e36 325i Coupe Project

[wrs 118]

My 1992 E36 325i Coupe has just ticked over 324k's and is fairly buggered. Shortly it will be getting a new engine and manual conversion.

I'm tempted to wait another 1000km's so my 325i will have done 325k's...

The current engine is M50B25nv with a Jatco trans and everything else pretty stock.

The trans was fully reconditioned under insurance about 11 years ago and has done 210k's and is still going. The local trans-shop did a very good job!! It's near buggered again now though - the jerk is back and it flares a bit from time to time.

What's going in:

M50B25nv stroked to 3L (M54B30 internals)

S50 Schrick Cams + Vanos conversion & oil filter housing from a M52B28 (this is supposed to work)

Update - S50US Schrick Cams...

Getrag 6-speed manual conversion kit

M3 Full Exhaust

Update - Including Headers

New all Ally Radiator

Link G4+ ECU

M50TUB25 Wiring Loom

The engine will be dyno tuned.

Using the Link ECU means I should be able to use the M50 crank and cam sensors but will learn if this works at startup.

I have a M52B28 donor engine to rob all the vanos parts required. Depending on advise the injectors may also be used from the B28.

With the B28 available to rob parts off, if crank sensors, harmonic balancers, cam sensors etc need to be change over to get things working they will be immediately available to install.

Many hours of research has gone into the project to make sure all the interchangable parts will fit but due to the amount of conflicting info on the net I'm not 100% sure all the ducks are lined up. The non-vanos to vanos conversion of the M50 head should be straight forward - the S50 cams will drop straight in and only the front right corner of the casting need to be dremelled a bit to get the vanos clearance. The two heads share the same vanos gasket and same cam trays.

The reason for using the M50B25 as a base is so the car looks stock when the bonnet is opened.

At this stage the car will be going into the workshop in just over a week.

Have I missed anything, that's going to bite me?

Edited September 12, 2015 by wrs

[thorburn 120]

just your accountant. Who is doing the work?
Are you using the non vanos head with all the valve springs etc?

[wrs 118]

Yes, it's an expensive upgrade and certainly not worth it based on the car value but that's not why we make these changes...

Yup, keeping the NV head to get the 7mm valves and double valve springs. The cam trays are the same as the 93 & later M50 vanos so S50 cams will drop stright in.

[Ahmedsinc 414]

S50 used solid lifters, look further into that before making too many plans. Unless you're referring to S50US stuff, in which case they're fine.

M54B30 internals will result in a lower static compression in an M50 block due to the M50 having a slightly taller deck height. Drops from 10.5:1 to somewhere in the low 9s from what I've read.

M3 exhaust won't be worth much to you unless you use the S50B32 headers as well.

Were I in your shoes I'd swap the gear into the M52B28. Weight savings from the alloy block improve your power / weight, and the MS41 DME can be reflashed in the car by the likes of Gavin. Far cheaper option than going full standalone ECU. Better flowing intake manifold than the M50

NV heads can be converted to vanos, but there is some machining to be done. Again, why bother when there's a Vanos engine at hand? Not meaning to p*ss on your parade but it does seem to be making things more complicated than is necessary

Btw, stroker engines FTW!

[wrs 118]

No worries, p*ss away :-)

I want to find out any issues before the car goes to the shop...

The main reason for using the non-vanos head is the M50B25 stroker is already built - I purchased it already running at a much lower price than I could have buit one for + it already runs (risk reduction). I don't want to take the head off an already running engine unless I absolutely have to. I'm not sure what was done about the compression - seems to go alright though, much better than my 2.5L. The engine was built by one of the guys at HellBM so they've hopefully done something to sort out the lower compression (or maybe not so I'll check) - didn't know about this issue prior to buying it.

I suspect most of the parts have or are coming from members of this site.

Yes, S50US cams so should be no problem. Did accidentally get a set of S50 Euro cams and found they wouldn't fit - duh!!

I have the full M3 exhaust including the headers coming.

The M52B28 is buggered - got it for almost nothing + I want to keep the M50 so the car looks as stock as possible.

