M20 2.7 or M50 2.8?

[Andy335Touring]

will rule out the 320d gearbox then just looked through a old total bm mag at a 3.2 evo conversion which was done by Zoom motorsport last year, tried web site & tel no. no joy Do they still exist

I don't think they do ?

[jmc330i]

will rule out the 320d gearbox then just looked through a old total bm mag at a 3.2 evo conversion which was done by Zoom motorsport last year, tried web site & tel no. no joy Do they still exist

I don't think they do ?

Pretty sure they went under

[DADDG]

hi all thanks for info on zoommotorsport scoured some articles on tuning m50/52 and found a feature called e36 tuning lesson (june 05 pbmw).Company called Branded untouchable have increased performance fom 192 to 230bhp using 2.5 engine

[DanThe]

How much did it cost and what did they do?

[DADDG]

no price list but they have a web site & tel no. 01246204669 http://www.but.at. This is what they have done:-
Big bore throttle body,carbon fibre induction kit,schrick cams,unichip,tubular exhaust manifolds

[DADDG]

hi tried link to branded untouchable no joy but if anyone wants to read article its in PBMW june 2005 issue.

[ian332isport]

225bhp after the hassle of wiring up vanos etc, pissing about with re maps. for 35bhp more than standard 190bhp from 2.5 non vanos....

Hassle of wiring up Vanos ? What hassle is that then ?

Ian.

[DADDG]

M50 is easier than you think. The way to go is a Ԛ£250 ebay 525i with a decent dry engine, M20 flywheel and clutch and bog standard M40 318i gearbox. This bolts straight onto an M50, costs about Ԛ£30 to buy and because it's an 0.81 overdrive means you don't need a different diff. You can also use a 320i prop, another worthless item. The 318i box is pretty strong and providing you don't kick the living shit out of it will tolerate an M50 okay. The E34 525i radiator also drops straight into an E30 with no mods. I'm sure the 525i downpipe can be mated to an E30 centre box with some deft modding.

The M50 is 192 bhp from the box, 200 bhp with a chip. If you get a J or K plate non vanos unit it's 2 hours max to lift the lid and drop a pair of Schrick cams in for 220 brake - never mind all this M20 drama of removing the head and punching old rocker shafts out. The M20 is just old, old news and when you can buy something so superior for peanuts - why bother? As for oil leaks, I beg to differ - the M20 is a shocking thing for oil leaks, the front cam oil seal being a prime suspect as well as the cam cover and the four rubber half moon seals.

Do it the above way and you could have it in the car running and driving for Ԛ£500. Then so sell all the remaining E34 bits on Ebay to get some of that back. Buy an H plate 525i and you might even be lucky enough to get the early one with the overdrive Getrag 260 box attatched.

A 2.7 has it's place but to get 200 bhp costs a lot of money.

[DADDG]

Might be able to get hold of a 1995 e36 323(2.5) bits , its been accident damaged and engine has already been sold is there anything worth salvaging like wiring loom etc for m50 conversion i may get bits for maybe the price of a pint not sure if gearbox is available but i'm assuming its no different

[jmc330i]

225bhp after the hassle of wiring up vanos etc, pissing about with re maps. for 35bhp more than standard 190bhp from 2.5 non vanos....

Hassle of wiring up Vanos ? What hassle is that then ?

Ian.

I thought that. Maybe he means the EWS on the 2.8s, but even that isnt much hassle

[DADDG]

Whats the difference between a wiring loom from a 325i e36 saloon 1995 and a m52 2.8 engined e36

[DanThe]

Im pretty sure all the 2.8 M52's have EWS

[jmc330i]

The 328i's have EWS as will any E36 from Jan '95. Most E36 325i's will not have EWS, but there is a chance that the very last of the line M plate 325i's will.

There is probably also some wire colour differences between the two, but the major one will be the EWS wiring.

[DADDG]

cheers for that looked at one of the us e30 sites and one of the guys has done a step by step write up here it is if anyones interested

Here is the write up, everything you need, good luck.

