RC 550 injector tuning
 

setup:
550RC Injectors
FlyinMiata Turbokit ~8psi
Speeduino w/TunerStudio


I had my car running really good with stock injectors (self tune) but they couldn't keep up at the top of the rev limiter, so I went with the RC500 injectors. After installing them and
updating my required fuel to 5.5 I am getting really weird behavior. I got the car running and turned on auto tune and at idle it cranked the fuel cells down to 1/0 and my AFRs are still <10 but under any load they shot up to 200+ and it is still leaning out. below is my setup, any help would be greatly appreciated!


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https://cimg1.ibsrv.net/gimg/www.mia...04998e4f36.png
https://cimg2.ibsrv.net/gimg/www.mia...dac8dc9ae3.png
https://cimg5.ibsrv.net/gimg/www.mia...8fa92e6578.png
https://cimg6.ibsrv.net/gimg/www.mia...5da041d596.png

What really scares me, is your spark table...

Something is way off here, dead times should play a big role, but just send us your msq, thats super sketchy

I attached it below, also here is the link to drive: https://drive.google.com/drive/folde...0o?usp=sharing

Your VE Table is fucked. Recommend reverting to the basemap table, you shouldn't need a 1 at idle, that's insane. If its still reading full rich at idle with a 1 there regardless of the req fuel and deadtime I would suspect the wideband ain't reporting the truth

https://cimg1.ibsrv.net/gimg/www.mia...de1776da29.png

That's The weird part. On the old injectors the ve table was normal and the afrs were good. Auto tune did this ☝️ when trying to get those injectors to play along. I can reset this table, but it's just going to adjust it back again I believe

Curious, new or used injectors? If used, have these been cleaned and/or tested?

Used from a guy Antoine Norman (Uptown Twizz) out of PA. He says they got flow tested before he sold them to me but could be blowing smoke. Just to be sure, polarity doesn't matter on them right? I was consistent on wiring in the new pig tails, but I could have done them all backwards.

Where do I go to get them flow tested?

Is having my Required Fuel at 5.5 seem right? (compared to others running a similar setup)

What are dead times and how do I set them?
EDIT: found this post: https://www.miataturbo.net/ecus-tuni...ad-time-56061/

You can find a local source to clean and flowtest injectors. A popular website is FuelInjectorClinic. The issue is... It's $25 per injector which adds up quite a bit. Rather than clean, I'd just buy new ones from somewhere like GoFlowForce.com
https://fuelinjectorclinic.com/

Regarding injectors, they are injector specfic so the ones you find for lets say RX7 injectors are different from what you'll find for RC550. I found this table which included rc550 in the table.
http://www.phearable.net/information...ead-times.html

Regarding where the setting is located, i'm not sure as i don't use TunerStudio. MS is pretty popular so i'm sure you can find documentation online.

To add, i'd fix the deadtime settings before spending any money. Wrong dead time settings can result in bad idling. Also, autotune shouldn't be tuning 'idling' cells.

Throw the rc550's into the trash where they belong. Get a set of proper injectors. I got your PM, will respond when I get a moment.

Would have been good to know before I spent $$ and cut up my harness :inout:

I have spent a lot more time with the car, trying to get something to work.

https://cimg2.ibsrv.net/gimg/www.mia...8094194fb0.png
There are a few things that I can't figure out here:

1. At idle my AFR's sit just above 10:1 no matter if my VE's are at 1 or at 9.
2. It seems to be scaling way to drastically. at idle I'm at 9 and not too much above that I am already up to 50
3. As soon as I dip into boost it is a losing battle. You can see I have it cranked up to 110 and that is still leaning out past my gauge can read.

My fuel constant is set at 6.5. I believe if I crank that number up a little it will fix #2. but it also makes #1 worse. Nothing I do seems to help #3, as soon as I go into boost the engine leans out hard.

Any insight here would be great. I am also looking for someone that could do remote tuning, there aren't any shops or dyno's where I'm at (So. Utah)

log from last drive

One quick question, have you started from scratch?

A few things:
1) Don't drive around with such a shitty VE table / advance table. Seriously.
2) Update your speeduino, you're on quite an old version.
3) Do a full reset and then try again.

If after all of this you still can't get it right, you probably just have shitty injectors.

1) Is the advance table not good?
2) Thanks for this, I didn't even realize it was a thing
3) I ended up just buying some Flow Force 640CC injectors last night. Once I get those and wire them up ill be able to give this another go

RX7 injectors have a tendency to flood the rotary engine, once turned off, and lead to a two hour wait before you can restart the rotary. Not all sets, but many sets.
I have always assumed this must be happening because they leak.
Perhaps you have one of those sets.

Very good decision

UPDATE: I bought FF460 injectors, got them installed and now I am running into some other weird behaviors. The AFR's spike like it will idle fine for a minute, slowly rev higher, and then drop and the AFR's will go out of range. The other weird thing is when I remove the IAT sensor it gets a lot better. I have checked for leaks by spraying starter fluid on all the injectors and the sensor while running, with no noticeable revving. Any ideas??

It sounds like you have a hunting idle. I installed new injectors recently, and as I am tuning it up I occasionally get a set of values that cause a hunting idle.

If you are using closed loop idle control, look at the idle VE table and idle timing table and smooth them out, so that the idle point is a local minimum, instead of on a sadgle point. Also, watch the VE idle table as it hunts, to see which cells it is going to, and how it gets out of control.

If you are not, then the same advice applies to VE table 1.