RX-8 injector fitment question
I managed to properly crush the head to injectors seals before I realised.
Greg - I’m sorry I don’t know the dead time for this injector. Average for this type of Denso and with 450cc/min is .65ms at 14 volts.*
I sure wish someone would figure this out, I've been looking on and off for a while... I'm running the ms default of 1.0ms and I'm pretty sure its not quite right... idk which way though. Need to just man up and hook up my ghetto flow bench and measure it.
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I was looking at this photo and I saw the injector on the right as listed as a Miata injector. I have never seen one that looks like that. My stock injectors look like this:

Which is why I said they look identical to the yellow RX8 injector. I was thinking if I swapped my red ones for the RX8 yellows, all I'd have to adjust would be required fuel?

Which is why I said they look identical to the yellow RX8 injector. I was thinking if I swapped my red ones for the RX8 yellows, all I'd have to adjust would be required fuel?
I was looking at this photo and I saw the injector on the right as listed as a Miata injector. I have never seen one that looks like that. My stock injectors look like this:
Attachment 20975
Which is why I said they look identical to the yellow RX8 injector. I was thinking if I swapped my red ones for the RX8 yellows, all I'd have to adjust would be required fuel?
Attachment 20975
Which is why I said they look identical to the yellow RX8 injector. I was thinking if I swapped my red ones for the RX8 yellows, all I'd have to adjust would be required fuel?
Either way though they're more or less PnP, just be careful to not tighten the rail down too hard, as I say the RX7 injectors are slightly longer than stock and you risk causing vac leaks by over-crushing the head-injector seals. BTDT
Yeah you adjust req_fuel and then put in the correct deadtime.
Greg - I’m sorry I don’t know the dead time for this injector. Average for this type of Denso and with 450cc/min is .65ms at 14 volts.*
You can work out the deadtime by switching between 2 squirts and 4 in MS and adjusting the deadtime until the AFR's match between the two settings.
I keep meaning to do this with the RX8 injectors but never get around to it.
greg has seq. fuel, he cant do that. Jasonc SBB's method seems to work well. takes about 2 minutes and recording a log.
simply log idle on a warm motor. start increasing the deadtime value slowly until you reach like 11:1.
stop log, plot PW against MAP/AFR. The Y intersect is the deadtime.
simply log idle on a warm motor. start increasing the deadtime value slowly until you reach like 11:1.
stop log, plot PW against MAP/AFR. The Y intersect is the deadtime.
greg has seq. fuel, he cant do that. Jasonc SBB's method seems to work well. takes about 2 minutes and recording a log.
simply log idle on a warm motor. start increasing the deadtime value slowly until you reach like 11:1.
stop log, plot PW against MAP/AFR. The Y intersect is the deadtime.
simply log idle on a warm motor. start increasing the deadtime value slowly until you reach like 11:1.
stop log, plot PW against MAP/AFR. The Y intersect is the deadtime.

Will try the method Jason described. My deadtime is set to 1.2, do I log values both above and below this value? In what increments?
I went ahead and changed my car to that and retuned, haven't been able to drive it enough to really tell if it made a positive improvement or not though. I was running the default 1.0ms setting before.
. I Just measured them side by side with the stock 265cc's using a Vernier gauge: exactly the same length!
greg has seq. fuel, he cant do that. Jasonc SBB's method seems to work well. takes about 2 minutes and recording a log.
simply log idle on a warm motor. start increasing the deadtime value slowly until you reach like 11:1.
stop log, plot PW against MAP/AFR. The Y intersect is the deadtime.
simply log idle on a warm motor. start increasing the deadtime value slowly until you reach like 11:1.
stop log, plot PW against MAP/AFR. The Y intersect is the deadtime.
Jean changed the code a while back so you can revert to batch without changing your wiring, just turn off the additional drivers and you can do the switching thing.
You can do the same thing with your MS3 too.
Hi All,
What injector lag/voltage correction are you using for the RX-8 yellow injector. I am using the standard ms3 correction curve and it is over correcting. (Too much fuel at lower voltage. i.e. when fans kick in).
Thanks.
-Raj
What injector lag/voltage correction are you using for the RX-8 yellow injector. I am using the standard ms3 correction curve and it is over correcting. (Too much fuel at lower voltage. i.e. when fans kick in).
Thanks.
-Raj
unplug your alternator while idling and correct as the battery drains out.
Really, you cab just move a datapoint on the curve to where the voltage drops when the fans and/or a/c kicks in, then just tune to maintain the AFRs. The default curve is very aggresive.
Really, you cab just move a datapoint on the curve to where the voltage drops when the fans and/or a/c kicks in, then just tune to maintain the AFRs. The default curve is very aggresive.
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