What shall we do with this M3 engine?

Or: The Roundel sez it only takes 3 days to put an M3 engine in a 
2002.

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It was circumstances that got me here. Just a combination of 
coincidental events. It coulda been different. If the Roundel hadn't 
printed the story saying that it took just 3 days to put an E30M3 
engine in a 2002. If we wouldn't have had an E30M3 engine 
laying around from a parts car. If only son Duncan hadn't read the 
article. If only Duncan hadn't learned to read at all.
Well, I'm sure it's for the best. We're not telling Debbie yet 
that we're putting it into her 2002---we've just told her that we're 
fixing her carburetor leak and putting on a bigger valve cover [all 
true of course]. We won't be able to fool her for long though---
she's much too sharp for that. If it's only a 3-day job, maybe we'll 
be done before she figures it out. Yeah, right. So, here we go.

(She figured it out.)
Old engine out before noon, this is going great. Took off the 
E30 mounts and bolted on the 2002 mounts---sweet. Replaced the 
water pump while the engine was out, removed the fan, removed 
the oil pan for modification, left the headers on, removed the AC 
compressor mount [no AC in this car], and started looking at the 
transmission. 
The Roundel article said that they used a 5-sp from a 320i, 
which is what we already had in this car. That is the trans of choice 
because it has provision for a speedometer drive and the E30M3 
trans does not because modern cars use electronic speedometers. 
But what the Roundel didn't say was that the 320i trans has to be 
modified to allow the M3 crank sensors to be installed in the bell-housing. I shoulda thought of that. So…back to the car to remove the transmission. Next step---put that sucker in!! Hooked up the chain to the M3 engine and picked it up with the A-frame and hoist. Pushed the car underneath with the hood closed, opened the hood and lowered the engine into the engine bay---and right onto the mounts. Just like it belonged there. Wow. Looks great. End of a great day.

Cut out part of a M3 bell-housing and the corresponding part of the 320i 5-sp bell-housing, bolted both parts to an empty M10 block for alignment purposes, and sent the whole mess out to Jim at K&K welding.

Sent the upper part of the M3 oil pan and the lower steel part of a 318 pan to Jim also for narrowing two inches so that it will fit within the 2002 frame rails. A stock 2002 pan will work, and would be simpler, but I like the elegance of the more complex pieces. 

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The steel 318 lower pan is used instead of the aluminum 
M3 lower pan because the oil pan will now be the lowest part of 
the engine, and the steel is much less likely to be broken by 
impact.

    Cleaned up a tii fuel tank, installed it, installed the tii fuel 
sender and fuel pick-up. Mounted the M3 electric fuel pump and 
fuel filter under the car, drilled a hole for the new larger diameter 
fuel suction line, installed one of the M3 high pressure steel lines 
along the left rocker panel under the car and attached the rubber 
connecting hoses from the pump to the steel line and from the steel 
line to the fuel rail at the engine. Ran another hose from the fuel 
pressure regulator to the stock plastic body fuel line to serve as the 
fuel return line [BMW fuel injection systems use continually 
recirculating fuel].

   Trimmed the fan clutch attachment threads at the front of the 
water pump to give a few millimeters more radiator clearance, and 
installed the same 320i radiator we had had in the car before.

End of day 2. Wait just a darn minute. There's still a ton of 
stuff to do. Somebody is slackin' here. Two days are done on a 
three day job---somebody is gonna have to bust butt on day 3.

Installed the modified trans and driveshaft, installed the 
narrowed upper and lower oil pans, and turned the brake booster 
180 degrees to gain a bit of clearance. End of day 3.

End of day 3? Aren't we supposed to be done? Oh, it was a trick. They had 3 or 4 or 5 guys working three days!! That's 10 or 15 man-days, so we're right on schedule.

The rest of the days:
Taking out the 320 radiator and installing the M3 radiator 
and coolant reservoir; making the bracketry to hold them in place. 
Finding coolant hoses to connect engine with radiator and heater. 
Routing wires for the engine harness and the DME control unit. 
Fabricating brackets to install the relay pack and air flow meter.

And, and, and....a thousand other details complicated by our sudden decision to take the car to the European celebration of the 2002.  But we got it done---Brandon Littleton wrapped up the details in time for us to take it to Germany.

So, how does it run? Smooooth and powerful, both on the street and on the track (where it needs BRAKE upgrades). Would we do it again? Maybe not, but I’m glad we did it this time.

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