AustrianVespaGuy

I'm pretty confident in saying the closest setup to what you're describing would be a single DCOE on a Lynx manifold, which is just a great setup IMO, only caveat being air cleaner-to-brake booster clearance: https://www.racetep.com/manufacturer/carbs-and-injection/weber/conversion-kits/bmw-2002-320i-m10-engine-single-sidedraft-dcoe-conversion-kits.html

Even on a 1.8 I don't think you can really go 'wrong' with either a 284 or a 292. From my experience with them, the 284 actually gives you a little more 'meat' in the 2k-4k RPM range, while the 292 makes more power in the higher 5k-7k RPM range. Back when I was rebuilding my engine, new-billet options weren't available, it was NOS Schrick or a regrind. So I went with the 284 mainly because then I could get away with the regrind without worrying about needing lash caps or oversized eccentrics. But if I were doing it TODAY. . . since you can get a new-billet 292 from IE for $300, I'd do just that! On the carb though I'd probably vote 32/36, because while I'm sure the 38/38 will work, I do think that might be a tad big for the 1.8er.

You certainly can't go wrong doing it that way! I do like to try to use existing wiring where possible just to help keep the installation 'cleaner,' but yeah if you're doing fog lights I don't think there's really any shortcuts. Gotta run *some* new wire for the fog light switch itself, and then might as well do it it right with a new relay, battery supply wire, fuse, etc.

Mmm, I'm pretty sure the white wire is always power to the HIGH beams, no low beams. The 'free' white connector is usually for driving lights (higher long throw beams that work together with the wider high beams). If you're putting in fog lights, then those should only be on by themselves or with low beams, and never with high beams. As for this, I would still recommend using that white wire only to drive the coil of a relay, and then run a new good wire from the battery to the relay to carry the actually high current for the light bulbs themselves.

Firstly, sorry for the pseudo thread-jack. . . Hey Jim, finally got around to doing this no-throttle warmup test also, good idea! All in all I'm quite happy with it. There's one little random surge in there that I can't explain, but for an open-loop stepper motor setup I think it's hard to have any complaints! ~1800 RPM for 2 seconds when it first fires, then settles to a cold idle of about 1300, drops down to about 750 when the stepper closes down completely (170deg), then comes back up to 850 fully warmed up (180deg). And ROCK solid AFRs at ~12.6 during cold enrichment and then 13.6 when warm! What a fun log to grab, so thanks again for the idea!

If while bleeding when you press the brake pedal and it goes to the floor, then that fluid is going SOME where. And if it's not coming out of the open bleeders, then it's most likely because there's just more air in the lines that it is still displacing. Could also be leaking out somewhere, so check for dribbles, or *maybe* the fluid movement is being absorbed by the flexible lines, but I think this unlikely, because the pedal would feel a LOT different (firmer) than normal with the bleed valves open.

If they're driving lights as opposed to fog lights, you can always just wire them to come on in conjunction with the high beams and thus you don't need to pass ANY new wires through the firewall. . .

I'm sure it's not a *need* but I'd bet 320i replacements are a whole lot cheaper/easier to find than stock replacements these days, no? And while it's true they're *technically* not serviceable, you're always welcome to give it a try anyway. All you need to do is take a screwdriver to unbend all those little crimp fingers that hold the tank onto the core. Underneath the bottom lip of the tank is a big rectangular gasket. Once you're in there you can try to determine if the leak is in the actual core (small crack where a vertical tube is brazed to the horizontal 'header,' or if it looks like the leak was past that rubber gasket. Then it's just a matter of soldering the hole (if present), making sure the gasket is in good condition, putting it back in its groove, putting the tank back on, and then having something to press it down pretty hard to compress the gasket while you bend the fingers back into place. I'd say probably not worth the effort, but I'd never discourage someone from at least attempting a repair before throwing money at a replacement!

Anyone here on the 2002tii.org site? Seems like it just recently got updated but now all the wiring diagram links are broken. Want to tell them of this but can't seem to find any webmaster link or such. . . Here's the section that used to be my go-to for information that now seems to suddenly be non-functional: https://www.2002tii.org/bmw-02-series-electrical-diagrams/

Since we've necroed this thread and I posted in it originally, I suppose a follow up is in order. I ended up taking out my pod and building a little circuit with two LED bargraphs in it. One is for battery voltage and the other is hooked up to my wideband for AFR:

I've recovered 3 wheels and been happy with how all three of them turned out! Takes a while, a worthwhile job IMO. Even have an extra recovered sport wheel still for sale that strangely no one seems to want, oh well!

