The last few months have been spent gently nudging the car towards hopefully becoming a more enjoyable track car (without ruining it!) and importantly, equipping it better for more track use and longer stints. I have been kind to it so far with modest track time and shorter sessions, though with the goal of a trackday at the ring next year, it needs to be capable of many reliable sessions through a day. It takes a lot of effort and money to get to a TD at the ring, not to mention it's a dream trip for me, so I want to be able to maximise both my time on track and enjoyment.
On the topic of the ring, we made another pilgrimage in May, just the one 7 tenths lap in the daily as it was TF and I don't like the liability risk (hence not taking the Z4 or MX5).
Before I jump into those updates, I fitted the BDS intake and did some performance testing at a local airfield. Unfortunately the usable section of the strip isn't long enough for high speeds where power increases would be most apparent, but even at modest speeds, there was a material and repeatable improvement in performance.
Note kmph rather than mph, no idea why I had it set to kmph...
With three runs performed with standard intake and BDS on the same day, with temps a touch higher with the BDS intake, there was a material improvement, with the biggest speed sweep providing the most valuable data, all recorded with a VBox Sport. I'm satisfied the improvement subjectively and objectively is aligned to both my hopes and BDS' claims.
It is a shame to lose the loud intake noise from the sound generator, but the cruising volume is much more tolerable and it sounds a bit 'harder' at full throttle now. I played around with retaining something of the sound generator pipework, but have now removed it all and blanked off the bulkhead hole.
From going to stopping, I am hopeful of continuing to use the standard calipers and discs, preferred very simply for cost, both in terms of capital expenditure and operating. The car isn't terribly powerful, nor terribly heavy, so hopefully I'm in with a fighting chance!...
EBC Bluestuff pads and Brembo HC discs were OK at the track last year, I had bought some EBC RP-1 pads for the front, but they were the wrong fitment, so had to go with the Blues. These were OK if not infinitely confidence inspiring, so have bought some EBC RP-X pads for track use on the front, and I have also added fresh fluid (Motul RBF660 this time), brass caliper bushes and some cooling at the front, utilising the factory fog light apertures. Weight is about net neutral for anyone interested.
I will likely add some cooling to the rear too, be it by way of some generic ducts or some GT3-style air guides, I'm favouring the former at the mo, perhaps mounted on the underside of the swing arm.
As I have been going through working on the car, I keep wire wheeling where necessary, treating any rust with Jenolite and painting, most of the front is done now and I have just treated the 1 year old driveshafts (should have painted them) along with some corrosion setting in at the bottom of the rear KW shocks, to be painted next weekend weather permitting. I had to resist temptation to waste time and materials on rear trailing arms and hubs as these will be replaced with properly reconditioned parts after the winter.
Talking of trailing arms, I now have the Powerflex Black RTA bushes in, along with some Powerflex Yellow gearbox bushes, both fitted by a mechanic friend. I haven't noticed much difference in drive or NVH from the RTA bushes, though hope to be able to feel an improvement at the track. The gearbox mounts on the other hand have improved the shift notably, although they have also introduced a little unpleasant, if not intolerable drivetrain noise. I think a stiffer rubber bush might be the right compromise here, lets see how the car feels at the track and if they bed in at all.
Next on the list was some oil cooling, I have used an //M2 oil filter housing (thanks Damien for the tip), which has the oil outlet and inlet and bunged the factory coolant hose that feeds the factory oil/water exchanger on the N52 filter housing. The oil cooler itself is a generic kit that I have mounted to take air from the kidney grilles, I will put some mesh on the back of the grilles to protect against stone chips; thought I had some in stock, but apparently not.
View attachment 186188
View attachment 186189
Whilst I had the grilles out, I painted the centre section matte black and polished the surrounds, you can also see the fog light ducts and how much I need a new license plate. I also need new BMW emblems in a few places on the car, however I'm afflicted with a desire to buy BMW Anniversary badges and am giving it a little time in case the affliction passes!
Continued in next post...
North West Surrey
