fact i hate aftermarket regs on any gtst under 350rwkw aswell, id rather customers but the money they used on the reg on a better pump as the std reg is killer.

Can the std reg go farther than 350kw say if you remote mount it and twin feed a custom rail, I guess if you were to go to that much effort u'd prob go aftermarket. Basically a question of how much fuel can the std reg flow.

the new commy engines both v8 and v6 are returnless along with a heap of other cars.

i've read a few articles where people have modified the system in the tank with the reg, but it hardly seems worth it to change a vehicle to this setup unless its already the standard system on the vehicle that your working with.

the returnless fuel system architecture eliminates fuel system recirculation, this design minimises fuel heating, reducing fuel tank temperatures and consequent evaporative emissions. an integral pressure damper is used inside the fuel rail to reduce noise.

so unless your worried about emissions, lol...

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