I have a M52 inlet manifold - if it flows better than the M50 then it would be fairly straight forward to swap it while the engine is still out of the car (could just swap it, injectors and all). I thought the M50 flowed better but maybe this is just the M50 non-vanos vs the M50 vanos manifold.

Yes, I am making things more complicated than they need to be - it's all to keep the car looking as standard as possible.

Thanks for the input though - possibly have a gotcha already (compression)...

[Ahmedsinc 414]

Ahh, that tends to make a bit more sense then.

M50 manifold does flow a lot of volume, but the M52B28 does make a little more bottom end torque. Vanos on the earlier engines tended to smooth out the torque curve compared to the NV engines, I think it pushed the curve slightly further to the left as well. Given the B30 internals make more torque I'd be wondering if it was worth the trouble. How flogged is the M52 anyway? Could just swap the heads across and save all the extra work? What is the duration and lift spec of the Schricks? Buying new or have you found some used ones locally?

[wrs 118]

I tried to find used S50US cams locally but no luck. Must have called 50 used parts suppliers. Didn't think about asking here though :-(

Ended up getting a set of New Schrick cams - ouch!!! So, standard US S50 duration 252/244 - should be much better than the standard 240/228.

At least with new cams the risk of problems should be reduced.

The M52 was cooked - very low compression and I'm not sure what state the head is in. I only got it because it was very cheap, much less than buying the vanos bits I needed for the the nv to vanos conversion separately. I also wasn't considering the possibility of swapping more major parts at the time I picked it up either...

I'll be replacing the M52 vanos seals before using it too.

Re M52 manifold - really worth doing or not? As you say, the vanos and B30 will make a big difference to the low-mid-end torque already. As long as the M52 manifold doesn't reduce torque at higher RPM and helps increase low-mid RPM torque then it's worth doing. I've had a M50B25nv for 13 years so I'm fairly used to no low-end torque but lots of revs (car before the E36 was a Ford Escort with a 2L Sierra engine running Cosworth A6 cams 5000-9000RPM) - I've always been a bit of a rev-head. However, this project has the opportunity to improve round-town drivability too so if low-end torque can be improved without affecting high-end torque, definaely worth doing.

Edited September 16, 2015 by wrs

[wrs 118]

The stroker compression has been confirmed to be 10.5

I did a bit of research regarding the M50 vs M52 manifold. Looks like the M50 is the one to use as it flows significantly better at high RPM. There will be little to no impact on low-mid range torque due to the addition of vanos, cams and the Link ECU. It will certainly be much better low-mid torque than just leaving the standard non-vanos M50 cams in the engine with no vanos... I found a good dyno test showing the M50 manifold makes a big difference at high RPM. The configuration I'll be using will be similar to the second to last test (with the 252/244 cams).

http://www.motoiq.com/MagazineArticles/ID/3351/Tested-S52-vs-M50-Manifold-and-the-TMS-Stage-2-3-Packages-for-the-BMW-E36-M3.aspx

Since the engine will be dyno tuned I should be able to get the graph to post here...

[Toast 117]

While they accurately show how without a tune the manifold has flaws, they don't backup their claims by giving the M52 manifold a tune also. I think for the whole thing to be fair the M52 should get a tune with the same bolt ons and then compare. If you're in Auckland I'm running an M52B28 with the same cams as you (and a tune), if you wanted a demonstration before committing either way I'd be more than happy

[wrs 118]

Thanks for the offer. I'm in Napier so a bit out of the way. I'm already committed to this path and the car is going into the shop on Monday for the upgrade so a bit late to make changes now...

One other change being made not mentioned so far is the MAF is being removed so MAP & TP will be used instead. This should help remove a little more restriction from the inlet.

Will report back how it goes + any problems found along the way.

Edited September 17, 2015 by wrs

[wrs 118]

After almost 1 week at the shop some pretty good progress has been made with a few learnings along the way.

