240K M50?

[Sanchez]

Knowing the durability of BMW engines and 'bulletproofness' and reliability of them would you buy a 240,000 mile M50B25 thats still in the car, k plate 525i.

It has a full service history with stamps in the book and have been told it runs 'really sweet' by the current owner.

Im looking at it tomorrow in the move for M50ing my E30.

[pac1982]

I went for no if the idea is to drop it right in an E30 with nothing more than a basic service but for the right price i may be tempted to buy it and give it a rebuild or use it as spares

[Brianmoooore]

I have one with that kind of mileage in my E34, and, apart from the vanos seal could do with attention, seems as good as when it left the factory. Doesn't use any appreciable oil, and all the compressions are up to scratch.

[Sanchez]

Its out a E34 and only reason why im thinking about it is the s/h, and good price for the whole car.

Will most likely be a service and drop in the e30 if its running nice, if not get a friend of mine whos rebuilt his M20 to have a look over it.

Will this one be a vanos one? 1992 K plate 525is

[wullie325i]

no it will be a non vanos m50b25

[Brianmoooore]

Will this one be a vanos one? 1992 K plate 525is

Depends on build date, not reg. date, so could be either.
I've a K reg here that has vanos.

[Sanchez]

Cheers Wullie, you still runnign around in Eko's one?

[Sanchez]

how can you tell vanos or non vanos?

[wullie325i]

its in bits at the moment waiting to be painted and then built back up with a m50b28 combo as it ended up sitting around for about 2 years looking sad as i didnt have the time to keep it up to scratch but it should be back on the road some time this year with everything finished 100% this time.

bought a tidy 325i about a month ago to run about in and got about 50 miles out of before the timing belt broke so im back to having no car again arrrrrrgh lol

[wullie325i]

if its vanos it will have a bulge at the front end of the head nearest the radiator as non vanos ones are flat ended

not sure if that makes sense or not but i know what i mean lol

[Sanchez]

Anyone know what else I will need of the E34?

Engine has correct sump so thats a bonus.

does it have that EWS thing?

[wullie325i]

it wont have ews so no worries.

all you need from the e34 is the engine and box if you are using the m50 box that is and the front half of the prop but again theres a few options for what to use here.

[Sanchez]

I was thinking of using the M20 box so prop and diff can stay on the E30, its a 320i.

If not get a M42 box as I have a 'is' prop in the garage.

[wullie325i]

well other than e36 arms and prob some e36 rad pipes ect u should be about ready to roll

[wullie325i]

what are you doing about a fan for the rad?

[Sanchez]

leccy fan i think is what to use.

Ive heard M42 rad is good.
Clio servo/porcshe 944


Manifold and exhaust will be a problem though.

[wullie325i]

im not 100% but i think the diff ratio for the m50 starts around 2.93:1 as when mine is rolling im going for between 2.93 and 3.25 using a m52 box

[wullie325i]

leccy fan i think is what to use.

Ive heard M42 rad is good.
Clio servo/porcshe 944


Manifold and exhaust will be a problem though.

i had a m42 rad in mine for a bit and it did do the job ok but it was a big improvement when i used a e36 m50b25 rad.

clio servo would be my choice and will be replacing the golf servo i have on mine as its very poor imo.

i can do you the manny no probs when the time comes

[wullie325i]

i have a leccy fan from a 7 series and it does the job and fits good aswell.

[Sanchez]

For the manifold, ill have to get someone to do it for me. no welder

Do i modifiy the E34 one then 325i exhaust?




the list below is on the M50/52 swap thread.



M50/52 engine, (budget for doing a water pump change)
E34 sump, oil pickup pipe & dipstick. (new sump gasket regardless)
E36 engine arms
E28 M5 rubber engine mounts
M52 exhaust manifold
Use your own rad & buy the thermo switch which will bolt to the side of the rad
Electric fan - air con fan from E36 or E34 will do fine
Clio servo from 2000 onwards clio
Loom for the electric fan £40 from DanThe
Converted engine loom £100 exchange from DanThe
M20 flywheel & clutch
320 gear selector rod & alloy cradle where the gearstick sits
325 propshaft
Diff - your choice
Coding plug for 6 pot car fitted into your cluster
If your car has ABS then you'll have to use a cone filter
Fit an E36 rack & modify pipes

[wullie325i]

you can use the e34 one but its not pretty to mod and a bit pointless as the m52 tubular one flows much nicer.

i cut the flange on the m52 manny and use 2 stainless pipes on each of the 2 banks one straight down from the manny then one with a bend to get it to sit in the standard e30 position and you can use any e30 zaust u like with no modding to the exhaust itself.

flows well and sounds nice

[Brianmoooore]

If your car has ABS then you'll have to use a cone filter

E34 M30 filter box, with the AFM mounted inside it.

[town325i]

Some of the early M50 5 series had an over drive gearbox

[Sanchez]

Some of the early M50 5 series had an over drive gearbox

Im lost on that, whats over drive?

Yes ill be having losts of help with the swap and from here!!!!!!!

[Sanchez]

what prop and diff if I use the M50 box?

Will I need to change to M20 flywheel and starter motor?

Really need little mods as possible cause im no experienced spanner monkey.

[jbh]

as long as its running sweet and been looked after why not.. you could always do a compression test on it to be on the safe side

[DanThe]

My original M50 had done over 240k by the time I had finished with it, only problem was the valve stem oil seals had started to harden to the point of a little smoke on first startup of the day. Head came off had a clean up/skim/new seals/gaskets/bolts and it was ready to go again

An engine that still runs sweet at over 200k must have been serviced regularly, ive had 60k M52's that were rattly and black with carbon/oil deposits inside due to lack of oil changes

If its at the right price and runs fine buy it, just allow for the possibility of a bit of a head refresh

[Sanchez]

sounds like a goer.

ill report back after veiwing tomorrow.

Cheers for the heads up but ive not finished with your help yet!!!!!!!!!!!!!!!!!

[320ise]

my e34 has done 225k and still runs great its m50 b25 is perfect!

[Brianmoooore]

Im lost on that, whats over drive?

Ordinary E30 gearboxes (and a few very early M50 boxes), have a fourth gear ratio of 1:1 - the input shaft and output shaft are locked together in fourth and all the cogs in the box do absolutely nothing.
Fifth gear on an E30 box is 0.81:1 - the output shaft turns 1.24 times for each turn of the input shaft. I.E. Overdrive.
On the M50 gearboxes fifth gear is 1:1, so to get the same road speed, you need a diff. ratio which is x0.81 lower.
A 3.91 diff on an E30 box would need to be replaced by a 3.167 ratio when connected to a M50 box to get the same gearing.

[Sanchez]

Looks like ill be wanting a M20 box then.

So far this thread has answered my questions, Brian if you need to move it to the M50 part of the forum, or ill start a new thread once E34 is bought.