Injector Size and Idle

[CW FL5 CTR]

Would 345cc Prelude VTEC (94-96) stock injectors cause idle issues with the stock ECU? I have a P28 chipped ECU that will idle fine, but when I hook up the stock '98 ITR ECU to my '98 ITR it idles super low and stalls out if I don't give it gas.

Also, does anyone know the "dead time" for the stock Prelude injectors, need that parameter for SManager. Thanks!

[GeHonda]

Dead times can be seen here:

https://www.phearable.net/information/t ... wzyWDF34m9

Looks like, assuming that data is accurate, that the prelude injectors have a shorter dead time, meaning that they flow more for a given signal, like for like.

Considering that their flow rate is ~40% higher already, and then you have the shorter dead time, you might be well over 50% more fuel at idle.

[CW FL5 CTR]

Thanks GeHonda! In SManager the voltage sequences at 0.00, 8.09, 10.11, 12.13, 14.16, 16.08, and 24.55. But in the Phearable dead times chart it increments at 10, 11, 12, 13, 14, and 15 volts. Do I just remove the preset voltages and input the 10-15volts as per Phearable?

Also, I am getting conflicting info about the 92-96 Prelude VTEC injector sizes, a lot of forum posts say they are 345cc and Phearable and another site say they are 330cc. Is there an authoritative source to find out?

[GeHonda]

I'm not the authority on SManger at all here, but I would suggest reading their documentation about the voltage vs the charts in Phearable. You could extrapolate between the two if you want to leave the SManager voltages alone, or you can adjust and test.

I think about the sizing, within only 4.5% difference between 330 and 345CC I don't think having a definitive answer is critical. The only way to know for sure is to flow test. As flow rates are at a standardized 3 BAR (43.5 PSI), you could bump pressure a few PSI and it would close the gap from 330 to 345 if they were only 330.