The non-vanos head has been converted to vanos and the Shrick M3 cams installed. The cams were a bit tight and had to be ground slightly to fit properly. The old cams and new were sent to the local engine shop and the journals on the new cams ground to match the old. I don't know how much needed to be removed but the outcome worked out well. The vanos bolted straight up.

The modified wiring loom had 2 issues with connectors not matching. The were some male/female differences - appear not all M50TUB wiring looms are created equal. This will be resolved but cutting off the wrong plug and solder/heatshrink the correct plug onto the wiring loom.

The maunal conversion is done. The supplied manual conversion kit came with a dual-mass flywheel which I wasn't too happy about. The supplier said they would provide a single mass but... To save mucking around and because time was short I decided to just buy a solid flywheel kit from NZAD - they had one in stock. It meant no shagging around trying to find an E30 flywheel and matching components to work in the E36.

The engine and gearbox were being attached this afternoon and re-installed into the car. The driveshaft supplied in the manual conversion kit was for a 5-speed and a 6-speed box was supplied so the driveshaft is too long. I knew this and accepted it prior to being shipped. Tomorrow the driveshaft will be sent out to be shortened to suit.

All going to plan the driveshaft should arrive back on Monday. On Tuesday the car will go in for dyno tuning and I should get it back Wednesday.

I'm going to ask for the dyno plot so I can post it here - not sure what will be achieved re KW but should be reasonable - assuming nothing goes wrong...

Other mods not listed above that have evolved since the original post:

Cold Air intake added - DIY airbox built where the old airbox goes + Greenfilter pod-filter and 76mm direct pipework added. The MAF has been deleted.

The purge filter has been deleted and a carbon filter to atmosphere added to the fuel breather.

The Oxy sensor has been deleted.

The link will be tuned using MAP, IAT and TPS only. Knock sensors will only be used as a security measure.

The main cooling fan has been deleted and a 1980CFM push-mode electric fan added controlled by the Link ECU.

The airconditioning control, aircon radiator and wiring has been deleted (never worked since I purchased the car 13 years ago so why bother with it now)...

Will report back once all going...

Will also try to get some photos...

Edited September 24, 2015 by wrs

[Gaz 1042]

Any reason you went with the 6 speed gearbox? What are you doing with the diff?

Keen to see some pics!!!

[wrs 118]

I'll take pics this weekend.

6-Speed box has 0.83 top ratio.

I'm starting with the original auto diff @3.7 and the 6-speed drops the 100km/h RPM from 3160 (5-speed) to 2620. If this turns out to be too high and too fuel hungry I'll consider changing to a 3.4 which will make 2400 @ 100km/h. With the 3.7 diff the pick-up will be much better...

Depending on off-the-mark performance I could even look at a diff ratio down around 3.1 as this would mean a single gear-change to get to 100km/h vs 2 changes (102km/h at redline in 2nd (@6800)).

Edited September 24, 2015 by wrs

[Gaz 1042]

Interesting, keen to get your feedback when you're done. I've gone with a 6 speed as well but I've also got my hands on a large case diff and complete rear subframe from an evo m3.

[wrs 118]

I went into the workshop today to check out progress and do a bit of wiring - sometime handy being an electronics engineer...

It's looking pretty good. Everything is in except:

Coolant Overflow Bottle - doesn't fit on the all alloy radiator. This will be mounted elsewhere.

Driveshaft - the wrong front half was supplied and doesn't fit - looks like it came off a 318. The correct one will be sent out on Monday.

Today I installed the Link ECU, changed the wiring for the AIT sensor (as we're using a LInk one in the inlet pipe vs the BMW one in the manifold), installed the relay and wiring for the 1980CFM electric fan and connected the relay control to the old pirge-valve cabling. The USB lead from the Link ECU was also put through into the glovebox for easy in-car access.

Left to do is create a 1mm alloy sheet air duct for the bottom of the radiator - removing the airconditioning cooler also took out all the air directors and surrounds so new ones must be fabricated of most of the air will bypass the radiator and go under the car.

Here's the engine installed now looking like a M52 due to the M52 Vanos, Cam Cover, Coils and Oil Filter Housing

More pics to come of the gearbox etc.

