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Nismo Injector time across voltages

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Hi, so i have been looking to find the injector lag time for the Nismo 555cc injectors at various voltages.

The part number is 16600-RR543.

I know the time at 14v is 0.71ms...

Since i have a Caltech Platinum pro i want to know what the injector latency is across the full range...8v to 16v for example.

Does any know this? I have emailed Nismo in Japan twice now with no response :(

my injector guy tells me they are the same as HKS part number HKS 1402-RN008

here is a chart, its at the top of the chart i think.

Attached Files

Hi 13bjunkie, thanks for the reply and document. i do appreciate that. from that i know, HKS modify their injectors from JECS, Tomie and Nismo do not.

Tomie state that their 555cc injectors have a lag of 0.71 sec as stated here: http://www.tomeiusa.com/_2003web-catalogue/e134_fuel_injector.html

...and from what i have researched this is at 14v, so its very different to the HKS.

Crappy. Seems to be a tough information to find.

You could do it the hard way and get it close. Could you not set an afr at a stable rpm, and then induce electrical load and correct the dead time table until you see some sort of a slope? Ive done that in the past with good results. Basically, if your AFR is set at one particular electrical load, it should be the same across all of the electrical loads at that same point. Maybe Andre can chime in with some tricks!

There is a post on a forums from a couple of years back:

http://www.dsmtuners.com/threads/injector-dead-times-getting-them-right-instead-of-using-other-peoples-numbers.418584/

It describes the procedure on how to set up your own dead time table if you can't find one. I've had good results with this technique, although I got lazy and now try to only use injectors that come with all data :)

I'm sorry to say that there are no easy tricks to find deadtime values for an unknown injector. You can adjust the deadtime values at idle while adjusting the electrical load to maintain a stable AFR however all this does is ensure that difference in deadtime between one voltage site and the next is correct - It doesn't give you accurate deadtime values.

The best advice is to buy injectors that are correctly characterised from the start and use this data - Short of finding a company to characterise your own injectors this is really the only way I know of.

Here's the thing though. 20 years ago most ECUs didn't account for deadtime. 10 years ago 90% of tuners didn't know what injector deadtime was - Even now many don't. Regardless of this we still managed to tune engines and get acceptable results. Properly accounting for injector deadtime is going to give you a more stable and consistent tune, particularly as battery voltage fluctuates, but it also isn't the end of the world.

For the best results, buy and use injectors with known data that you can enter into your ECU and be happy. Without this your likely to be just guessing and the default deadtime table in the ECU is probably as good as any data you're likely to find on the internet. It won't be correct but there's a pretty good chance it will be better than having a deadtime table filled with zeros.