Trackday Car Advice

[kevinday]

A friend and I are looking at buying an '87 BMW 325 coupe and gutting it for track use. We will strip out all unnecessary stuff and install a full cage, 2 seats and harnesses. Mechanically the car has a later version 2.5 with about 200bhp, and we intend to leave this alone for now.
If anybody could give me some advice on suspension and brake improvements I would be very grateful.

Thanks in advance

Kevin

[accident]

throw all the rubber brake hoses away and fit braided ones.
if your disks are ok then better pads will help.
a friend of mine has just fitted a spax kit(springs and dampers)to his track day 325,he thinks its great i think its way to soft.
it depends a lot on how you drive and how much cash you have to waste

[tonyhetherington]

Give a thought to just exactly how you're going to drive round the track.

I think perhaps that if you just want to have some good ol' fun that isn't your everyday car, then you can slightly upgrade certain aspects (pads, springs, weight) as mentioned above. However, if you're going to go the whole hog, and want to really challenge yourself and set up a car perfect for tracks to try and get the best time possible for that car on that day, then you should think about slicks, diff (due to slicks), brakes, ADJUSTABLE (ride height and or damper settings), quick change gear shift (tho dont know how good/bad these are for 325), cooling (ducts/radiator), stack dash (to log info about car's performance) .... the list will go on.

Really I think the question is also, how much money do you wish to spend? A friend and I were going to do a simliar thing to a 205, and we reckoned that £2k (considering our contacts and existing parts) would get us a sorted but reliable track monster.

Good luck whatever you choose to do !

[adrianr]

Don't forget that if you lighten the car you will effectively stiffen the suspension anyway. What you do depends on how good condition the car is in to start with.

I'd just make sure that
- it has a matching set of tyres on,
- there is at least 3/4 of the brake pads and discs left,
- the suspension bushes look OK and the shocks feel like they work
- that all the fluids have been changed recently
- engine mounts are good and exhaust is secure
- any engine belts are in good nick
- radiator isn't blocked and new rad cap fitted
- there aren't any fuel or (large) oil leaks

Then get the tracking checked, pref after you've done all the stripping out and you can do your first day and establish a baseline from there.

The main things to watch when taking a car on track are brake fade due to repeated use and oil surge. For brake fade just go carefully at first, and take some spare fluid and pads with you. For oil surge ask someone who races one, or fit a high pressure warning switch and a big light on the dash.

AdrianR


>> Edited by adrianr on Tuesday 2nd September 15:29

[kevinday]

Thanks guys, I am an experienced track day driver, though my colleague is not, he wants to learn how to drive faster than he does at the moment.
I am in two minds about how far to take the car, certainly two sets of wheels and tyres, to keep it legal for the road, I think we will have a fairly limited budget (I do not want to spend too much as this will put back the TVR purchase).
Brakes and suspension are my primary focus, Aeroquip hoses all round are definite, we will probably leave the standard brake discs for the moment, maybe a change of pad material. If they prove unsuitable through fade etc. then we will change the brakes.
Suspension - I want some easily adjustable shocks, with matched springs, anybody suggest which are most suitable, I think the weight will be close to standard with the fitment of a roll cage negating other weight savings.
Keep the ideas coming!

Kevin

[fergus]

How about pagid yellows, or greys (expensive for an axle set, but worth it), SRF or other high wet boiling point fluid, hoses (as already mentioned). Remove the backing plates from the discs to allow some ventilation around the back of the disc. Romove the fogs / fog blanking plates to allow some cooling air into the back of the wheel area.

Try uprating the a/r bars as well, but you'll need to ensure all your bushes are OK / replaced with polyeurethane ones first though.

Any spring people should be able to help you out. Try Faulkners, or ring Leda and they'll help you out. Their units although they can be custom built to your requirements and can be made fully adjustable, are not penske or ohlins quality (or price!), so can leak a bit of oil sometimes, but are easily good enough for trackdays.

Slicks are a bad idea with out sump baffling as a minimum. You will also place a lot of strain on your wheel bearings, which you may well hear whirring as you go round corners. Try dunlop formula R's, which are also road legal if you get stuck and are very good on damp (not wet) tracks.

I think you'll only really need a rear cage, rather than a full cage. Bolt in ones (4pt or 6 pt) don't add loads to the torsional rigidity of the chassis, so unless you get a full one which is triangulated onto the suspension mount points and down onto the diff carrier (& welded) I doubt you'll notice the difference (stiffness-wise).

Everyone is right though. Concentrate on brakes first, then suspension. Leave the engine alone till later - the on track benefits you'll notice will probably be slim. For the 325, the best cheapish performance enhancement will be to fit a lower ratio LSD to help acceleration. This can be changed in about half an hour and should cost about 250 from a BMW breaker (or try Nigel Moseley @ Moseley motorsport) www.moseleymotorsport.com/

Hope this helps.

Fergus

[fergus]

Also, re braking, don't trail brake into corners. You can get away with jamming your foot through the bulkhead unless you just need a dab. Pro racers seem able to take a 'standard' saloon round a track for several laps, whereas road drivers seem to insist on 330mm 6 pot AP upgrades....? (check out half the scooby brigade, all the gear, no idea...) (waits for a slating here)...

[steve lewis]

Interesting comments guys and good for discussion.
As an ARDS race instructor and also instructs in an M3 from the KUMHO challenge and EERC enduro races, this is what I have found.

Yes you can spend lots on re-specing the car, but initially there will be more time found through working on the 'nut behind the wheel'.

an earlier contributor suggested just getting the basics right on the car. I go with this.
fluids, hoses, tyres etc.
However I presonally would use DS 3000 brake pads (as used in the BTCC they do not need bedding in and will not fade. Also use SRF race brake fluid. It is expensive but will not boil no matter how hard used.

Rather than going for posh dampers at this stage try uprating the bushes where possible from rubber to nylon or similar race standard they are cheap enough.

Learn how to get the most out of the car you have to start with. Then maybe work on changing bits slowly. That way you can identify if they make a difference.
Change too much too soon and you will not know what has made the car better or has had no effect.

Hope this helps
Always happy to chat.
Best regs
Steve Lewis
07785 773341
[e-mail]

PS Don't forget the instruction :-)

[kevinday]

Thanks again guys, all points noted with interest, particularly Steve's comment about the nut behind the wheel, I just need to find an English speaking instructor here in Hungary....Zsolt Baumgartner...