BMW E39 M5 Touring build
Discussion
Using every bit of spare time available (without the wife divorcing me!) I have been pressing on to meet a deadline.
New parking brake hardware, new rear wheel bearings with the M5 hub flanges (note the two grub screw bolt holes non M5 E39's don't have), new discs pads and rebuilt callipers.
Saloon and tourings differ in where their parking cables pass through the knuckle, 12'o clock on the saloon and 9'o clock on the touring. This presents a minor problem in that the M5 uses bigger rear discs and there for bigger back plates so there a two options to address this issue, either weld in the centre of a touring back plate to an M5 outer or cut down the touring back plate to clear the M5 disc.
The latter is the route I chose as its easier and welding thin bits of steel and they have a shape critical to the operation of the parking brake.
Another saloon/touring difference that needed to be overcome was the rear brake hoses. On a saloon the hose come out of the calliper horizontally then attaches to the rigid pipe in a vertical position. On the touring the hose comes out at an approximately 45 degree angle then turns rearward to a horizontal join of the rigid pipe. The reason for this is to clear the shock absorber as again there is a difference in mounting points, the saloon being vertical in to the top of the inner wheel arch and the touring at about 30 degrees to the rear subframe (as can been seen in previous pictures).
To overcome this custom made HEL braided brake hoses were fitted to the rear with matching non custom fronts.
Bilstein B8 shock absorbers coupled with the existing Eibach pro kit front springs, new top mounts, all four arms new with the brake reaction (upper) arm bushes replaced with Powerflex, new M5 (like the rears two grub screw holes plus two locating pins) wheel bearings plus as per the rear new pads, discs and rebuilt callipers.
Front end coming together.
Along with the new fuel lines was fitment of the M5 specific fuel filter and pressure regulator set up.
And now on to one of the areas I enjoy with a build.........
The M5 body loom laid out.
As mentioned at the beginning of the thread, an E39 M5 touring build has been done several times before and having trawled the web to see others approaches I found that people have taken one of two ways when it comes to the wiring alterations required. Now I suspect their chose boils down to the base touring they chose to convert as to the approach they have taken, the two choices being alter the existing touring loom to suit or use the M5 body loom and alter it for the touring specific parts such as tailgate, self levelling rear suspension (if retained) with the latter involving a lot more work.
Other differences to throw into the mix is if the touring as ASC or DSC (all M5's have DSC), wether the touring is a Diesel or petrol and even more importantly if the touring was built before 09/98.
This is particularly important as the E39 had a major technical update from this build date (and all M5's were post 09/98) which also including a lot of the electrical components and wiring..
There are also differences between V8 and six cylinder cars and even after the 09/98 technical update there are a few slight differences.
The upshot of this is that the easiest touring to convert is a post 09/98 540i manual that is a similar build date to the M5 donor car.
Never the less......
..... using a 03/99 built 540i auto touring and an 09/99 M5 meant minimal wiring alterations to the touring loom but still plenty of wires to be harvested from the M5 body loom to integrate the Sport button (for different throttle map and steering), manual transmission and S65 vs M62 differences.
As with my E46 M3 touring project, all wiring alterations were done without cutting and soldering so all terminal numbers and wires colours are as per factory wiring diagrams.
New parking brake hardware, new rear wheel bearings with the M5 hub flanges (note the two grub screw bolt holes non M5 E39's don't have), new discs pads and rebuilt callipers.
Saloon and tourings differ in where their parking cables pass through the knuckle, 12'o clock on the saloon and 9'o clock on the touring. This presents a minor problem in that the M5 uses bigger rear discs and there for bigger back plates so there a two options to address this issue, either weld in the centre of a touring back plate to an M5 outer or cut down the touring back plate to clear the M5 disc.
The latter is the route I chose as its easier and welding thin bits of steel and they have a shape critical to the operation of the parking brake.
Another saloon/touring difference that needed to be overcome was the rear brake hoses. On a saloon the hose come out of the calliper horizontally then attaches to the rigid pipe in a vertical position. On the touring the hose comes out at an approximately 45 degree angle then turns rearward to a horizontal join of the rigid pipe. The reason for this is to clear the shock absorber as again there is a difference in mounting points, the saloon being vertical in to the top of the inner wheel arch and the touring at about 30 degrees to the rear subframe (as can been seen in previous pictures).
To overcome this custom made HEL braided brake hoses were fitted to the rear with matching non custom fronts.
