BMW Compact Track Car - 172k & no history

[helix402]

I’ve used an M3 27mm front bar with both a 19 and 20mm rear bar on an E46. Worked a treat with no understeer despite the theory.

[helix402]

I’ve used an M3 27mm front bar with both a 19 and 20mm rear bar on an E46. Worked a treat with no understeer despite the theory.

[Jhonno]

helix402 said:

I’ve used an M3 27mm front bar with both a 19 and 20mm rear bar on an E46. Worked a treat with no understeer despite the theory.

Actually due to the nature of BMW suspension, going with a stiffer front bar should actually reduce understeer!

[grahamgraham]

Brakes.

For my initial track days I'd just done the front pads & brake fluid (and fitted a new front calliper), but the discs weren't looking the best so I fitted new discs & pads all round.

I went with Brembo Max grooved discs and EBC yellow stuff pads. I see these getting a lot of hate so am prepared for all opinions...



All went on pretty easy. I also did a wheel stud conversion at this point, just to make it easier to get the wheels & tyres off.





I was a bit shocked about how low the torque setting for the studs was, seemed crazy, but everywhere said about the same so I went with it.

Wheels & Tyres.

When i got the car it had BMW Style 187's on it, these are originally from an E90 3-series and have a different offset to e46 wheels (et34 vs et47), meaning that the wheel rim would sit 13mm further out from the car. Basically the same as running a 13mm spacer and giving a 26mm wider track. But style 187's weigh 12.5 kg each! Just for the wheels.

After a lot of searching i found a blend of weight, price and fitment that i was happy with. BMW style 157





Only 9.1kg each so 3.4 kg unsprung weight lighter per corner and another 13.6 kg saved overall! The wheels are forged hence the low weight, apparently made by Fuchs. Wheels are also from the E90 3-series, and are et34 meaning i kept the (slightly) wider track. I'm not totally sold on the looks, but deffo prefer them to the originals.

Don't worry, the ///m sport logos are only stickers...

Tyres-wise, I decided on Nankang NS-2R, they use them in the BMW compact cup so that'll do for me. Tyres ordered from Driftworks for £80 a corner & on they went :-)



I sorted out the coilover ride height at this point also, up at the front & down at the back. it's 30mm lower all round IIRC. I'd prefer the back to be a little lower but the coilovers are on their lowest setting at the back, maybe it'll settle in time.

[grahamgraham]

DanG355 said:

Nice write up. Looking forward to the wheels update - always exciting to see a new set of wheels on a car and be interested to see what option you go with.

Wheels & tyres update now done Dan

[grahamgraham]

MrC986 said:

I'm sorry I can't help you on the alignment setup for your car as ours was sorted by a motorsport specialist who I think works off the old fashioned method rather than a computer based system!! Ours wasn't set to a fully optimised position as we drive it to/from the track days (complete with a spare set of wheels in the back all ratchet strapped down!), although we could have had the rear ride height dropped slightly more according to our suspension guru.

If you want an idea of the ride height, just ask but I won't be able to assist until the start of next month when we retrieve it from its winter storage. Setting up coilovers is very much a personal thing.

thanks, would love to know what ride height you're running at once you get it out of storage. I've got mine setup now and done a couple of days since, I'm happy with it at the moment, less body roll and more stability vs previous which was the objective. I'm sure i could optimise further over time

[grahamgraham]

helix402 said:

I’ve used an M3 27mm front bar with both a 19 and 20mm rear bar on an E46. Worked a treat with no understeer despite the theory.

The 325ti has a 26.5mm front & 19mm rear as standard so i'm pretty much running the same.

What e46 are you running these on??

[grahamgraham]

Jhonno said:

Actually due to the nature of BMW suspension, going with a stiffer front bar should actually reduce understeer!

interesting, anymore info on this please? what is it about BMW suspension that means this is the case?

[Jhonno]

grahamgraham said:

Jhonno said:

Actually due to the nature of BMW suspension, going with a stiffer front bar should actually reduce understeer!

interesting, anymore info on this please? what is it about BMW suspension that means this is the case?

It's to do with camber curve and roll centres. When you lower a BMW you lower the roll centre (often into the ground) and actually encourage it to roll more. Which means you end up rolling onto the outer tread/wall. The stiffer bar resists this and actually gives you more grip. (Higher roll centre is used to resist roll).

A stiffer front bar tends to give better turn in and mid corner, with a little bit of push on exit. A stiffer rear bar tends to give slower turn in and mid, with over steer on the way out.

Is my probably slightly over simplified understanding of it.

[helix402]

grahamgraham said:

helix402 said:

I’ve used an M3 27mm front bar with both a 19 and 20mm rear bar on an E46. Worked a treat with no understeer despite the theory.

The 325ti has a 26.5mm front & 19mm rear as standard so i'm pretty much running the same.

What e46 are you running these on??

I used to run these on E46 330d Tourings (don’t ask about making E91 suspension work-that’s a much bigger can of worms!)

[DanG355]

grahamgraham said:

Wheels & tyres update now done Dan

Thanks! I do prefer the new wheels with a decent weight saving too. £80 a corner for the tyres seems a good price for the track focused rubber.

[Superchickenn]

On the Yellow Stuff,

I run these on 2 of my cars

MK1 Seat Leon 1.8t which ive taken around the swiss alps and Nurburg etc

Peugeot 206 GTI

I find the pads work great on both cars, they dont deserve the hate they get. I think it was the older material. Since they have revised it a few years back they havent put me wrong.

[seiben]

Nice write-up - I'm a big fan of a cheap track-car build, and would have picked up one of these if I could have found one when I was looking!

