Z4M Track Day Prep

[Kern47]

Hi,

I've owned my M since beginning of last summer and loving the spirited road driving so far, but really want to get it over to Blyton Park in the summer months this year. Having never driven any car on a track day, I'm just wondering if I could get some advice on the prep before hand.

The car is on about 76000 miles and I'm having the rod bearings changed in a few weeks for peace of mind, so it will be having at least 2 oil changes between now and the track day (probably one just before to clear it from the bearing change, for peace of mind again).

The things that come to mind other than that, are gearbox and diff oil change (not sure when the last one was done) and brake fluid/pads.
Annoyingly, I noticed yesterday I've somehow picked up some brake judder so hoping to give the old 'hard braking' method a go to clear it, as the discs were new not long before I bought it.

A bit of a long post, but hoping I can get some peoples experience of how to prepare for a track day, mainly in terms of the brake system really, as that's what I really don't want to neglect...

Thanks

[buzyg]

Sounds like you have all the basics covered. Re brake judder, get your wheel balance checked. I almost wrecked a new pair of front discs, due to a slight imbalance on a front tyre. Thought like you that they just needed a bit of hear cycling and persuasion to bed them in. The standard ///M is not perfect, but it is perfectly happy on track, enjoy it.

[Kern47]

Yeah I might give it a little go to see if it sorts it, but if not then I'll get them to look at it when they do the bearings.

Do the standard brake pads and fluid generally stand up to a track day? I mean it is my first time on track so I wont be setting any records... just wanting to avoid the pedal hitting the floor lol

[BMWZ4MC]

The OEM brakes are pretty good but pad and fluid dependent. My Zed has seen a great many track miles over the last ten years and having tried a variety of options, I’d recommend EBC Bluestuff pads and ATE DOT 4 brake fluid (previously ATE Superblue now called TYP200).
I prefer tight twisty tracks that are more demanding on the brakes and with this combination, additional brake cooling and solid caliper bushes I didn’t experience any fade, no matter how much I abused the brakes (I have a tendency to brake hard and very late). However, the OEM set up can lack consistency of pedal feel when the brakes are really hot.
The Bluestuff pads are markedly cheaper than many of the competitors and perform just as well in my experience, although they are a little dusty. Similarly, the ATE fluid outperformed far more expensive fluids from the likes of Motul.

This is the brake cooling modification described by Exdos that I adapted slightly:

http://www.z4-forum.com/forum/viewtopic ... 24&t=38775

and these the solid brake bushes:

http://www.z4-forum.com/forum/viewtopic ... 24&t=45293

http://www.turnermotorsport.com/p-4118- ... e-kit.aspx


I’ve subsequently fitted an AP Racing BBK front and rear. I did this principally to improve the consistency of pedal feel. With the OEM set up, this could be a little lacking when the brakes were really hot. They always worked but modualting the brakes could be difficult which doesn’t inspire confidence when braking from 140mph into a chicane. Since I was shipping my car from London to Sydney, I need something that would perform as well at 35C ambient temperature as it does at 5C. The AP kit is immense and works exactly the same way and with consistent pedal feel after 2 laps or 20.

In terms of general advice for track days, I would recommend turning off the DSC. If you don’t, the brakes will overheat very quickly as the oversensitive system tries to manage your cornering by applying the brakes. I did three fairly slow sighting laps with the DSC on at a track new to me and the pads were smoking on all for corners when I came in. The rest of the day I drove hard with DSC off and had no further issues. Of course, you’ll need to be a little more cautious with your right foot with the DSC off, but you’ll also find the car really comes alive without any electronic restraints.

As you start going faster, you’ll find the ///M tends to understeer, so turn in a little slower than you think and carry the speed through the corner. Better tyres and adjusting the geometry will go some way to improving understeer, but in the end I only solved it by fitting coilovers and running soft compound track tyres. A happy additional effect of this was markedly reducing braking distances by reducing the pitching under braking and so allowing all four tyres to contribute to the braking effort.

Lastly, come in a lap earlier than you think you should before your concentration wanes, and make your last lap a cool down lap to keep air flowing over the brakes, engine and diff before you stop. When you park, leave the car in gear and avoid using the handbrake (even though it is a drum brake system, within the rear discs).

Mostly, have fun and avoid any competitive red mist moments!

[PDJ]

It is your first time on a track and as no-one else has advised you to I will say book an instructor for the morning and the afternoon.

You can do a few laps on your own first thing to feel the car and you will probably be braking and turning in and applying the throttle pedal all in the wrong places but you will remember which way the track goes how long the straights are and the next corner left or right.

Now go out with the instructor anklet him/her guid you to make the improvements or adjustments to track driving.

Then practice on your own but remember practice make permanent (not perfect, perfect practice makes perfect)

Then go out with the instructor late in the afternoon to get some feedback on how you have improved (or not there is a lot to learn)

I used to track day my Westfield 255bhp and 510kg

Above all enjoy the day

[Kern47]

Cheers for the advice

I'll get the brake fluid changed to the ATE DOT 4 and look into pad options, thanks.

And I'm going with someone who's well used to track driving, so I'll take him along for advice, from what I gather blyton is a good beginner track without too much to hit, so might inspire some confidence to get the DSC off.