[wrs 118]

One thing hopefully someone can help with as I'm getting a bit of conflicting info from manuals and Google;

Has anyone done a manual conversion replacing a Jatco Trans before? If so, the wiring diagram data and wire colours don't seems to match up for the reversing lights. My car appears to have a brown wire for the reversing lights going back to the X20 connector, pin 10 (engine loom side) where all the drawings I have say it's supposed to be blue/yellow.

[wrs 118]

The car went in for tuning on Thursday but they couldn't get it to go so I missed my dyno slot...

I got it delivered home to try to sort it out.

The first problem was the camshaft sensor - wrong type. I'd assumed the M52 camshaft sensor was the correct type but it was VR. The wreckers supplied a hall-effect type and this fixed the timing issues for the cams.

Next the timing was out for the crankshaft - had assumed the link could be easily adjusted to use the M50NV crank pulley but it turned out to be too difficult.

The crank pulley was changed to a Vanos type with the notch 120' further back.

Now the engine cranked with no timing errors on the PCLink software. It would not start though.

This was traced back to no fuel - the installer had accidentally swapped the feed and return lines... Once swapped the engine started no problem.

I went for a quick drive with just the basic map in the Link ECU - runs a bit rough and I didn't go above 2500RPM or give it much gas but very good for untuned.

It will now go back to the dyno for tuning next week sometime.

[wrs 118]

Yay, my car survived the dyno-tune (see below).

There was really only one unknown going into the dyno test - would the cams and Vanos work properly at higher RPM's (no valve clearance issues) - tick, ok!!

Overall I'm happy with the end result. The 6-speed box is great. Having driven the car as an auto for 12 years I now have to learn to drive it again...

It goes very well compared to the old stuffed engine @ 325k's...

Mistakes:

Used the M50 injectors - bugger. They max out at about 6k RPM. Also the intake appears to be a little restricted despite best efforts to improve it - may be the throttle body....

I may consider changing to S50 injectors in the future but that would require a re-tune. Maybe in a while.

Todo List:

Move the radiator overflow bottle back to the front of the car.

Tie in the evaporative emmission canister.

Get new caps for the engine covers.

Get new bonnet struts so I can throw away the stick.

Bleed the clutch - engages just off the floor + feels a bit soft at the start of the pedal movement.

Learn to drive...

Edited October 5, 2015 by wrs

[Ahmedsinc 414]

Any particular reason why the dyno run was done in 4th get as opposed to 5th which is 1:1? Or is it a typo?

Edited October 5, 2015 by Ahmedsinc

[wrs 118]

I think it's a typo.

Here's what I worked out as the speeds.

My diff ratio was 3.69 (Auto) and I'm doing 2600 RPM in 6th @ 100km/hr so I think it is in 5th...

Setting Mx RPM to 4300 I get

Max RPM 4300 Diff Ratio 3.69 Tyre Dia 0.62 Circum: 1.9477874

Gear Ratio Initial Speed Revs RPM Drop Top Speed RPM RPM @ 100km

1 4.23 0.00 0 32.4 4300

2 2.51 52.66 4400 54.7 4300

3 1.67 88.83 4925 82.0 4300

4 1.23 133.24 5525 109.8 4300

5 1.00 178.37 5975 136.2 4300

6 0.83 221.18 6150 164.1 4300

This shows 136.2km/hr @ 4300 so pretty close.

Here's the original calcs (assumed 6800RPM):

Max RPM 6800 Diff Ratio 3.69 Tyre Dia 0.62 Circum: 1.9477874

Gear Ratio Initial Speed Revs RPM Drop Top Speed RPM RPM @ 100km

1 4.23 0.00 0 50.9 6800

2 2.51 52.29 4400 2400 85.8 6800

3 1.67 88.12 4950 1850 129.0 6800 5272.906

4 1.23 132.44 5450 1350 175.1 6800 3883.637

5 1.00 179.82 6000 800 215.4 6800 3157.429

6 0.83 221.18 6150 650 259.5 6800 2620.666

RPM @ 100km in 6th 2620.6658

Edited October 5, 2015 by wrs

[wrs 118]

Here's a complete list of what was done and what was learned on this project.

