Build Thread?
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So the other day I did some serious research and adjusted my coil dwell times and injector dwell times based on other values and calculations.
After doing this I got a knock on one cylinder with a high idle (1300rpm) the knock was fairly consistent but only on ONE cylinder. I tested it with more advance (~15 degrees) and less advance (~8 degrees) with no real change, noting that it would always backfire after it knocked. After some talking with Snap I (we) decided to grab a new set of injectors that I could get all of the specs on (including voltage correction tables) so I listed the old set (Delphi 65lb/hr Low-Z) on r3v and 2 hours later they were sold for just a bit less than what I paid for them. I find it amusing that I sold something that was literally still in my car and full of fuel, but maybe that's just me.
I just ordered a new set of Siemens Deka 80lb/hr High-Z injectors, the high impedance allows me to eliminate my resistor board that I had to run with the low-z injectors so I will be able to simplify my install a bit. It may seem a bit irrational to order new injectors, but it was honestly something I had been debating doing for quite some time now (before the car even ran) to eliminate any possible issues with the low-z and not being able to directly drive them.
If the new injectors still cause the same issue I will start attacking the spark side of things, I will make this car run correctly!
Stock picture of the injectors because posts without pictures suck.
Also a picture of the car with the hood set on, which will fit with the turbo in there, so that's cool!

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I would love to think so!
I would also like to think it will be on 16psi at that point!
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A very shaky clip of Tim's car with the built S52 doing a little 2-3-little bit of 4th pull. Rev limiter is set at 7000 or 7100 rpms right now, and will probably go up still. As noted before it screams, and unfortunately its just not the same in videos...
Did some more investigating today as to why I was getting a single cylinder misfire, got my new injectors in and rewired the ECU for it. Fired it up and still had the same exact problem, so the injectors themselves were not the issue. Started firing coils in megasquirt (test mode) to see if any of them were not firing. Everything sounded in order so I started pulling plugs to figure out what cylinder it was. I think I found it... cylinder 4 is on the right and cylinder 3 is on the left.
Picture was taken right after I pulled them out, and the only one that was different was cylinder #4. After talking to Mr. Snap he suggested to check the ground for the injectors, sure enough it was hanging on by one tiny strand of copper. Going to replace that and see if it helps!
It now makes sense as to why I was making no power, I was never firing correctly on one cylinder. Hope it didn't damage anything!
Video of it running with the knock -
You know whats amazing? The video I posted of my car earlier was it running with the wrong firing order...
I finally found that you do not wire Injector A to Cylinder one, and Injector B to Cylinder 2 and so on. I remember earlier this year finding that the cylinders were all assigned to odd letters, well what I didn't remember was the fact that for the firing order 1-5-3-6-2-4 (upper numbers are firing order, lower letters are correct cylinder assignments for MS3) I had it as 1-5-3-6-2-4
A-B-C-D-E-F A-E-C-F-B-D
so it was missing bad. This explains a lot, like the lack of power. I am quite amazed it ran as it was..
Feel like kind of an idiot, but gotta learn some how. I tend to second guess myself, and this is living proof.
Now I can start making some real forward progress.
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Hell yeah! I got caught up on the same thing with my Miata at some point.
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I got to drive my own car for the first time in 2 years, feels good bro.
It's amazing what a difference the correct firing order makes....
Tuning started, and I have it okay up to about 5900rpm.
No video, but it does move pretty good at 6psi... -
Added more timing, and more power came with it!
I hope I am not destroying my clutch lol , breaking it in easy is not an option!
Sent from my XT907 using Tapatalk 2
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So from yesterdays conversation.
There are two places where intake temps can cause a lean condition which may affect your idle. It probably isnt the reason your idle is hunting but its something to be aware of

^^This one mostly depends on the type of temp. sensor you have, or you can use it to manipulate the signal to make things work how you want them to while disregarding its actual purpose (a last resort on some builds where heatsoaked sensors are unavoidable)

^^ This theoretically should stay at 100%, I have mine set to 70 and it works quite nicely. If i drove my car all 4 seasons then I would want it set to 100 but my intake temperature range only varies between 60 to 100 during the year (rather than -15 to 100)
I believe low-Z injectors are supposed to provide better idle characteristics when using large injectors. Id try refining the idle portion of the VE table a little more.
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I will look into the MAT correction, when it revs up on idle it cuts fuel and hits a 22.4 AFR and then drops back down and does it again.
I am running High-Z injectors now, and boy are they big.... I know the VE Table is all relevant to Req Fuel but my Req Fuel is 3.3 and my idle values in the VE table are around 30, I think I have enough overhead for more power...
I am trying to get it on the road as much as possible to get the tuning knocked out to hopefully make it to a meet!Side note, my stealthy-ness didn't work. The car is loud, the turbo is amazingly loud, and so is the BOV. Went past Jason's (forum browser, Dinan M5) house yesterday and let it spool up a bit, he mentioned that I could have left my intercooler black because "I'm not fooling anybody". Oh well. Always room for a muffler if I feel the need.
Snap: What IAT sensor are you using?
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As am I, I shall try the ~70% trick
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