I also use EBC yellows, with stock (non-grooved) EBC discs. The internet will tell you you're going to die the first time you stand on the pedal, but I've run them for 5 years in sprints and trackdays and found them to be very good.

[grahamgraham]

Thanks for all the positive comments guys, much appreciated.

Another couple of track days completed since the last update, including an all day tuition session at Bedford as part of the 'MSV track academy'. Basically you get your own instructor for the whole day, i've got to say it was amazing, very worth the money. Improved my driving massively. Garry who I worked with for the day was great at explaining what I needed to work on & where to do what. Quickest laps of the day were 3:04, which I was v happy with in my 20 yr old banger.

Had a few hairy moments including a 80mph off at the chicane on the main straight, but the beauty of bedford is that there isn't really anything to hit, so we slid across the grass, managed to not get stuck and then just cracked on! (you might notice the mud on the bumper in the pics)



Before Bedford i got a lovely OMP 330mm semi dished wheel as the old shiny leather on the BMW one was difficult to grip at times. Love the new one, but i got very black hands, any thoughts on this? I guess gloves is the answer, but I really don't think i'm a good enough driver to be needing gloves!?

[grahamgraham]

re alignment, after i'd finished all the suspension work, i went for the following setup. I've done 3 track days with this now and quite a few road miles and i'm happy with it. Has good (enough) turn in, stable at speed and the tyres aren't wearing unevenly.

-2 front camber (almost)
-1 rear camber
0.05 front toe
0.1 rear toe

For my setup, caster isn't independently adjustable, just a product of the other elements, but it came out with one side half a degree different to the other side, seems pretty weird but drive fine so i'm not getting too worried.



Ignore all the red btw - that's just vs the standard settings for the car

[motorhole]

Great little track cars these! Quite rare too, not that many were sold in the grand scheme of things.

At some point it's worth taking the sump off and at the very least remove and replace the oil pump sprocket nut with loctite and drill/safety wire it in place. Or even better get one of the reinforced shaft & sprocket kits. They can back off of their own accord under sustained high rpm usage causing the sprocket to drop off and subsequent loss of oil pressure. I know personally of 3 people this has happened to! Useful piece of mind for a couple hundred quid.

M54 sumps are poorly baffled compared with M52. I don't know if an M52 sump bolts right on or not - if it doesn't, there are aftermarket baffle kits available.

I also have some Braid wheels available if you're interested! White, 16x7 ET32 iirc. Already fitted with 195/50/16 MRFs with a couple trackdays in them. Lightweight and strong with loads of brake clearance

[grahamgraham]

motorhole said:

Great little track cars these! Quite rare too, not that many were sold in the grand scheme of things.

At some point it's worth taking the sump off and at the very least remove and replace the oil pump sprocket nut with loctite and drill/safety wire it in place. Or even better get one of the reinforced shaft & sprocket kits. They can back off of their own accord under sustained high rpm usage causing the sprocket to drop off and subsequent loss of oil pressure. I know personally of 3 people this has happened to! Useful piece of mind for a couple hundred quid.

M54 sumps are poorly baffled compared with M52. I don't know if an M52 sump bolts right on or not - if it doesn't, there are aftermarket baffle kits available.

I also have some Braid wheels available if you're interested! White, 16x7 ET32 iirc. Already fitted with 195/50/16 MRFs with a couple trackdays in them. Lightweight and strong with loads of brake clearance

Yes, there's not many of them around I don't think, understandable when you look at the front. lol.

Thanks for the tips on the oil pump sprocket, I have heard about this (also, saw the chris fix 330i blowing up on you tube, though i think they concluded it wasn't due to the pump in the end), worrying that you know of 3 people who've suffered with this - eeek.

I think an M52 sump does fit actually, the gaskets are the same so implies they are the same fitment, not sure if it would clear everything else in the car though.

However... the eagle-eyed among you will notice that i've not touched the engine at all in this project... yet...

Ooh, Braids sounds cool, but i think i'm sticking with 17's for now.

[grahamgraham]

Ever since i got the car, the bumper was always a little off on the drivers side - it's clearly had some sort of bump on that corner at some time in its life as the fog light was out of line and there's a mark on the wing.

So i whipped the bumper off to investigate...



and the cause of the wayward bumper became apparent... the mounting bracket for the bumper should be riveted to the wing, this one was cable tied, they hadn't even chopped the end of the cable tie off!

The arch liner also has a big hole in many cracks it in, BMW didn't have a new one available and track time was booked for the following day so i did a bit of cable tie stitching as a temp fix (they're a great tool in the right place!)





Bracket riveted in place and bumper back on with much better alignment - woop woop

[grahamgraham]

Toward the end of my last track day, I got the unnerving brake pad warning light on the dash - they still felt ok and I was having a great time so kept going for a lap or two, then there was a few worrying noises so i headed into the pits. Upon inspection the pads were totally gone. A little concerning how they went so quickly from warning light to having nothing left...



(got my money's worth there!)

So having gone through a whole set, my thoughts on EBC yellow are...
- good performance for the price
- always felt good from cold through to pretty hot
- always had nice progressive feel
- never had brake fade even with 25+ minute sessions (Fluid is RBF 600)
- don't last that long (4 track days (2 days + 3 evening sessions)) + a bit of road driving

I've gone for EBC blue for my next set of pads - should give more longevity but similar performance...



Fitted but not tracked yet, so i'll get back to you with thoughts next week

[Sf_Manta]

EBC might be easier on the wallet, but they really don't last.
Someone who came with me when i was going out to Nurburging before Covid managed to destroy a set of EBC greens? inside of 4 laps there.

I'd recommend trying Ferrodo DS2500's to get a good pad with decent track performance and still useable on the road, and maybe setup to DS3000's or Pagid RS range.