My plan is to get some track experience before having a go at Cadwell, which is only 30 mins from me, so itd be useful to be able to go there without too much fear of winning it.

But cheers again got the info I needed on the brakes

[Viren]

I hear you on brakes, definitely a weak point for hard track driven z4ms. However not something that always requires expensive bbk kits straight away.

1. Better pass (bluestuff work well and reasonable priced)
2. Dot 4.1 brake fluid
3. Cold air ducts/feeds, cheap to make and effective. Have a search in the forum, there are a couple of guides and how to make this

I run this set up and during 30c heat in summer last year at Bedford brakes lasted very well and wear was not excessive. Surprisingly I had less wear on the fronts (front had cold air ducts, rears did not), rears looked worse.

I'm sure eventually bbk may be needed however I'd rather put that money towards track days, tyres and brake pads for the time being.

[Mike.]

I hear you on brakes, definitely a weak point for hard track driven z4ms. However not something that always requires expensive bbk kits straight away.

1. Better pass (bluestuff work well and reasonable priced)
2. Dot 4.1 brake fluid
3. Cold air ducts/feeds, cheap to make and effective. Have a search in the forum, there are a couple of guides and how to make this

I run this set up and during 30c heat in summer last year at Bedford brakes lasted very well and wear was not excessive. Surprisingly I had less wear on the fronts (front had cold air ducts, rears did not), rears looked worse.

I'm sure eventually bbk may be needed however I'd rather put that money towards track days, tyres and brake pads for the time being.

I think you mean “Dot 5.1” but that doesn’t necessarily guarantee anything, I was sure that’s just a standard so you could have a good Dot 5.1 and an OEM Dot 5.1 which will differ in performance on track. Need to actually look at the detailed temp specs for the different brake fluids.

Were you running with DSC active while on track as that would explain the rear brake pad wear.

To the OP, brake judder is likely a caliper piston starting to stick so would sort this properly before tracking otherwise it could get so hot it seizes.

Like you’ve said, a full fluid renewal will see you right for a first go and just learn the car. An ATE Typ 200 brake fluid flush and a fresh fluids will be just fine

[BMWZ4MC]

....3. Cold air ducts/feeds, cheap to make and effective. Have a search in the forum, there are a couple of guides and how to make this....

Or just click on the link I posted

[Viren]

....3. Cold air ducts/feeds, cheap to make and effective. Have a search in the forum, there are a couple of guides and how to make this....

Or just click on the link I posted

yes or that!

[Viren]

I hear you on brakes, definitely a weak point for hard track driven z4ms. However not something that always requires expensive bbk kits straight away.

1. Better pass (bluestuff work well and reasonable priced)
2. Dot 4.1 brake fluid
3. Cold air ducts/feeds, cheap to make and effective. Have a search in the forum, there are a couple of guides and how to make this

I run this set up and during 30c heat in summer last year at Bedford brakes lasted very well and wear was not excessive. Surprisingly I had less wear on the fronts (front had cold air ducts, rears did not), rears looked worse.

I'm sure eventually bbk may be needed however I'd rather put that money towards track days, tyres and brake pads for the time being.

I think you mean “Dot 5.1” but that doesn’t necessarily guarantee anything, I was sure that’s just a standard so you could have a good Dot 5.1 and an OEM Dot 5.1 which will differ in performance on track. Need to actually look at the detailed temp specs for the different brake fluids.

Were you running with DSC active while on track as that would explain the rear brake pad wear.

To the OP, brake judder is likely a caliper piston starting to stick so would sort this properly before tracking otherwise it could get so hot it seizes.

Like you’ve said, a full fluid renewal will see you right for a first go and just learn the car. An ATE Typ 200 brake fluid flush and a fresh fluids will be just fine

Meant dot 4 ate typ200 same as you mentioned. Dsc was off but no rear brake cooling at that time. I've now added rear brake cooling so will see how it goes next week, although temps are low at the moment so difficult to compare.

[Ed Doe]

My advice from tracking my 3.0si is to change the fluid and leave everything else alone.

IF you really must, get some uprated pads, but in my experience lack of experience is the biggest factor to be improved upon and the only way to do that is with more trackdays

I found (albeit on Goodwood which is not overly heavy on brakes) the completely bone stock 3.0si brakes were sufficient for the first two ventures on track, and I only really upgraded for tart-factor
Obviously this will differ track to track, and based on driving style. One thing I would say though; a lot of people moan about the brakes 'going off', when in fact less experienced trackday goers tend to brake a little more like on a normal road drive - ie. hitting the brakes too early, and not hard enough. This has the effect of increasing the overall time per lap where you are putting heat into the brakes, and therefore obviously reduces the amount of time you are off the brakes giving them time to cool. The compound effect being the brakes do overheat.

TL:DR if you try to work out your braking points and hit the brakes late, hard and release promptly your brakes will last a lot longer and you'll likely not complain of fade Be like Tom_K

Also, brake judder on track - most often tends just to be pad deposit - ie. hit the brakes harder and it'll soon go

Either way just to echo a few others - go and have fun most of all, that's what it's all about! And try and get some videos! We all love a good trackday video