First I would like to give a word of advise to anyone
doing this swap. If your main goal is making your E30
fast, do not do a 2.5L swap.
Trust me you will be disappointed. In my opinion the
smallest engine you should put in your E30 is a 2.8L
M52. The simplest and probably most economical engine to
swap is a 3.0L S50 engine out of a 95 M3 primarily
because it already comes with most of the OBD I hardware
you will need for the swap.
The only problem with 95 S50 motors is that they are
becoming old and it is very hard to find one in good low
mileage condition for a reasonable price. You might want
to consider an option of building a high compression
2.8L engine that will perform on par with a 3.0L and
cost less. One good way of building a low budget high
performance 2.8L is purchasing a 2.5L M50 engine out of
a 525I (so you can get your oil pan) and stroking it.
There are plenty of 2.8L core engines out there for as
little as $200. One trick of making it high compression
is reusing the 2.5L pistons (only if in great condition
with new rings) with 2.8L rods and 2.8L crank. The
combination will give you a compression ratio of around
11.25:1 according to my estimates. With M3 cams (ether
3.0L or 3.2L) the engine dynos at around 240-250
crankshaft horsepower with stock injectors. Upgrading
injectors would probably make even more power because
the engine leans out and stops making power after 6200
rpm. One downside to this high compression is you have
to use the best gas money can buy. Sometimes in hot
weather the engine will ping even on a 91 gas so if 92
or higher octane gas is not available in your state you
probably shouldn't consider this option.
Things that need to be modified:
Brake Booster: Use an E21 320I brake booster. Some
people use 325IX brake boosters but 320I boosters are
cheaper and allow you to use your stock master cylinder.


Note how the fins are ground down to clear the brake
booster.To make the 320I brake booster work in your E30
you will need to cut the shaft off to the same length as
your E30 booster, grind it down to the same thickness
and thread it with a 10X1.5mm dye.
Be careful here, if you screw it up you will need to go
out and get another booster, the shafts are non
replaceable. Don't forget to grind off some of the fins
on the back of the intake manifold to clear the brake
booster.

Transmission: There is a bunch of different
transmissions you can use in this swap. Some people keep
their E30 Getrag 260s but it requires fabricating a
custom transmission mount and your shifter will be
offset to the right by about 15-degrees. My favorite
transmission to use is S5D320Z out of a 95M3, 96-00 328
E36 E46, 96-99 M3. The reason I like them best is
probably the fact that you c+9+an use a 135mm guibo on
them and they are rated for 320hp, which should give you
plenty of room if you are planning future modifications.
S5D320Z transmissions are not the lightest but they are
the strongest. You can use your stock 325 or 91 318I IS
transmission mount with any E36 transmission. Don't
forget to use E21 320I transmission mounts (they are
stronger then e30 or E36 mounts) and weld two cups to
the transmission mount to prevent the engine and tranny
from moving around too much and hitting the radiator
(see pic).

Transmission Mount Reinforcement. The shifter arm has to
be out of an E36 328 or M3 along with the aluminum arm
that connects to the top of the tranny.

Drive shaft: If you are using a ZF S5D320Z transmission
you will have to use a drive shaft out of an E30 M3, 98
M3 (U-joint type only), 87-88 325E or 96-98 E36 328. Use
the E30 center support mounted backwards on E36 drive
shafts.

Clutch: The ultimate clutch is of course E36 M3 but some
people on the budget use an E36 328 clutch (it is the
same diameter as M3 clutch). Those who use a 328 clutch
can also use a flywheel out of an E46 323I or a 2.8L Z3.
It is virtually identical to a 328 flywheel but lighter.

Firewall: Cut some of the insulation off the heater
blower motor cover. Some people strip it completely but
I take a long knife, put it parallel to the firewall and
remove some material.
Do not get rid of the rubber drain on the passenger side
of the firewall that drains the water from the wiper
motor compartment or you will end up with water in your
spark plug holes every time you wash the car. Bend the
heater pipes towards the driver's side of the car and
down about an inch to clear the intake manifold.
Engine mounting: The engine can be installed completely
assembled with all accessories except the front harmonic
balancer, A/C bracket or A/C compressor.
I prefer to install the engines completely stripped
since it makes it easier to connect the heater hoses .

For the aluminum mounts you have to use the E36 arms.
The rubber mounts are out of an E24 E28 (part number 11
81 1 132 793). The mounts have to be mounted in the
outside mounding holes of the sub frame.

Note the aluminum spacer under the engine mount.It is a
good idea to reinforce the sub frame if you are using a
3.2L motor. Some times the engine mounting points rip
out from a lot of torque.

