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OMG that is AMAZING! Some seriously impressive work there Nigel!

What an update, well worth the wait

Thanks guys! I have a few small updates to come in the next few days, still trying to get this thread back up to date.

Rob, thank you. It was your original M50 thread way back (8 years ago??) that convinced me to give the original M50 swap a go. Look what you started

Yes please, keep us updated on this lovely project

welcome back nige, glad to see you have been well. car looks awesome,

whats going on with the brake master? does it provide as much boost as the original setup?

I look forward to the updates!

I had your thread almost permanently open when researching for my own project, and still refer to it regularly for reference/inspiration!

Ha thanks Splitty, nice to know the thread is a good reference, i refer to it sometimes just to remember what i have/haven't done!

Hey Nas! I see you sold your M52 car. Must have been hard to let that go. Re brakes. I cant remember the master size i ended up with, but it was definitely trial and error (3 goes) before i found a master size that gave me good feel, without excessive travel. It now doesn't feel much firmer than stock tbh, i tend to quickly forget it doesn't have a booster when driving it.

So i had a trackday at Sandown Racetrack in 2014. Sandown has a noise limit of 76db as measured 30m from the track. I was given the tip by a friend that running open trumpets on a S50 will get you booted off track. I refit the the stock airbox though it had to be modified to fit in between the towers. The volume of the box itself isn't an issue however the inlet pipe had to be reworked...

Car ran pretty faultlessly all day, water temps on track never went above 95C, oil however rose to around 130 toward the end of the each session. Car maintained oil pressure all day, not something normally to be overly excited about, however with the amount of fabrication that went into the sump pan, i'm happy it is working as intended! I then relocated the oil cooler and temps have now dropped to around 105C when driving hard.

Finished the day with a 1.33 without pushing the car too hard. Car is still on street tyres, stock e21 rear discs/pads and no LSD. It did highlight the fact that i desperately needed an LSD. I have since fitted a 3.91LSD and have a spare 3.45LSD.



Some pics from the day

Been playing with the exhaust a bit, finally pretty happy with it. The noise these S50's make is addictive. Motor doesn't like being under 2k with the light flywheel, but that's fine by me.

Here a vid of the exhaust. Lots of full throttle stuff from about 2:00 mark onwards



Can probably tell its geared pretty tall in that vid with a 3.45 diff and Getrag 260 box.

It has a 3.91 LSD and i'm in the process of putting the ZF 320z 5 speed in it. I may go back to the 3.45 once the ZF goes in.

Currently have the motor out for a freshen up. Only rebuilt the head last time around. I've decided to pull it apart for some new bearings, slightly higher comp pistons etc. Will post the final spec of the motor when its completed.

All good then, and you must have had tons of fun. However, no overheating the brakes?

Hey Jeroen, i had the 300x32mm wilwoods on the front so temps were not much of an issue on the day. But i was really only doing 6-7 fast laps at a time.

Having said that i recently sold those brakes. They were really too big, much bigger than needed for an e21. I also could only fit certain 15" wheels over it which is why i've been running 16x8 BBS' RS on it lately. I'd really like to put my 15" Riken Turbos back on this car soon.

I've almost finished making a smaller wilwood brake kit that works with stock 255x22 E21 vented rotors and also mini cooper 276mm rotors.
I'll post details soon, id be happy to make a few extra sets of caliper brackets if anyone is interested.

Ah ok was already wondering as I overheat my brakes within a couple of track laps, and that's with a stock 2.3 engine! I use the Wilwood 4 pots which work very well, but on the stock discs (like I have now) you run into issues, just not enough material to dissipate the heat I guess. Haven't looked into the option of brake ducts yet, may be the first step for me, but with that engine of yours I'd definitely try to source a larger disc. If you go 275-285mm you have much more material and will still be able to use 15". Haven't found a more or less bolt on option in that size myself though, but you may want to investigate this further and adjust your brackets to that.

Finished the new brake kit for the E21 that will fit my 15s.

Brakes are Wilwood Forged Dynapro's and E21 Vented rotors for now. I've designed the brackets so they can be mounted on either side of the mounting ears on the struts which allows me to upgrade to 276mm Mini Rotors with the same calipers in the future. Luckily 323i and Mini both share 22mm rotor thickness.

I've also been working on a new set of wheels, can't wait to get some 15" semi slicks on the car.

That will look great, but I really dig your old wheels. Are they for sale?