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Old 06-01-2011, 10:48 AM   #21
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Originally Posted by Braineack View Post
they only look shorter by about 2mm.



the amount the pintle sticks out doesn't matter. What matters is how short they are once they are fit into the head/manifold.

it looks like the edge the insulator sits on is about 2mm off.
Pictures lie, they might look like that, but they're not. They're ever so slightly longer than OEM injectors.

I managed to properly crush the head to injectors seals before I realised.
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Old 06-01-2011, 09:09 PM   #22
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Quote:
Originally Posted by Greg G View Post
So anyone have the dead time for these rx-8 injectors?
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Originally Posted by Braineack View Post
my guess is the 0.8ms range at ~13.5v. See JasonC SBB's how to find injector dead time post.
I asked the eBay seller if he knew the dead time. Posting reply fwiw:

Quote:
Greg - Iím sorry I donít know the dead time for this injector. Average for this type of Denso and with 450cc/min is .65ms at 14 volts.*
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Old 06-02-2011, 01:04 AM   #23
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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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Old 06-02-2011, 01:18 AM   #24
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Originally Posted by guestlive85 View Post
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:
RX-8 injector fitment question-99inject.jpg
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?
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Old 06-02-2011, 04:52 AM   #25
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Originally Posted by thirdgen View Post
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?
It's a MK1 injector, MK2's are plastic bodied like the RX8's.

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.

Quote:
Greg - Iím sorry I donít know the dead time for this injector. Average for this type of Denso and with 450cc/min is .65ms at 14 volts.*
Sounds a bit short to be honest, I'd be wary over using that.

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.
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Old 06-02-2011, 04:56 AM   #26
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Yep, it does seem too optimistic.
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Old 06-02-2011, 09:21 AM   #27
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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.
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Old 06-02-2011, 11:16 AM   #28
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Originally Posted by Braineack View Post
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.
I can't do the switchy thing? Good thing you mentioned it, I was planning to try it out!

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?
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Old 06-02-2011, 11:22 AM   #29
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just increse it, if you reduce the deadtime too low and start missing and oscillating due to running lean, it can screw up the data.
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Old 06-19-2011, 01:00 PM   #30
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Originally Posted by ianferrell View Post
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.
So... I measured one of my injectors yesterday. At 13.3 volts I came up with .490ms dead time for rx8 yellows. Seems low, but I double checked and had enough precision that I'm reasonably confident that's the ball park anyway. I can explain my testing setup if anyone is interested. I also tried to measure at about 14 volts and got almost exactly the same numbers, so idk.

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.
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Old 06-21-2011, 04:07 AM   #31
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Originally Posted by richyvrlimited View Post
Pictures lie, they might look like that, but they're not. They're ever so slightly longer than OEM injectors.

I managed to properly crush the head to injectors seals before I realised.
Misinformation. I Just measured them side by side with the stock 265cc's using a Vernier gauge: exactly the same length!
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Old 06-21-2011, 04:16 AM   #32
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Quote:
Originally Posted by Braineack View Post
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.
So do I. You CAN do the switching thing.

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.
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Old 07-11-2011, 02:30 PM   #33
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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
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Old 07-11-2011, 02:50 PM   #34
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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.
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