Cooling System: The radiator has to be out of an 88+ 325
E30. Some people use E36 radiators but if you plan on
using a mechanical fan E30 radiator will give you more
clearance. Speaking of clearance it is very important to
reinforce the transmission mounts or the first time you
slam on your brakes the fan will end up destroying your
radiator. The fan clutch has to be stock E30 with a
9-blade fan. Do not use an 11-blade fan because it will
give you less radiator to fan clearance. The overflow
tank has to be out of an 88+ E30 as well. Don't forget
to upgrade the thermostat housing and the water pump to
the metal kinds on your M50 motor. The bottom radiator
hose off the M50 motor will need to be cut down to fit
in E30. The top hose you can get from any auto part
store.

Note how little clearance there is between the fan and
the radiator, only about 7mm.Just look for a long
radiator hose with a 90-degree bend. The heater hoses
connect the same way they were on your E30 (the long
hose under the intake manifold goes to the top inlet and
the short hose that connects to the cylinder head goes
to the bottom inlet), do not eliminate the bypass valves
(recall items).

Lubrication System: The oil pan has to be out of an M50
powered E34 525I. You will also need to get the pickup
tube with a gasket and the oil dipstick. E36 dipstick
can be modified to fit but it will not show you the oil
level correctly. Do not forget to safety wire the oil
pump or at least locktight the sprocket nut. Drill a
hole through the oil pump shaft and the bolt, insert a
stainless steel wire through the hole and tie it up. M50
engines are known for the oil pump sprocket bots to come
loose.
Oil coolers are also a good idea for the track. Oil
temps get to about 240+ degrees if you drive your car
hard enough.

A/C: Just about every town has a shop that will
fabricate customs A/C hoses. When you get your engine
from a junkyard try to get the A/C hoses with it. Custom
hose shops will be able to connect the E36 A/C hose
connectors to your existing E30 hoses. You can also get
some fittings from your local hardware store and clamp
the hoses together yourself. Don't forget to flash out
your system to get rid of all R12 oil. Use PAG oil only
with your E36 compressor or it will not last you very
long.


Differential: The best ratio for 3.0L or 3.2L cars is
3.25 and the best ratio for a 2.8L or a 2.5L is 3.46.
3.25 differentials can be found in E28 525e 535I E24
635. 3.46s can be found in same cars but are more rare.
The output shafts and the rear cover have to be swapped
to make the differentials work in E30. You can also get
a rear cover out of an M Coupe. The M Coupe covers lower
the differential oil temperatures and look very cool
behind your E30.



Exhaust: Exhaust is truly something that should be left
to a professional unless you are an experienced welder.
You can use the stock E36 cats out of a 92-95 325 or M3
but the right side pipe will need to be modified to
clear the control arm bushing mount.

As you can see the right side exhaust pipe is still very
close to the control arm bushing bracket. In this case
there is only about 5mm of clearance.

The O2 sensor mounting port interferes with the frame
reinforcement behind the transmission mount. You can cut
a chunk out of the brace to make the O2 sensor fit and
reinforce the brace by welding it to the transmission
mount with a couple of pipes.
96+ exhaust pipes are larger in diameter then 92-95 and
pose some clearance issues. 96+ exhaust pipes are bigger
in diameter on the outside but they are double walled so
in reality they don't flow more then 92-95. OEM pipes
are stainless steel and a very hard to weld unless you
are equipped to weld stainless steel. Stock cast iron
headers from 92-95 can be used.

You will need to make some 5 mm spacers for the engine
mounts to raise the engine so the pipes clear the sub
frame. It is also a good idea to remove the studs out of
the headers and use the bolts to mount your exhaust,
makes it way easier to get the pipes in there. The left
exhaust pipe will need to be flattened out to clear the
sway bar.
You can also use stainless steel headers from 96+ E36;
they look way better then the rusty cast iron headers.
To use the 96+ headers buy two O2 sensor plugs from your
BMW Dealer (originally install on a 98 323IS) and weld
up the air injection ports. The muffler is up to you but
the pipes to it will have to be custom made.

