Injectors For Gtr

[Mik]

The 600cc injectors on my GTR are well and truely maxed.

I am after a set of injectors (probably somewhere around 700-750cc) that will fit straight into the factory rail and plug into the factory loom.

I don't want to have to mess around.

What can I use?

Also, will a nismo fuel pump flow enough to service these injectors. IIRC, they flow 276L/hr.

6 x 750cc injectors -> 4.5L min at max duty

-> 270L/hr

So, the fuel pump should be okay because the injectors will never see anywhere near 100% duty anyway.

Another option is to up the rail pressure, but I'd rather just get the injectors if they are a direct fit.

Would I be better off using a HKS or Trust rail and injectors?

[pnblight]

The 600cc injectors on my GTR are well and truely maxed.

I am after a set of injectors (probably somewhere around 700-750cc) that will fit straight into the factory rail and plug into the factory loom.

I don't want to have to mess around.

What can I use?

Also, will a nismo fuel pump flow enough to service these injectors. IIRC, they flow 276L/hr.

6 x 750cc injectors -> 4.5L min at max duty

                            -> 270L/hr

So, the fuel pump should be okay because the injectors will never see anywhere near 100% duty anyway.

Another option is to up the rail pressure, but I'd rather just get the injectors if they are a direct fit.

Would I be better off using a HKS or Trust rail and injectors?

<{POST_SNAPBACK}>

the 700cc sards go straight in and are a good injector for the street driven gtr

the nismo fuel pump should be fine for these injectors if you run close to std pressure as my std pump services them up about 80% duty at ~530rwhp so a nismo pump should be fine at the same pressure but if you turn up the pressure the flow capiability of the pumps reduce accordingly.

pete

[Topaz]

do your 600cc injectors tick?

is that how you know they are maxxed?

whats the size of the std GTR injectors?

sorry about all the questions its just that mine are ticking and its pissing me off

I would like to change mine to a bigger set, but I have no idea what to look for or the prices!

help appreciated

Tom

[Mik]

the 700cc sards go straight in and are a good injector for the street driven gtr

the nismo fuel pump should be fine for these injectors if you run close to std pressure as my std pump services them up about 80% duty at ~530rwhp so a nismo pump should be fine at the same pressure but if you turn up the pressure the flow capiability of the pumps reduce accordingly.

pete

<{POST_SNAPBACK}>

Thanks Pete...so the plugs are the same too? If yours only run at 80%, they should be big enough for me.

[Beer Baron]

i think the real question here is "how much do you want for those 660s"?

[Mik]

i think the real question here is "how much do you want for those 660s"?

<{POST_SNAPBACK}>

A better question may be..."how much do you want to pay for them?"

[Sydneykid]

Also, will a nismo fuel pump flow enough to service these injectors. IIRC, they flow 276L/hr

Is the 276L/H at 12 volts or 13.8 volts?

Do you have a separate relay and wiring back to the battery for the fuel pump?

Or are you still using the factory wiring?

cheers

Edited August 25, 2005 by Sydneykid

[Mik]

Is the 276L/H at 12 volts or 13.8 volts?

Do you have a separate relay and wiring back to the battery for the fuel pump?

Or are you still using the factory wiring?

cheers 

<{POST_SNAPBACK}>

No idea what voltage the pump is rated at, but I'm guessing it would be at more than 12.5 volts.

I was considering running a seperate relay some time ago, but the thing is, on the BCNR33, with the battery in the back, there is only about 1/2m of cable between the battery and the fuel pump anyway.

When I saw this, I measured the voltage drop and it was less than 0.1 volts...Hardly worth the effort.

I suspect that doing this will be much more worthwhile on a BNR32, since the battery (and fuel pump relay at a guess) is at the front.

[Sydneykid]

No idea what voltage the pump is rated at, but I'm guessing it would be at more than 12.5 volts.

I was considering running a seperate relay some time ago, but the thing is, on the BCNR33, with the battery in the back, there is only about 1/2m of cable between the battery and the fuel pump anyway.

When I saw this, I measured the voltage drop and it was less than 0.1 volts...Hardly worth the effort.

