2.8L M20 9.8:1 stroker build: my 323i reincarnated

[betz]

I bled the thing once more with redline water wetter and now I think I'm finally seeing the 80C thermostat do it's thing. It'll usually sit below the halfway mark now. So, I don't think going forward the radiator will be an issue (fingers crossed...) But yeah, I have an early model so it's a bit more complicated and tougher to bleed from what I can tell.


These NOx emissions are proving to be a total bitch, but at least it's telling me that something is wrong. Look at this graphhhhh



What I'm thinking is I'm just slightly on the lean side. Probably somewhere near the "best economy" part of this graph. I finally found something that sort of matches my cyl 1 spark plug, apparently the darker color and glazed look could be a lean condition. Not sure why it would just be that cylinder... maybe the injector is malfunctioning?

No matter, "best economy" were definitely not my goals for this car and I want to get in that big fat red line part of the graph. Side effect, It'll have lower NOx emissions. I have 21.5 lb pink top injectors coming tomorrow. Since there's no possible way higher flow injectors will make it run leaner, I've got nothing to lose here.

Fingers crossed.

[betz]

A full standalone or at least a WB O2 is looking more and more appealing. Pink top injectors have, against all odds, caused it to run even leaner. Somehow though, the emissions are better than usual. Probably because my engine cooling is great now. (BTW just learned 80C is the normal thermostat so now I feel stupid. Oh well. Low temp tstats are mostly hogwash anyways.) The water wetter and re-bleeding caused my needle to stay just below half pretty much no matter what.

So now I'm going to post a neat Excel of all friggin 6 of my smog tests. I honestly don't know what to do next at this point. Maybe another tune from Sssquid. Jay has been very accommodating thus far.

[AWDBOB]

I can only imagine what a pain that must be to get it to pass. In PA, OBD1 emissions get tossed on a dyno as well, but since all of my E30s were AWD they were exempt because they never made an AWD emissions dyno haha. Now everything is registered in Indiana, where there is no inspection or emissions whatsoever and it is wonderful.

Megasquirt may be the way to go. And if you were planning on ITBs, you'll likely need it at some point anyway so it's a bit more justifiable.

Unrelated: how much would you say you spent building your stroker? I have all the parts for the rotating assembly, I just don't want to drain my wallet if it ended up being extremely costly.

[2mAn]

replicate what you had on the 2nd test. M50 injectors, Sssquid chip and adjusted AFM and test it again. It was close, but was running hot. Should be the closest setup, and if I remember right, thats when it was running the best.

[betz]

Ohhh myy goddd

Put a stethoscope up to my injectors. Cyl 3 isn't firing. That would explain why bigger injectors = somehow running leaner. The new injectors effectively turned my car into a Volvo.

In other news, I decided that my ECU was better off thinking my motor was an M30B35 instead of an M20. I put the original chip back in my 179 ECU and put in an M30 AFM. Seems to run better in my Volvo motor but can't really tell for sure with one cylinder pumping air.

[betz]

Holy fuck, I passed the shit out of smog!

[wworm]

Yeeew! Congrats! so the m30 maf and chip did the trick?

[iXguido]

Wow was there anything even coming out of the tail pipe? That’s impressive

[betz]

Yeeew! Congrats! so the m30 maf and chip did the trick?

M30 AFM and I just ran the Sssquid chip'd 173 ECU that I originally ran with. The big difference was the S52 pink top injectors. One of them wasn't firing, I was running on 5 cylinders. Once I replaced that, the thing was running ship shape.

I didn't run the M30 ECU per advice from Jay at Sssquid. The mapping is too wildly different for it to be perfectly safe on an M20. Although in my experience, it seemed to be working just fine. I figured I would just allow my M20 ECU to correct for the M30 AFM and the injectors.

I'm pretty amazed how low the numbers came out though. Like, 2 ppm. Holy shit. I guess it's what I should have expected with a correctly rebuilt motor.

Oh and, the thing feels waaaay faster now. ;D

Next step after transferring the title and whatnot, I'm taking it to a dyno. I'm going to take a few pulls, HP & TQ of course, along with an AFR reading, and get a new tune based on that. Also for the M30 AFM / S52 injectors.

[2mAn]

Nice work!! Can’t wait to see what it does on the dyno

[digger]

175-180whp

where did you get the injectors with the dud one?

[betz]

175-180whp

where did you get the injectors with the dud one?

CAtuned. They did send me another pretty quickly, no charge. Claimed to have just tested them so they were skeptical it wasn't firing.

[zwill23]

Congrats dude! That was a serious battle, time to enjoy your creation ;)

[betz]

Thanks, it definitely wasn't easy!

2018 stickers mothafuckaaaaaaaaYEAH

[mr.]

Ireland Engineering exhaust?