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On 20/08/2021 at 10:24 PM, BourneToLive said:

I had already installed the ballast delete with the injectors. And I did research on the changes to Injector duty to compensate for the bigger injectors yesterday and gave it a shot. I set it to 52.1% at 0.06 and it stalled out any time I came to a stop, so I set it to 74.1% instead and it fixed that issue. Although, since my last tuner tuned the ECU to work with the 555cc injectors, I based my calculations on the previous injectors and came to ~64%. 48% turns the car and then shuts off immediately. 

If that's the case your existing tune is really really bad. You don't base the setting on what you already have - 100% represents 440cc and the setting change is done from there, end of story. I used to run Sard 1000cc EV1 injectors with zero idle issues with short pulse width on a D jetro power fc - setting for these were 44 - 45%.

If you are needing to be higher % you are just rescaling your entire fuel map richer.

You need to get on the dyno for a tune badly. Without a wideband it's all pointless.

  • Like 1
On 8/21/2021 at 8:58 AM, BK said:

If that's the case your existing tune is really really bad. You don't base the setting on what you already have - 100% represents 440cc and the setting change is done from there, end of story. I used to run Sard 1000cc EV1 injectors with zero idle issues with short pulse width on a D jetro power fc - setting for these were 44 - 45%.

If you are needing to be higher % you are just rescaling your entire fuel map richer.

You need to get on the dyno for a tune badly. Without a wideband it's all pointless.

I second this. Please get a wideband or throw it on a dyno with a decent tuner. 

 

Nah. You've got the tuning tool (the handset). Buy a wideband instead, use that to adjust the injector settings until you've got the scaling right (for the top end) and the dead time right (to get the bottom end right). Should only take a few minutes on the road with 2 people. Err on the side of rich at the low end, and aim for ~11.5:1 at higher loads. You just need to be cautious in how much load you put on in case it is lean when you start - but you can almost certainly set the scaling to where you know it is both able to run and quite rich from the various values you quoted earlier.

Then, assuming your original map has the cruise and transitions sorted out, you should be gold. The wideband will tell you whether it's any good or not.

On 8/22/2021 at 11:09 AM, BourneToLive said:

I just found this picture from when my tuner tuned my car. I’m not good at reading these things. 
 

1D0A3FA3-E8DD-4417-8E0A-6835801A088C.thumb.jpeg.1ec9226e105c3610641487885b8266a6.jpeg

Is there something you wanted explained or was there something you were curious about? 

There are plenty of resources out there if you want to learn about fuel or timing maps etc. 

  • 2 weeks later...
On 8/19/2021 at 7:51 PM, BourneToLive said:

I took my car to a tuner today and he said the injectors are too big for the PowerFC to handle. Told me to get a better ECU. 

Should be no worries im sitting on the dyno now  in a GTR with a powerfc and the same injectors, im happy to do up to 2200cc's.

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