Bilstein B8 shock absorbers coupled with the existing Eibach pro kit front springs, new top mounts, all four arms new with the brake reaction (upper) arm bushes replaced with Powerflex, new M5 (like the rears two grub screw holes plus two locating pins) wheel bearings plus as per the rear new pads, discs and rebuilt callipers.
Front end coming together.
Along with the new fuel lines was fitment of the M5 specific fuel filter and pressure regulator set up.
And now on to one of the areas I enjoy with a build.........
The M5 body loom laid out.
As mentioned at the beginning of the thread, an E39 M5 touring build has been done several times before and having trawled the web to see others approaches I found that people have taken one of two ways when it comes to the wiring alterations required. Now I suspect their chose boils down to the base touring they chose to convert as to the approach they have taken, the two choices being alter the existing touring loom to suit or use the M5 body loom and alter it for the touring specific parts such as tailgate, self levelling rear suspension (if retained) with the latter involving a lot more work.
Other differences to throw into the mix is if the touring as ASC or DSC (all M5's have DSC), wether the touring is a Diesel or petrol and even more importantly if the touring was built before 09/98.
This is particularly important as the E39 had a major technical update from this build date (and all M5's were post 09/98) which also including a lot of the electrical components and wiring..
There are also differences between V8 and six cylinder cars and even after the 09/98 technical update there are a few slight differences.
The upshot of this is that the easiest touring to convert is a post 09/98 540i manual that is a similar build date to the M5 donor car.
Never the less......
..... using a 03/99 built 540i auto touring and an 09/99 M5 meant minimal wiring alterations to the touring loom but still plenty of wires to be harvested from the M5 body loom to integrate the Sport button (for different throttle map and steering), manual transmission and S65 vs M62 differences.
As with my E46 M3 touring project, all wiring alterations were done without cutting and soldering so all terminal numbers and wires colours are as per factory wiring diagrams.
Moving back to the engine bay meant plumbing in the oil filter housing and PAS reservoir. These are located differently to the 540i and have their own bolt on mounting bracket compared to the (by now cut off and painted inner wing) welded on bracket the 540i uses.
[/url]Both plastic fill in panels from the 540i were replaced to allow for the M5 twin air intakes, both of these were damaged on the M5 donor so were bought new along with....
.....some of the most expensive bits of plastic known to mankind!
Due to the front end damage of the M5 donor car a lot of the front end parts were scrap. In the end a new fan blade, fan clutch, radiator, fan cowling, expansion tank and not pictured but replaced with new, both belt tensioners, belts and top coolant hose. Luckily the 540i shares the same front panel, PAS cooler. electric fan and AC condenser as an M5 so they could be reused.
What you see here is pretty much all the hardware required to mount an M5 exhaust which was all scrap on the M5 donor car. That pile there was about £500. That hurt!
Rear silencer mounting studs all wound in after running a thread cleaner through the holes.
Rear silencer heat shields fitted up with all rear silencer six rubber mounts. Another pair of parts that seem like a minor thing but were both missing from the donor M5 and had to be bought new at great expense for what they are.
Quad pipes on a wagon!!!
All the complication of grafting in the M5 boot floor, relocating the battery, the expense of all the new M5 exhaust mounting hardware just be able to have four pipes like an M5 saloon when I could have just used an alternative method with a lot less work an expenditure but it would have been a massive compromise for me.
The donor M5 had been de catted and had a rear silencer delete all done quite poorly. I bought a pair of used rear silencers from ebay so refitted those but a pair of used M5 cats a quite expensive now at circa £1200-1500 and ideally i wanted a complete uncut system from the down pipes to tail pipes so this unsightly exhaust is a temporary solution till a suitable system comes up.
Engine bay now built up with the intakes, fluids filled, petrol added to the tank, EWS, key barrel from the M5 fitted (for the time being) and it pretty much fired straight up!
Back onto the interior refit, as I had a deadline to meet (July the 4th E39 M5 meet at Caffeine & Machine) It was full steam ahead with every spare bit of time so a lack of pics during this stage im afriad.
The M5 front seats were sent to a mate at the polishing company east anglia to re colour the blue centres to black and these were back in time to refit.
A set of Michelin PS4's fitted up then Hunter wheel alignment to M5 specs.
After running up the engine up to temp, checking for leaks (and rectifying a minor coolant leak) it was time to take it for its initial test drive.
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