I recently (about 3 months ago) purchased a 1972 Bavaria 3.0s, 4 speed manual, original owner. Now, the car isn't in the best shape, actually, it has a lot of problems: -Dual carbs way out of tune, runs very rich -Brakes are unreliable -Some minor body rust -Non-Original paint hasn't worn well at all -Hood won't stay opened -Windows don't like to roll up and down (manual windows and locks) -interior is trashed -clutch is worn, but still works well enough -exhaust is leaky/rattly -power steering is dead -overheats on occasion now, there is some good: -newer bilstein HD's all around -Engine was completely rebuilt 10 years ago and has since had about 40k miles put on it. Even though it's running incredibly rich, it always starts right up, and once warm, idles beautifully. In fact, once the engine is nice and warmed up, the engine runs almost silently, perfectly smooth. I guess my biggest question is this: how hard is it to tune the dual zenith carbs on these things? I love the car, and even though it's a mess right now, I get a smile every time I get in it. Any Golden Gate Chapter members willing to lend their expertise are more than welcome to. Photos can be seen here: http://gallery.me.com/derrick.duggins#100008&bgcolor=black&view=grid
I hate tuning the carbs. It is a real PITA. Now, if they are running rich through the range, you will likely need to rebuild them or at least go through all the tuning steps (check that the chokes pull off before doing anything else.) I know that the kits are available from Mobile Tradition, because I just had to rebuild a set for a coupe. Unfortunately, everything else does not sound super promising. Lots of it takes real money to fix unless you are really handy, and even then it takes money for parts (like a radiator, which is the usual cause for overheating on these cars.)
Welcome to the joys of E3 ownership! Seriously, unless the car has led a sheltered life, a lot of what you are describing is very typical. I would recomend that you check out the special interest group http://www.seniorsix.org/ The e-mail list is "interesting" when there are no car topics being discussed, as the typical E3 owner usually isn't representative of the newer BMW owners. But they know E3s.
If you were closer, I'd offer you my Zeniths since anything that gets my Barbarian back on the road will probably involve a 535 drivetrain swap. But I'm in Wisconsin. So I'd consider a couple of alternatives. One is to dump the Zeniths for some other easier-to-work-on carbs. Not real cheap, but at least a dependable end result. Downdrafts would bolt onto your manifold. Side drafts would require a different manifold. A second possibility is what I have in mind. Transplant another M30 in there. One of the most indestructible parts of an E23/24/28/32/34 is the updated M30 engine that bolts in where yours is. One of the best parts is that it is fuel injected and electronically managed. You are near Bill Arnold, who can tell you what stuffing a 3.5 into a Bav physically entails. In relatively stock form (he builds nasty race versions), I can't believe there are too many issues. I'd almost bet you can pull a 3.5 swap off for less than it would cost you to install and tune a good set of Weber side draft carbs.
Uh, it's a rather large step to go from messing with the carbs to doing a full M30 powerplant swap, including the fuel injection. It's been done, but there are significant issues. Bill Arnold's FrankenBav was a masterpiece of later model subframe fabrication into an E3 body shell. It is also for sale if you are interested in a proven winning race car. Not cheap. A pair of Weber 32/36 DGAVs can make life a whole lot simpler. I did my swap in 1981 and never regretted it after trying to get the Zeniths in tune for a couple years. If you are really concerned about the slightly smaller bore of the Webers vs. the Zeniths for the full throttle blasts down the autoban, the 38/38s have also been used, but with a significant decrease in fuel mileage. Of course, the best way to pour raw gas into an M30 is a set of triple sidedraft Weber DCOEs. Really needs a hot cam and free-flowing exhaust to get the full benifit, though.
Actually, the whole drivetrain is a drop in apart from fiddling with the brake booster for certain types of intakes.
This is all good information. As spring warms things up over the next few months, I'll be doing lots of work. Apparently it's nearly useless to try to tune the zeniths. I've been told that by many sources, which is sad, because I'm sure BMW used them for a reason. I think a fuel injection system will be used eventually. Most likely an e12 or early e24 bosch system.
Do not use L-jetronic. Go straight for Motronic. You'll thank me later. If possible, go for the Motronic used on the E32/34.
Precisely why I did not mention the E12 in favor of all the later M30 systems. The latest one is no doubt the best one, but the others may be easier to find. I do know Bill's Bav and I know why it was built. I autocrossed against him at Watkins Glen. Yes, he beat me. I did not know he messed with the subframe and stuff, but I suspect he did it primarily so it wouldn't break in Newfoundland; not because the engine wouldn't fit. AFAIK (deferring to Moosehead here) an M30 is an M30 is an M30. Might require some different engine mounts. Another guy who did a 3.5-into-Bavaria conversion is 'Rev. Al' Taylor, who raced 'The Cowvaria' (painted like a Holstein cow). I later had the radiator out of it in my 535is. Al is in North Carolina, though.
Kinda. The very late ones (late 89-) were missing some critical bits to make them fit older cars. The bell housing does not have all the outer mount holes for the early automatics and the passenger side is missing a very important boss for mounting the engine mount brackets that the old cars had. The earlier ones had the all the bosses but they may or may not be drilled and tapped for bolts (that is no problem, though.) Al is a nutcase. Gotta love the guy, though. He came up to out shop after towing a car with his 524td and loaded it up with some parts after selling us a diff.
Never met him, but drove a car he sold from Raleigh to Milwaukee. Search "635C" in MyE28 for the whole story.
It's too bad I don't really want to ditch the engine in the bav. It's a phenomenal engine. Rebuilt 10 years ago and is still perfectly smooth and silent once warmed up. And POWERFUL. Maybe some good carbs for now and a decent clean-up of the cosmetic stuff. I did an "e2i" conversion on my 1984 528e a few months ago, which entailed sticking a e30 323i head (731 casting) onto my 2.7 long stroke m20 and upgrading to Motronic 1.3. It's produced great results. That said, major engine work is out of the question for now =)
Well, if the engine is good, all you will need is to swap the upper timing cover, cam or nose on cam, balancer, intake, add electronics and you are golden.
I'd echo the Weber 32/36 swap. Kits are out there, and they will make your life MUCH simpler. I first put them on my Bavaria back in 1981 also only later to pull them and switch to 45DCOEs (Korman built motor). The sidedrafts were awesome for performance with the modified motor and all, but they were a pain to sync, and just in general less friendly to live with for a daily driver -- especially if the weather varies a lot in temperature where you live. Stick to the downdraft Weber conversion with a relatively stock motor. If it was me, I'd not put any money into an old E3 unless the overall condition of the car was good-excellent to start with (rare to find an E3 like that). I sold mine back in 1994, and then tried to find it to repurchase a few years ago. Sadly my original family owned, outstanding condition, zero rust Bavaria (with many tasteful mods) which won the Best Bavaria award at the 1982 O'fest was left to rot in a field by the new owner for a few years this decade, so I was in fact very sad to have found it.
