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

[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.

[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.

[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.

[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.

[TrentW]

Thankful no emissions testing required for my E30 here in Illinois. You West Coast guys must get awfully frustrated trying to get a passing grade.

Thanks for a thread that's making me eager to start my 2.8 stroker build this Spring.

[KIRIEIW]

It seems a big part of the failed smog checks was that my temp gauge has been going to about 3/4 pretty consistently even when driven fairly normally.

Considering excess NOx is caused by the combustion temp being too hot, that's a good place to start :). I had one hell of a time bleeding the cooling system on a buddies early style cooling system last weekend. The car would start to creep to around 3/4 only at idle after a few minutes. After bleeding the car over the course of a few days, letting it sit over night, try again the next day, ect. it seems I finally got all the air out of the system (fingers crossed anyways, seems to be OK now). I've bled at least 10x e30 cooling systems over the years but this was the first early style cooling system I've dealt with. Not sure if I just got a stubborn one or if early cars are just a bit trickier, but if the temp continues to climb even after replacing those temp sensors you mentioned, its just a thought. Awesome build man keep it up.

[betz]

Hoping some spark plug whisperers can chime in here.

Here are what my 6 spark plugs look like

Cylinder 1 looks different from the others. It appears to be either rich or oil contaminated. Not too sure, nor do I know what it means for me...

[betz]

Headers in (finally)! Ceramic coating took forever.

I'm going with S52 injectors to rule that out and hopefully have more than enough flow. At this point running too rich would be a welcome sight.

Going on snowboarding trip, so probably won't see any more progress until next year.



Beer for scale

[betz]

Custom burnt chip tuned on dyno or Ms pnp....

No idea where I'd find someone who does custom burnt chips on dyno in California.

I have been considering the MS PNP. Dear Santa...

[digger]

Custom burnt chip tuned on dyno or Ms pnp....

[betz]

UHHH another fail. I'm so freaking close dammit! Below's the results of the three tests

It seems a big part of the failed smog checks was that my temp gauge has been going to about 3/4 pretty consistently even when driven fairly normally. I replaced both the thermostat sensors and now the needle stays dead center.

After fixing that, I first I tried putting in the stock ECU (spare 179 ECU w/ E30 chip). It was shaking a ton at idle and super lean at the stock setting. Putting the AFM wheel back at the setting the shop had set it and it was fine. I changed out my AFM for a spare that hasn't been tampered with. Started up the car and it just dies immediately. Elbow for the ICV popped out changing the AFM - no big deal, but that could be the source of a vacuum leak. Pop it back in and it runs totally fine, maybe a little bit of shudder at idle that goes away given any gas. Surprised since the seemingly stock setting of the old AFM it was shuddering like a mofo. Drive it around and it's very slow but I have experienced this before and it's just the ECU doing its learning thing. After driving it a bit it seems perfect. A bit slower than with the Sssquid tune, but that's what I think I would want for smog.





Way I see it, I have three options-
1- Put the ECU with the tune back in, since it will probably deliver more fuel. Although, it will have advanced ignition timing and that could push it over the edge. Will probably do this regardless.
2- Let the shop play with the AFM again, possibly messing up the AFM again but possibly richening it up a bit to pass smog.
3- Use the stock ECU and up the fuel pressure, either with the bavauto or the 944 regulators. Or an in-line screw that some Mercedes have for adjustment, if I can find one. This way the timing is still retarded a bit but there's more fuel at all RPMs.

If anyone else has any other ideas, I'm all ears.

[2mAn]

Failed again... Damn. This time it passed the 15mph but failed the 25 mph even worse.

Going to try plugging in the stock ECU and take it from there.

Ive heard that this is a good reason to go with the Miller MAF setups because you can have a tune specifically for smog and another for performance. Of course its a lot of time on the dyno so its not a cheap solution and then you have to hope that the smog guy doesnt notice that its a MAF conversion

[betz]

Failed again... Damn. This time it passed the 15mph but failed the 25 mph even worse.

Going to try plugging in the stock ECU and take it from there.

[betz]

Make sure you warm up the cats by... spirited.... driving

Yes... to warm up the cat...

[2mAn]

My car was at the shop- it's done now! I was getting the AFM readjusted but also getting the transmission dowels put in so my starter will be better aligned, it was noisy before, now it's nice and quiet.

Apparently I had set it too rich, so the oxygen sensor was overcompensating and leaning it out a ton. Now everything is good, and apparently pulls waay harder above 3k. Am super excited to check it out after work! I might just take it straight to the smog place after.

Make sure you warm up the cats by... spirited.... driving