bigcitrus

Yeah, they've done a couple of the "no cutting" conversions now. They know me and my car well (for better or worse!)--it was actually Tom who forwarded me this post in the first place. 

The M20 really does have a lot going for it. Between power, torque, sound, and cost, it's a really nice combo. 

Hi Justin--My '76 has an M20. It's VIN 2374542, only a few hundred away from yours. One of the main motivations for the smog was in fact CA smog...It's fully BAR certified and I can smog it like a normal(ish) person. I realize you're thinking about swapping the '72, but just in case you want to do two at once....

If you want to stay with the "usual" BMW swaps, I think it's a great choice. The S14 isn't affordable or cost effective anymore IMO, and to me the six is a little sexier overall than an M42. If you want to go outside the BMW realm, there's some interesting Japanese stuff (SR20DET, Honda F20/F22, etc). 

The main M20 challenges are:

1. Figuring out what to do with the radiator support. Most M20 swaps have a cut support for radiator and Motronic distributor clearance. Mine was done by Sean and Tom at Casey Motorsports in Petaluma without cutting the support, which involves relocating the distributor, running an electric water pump, and modifying some of the M20 coolant fittings. The core support is a structural piece, so if you do decide to cut it for clearance you'll want to make sure that the front end is properly braced. 

2. Sourcing the transmission. The best trans for the swap is a Getrag 245 from an E21 323i, because it has a smaller case than the E30 unit and a mechanical speedo drive.

Beyond that, I used the 2002 Haus swap subframe, which places the engine nicely. The stock 325i oil pan is aluminum and winds up hanging slightly below the subframe, so that's a thing to be aware of, but that and the radiator support stuff is really the only fitment issues to worry about. It looks like it belongs there. 

Casey Motorsports can answer really nitty-gritty questions about wiring etc. As far as the driving experience, I have few complaints. When I was contemplating my swap, I drove a friend's swapped car and it was pretty much a no-brainer.

Yeah, Roger's Tii also listed it as available--but they're NLA from BMW, so it's a matter of whether or not someone still has one sitting on the shelf. Which, as of right now, Roger, Blunt, and Maximilian all do not. 

Good info, thanks. I'll reinstall the originals and focus my attention elsewhere. 

Right, yeah, I realize my other problems likely aren't linked to the cable, I just was advised to pop in a new one while the box was out and apart.

So I need to pull my heater box to deal with some issues (flappy-clangy noises probably due to missing felt, defrost/heat control stuck), and I was advised by a friend to replace the double/Bowden/temp control cable (64 11 1 351 484) while I'm in there. But, all of the normal places (Rogerstii, Maximilian, Blunttech, dealer) are coming up NLA. Anyone know of a NOS stash? 

Mine is (currently) intact so it's not critical, but I guess it's one of those while-you're-in-there things. On the subject of that...anything else I should do while I'm in there? My fan and everything else besides the two above issues seem fine, for now....