[mitch32]

Hello,

I have a R32 GTR. So I'll first tell you whats on the car currently,

Right Now,
Apex'i Power Intakes
Kakimoto Stainless N1 Cat-Back Exhaust
AP BOVs (HKS clones, but I ordered a new BOV)

I have already order, should arrive in the next few days,
2 X GT2860-5
Apex'i AVC-R Boost Controller
Synapse Synchronic BOV that will be used as a recirc valve
Supra TT Fuel Pump (Denso Part#950-0155), 300lph

Now I know I need to order some injectors but I'm unsure the size, I want to keep the stock fuel rail and fuel-regulator. I can modify the bore of the fuel rail to accomidate bigger injectors (I have use of a milling machine) but I don't want to heavily modify the rail.

I also am trying to find good gauges, I think I'm going with a Defi DIN Gauges (Oil Temp, Water Temp, and Oil Pressure). I may also go with a Oil Cooler but haven't decided yet.

Right now I'm looking for around 400hp, but I will end up rebuilding the engine and I want to have headroom, so let me know if I need anything else and what injectors to get. I can get RC Engineering Injectors pretty easily, are they good? what size? what type?

Thanks in advance,
Mitch

 

[Sub Boy]

Hi, There is HEAPS of posts on 2530's/2860-5's and what to run with them....Go the search function.

400hp is nothing for -5's....500hp at all 4 wheels is easy.

general consensous is that 700cc injectors (I have 550cc's and run 520hp at all 4....but they are getting to the end of the scale), Bigger in tank pump (Nismo or Tomei) or leave the pump and add a 044 bosch with tank.
If you want to retain the factory fuel rail you can use a Nismo Fuel pressure regulator, It looks exactly like a factory one, but has a bolt in the top to adjust pressure....And they are cheap to buy.

 

[mitch32]

Thanks for advice, my engine isn't forged that's why I'm aiming for 400hp. My engine has amazing compression ~165psi on first 5 cylinder and 170psi on the 6th. Also I'm not sure if the head gasket has ever been changed so I'm going to try to be conservative and aim for 400hp. I'm going to read about fuel pressure regulators I've heard different opinions.

 

[Floyd]

Mines use the stock fuel rail on their 500hp engines, there is no capacity problems at that power.
As you will probably want more power later, I would buy some injectors in the 700cc range. That will give you plenty of headroom in the duty cycle.

Personally I've gone for a rising rate fuel reg.

 

[ru']

Nothing wrong with stock fuel rail and regulator imho; just get injectors which fit it (easy) capacity as above. Don't worry about the standard head gasket either.

400 hp is nothing, especially if it's a flywheel figure we're talking about.

 

[mitch32]

Nothing wrong with stock fuel rail and regulator imho; just get injectors which fit it (easy) capacity as above. Don't worry about the standard head gasket either.

400 hp is nothing, especially if it's a flywheel figure we're talking about.

400hp at the wheels I'm looking for. Which injectors at 700cc's fit the stock fuel rail? I can't figure out how to figure out sizing and how to find what fits.

 

[ru']

Sizing goes roughly 1cc per bhp (flywheel) for the RB26.

As far as what fits, buy ones specifically for the RB26 fuel rail.

 

[herman]

upgrade

sard 700cc injectors are a straight drop in.id leave the fuel rail and just get a nismo 280ltr intank fuel pump,thats my 2p worth anyway.good luck wiyh the work mate..

 

[tyndago]

700/720cc injectors give you plenty of headroom. You want headroom with an engine that turns to 8000+ rpm. Use Denso injectors. Its the same that SARD, Blitz, HKS,Greddy all rebrand. They work, and are drop ins.

You don't need to change the regulator. Stock fuel pressure is ~42psi with the vacuum line off, and its a factory 1:1 regulator. You don't want to mess with any variable rate, or other weirdness unless you have to do it to overcome some other issue. More fuel pressure means more fuel out of the injector, but some pumps have issues handling more pressure. ie 42 psi fuel pressure plus 20 psi of boost pressure means 62 psi of fuel pressure that the pump needs to pump. As pressure goes way up, flow starts to decrease.

Heres a great page on fuel pumps - Stealth 316 - Fuel Pump Upgrade Guide