14 psi on the Greddy Kit made 573rwhp on a Dynojet in my car, and averages around 540rwhp or so for guys not tuned as aggressively.

I feel better now

Like we spoke about on the phone, gonna need some larger injectors ASAP!

 

phunk, to make 573whp, do you have a modified S1 fuel system or the new S2 fuel system on your car?

 

Nismo350zRT, my car had the original prototype system on it, the first one we made. It was the S2, because actually that was all we had for a long time. We came up with the S1 because the S2 was extra install time and extra parts that most guys dont need.

The record on our S2 kit is held by SGP, who made 678rwhp Dynojet with it (without using any type of fuel pump booster). They reported it was the ABSOLUTE max. Of course, with a Voltage booster to the pump, they could have got more. That is a common fix many times for those who dont want to go all the way to twin pumps... but it does of course reduce the life of the pump. Research the MSD BAP (Boost-A-Pump) for more information. A BAP would be able to cram more thru the S1 kit as well.

There are 345345 ways to get to the same place!!

 

After talking to my installer (Cantrell Motorsports (plug plug)) we will schedule some time in a couple of weeks to check the wiring to the pump and to install the S2 if that's needed, I'll give you a shout when that's gonna happen.

If the fix is as simple as a couple of hours labour then I'm gonna do that as soon as I can ... although I won't have the funds to get the car back on the dyno for quite a while.

I also think it will be an interesting opportunity to see how much MAX power on 550's is .... info is power

I just need to find a way to justify another 10k so that I can do heads, cams, injectors and a new intake plenum so that we can really see the full potential of a non-sleeved block ...

Colin

 

So here is what I tried, I'd be very interested in people opinions ...

I spliced a 10gauge wire from battery to a relay 12v in and a 10Gauge wire from relay out into the fuel pump wiring just before the connector :-



I used 10gauge to ground the relay and used the existing fuel pump 12v as the relay switch signal.

The only thing that I didn't do was to run a 10gauge for the earth to the fuel pump earth, does anyone think that this might be a problem??

Once this was done I took the car out and here is what I found, 11.5 across the board at 15.5psi, which is still too lean at that boost level (I'm looking for ~11.1).

But given how that fuel table curve looks, this still doesn't make sense, I'm adding a load of fuel after peak torque when it should be starting to reduce as the air intake is reducing.

So, I pulled into a parking lot and re-connected the stock fuel 12v into the connector, so basically returning the wiring the stock and took it for a few runs and found that I got exactly the same readings, 11.5 across the board.

So, this leads me to believe that when we had the car on the dyno right at the end of 4 hours hard running I think that the fuel pump may have been over heating or something ...

Also, because given how much fuel we are adding the AFR did not get super rich like it should if the fuel pressure was holding with peak RPM, this makes me think that the problem is still not fixed and that the fuel pressure is STILL dropping with rpms ....

Here is what my current fuel table looks like graphically (I still need to tidy it up but I'm not gonna even try until I get the fuel delivery problem fixed) ... the yellow line indicates what the fuelling SHOULD be doing ...



So, I'll be looking to upgrade to stage2 fueling to see if that fixes it.

Colin

 

I just found some videos on YOUTUBE of the NEXUS gauges......damn, they are loud. They sound like the exhaust cutout motors I have!

 

Does anyone know the max psi that a CJM stage 1 kit and stock hardlines can sustain at redline?

Colin

 

Hmm...my Nexus gauges are very quiet. The only time I can hear the stepper motors is during the power up/down sequence. But I guess that's because the motor isn't running at that point. When I'm driving, I can't hear them at all. Colin, your G must be alot quieter inside than my Z.