This is telling, as the +12V from the green wire should ONLY be there when the key is in the start or run positions, and should be 0V in the accessory position! I suspect you either have some miswiring at the fuse panel or you some crossed wiring somewhere such that your green wire is getting 'polluted' somehow.

Mine's gotta be FINALLY conquering the throttle linkage dilemma that's been aggravating me for YEARS! Wish I'd gotten to drive it a bit more, but I DID make a very memorable 'final drive' for ~2h in March the last day before we settled in for months of lockdown at least! https://www.bmw2002faq.com/articles/technical-articles/engine-and-drivetrain/finally-efi-throttle-linkage-r376/

All of the various air-metering methods rely on exhaust gas feedback for fine-tuning; this is the same across the board for all of them, though the Jetronic AFM system only uses narrow rather than wide-band feedback.

I like this "engineering the installation," good terminology!

Step 1: Have Microsquirt control the original coil directly. Simplest is just having MS use the points opening as its 'trigger,' but then it will control firing the coil directly itself. You can program the entire advance curve yourself to whatever you want it to be, but downside is because of all the mechanical lash from the crank to the points things will still 'wander' by a few degrees. Needs no additional hardware to get going this way though. Still uses the cap/rotor to send the spark to the correct cylinder. Step 2: Ditch dizzy and install a crank trigger and sensor. This gets rid of all that uncertainty from the sprockets, timing chain, cam, gears, and dizzy, and your signal now comes DIRECTLY from the crank. But of course it means adding hardware to front crank pulley. This is generally what you want, though seems to have shown as sold out for quite a while now. . . https://02again.com/?page_id=358 With a crank sensor installed, you can still keep direct control of the single coil, and still use the distributor to 'distribute' the spark. Or you can choose to get fancier and go wasted spark (2 coils) or coil-on-plug (4 coils). I'm a wasted spark guy myself, but we should probably save that whole conversation for a later time after you get things up and running first.

Your plan sounds pretty good but since I've already thrown in my 2 cents on this thread here's another nickel's worth: I wouldn't start with MAF; do either speed-density or Alpha-N first because it's easier/less parts to get up and going, and then do a MAF upgrade once you know your way around the whole EFI thing a bit and can plan it out properly. Ok to start with, but once you've got Microsquirt in and working it's quite trivial to have it control the coil directly. I'd do this (and possibly wasted spark or COP) even before changing to a MAF. Plus if you go this route distributor/petronix/etc. choice will no longer matter as MS will be handling everything. (Chanting: "Wasted Spark! Wasted Spark!") The old flat-top pistons won't get you there but the above coupled with new 9.5 or 10:1 pistons WILL!

Well IE *used* to sell 9.5:1 cast pistons for E12s, so might be worth calling and asking them, however poking around on their website also suggests you can get custom forged pistons from them for only $650 so. . . yeah that's probably what most people looking for new pistons should just do, right? https://www.iemotorsport.com/product/forged-pistons-m10/ As far as this goes, I'll try to break in down in a fairly simple way to make the trade-offs clear. With EFI, the whole idea is to make sure to inject the *right* amount of fuel to properly burn with the amount of oxygen in the combustion chamber. But figuring out exactly how much oxygen is in there is a bit tricky, because even though the VOLUME of the cylinder is constant, the amount of oxygen in that volume changes all over the place with throttle, temperature, elevation, etc. So the various options for how to calculate this are: - AFM - measures how much air volume is flowing past it. But still needs temperature to better calculate the density, doesn't really cover ambient pressure changes due to elevation, and it's pretty far up-stream from the combustion chamber. Oh and it's really just a flapper door in the airstream connected to a potentiometer so correlation between that resistance reading and actual oxygen content is. . . pretty piss poor. - Alpha-N - this just uses the throttle position (from a TPS sensor) to estimate how much air is entering the engine at a given throttle position. So super simple but obviously not very exact either. External temperature and pressure sensors can 'help' refine the calculation, but it's still really just an educated guess. - Speed Density - this uses the air pressure in the intake manifold (MAP = Manifold Absolute Pressure) for the calculation. It's also pretty easy since it just takes one vacuum line going to a pressure sensor, captures pressure changes due to altitude, and is the SAME environment that the cylinders see. But it also still needs temperature data to really finalize the oxygen calculation. - Mass Air Flow - aka MAF, and as the name indicates DIRECTLY measures the MASS of the incoming air. And this is exactly what you want, not 'adjusting' for temperature, pressure, whatever; its just the pure kilograms of oxygen going into the engine, divided by the number of cylinders, and DONE. There is a small drawback though, and that is that the electrical response of a MAF sensor has both a limited range and is very non-linear. This means it does need to be sized properly for the engine (so that the airflow is neither too fast nor too slow to get a good reading), and the engine management system needs to be able to accurately 'understand' the non-linear input response. But get these things right and you understand why all the OEMs do it that way: it directly measures what you need to know for proper fueling!

