Pre-post M20 conversion???

[eko]

Probably been asked a million times before but tryed searching and got no definitive answer so......

I am in the process of buying a pre facelift 320i auto and am going to be converting it to 2.5 manual!
Do i need to find a pre facelift car for a donor or can i get a post facelift and use the running gear etc from that?

Was contemplating an M30 or maybe M50 conversion but cant be arsed to source all the needed parts

[Hyperion]

Hi Eko, i stand corrected but i think you can swap pretty much all the running gear and engine from a Post car to a Pre car.

[eko]

Thanks mate,i know there are a few differences-inj system/water pump(?) etc.

Just need to know if these can be overcome if i buy a post facelift donor!

Basically is it a plug n play swap?

[Ziggy]

It's not quite 'plug & play' in the same way that a post facelift 325i engine into a post faclift 320i would be, but if you get all of the ancillaries, loom, sensors etc, it'll all bolt in fine.

Early 320is used Jetronic, which was different from the Motronic on early 325is, which was again changed for the post facelift 325i & 320i. So if that (Jetronic)'s what the car comes with, it wouldn't be a straight swap even with an early 325i lump. I'm not sure if the 320i ever came with the early Motronic setup, or if it went straight to the later version.

HTH!

[eko]

Thanks Ziggy-so its ok to buy a facelift donor then?

[e21Jason]

Hi


There are a few differences mailny the injection system, & water hoses. Get a later motor with the harness & ecu plus the rad and hoses.

The main issues are splicing the harness plus being an auto you need to change the pedal box plus a bit of wiring from the auto box, as an auto only states when the car is in netural so you need to bypass that.


Jason

[eko]

Thanks guys,thats a big help!

Search will start tomorrow

[Ziggy]

Thanks Ziggy-so its ok to buy a facelift donor then?

If you've got the whole car, anything's possible!

[stevetigger]

So all that hassle and still only a 325i, Why not go for an M50!

Pedal box will be the biggest problem! And Im sure you will need to find the wire that lets an auto only start in P..........If you don't the car will never know what gear it is in and never start!

[Ant]

So all that hassle and still only a 325i, Why not go for an M50!

Probably because the M3 diff needed to use the M50 fully will blow the budget sky high Steve

besides, M50's are not all that IMHO, M52 is an upgrade but the extra valves cost midrange torque on the M50 when compared to the M20, and they have no soul

LE-Jet to motronic is do-able, me, I'd pop an MS ecu on @ the same time, simplifies the process bigtime, all new engine harness to boot and no AFM to just be wrongness.

Good luck M8 !

[stevetigger]

So all that hassle and still only a 325i, Why not go for an M50!

Probably because the M3 diff needed to use the M50 fully will blow the budget sky high



Good luck M8 !

Yer, £50 more than a 325i sport diff!

[Ant]

Yer, £50 more than a 325i sport diff!

true enough but you're assuming Eko wants to change/uprate what he already has

my point is valid, not trying to take anything away from the M50 swoppers, just trying to point out that with the servo swop and the reduced final drive there are EXTRA costs involved in the swop that are not always mentioned up front

I'm going to swop in a Z33.0 diff into mine, if I can find one, 3.64 is to low geared for the torque I have available


anyways enought O/T for now