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Fuel Injector Scaling

Posted: Thu Sep 12, 2019 9:44 pm
by Jasonvictory86
Hi!
I've got a 2009 Fit 5-Speed that I just turbo'd.

The stock tune says the injectors are 310cc but they're actually 277cc. I tuned my fuel to compensate for this but I want to step up to the RDX 410cc.

When I put in the "old" (310cc) and "new" (410cc) injector sizes, the car doesn't start. And yes, I changed the injector dead times.

When I save the tune, close, and re-open the tune it still says the same old and new sizing. Shouldn't this put the 410 into the old and new spot once the tune is re-opened?
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Fuel Injector Sizing
(4.61 KiB) Not downloaded yet
Thank you!
- Jason

Re: Fuel Injector Scaling

Posted: Thu Sep 12, 2019 11:44 pm
by KTuner
Feel free to use the individual cylinder trims to offset the difference. The new and old size is not relevant other than the math for such a thing.

Re: Fuel Injector Scaling

Posted: Sat Sep 14, 2019 6:57 pm
by Jasonvictory86
KTuner wrote:Feel free to use the individual cylinder trims to offset the difference. The new and old size is not relevant other than the math for such a thing.
So if I put in the old / new values in the "injector sizing" field does it make changes to the individual cylinder trim numbers?

And if it's supposed to, do I need to save, close out of ktuner, and re-open the new tune for the values to change?

Thanks!

Re: Fuel Injector Scaling

Posted: Sun Sep 15, 2019 1:07 pm
by KTuner
It's a separate set of settings.

Re: Fuel Injector Scaling

Posted: Sun Sep 15, 2019 3:47 pm
by Jasonvictory86
KTuner wrote:It's a separate set of settings.
Is there a way to verify the parameters have been applied?

Right now if I change the “old” to 310 and “new” to 277, nothing changes with my air/fuel or short term fuel trims

Re: Fuel Injector Scaling

Posted: Sun Sep 15, 2019 4:11 pm
by KTuner
It would affect fuel pulse, but you can use the cylinder fuel trims in the same way.

Re: Fuel Injector Scaling

Posted: Sat Sep 21, 2019 12:19 am
by Jasonvictory86
For Main Fuel Trim and Cylinder Correction Fuel Trim, is that value the percentage between the old and new injectors, or is it CC capacity?

For my tune that's setup for 310cc and RDX 410cc, that's a 27% increase.

Would 27 (percent) go in the field or 100 (difference in CC)?

Thanks!
- Jason

Re: Fuel Injector Scaling

Posted: Sat Sep 21, 2019 6:23 pm
by KTuner
As an example, -10 would reduce by 10 percent.