autos need a load more wire chopping out of the engine loom but its not too bad, you have to disable the automatic car setting in the ecu too.
you'll have the power to weight ratio of an e36 m3, trust me 323i brakes wont do it. AS far as which brakes to go for there's a number of options but they all involve a bit of fabrication work..
The 323i brakes are exactly the same as the 316 only vented at the front, i couldnt tell if there was any difference when i changed the rears from drums to disks. I did notice a massive difference running wilwoods though.
But i dont think they were powerful enough, so now i am going to be running 300mm two piece floating disks with massive AP four pot calipers on my track car, also will be upgrading the rear brakes to two piece.
Wiring is pretty simple you dont really need to do much to get the engine running, besides running your sensors and starter signal, power and grounds, the engine loom is pretty self contained and takes care of the rest.
So to recap
Engine -
You need an m52b28 minimum, the fact the block is alloy so vastly improves how the car will handle if you used something like an m50, the below applies to using an s5x block and hopefully the weight wont be too much as the front wheels will be in the air anyway
Get an e34 m50 sump - big scene tax on these now so by the time you have finished you will have blown about £400 quid on just this bit.
Brakes
If you are keeping the standard brake servo system - you can use m20 mounts and an m20 box
sump will be a couple of inch off the ground - you will need to mark it, cut it and - reweld it with wings on the side to keep the capacity up, and also a baffle put in.
Cooling
Rad - electric cooling fan and get one that fits it into the aparture to ease clearence if you ever need to change a belt you wont have to take the rad out - i had a custom one made for this reason.
Wiring stuff
Easiest bit of the conversion really,
connecting the engine to the car wiring is simple - you dont need to keep the x25 plug, you can cut that off and solder the original e21 plug - do take out as many wires from the original engine loom as best as you can - there is a carrier bag of redundant wire in there
ECU - needs Abs rev cut eliminating, ews, and if car is from an auto needs to be switched to manual. or convert the engine to run on obd1 and get it mapped.
Drivetrain brakes n stuff
Invest time money and effort in a complete brake upgrade, i cannot stress how important that is really, stock brakes are ok for a standard car, but you wont be going slowly with the acceleration that your car will give you - it will easily go off the clock.
Clutch - use the m20 clutch and the flywheel and the center spigot bearing for an m20 engine, if the flywheel is from an e30 then you will need to get the rear of it machined to clear the bottom of the sump - you wont need to change the prop, the m20 stays in the same place but its a good idea to replace the center hanger bearing and the guibo when you do this swap as they will wear out quicker from extra power.
Rear end
Now theres been at least a hundred threads about this,. i have ran a stock rear end with a quaife diff, then an e12 m535i converted rear beam with stock shafts, this time for my track car im going to be using e30 diff center chopped into the middle of an e21 rear beam and custom shafts.
I hope this clears up some stuff,