Credit goes to the installer and tuner who with permission I'll post their details later.

Vendor Details:

Installer: Garry - Andrew Hollywood Motors Napier. Garry got everything sorted really quickly and did a really good job (total 40 hours to do

everything). There were a few minor issues with things not fitting as expected or gaskets etc which were resolved quickly. Garry's

familiarity with the E36 certainly made the conversion much simpler than having attempting it myself - thanks Garry.

Tuner: Graham Neale - WRC Developments Napier. Graham did a very nice job, was very professional and manage to fit me into his very busy

schedule at relatively short notice - thanks Graham.

Basic Stuff: Me (cold air intake, engine loom modifications, ECU fitting, car electrics, electric fans)

This project was to take E36 325i Motorsport Coupe and replace the old tired engine with something that still looks like the factory original but goes a lot better.

Requirements:

Everything must be bolt-up and look BMW factory standard albeit not original to this car. Must still look like a 325i engine and running gear.

Parts Required:

M50B25NV Engine

Keep the M50NV manifold + injectors

M54B30 donor crank rods and pistons

Manual Conversion

M50B32 6-Speed Box

NZAD D1 Racing Clutch Kit + Lightened Flywheel 6.5kg (Trademe)

Pedal box + master cylinder

Slave Cylinder + other clutch bits.

S50B32 Headers

S50B32 Exhaust

ZF Driveshaft Front Section (needs to be shortened for the 6-speed). Could not use a complete M3 driveshaft due to the diff flange being different.

S50US Cams - used new Shrick 252/244 cams (Turner Motorsport)

M52B28 Donor Engine for:

Vanos Unit

Harmonic Balancer

Oil Filter Housing

Vanos Oil Line

Cam Cover

Plastic Engine Covers

Knock Sensors

M50TUB25 Wiring Loom

got mine from an auto so deleted all auto wiring + the MAF wiring from the loom.

Link G4+ Plugin ECU

New Fuel Pump

New Fuel Filter

Gaskets and Seal etc.

M50TUB25 Camshaft Hall Effect Sensor

Link IAT sensor

Greenfilter POD filter + Cold Air Intake mod (custom by me).

76mm Inlet tubing to POD filter.

Ally sheet + Eurothane Adhesive

Surprises:

The M50 Power Steering Pump does not bolt up to the M52 Oil Filter Housing and had to machine 15mm off one leg to make it fit.

The M52 camshaft sensor was VR - expecting hall effect.

Make sure you have the correct front half of the driveshaft before you shorten it (originally supplied the wrong one in the manual conversion kit and shortened it without noticing - duh!!).

Installation:

I purchased the engine already reconditioned and stroked to 3L with approx 3500k's on it. It was 3L M50NVstroker at that time with the M50NV head and cams.

I decided I wanted the S50US cams + Vanos to get better bottom end torque + rev ok.

I purchased new Shrick Cams from Turner Motorsport. These bolted striaght in with no issues. Had to use the M50NV cam trays and lifters. The M52 vanos was installed with no modification required to the head. I'd read some relief with a dremmel was required but maybe this is for the M50 vanos - did not need tomodify at all.

The M52 oil filter housing was installed + oil line to the vanos.

The NZAD D1 Racing flywheel and clutch was installed.

The gearbox was connected to the engine.

The wiring loom was installed.

The engine and gearbox was installed in the car. Everything bolted straight up with no issues.

The second driveshaft was measured and sent out to be shortened.

There was a problem with the Camshaft sensor as initially the VR sensor was installed - this has the wrong plug to connect to the M50TUB25 loom - should have been the give-away here... Later the correct sensor was sourced and installed.

The front section of the driveshaft was installed.

The exhaust was installed.

All done, ready to start.

No modifications were required to fit the engine, gearbox or exhaust to the standard mountings.

Problems:

Engine would not crank.

