Nismo Adjustable FPR, is it worth it?

[FlawleZ]

I'm sorting through what I can and can't afford at the moment with my new motor I'm about to drop in my car and I'm really debating whether or not I should consider the Nismo FPR. At first I'll be running a T3/T4 with stock fuel. Now, as I understand, the stock fuel pressure regulator maintains ~37 psi for the specified 260cc injectors. Is this rating 260cc@37 psi or are they 260cc@50 psi? I know there is untapped potential using the romulator by increasing the duty cycle of the stock injectors, but how beneficial would the Nismo FPR be with/without the romulator?

[Jason84NA2T]

Any adjustable FPR is only going to give you the ability to raise or lower the fuel pressure, it in and of itself offers no performance advantage. Stock injectors are 259cc/min at 37PSI. You can get ~20% more fuel out of the injectors by raising the ttpmax, and another 20-25% on top of that by raising the fuel pressure.

You can make a stock FPR adjustable, or crush it slightly to run a few PSI over stock. I really don't think you or anybody else needs an adjustable unit until much later in the game...

[FlawleZ]

So then would you suggest me crushing or modifying my stock unit to be adjustable in my case? I do plan on upgrading the rest of the fuel system in the near future, but I want to get the most out of what I already have.

[Jason84NA2T]

I would crush it, if you have a spare you can modify it to be adjustable fairly easily. I know Obso cut the top off, riveted on a bearing cap and sealed it with JBweld. Guido also did it for his GRM challenge car:
http://www.worldsfastestclown.com/2002fuel.html

I have one I crushed to raise base pressure to around 57PSI. This was probably all the walbro is capable of handling with a 420cc injector anyway, but should be more than fine with stock flow rate injectors.

By the way: whoever tells you that you should not run higher fuel pressures is just being silly-stupid. They think of every excuse in the book as to why it's "bad", but all it boils down to is the limitation of the pump to supply both high flow and high pressure.

[FlawleZ]

Alright well I've decided to raise my fuel pressure and keep boost at moderate levels until I'm able to upgrade my fuel system. So, what would the limits be in terms of fuel pressure? I'm not really looking to push them, I would just like to know.

[zmech]

fpr

z

[G-E]

I purchased the Nismo fpr for my 50th and it works fine. Bought the one for the Z32 I think it was.

http://www.courtesyparts.com/Merchant2/ ... 70-RR710US

I can get 50 psi out of it easily on the stock fuel pump.

that's fugging hilarious.... the nismo fpr is like the clown's homemade one but shinier

and a rule of thumb with fuel pressure:

higher fuel pressure increases the size of your injectors, and reduces the size of your pump

s/size/flow/

[Jason84NA2T]

G-E wrote: that's fugging hilarious.... the nismo fpr is like the clown's homemade one but shinier

So the shiny one is a $170 up-charge?

DIY stuff not only makes my day more enjoyable, but I get those strange sense of accomplishment for some reason..

[Shen_VG30ET]

there are plenty of "nismo" alternatives out there that do the same thing(or better) for far less. Ive come to learn that if you are going to buy nismo, alot of the cost is the name

[G-E]

and TRD isn't ?

[Shen_VG30ET]

G-E wrote: and TRD isn't ?

TRD? as in Toyota racing development? dont get much into toyotas aside from my wifes horribly slow corolla