thanks Hal - yes, let us know the answer to the above, I can easily retrofit a sensor into my pan if the ecu will recognize it

 

Rcdash - No, that is not the case.

Z1 - Rather than trying to retrofit etc, just add the PNP racepak sensor to your dash

 

thats an option as well

 

Hal can you post the injector dead times for the PTE 1200 and 1600cc injectors you are using on your street and race car? gotta order 1 set or the other.

 

Hal, what's your take on folks (e.g. str8dum1) just bumping fuel pressure a bit (3 bar to 4 bar say) rather than upgrading injectors? I figure atomization will be better at the slightly higher pressure and it's not as though that's ridiculously dangerous pressures for the hoses, fittings, etc... I wonder if the CJM twin pump could handle it. If str8dum1 wants to run 25 psi, at 60 psi base, that would be 85 psi. That's seems really high, but Increasing the fuel pressure by 33% (40 to 60 psi) would result in a net power increase of only 16.5% (I believe doubling the power requires quadrupling the pressure). Perhaps that might not seem worthwhile given the added stress on the pump, but starting at the 700 whp level (1000 cc injectors), it would take you past capacity for 800...

 

This can work in some situations, but having enough fuel supply requires special attention on the 350Z/G35. As you mentioned, doubling fuel pressure does not double the amount of fuel going in the engine - rather it is the square of the difference (Only ~41% gain if you double fuel pressure). Next thing to note, as fuel pressure goes up on a walbro, the flow decreases significantly.

 

Sorry for the OT question, but that answer was enlightening - thank you. I had no idea flow and pressure were related *inversely* for the walbro. I don't understand it, but I'll do more research. At 0 psi how can it flow nearly 80 gallons per hour?

 

No problem. I wish it was not the case, or I would crank fuel pressure to overcome injector issues more often. Other applications with less complicated fuel tanks and big aftermarket pumps are easier to work around. I don't have a flow chart but I know the bugatti veyron pump I'm using in my car is rated the same from 2.5 to 8bar.

At 0psi how can the Walbro flow 80gph? Unhook all hoses from it and just let it pump freely. It would move ~80gph at 0psi.

 

Wonder why APS sets their fuel system for 4bar out of the box and it does not have any negative effect on their system. why would it be on something like lets say CJM/AAM FRS?

 

One issue you will see with the APS extreme fuel system, is their injectors are rated at 4 bar, but to have enough fuel to support that with twin walbros is beyond their capability. This is taken from our previous dealings. You would also have issues with their venturi design since base fuel pressure, I believe is 50psi. I can't remember exactly as this was done some time ago.

 

bump for the answers

 

Don't have them handy, and I'm not sure if Precision has them. I have some proprietary values I have come up with that are working for my needs but I would hunt down the values or send the injectors off for mapping before advertising values.

 

Thanks,

i got proprietary values from a tuner at PTE. all set now.

 

Nice little feature for anyone trying to go with the Racepak IQ3 dash. We just ordered two of these to come up with a nice mounting solution. They are full ABS plastic with a carbon fiber "faux" print. They aren't that expensive and I believe they run under $100 each.

 

Will the Racepack fit in the cubby of an 08 Z?

 

I'm guessing this is the same way that I would need to set it up for a 02-03 Maxima with the older VQ35 ECU since it doesn't have the same connectors as the newer ECUs, correct?

I currently have a UTEC hardwired into my stock harness as it stands and when I get more serious with build it would be great to have VTC control and all the tuning options available through the haltech. Would I be able splice it into the stock harness/ECU in the same manor that I have with the UTEC so I can let the stock ECU run the car during closed loop and still pass OBDII? Thanks for your time!

 

I haven't tested it on the 08, but I don't think it fits on the 03-06. We took the cubby out of my drag car and cut a piece of ABS plastic to fit instead. Now with Racepak's solution, it will be even easier.

 

Correct, you can splice into the wires to take control of fuel, ignition, cam timing, etc.

 

Cool, I'll probably go that route pretty soon.

 

they need something for the G35!