Steering: When you get your engine try to get the power
steering pump and hoses with it. It is a good idea to
replace your rack when you are swapping the engine. The
rack in an M50 powered car is almost impossible to
replace without considerably lifting up an engine or
dropping the sub frame, the oil pan sits very close to
the steering rack.
Suspension: Nothing needs to be done to suspension
unless you want to improve the handling of your E30. M50
engine is slightly heavier then M20 (around 60lbs
heavier). Although 60lbs doesn't sound like much you
will be able to feel it. Thicker sway bars do wonders on
M50 E30s.
Wiring and Electrical: The best wiring harness to use is
out of a manual 93-94 325I due to its simplicity,
although it is not that hard to modify a wiring harness
from an automatic car or a car with traction control and
EWS. The process is as simple as laying the harness out
on a table with a diagram in front of you and
eliminating anything that is not necessary. If you ended
up with a harness out of an automatic car simply cut all
of the wires out of the engine harness that belong to
the automatic transmission computer. Automatic
transmission computer is wired directly to the engine
computer harness; the only wire that needs to be
modified is a “brown/black wire pin 26 transmission ECUâ€a
need to be connected to any “red/white wire on the main
relayâ€a. ECU has to be out of a 93-94 325I with the Bosch
part number ending in 413. You can use an ECU out of a
95 325I or a 95 M3 but you will need a special chip that
eliminates EWS. To make the E36 harness plug in to your
E30 you will need to make an adapter. To make an adapter
you will need to get a wiring harness connector off the
E36 (body side) and an engine harness connector off an
E30 (engine side). See the excel spreadsheet for pin
assignments. The coolant temp sensor for the ECU has to
be out of an E36 and the coolant sensor for the temp
gage has to be out of E30 (single pin sensor brown).
Alternator has to be out of any 6-cyl E36, I prefer to
use 80AMP alternators but if you have a powerful stereo
you might consider using a 140AMP alternator (it will
suck up more engine power though). Starter has to be out
of any E36, Z3, E46 323 328, E34 E39 or E30 318is. Don't
forget to the engine ground strap, with M50 engine it
mounts on the passenger side of the car.

E30 Wiring harness connector Color 91 318is Color
325I IS E36 Wiring Harness Connector Color

(body side) (engine side)

Pin 1 (alternator charge) blue blue Pin 25 blue

Pin 4 (coolant tem) red/white brn/violet Pin 12
green/gray

Pin 5 (oil pressure) brn/green brn/grn Pin 23
green

Pin 6 (Diagnostic Connector) grn/wht grn/wht Pin
22 Grn/wht

Pin 7 (Ignition switch) green green Pin 21 green

Pin 8 (fuel consumption) white wht/black Pin 24
wht/black

Pin 9 (engine speed) black black Pin 20 black

Pin 12 (check engine light) brown gray Pin 8 gray

Pin 13 (fuel pump) grn/violet grn/violet Pin 13
grn/violet

Pin 14 (speed signal input) black/wht black/wht
Pin 14 black/wht

Pin 15 (starter thin wire) black/grn black/grn Pin
15 black/yellow

Pin 18 (starter thicker wire) black/yellow
black/yellow Pin 18 black/yellow

Oil Level Sensor

Pin 10 Blue


Pin 16 Wht


Pin 2 Gray/Grn

Note: Wiring colors can


vary depending on model and year of


your E30 and E36 wiring harness.



On 325E the fuel consumption gage signal and the tach
signal connectors are in the glove box. Speed signal
wire from pin 14 E36 connector has to be connected
directly to the green plug on the back of your
instrument cluster. Thin (black/yellow pin 15 E36
connector) wire that goes to the starter can be left
disconnected. The starter will still work.
_________________

[oze30]

[ian332isport]

Be very careful with info from the US, as it does not always reflect what we got over her.

[DanThe]

Be very careful with info from the US, as it does not always reflect what we got over her.

Second that,

Ignore anything related to exhausts for a start. They have a liking for using E30 gearboxes aswell which im not fond of.

[ian332isport]

Be very careful with info from the US, as it does not always reflect what we got over her.

Second that,

Ignore anything related to exhausts for a start. They have a liking for using E30 gearboxes aswell which im not fond of.

..and all the OBD1 bollox they have to deal with etc. I generally steer clear of any wiring charts as well. They are only accurate for the car/engine combo they did. It may well not reflect what you have. BMW did make a lot of small changes over the years/models, so make 100% sure you know exactly what each wire does before you connect it up.

[DADDG]

As a newbie its nice to find out these sort of variations before even starting a project like this

There must be a lot of guys & girls who would like to see a step by step guide on say a conversion like yours on disc,We all know that its not a 2 minute job to collate info so if you start now it would be a nice christmas present to the zone My preferance is M52 so when you get a spare 5 can you do that as well Only kidding

[Nick323]

Did you ever get down to doing your M52B28 conversion ?
I have a 84 323 that I want to do this with.
We can get single Vanos 2.8L motors here with Auto box, wiring loom and ECU from the UK.
Of course I'd want to go manual on it...