I suspect that doing this will be much more worthwhile on a BNR32, since the battery (and fuel pump relay at a guess) is at the front.

<{POST_SNAPBACK}>

Interesting, how did you measure the voltage drop?

On a 1996 R33GTR, if I measure the voltage at the positive terminal on the battery with the engine running at 6,500 rpm on the dyno under load, it reads 13.8 volts.

If I measure the voltage at the positiive terminal on a Bosch 044 fuel pump, same conditions, it reads 12.3 volts with the standard wiring harness.

If I measure the voltage at the positive terminal on the same fuel pump under the same conditions, it reads 13.8 volts with a relay and a 30 amp wiring (with fuse) back to the battery.

With a lift pump, surge tank and a pressure pump, the voltage drop is even more noticeable via the standard wiring. You can even fell the wiring harness get hot when the pumps are working hard.

cheers

[Mik]

Interesting, how did you measure the voltage drop?

On a 1996 R33GTR, if I measure the voltage at the positive terminal on the battery with the engine running at 6,500 rpm on the dyno under load, it reads 13.8 volts.

If I measure the voltage at the positiive terminal on a Bosch 044 fuel pump, same conditions, it reads 12.3 volts with the standard wiring harness.

If I measure the voltage at the positive terminal on the same fuel pump under the same conditions, it reads 13.8 volts with a relay and a 30 amp wiring (with fuse) back to the battery.

With a lift pump, surge tank and a pressure pump, the voltage drop is even more noticeable via the standard wiring.  You can even fell the wiring harness get hot when the pumps are working hard.

cheers 

<{POST_SNAPBACK}>

Hmmm...I think the issue may be that the 044 draws much more current than the OEM pump...and this is compounded when you run two pumps off the oem wiring. But 1.5 volts drop seems huge for such a short cable. Maybe the ralay on that car was on the way out?

I measured the voltage at idle...but this shouldn't make a difference, becasue if anything, the pump will draw more current at idle, because it is under slightly more load.

On another note, I considered using an 044 and a surge tank setup. But my question is, will my oem pump keep up with the 044 (in order to keep the surge tank full?) I know it will not face any presssure, but will that increase the flow by that much?

Wih that setup, I would definately run thicker cabling, hot wires and fuel in a boot aren't a good mix!!

[Amaru]

On another note, I considered using an 044 and a surge tank setup. But my question is, will my oem pump keep up with the 044 (in order to keep the surge tank full?) I know it will not face any presssure, but will that increase the flow by that much?

Wih that setup, I would definately run thicker cabling, hot wires and fuel in a boot aren't a good mix!!

<{POST_SNAPBACK}>

I run a stock pump in tank lifting to a 2L surge tank and then an 044 and it has run on long dyno stints etc without a problem at all. I am also running Sard 700cc injectors.

Stock pump is being powered by standard wiring + relay, 044 has its own wiring.

Pics of the whole shebang...

Shebang #1

Shebang #2

Edited August 25, 2005 by Amaru

[Cubes]

I measured the voltage my pump was receiving today.

11.1v using the supplied earth at WOT.

11.68v using the chassis as the earth at WOT.

~12.6v at idle. Still a little low, it should be what the battery is, 13.8v.

Battery is at the front, running the std. internal pump with an external bosch pump.

At WOT you are running a higher fuel pressure. (Base pressure + boost entering the engine). Higher fuel pressure at WOT = higher fuel pump load and current draw at WOT.

Edited August 25, 2005 by Cubes

[Mik]

I measured the voltage my pump was receiving today.

11.1v using the supplied earth at WOT.

11.68v using the chassis as the earth at WOT.

~12.6v at idle. Still a little low, it should be what the battery is, 13.8v.

Battery is at the front, running the std. internal pump with an external bosch pump.

At WOT you are running a higher fuel pressure. (Base pressure + boost entering the engine). Higher fuel pressure at WOT = higher fuel pump load and current draw at WOT.

<{POST_SNAPBACK}>

Will Sard 800cc injectors fit into the standard GTR rail?