Ha, shoot, well I guess that makes it all even one step easier! I thought the 320s used the ICVs like the later E30s, my bad! So yeah, if you have the old aux valve with that motor, just keep it for warmup regardless of whatever engine management system you use! Truth spoken here! But for some strange reason, they routinely seem to go for real money, though I can't for the life of me understand why. I think I listed the one out of my E30 locally for $150 and sold it for $120 or something, crazy!

Nice warmup Jim! I'll need to do an untouched log of my warmup sometime to see how it compares! But for the OP or anyone else just dabbling with EFI and not wanting to or having trouble with warmup idle, the super-basic auxiliary air valve from Saabs or VWs work wonderfully. Just a bimetallic spring that warms up and closes off the 'extra' air. Just takes +12V, ground, and 1/2" hoses for the air, no programming required! https://www.napaonline.com/en/p/CRB2799

Challenge accepted! Give me a week or two to work on this one and I'll get back to you with. . . something!

Yeah don't go spending $1k on a pre-build MS3 or something, that's WAYYY overkill. You *could* shave of a little more cost by getting a DIY MS-1 or MS-2 kit, but then you need to solder together the whole board. That's fun for some people (like me), but understandably undesirable for most, and that 20ish hours of your time only saves you like $100, so I think Microsquirt is the way to go. . . unless building the whole thing sounds fun to you! Honestly carbs aren't that bad, and I WOULD say they're simpler than Jet, however the fact is *your* setup already has all the Jet hardware, so switching it back to a carb would mean sourcing a manifold and maybe some coolant and vacuum lines, and so I don't think that'd be worth the effort in this particular case. But don't knock carbs, they really are pretty straightforward and work great!

I'm still going to chime in here with a vote for Microsquirt as the best starting point. Set it up for either speed-density (MAP based) or Alpha-N (TPS based), and basic single-coil ignition control will get you going for $400 (which includes the wiring harness). Then once you figure things out a bit you can spice it up a bit; go MAF if you want or wasted-spark or coil-on-plug or whatever. It's able to do most of whatever you'd want, it then just becomes the question of when and figuring out the plan: https://www.diyautotune.com/product/microsquirt-engine-management-system-w-8-39-wiring-harness/ Hell, an old AFM in good working order will set you back half of that cost right there, won't it? And nothing wrong with Haltech if you'd rather go that route, they certainly are a bit more turn-key, but to me $850 seems on the steep side to dive into unless you're already pretty darn sure that's what you want.

Welcome back! I know you said your old M10 EFI plan didn't work out, but from my point of view your goals are just screaming for some Jenvey 'Heritage' DCOE-looking TBs. . . EFI stuff has gotten a LOT more popular and easier in the past decade so are you SURE you don't want to try for it? For a little more $ you can get some pretty good, almost turn-key systems like Haltech that you can pretty much just install and then go. Bias admission: I'm a big EFI proponent here on the FAQ, so I always tend to vote in favor of it, but I'm also here to help out with such projects! https://store.jenvey.co.uk/throttle-bodies-and-components/throttle-bodies/heritage-dcoe/heritage-twin-tbody-40-48mm-pair-tdp40-48

Gimme your model year and I'll give you a definitive answer. Best guess so far is this '74 connector, but your pic looks much closer to brown/yellow than brown/green. . . I for one DON'T think that's the clock connector, looks more like one of the connectors going up to the fasten seat belt pod IMO. EDIT: Nuts, now I see where you said 1970, but haven't turned up anything like that on my '70 diagram. . . hmm. . bmw2002-usa-early.pdf