Just for anyone out there who might care, I jotted down what I spent on my M50 swap into the 318 rally car (previously swapped to M42). I'm sure I missed a few things on both ends (bought and sold) but should be pretty close.
It started with a $400 e34 525i (automatic). Car overall was a piece of junk, but only 160k miles on it and the engine sounded good. As little of a market as there is for e34 stuff, still managed to sell some stuff of of it after pulling the engine, wiring harness, and a few other things:
e34 bought:
$400
e34 sold:
$100 wheels
$150 bumpers, various electrical parts, and a few other things
$150 scrapyard for the car's shell
M50 swap bought:
$60 – ebay headers
$50 – Porsche brake booster
$620 – parts to refresh engine + transmission (mostly from FCP Euro and Rockauto). I replaced basically every seal, hose, fitting, gasket, water pump, thermostat, spark plugs/coil boots, belts/pulleys/tensioners) etc etc. Basically everything on the engine that is a wear/age item other than bearings and head gasket. This also includes fluids, new bolts/studs for the header. I did NOT do head gasket or bottom end.
$110 – e36 parts (driveshaft, motor mount arms, shift linkage, PS pump and pressure line)
$120 - new high-output alternator (rally cars use a ton of power for lighting, electronics, etc)
$35 – AEM intake (ebay)
$80 – new electric fan (pusher)
$270 – muffler, cat, exhaust materials
$100 – miscellaneous parts, coolant hoses, and supplies (est.)
M42 stuff sold:
$400 – M42 engine + Conforti Chip DME
$150 – alternator, PS pump, motor mounts, other stuff
$75 – SPAL hi-perf fan
$50 – SPAL slimline fan
$125 – various e34 parts
$90 – 318 driveshaft + new CSB
$45 – other misc. parts
(will probably sell another $100 worth of stuff)
Re-used stuff that was already in the car: G240 transmission, M20 clutch/flywheel, e36 radiator, M20 expansion tank, diffs
Traded stuff: traded the e34 trunk and tail lights to my sponsor (Condor Speed Shop) in exchange for motor mounts, trans mounts, and 3-4 other parts. So call that $200 value.
Also spent $100 on steel for a big new skidplate (made by Red46), but not counting that since my old one would have worked with some modification - and a street car wouldn't have to buy this.
This is a rally car, so reliability is of high concern for me - so I bought new stuff for anything reliability-related, and most of my used parts purchases were things like engine mount arms and driveshafts and whatnot.
Total Net Spent on swap:
Bought: $1840
Sold: $1335
Net: $505.00
Again, this is rounded numbers and may have forgotten some small stuff (like band-aids and Dawn for cleaning greasy stuff), but this gives a general idea of what I spent, for what it's worth.

It started with a $400 e34 525i (automatic). Car overall was a piece of junk, but only 160k miles on it and the engine sounded good. As little of a market as there is for e34 stuff, still managed to sell some stuff of of it after pulling the engine, wiring harness, and a few other things:
e34 bought:
$400
e34 sold:
$100 wheels
$150 bumpers, various electrical parts, and a few other things
$150 scrapyard for the car's shell
M50 swap bought:
$60 – ebay headers
$50 – Porsche brake booster
$620 – parts to refresh engine + transmission (mostly from FCP Euro and Rockauto). I replaced basically every seal, hose, fitting, gasket, water pump, thermostat, spark plugs/coil boots, belts/pulleys/tensioners) etc etc. Basically everything on the engine that is a wear/age item other than bearings and head gasket. This also includes fluids, new bolts/studs for the header. I did NOT do head gasket or bottom end.
$110 – e36 parts (driveshaft, motor mount arms, shift linkage, PS pump and pressure line)
$120 - new high-output alternator (rally cars use a ton of power for lighting, electronics, etc)
$35 – AEM intake (ebay)
$80 – new electric fan (pusher)
$270 – muffler, cat, exhaust materials
$100 – miscellaneous parts, coolant hoses, and supplies (est.)
M42 stuff sold:
$400 – M42 engine + Conforti Chip DME
$150 – alternator, PS pump, motor mounts, other stuff
$75 – SPAL hi-perf fan
$50 – SPAL slimline fan
$125 – various e34 parts
$90 – 318 driveshaft + new CSB
$45 – other misc. parts
(will probably sell another $100 worth of stuff)
Re-used stuff that was already in the car: G240 transmission, M20 clutch/flywheel, e36 radiator, M20 expansion tank, diffs
Traded stuff: traded the e34 trunk and tail lights to my sponsor (Condor Speed Shop) in exchange for motor mounts, trans mounts, and 3-4 other parts. So call that $200 value.
Also spent $100 on steel for a big new skidplate (made by Red46), but not counting that since my old one would have worked with some modification - and a street car wouldn't have to buy this.
This is a rally car, so reliability is of high concern for me - so I bought new stuff for anything reliability-related, and most of my used parts purchases were things like engine mount arms and driveshafts and whatnot.
Total Net Spent on swap:
Bought: $1840
Sold: $1335
Net: $505.00
Again, this is rounded numbers and may have forgotten some small stuff (like band-aids and Dawn for cleaning greasy stuff), but this gives a general idea of what I spent, for what it's worth.

