1989 BMW 325i Convertible: A Nice Clean Swap

One of the many paths my automotive life may take in the near- to mid-term involves adding a BMW 325i convertible – 325iC, ‘vert, E30, insert your colloquialism of choice here – to the stable.

It’s the dead of winter in Minnesota, but today the sun came out and the temperature went up to 40F degrees. So of course I started looking for clean, relatively unmolested examples. Shockingly, there aren’t a lot of them on the market right now. At least, not anywhere near here.

I had not been looking at cars with engine swaps. If someone is going to do something silly to my car, I’d like it to be me. But when it became apparent that unmolested cars were thin on the ground, I expanded my search. Seeing this black on mostly tan 1989 325i droptop brought back a flood of memories.

Full disclosure – I worked for Bill Arnold for almost five years, from late 2002 to early 2007. We built all sorts of goofy cars for both street and track. More relevant to this story, we built one of the first S50-swapped E30s in the San Francisco Bay Area, a Diamond Black 1991 318i sedan. By the time we were done it was pushing 300 horsepower to its E30 M3 suspension, brakes and wheels.

Back in the day – yikes, how old am I? – there wasn’t a kit, per se, to drop an E36 M3 motor and transmission into an E30 chassis. Bill sat down with two or three BMW Electrical Troubleshooting Manuals (ETM) and pieced the engine harness together (my colorblindness makes me useless for these chores). We cut down the E28 5 series engine mounts. We fused in a full E30 OBC and cruise control. The only thing lacking was a clutch helper spring; M42-powered E30 318s didn’t have them, and we never converted to a 325i pedal bracket.

Bill used the car as a daily driver, a kid hauler, and as a Car & Driver One Lap of America entrant, as well as driver’s school weapon. Food for thought – that little 318i would outrun an E46 M3 on the front straight at Laguna Seca.

The seller of this convertible lists out the items used in the conversion which gives you an idea of the work involved. It’s not hard, but it is time-consuming to pull all of this together. The wiring, which used to be the most time-intensive aspect, is now easier with kit parts. The rest – even moving the battery to the trunk in place of the “wiggle weight” – is plug and play.

That doesn’t make the effort any less impressive. A clean black 325iC on 15-inch basketweaves is a great look, and this car presents beautifully. The trunk badge appears to be in the correct spot, and for a California car the paint is deep and shiny. The dashboard looks perfect, and I love the 3-spoke M-Tech I steering wheel. I’m sure mechanically it all just works. However, like most personalized cars, a couple of things stand out.

The reupholstered seats are atrocious. The centers look like cheap covers. And while they had the seats apart, they could have at least installed heater pads (the wires and switches are also plug and play). The convertible top has issues. Apparently, and though it’s hard to spot, there’s a dent in the right front fender. A shot of the damage would be nice to determine if paintless dent removal could cure the blemish.

These are easy fixes, but at $13,500 they shouldn’t all be necessary. I can almost see not fixing the top, despite it being maybe just a plastic window replacement, but the dent is a no-brainer. The seats are a matter of opinion. Further, I’d want to know if the heat and air conditioning work; the engine conversion should not have affected their operation.

The seller claims the car was built to be a daily driver. There is absolutely no reason this cannot be true. But maybe just not here in Minnesota.