Had to locate the K1 start solenoid for the auto-trans start inhibit. On NZ RH drive cars this is located on the drivers side near the steering column - an orange relay on top of a connector block under the dash.. The relay was removed and the black/yellow wires cut off the relay holder. These were linked with a solder join + heatshrink.

Now the engine cranks.

Initially there was no camshaft pulses going to the ECU. The M52 VR sensor had been installed + a linking connector made to try to get it to work. This was a no-go and required a hall effect sensor (which has the correct plug so no adapter required). Leson here - the connectors don't mate then it's probably the wrong sensor... Camshaft timing sorted.

Initially the M50NV harmonic balancer was used. This puts the crankshaft timing notch 120' out from the M50TUB25. The M52 is the same as the M50TUB so the harmonic balancer was swapped from the M52 donor engine. Now all the timing was good.

Still would not start.

Turned out to be no fuel due to the in/out being accidentally swapped - only mistake the installer made and not unreasonable given the two pipes are side by side... With the fuel problem sorted it started no problem.

The Vanos Solenoid did not work - was faulty so replaced with one that worked.

Tuning:

The MAF was deleted so the Link ECU was tuned using only MAP, TPS and IAT.

Dyno tuning was required due to the significantly different configuration to the base map supplied in the ECU. The fuel map was way out and far too lean initially. Once tuned it's really smooth and all surging has gone. There's very good transiet throttle response too.

Learnings:

Use S50 injectors as M50 are too small.

Everything else worked out pretty well.

Unplanned Costs:

A few extra costs due to machining the Power Steering Pump and having to shorten the driveshaft + extra costs from missing the first dyno run due to no-start problems. Make sure it runs before sending it for tuning!!! I didn't try to start it initially as Link ECU's need to be unlocked before they will run. I didn't have a laptop to do this so left it to the tuner assuming everything was ready to go.

All in all was a pretty good project with no major problems and no catastrophic mechanical failures along the way. Now to enjoy the new lease of life on the car.

Edited October 5, 2015 by wrs

[thorburn 120]

If the injectors were correctly modeled in the ecu, you shoudn't have any problems swapping in new injectors.
Just change the master fuel and injector deadtime settings. If you go for well known injectors these settings will be easy to get/come with the injectors. Verify with a wideband after changing.
You can change the some settings and use the vr sensor and/or the non vanos trigger settings.

Very nice project,

[wrs 118]

Thanks, yes, I was wondering about the master fuel setting...

[wrs 118]

Hopefully someone can help with a clutch issue.

You have to push the pedal hard to the floor and the clutch engages just off the floor - maybe 5mm of movement. I've read in forums this is common on M3's. I have the 420g Getrag box from the 3.2 Evo and NZAD Solid Flywheel and clutch kit. This kit is supposed to be a bolt-up replacement with the same alignment as the dual-mass so should not be impacting the pedal response. They have said they haven't had any issues previously.

It already has a braided clutch line and the clutch has been bled twice with no bubble or change in response either time.

Does anyone know if this pedal response is normal for a M3 clutch?

Given I'm not getting much travel on the pressure plate tynes now is there an risk changing the throw out bearing to the E21 323i type - 5mm longer?

The gearbox looks like it has to come back out as there's a leak from the shifter seal... Will probably do all the seals if it has to come back out...

Thanks in advance.

[will 169]

I assume the kit came with a new throwout bearing? If so, it should be the correct height. Do not change it for one with a higher profile as you could then end up with a bearing that is under constant load. You need to confirm with them that the kit supplied suits the 6 speed box without any mods.

The hydraulic system can be a real b *tch to bleed. When you push the pedal down, how much free travel does it have before it loads up? Check this carefully using your hand, not your foot, as using your hand produces a better feel for determining how far the pedal travels before the bearing contacts the pressure plate bearing surface.

The other thing that can go wrong is the lever that the bearing sits in comes adrift from the pivot, or the pivot is damaged, resulting in increased travel before it contacts with the pressure plate.

My money is on the hydraulic system still having air in it...