My E90 M3 Dedicated Track build (with pix!)

[roastbeef]

very nice lap, i love laguna. i'm sure the weather was fantastic. i want to say that your line is pretty much the line i was taking, but you're 9 seconds faster for some reason. at least i know i'm taking the right line i guess. nice driving. wish i could have made it. that track has been calling my name.

[redpriest]

Originally Posted by dogbone

My positive experience at Auto Club a couple weeks added another piece to the puzzle.

Originally Posted by dogbone

I decided I would drive Laguna DSC-off, and it worked out well. I have to say, coming out of the final turn (11) without traction was a revelation. Being able to get on the gas quicker is literally a kick in the pants! Jumping out of that corner in 2nd gear, the car takes off like a rocket. Very cool.

MDM will literally cut two seconds out of my life if I don't have the car absolutely perfectly lined up there - it pretty much solidified my desire to never drive with it on again (unless it was Sonoma + rain, lol).

Great driving, it's always entertaining to see how effortlessly you carve up the corners with 0 drama. Did you have the do88 DCT cooler mounted? How did it go? I just got mine put back on for Sonoma this weekend.

[dogbone]

Originally Posted by redpriest

Great driving, it's always entertaining to see how effortlessly you carve up the corners with 0 drama. Did you have the do88 DCT cooler mounted? How did it go? I just got mine put back on for Sonoma this weekend.

I have found that the fastest laps have the least drama. Drama usually means the car is going sideways. Sideways = slower in most cases.

No do88 cooler yet. The temp gauges have not been installed yet. First, I want to run with the stock cooler and a before-cooler temp gauge and an after-cooler temp gauge. Then we'll stick the do88 in so we can compare the performance between the two. I don't want a butt-dyno on this topic. I want to be able to track temps and really if there's a difference.

[Move Over]

Curious, where do you tie the front of your car down to your trailer. Does not look like the wheels? Let me know!

[dogbone]

Originally Posted by Move Over

Curious, where do you tie the front of your car down to your trailer. Does not look like the wheels? Let me know!

Hi.

It's tied on the front through the wheels.

I have hooks in the back. The hooks are tied into the rear subframe bolts. I got them from Rennline.

This is the rear hooks:


I would prefer some other solution for the front. And actually there IS a solution, but I haven't committed to using it. You can get "J" hooks that hook into the jack points on the bottom side of the car. So it requires permanently removing the jack pads on the bottom of the car. And then you cross the car with them so they sit in an X. My friend uses this method on his open trailer. It's VERY solid. From a time standpoint, I've compared it to just throwing straps through the wheels. I'm convinced that going through the wheels is still faster. My friend would argue with me. Anyway, I've been told that BMW ships the cars with the J-hooks, so I'm sure it's quite strong.

Here's what the J-hooks look like:


Other solutions like going over the top of the wheel don't work because the car is low and the tires are fat. Plus, with the splitter on the front sticking so far out and so low, it gets in the way.

I still have an emergency brake on my car. I kept it strictly for towing. So, I don't super slam my tie down straps super tight. I leave them with only mild tension. I don't like tugging hard on the wheels like that. My trailer is enclosed and the emergency brake is on (with the car in Neutral). The car is going no where.

[Move Over]

Originally Posted by dogbone

Hi.

It's tied on the front through the wheels.

I have hooks in the back. The hooks are tied into the rear subframe bolts. I got them from Rennline.

This is the rear hooks:


I would prefer some other solution for the front. And actually there IS a solution, but I haven't committed to using it. You can get "J" hooks that hook into the jack points on the bottom side of the car. So it requires permanently removing the jack pads on the bottom of the car. And then you cross the car with them so they sit in an X. My friend uses this method on his open trailer. It's VERY solid. From a time standpoint, I've compared it to just throwing straps through the wheels. I'm convinced that going through the wheels is still faster. My friend would argue with me. Anyway, I've been told that BMW ships the cars with the J-hooks, so I'm sure it's quite strong.

Here's what the J-hooks look like:


Other solutions like going over the top of the wheel don't work because the car is low and the tires are fat. Plus, with the splitter on the front sticking so far out and so low, it gets in the way.

I still have an emergency brake on my car. I kept it strictly for towing. So, I don't super slam my tie down straps super tight. I leave them with only mild tension. I don't like tugging hard on the wheels like that. My trailer is enclosed and the emergency brake is on (with the car in Neutral). The car is going no where.

Gotcha, thanks. Which hooks for the rear did you order from rennline? appears to be 66 degree.

I was thinking about maybe doing a 45 degree rennline hook, attached to the two rear corner 16mm bolts holding the metal belly pan on. Sheerly experimental.

I don't want to remove the jack pads in the front.

[dogbone]

Originally Posted by Move Over

Which hooks for the rear did you order from rennline? appears to be 66 degree.

I was thinking about maybe doing a 45 degree rennline hook, attached to the two rear corner 16mm bolts holding the metal belly pan on. Sheerly experimental.

I don't want to remove the jack pads in the front.

I believe they have a mild angle like 66 or something. I bought them several years ago…..

Yeah I didn't want to remove the jack pads either. That's another reason I haven't been using the J-hooks. My friend had to. His trailer is super short and there's not enough room from the back wheel to the trailer hooks behind them to tighten everything down properly. The J-hook solution is a necessity for him and works well.

Good luck with your experiment!

[leo95se]

at the sake of trying to catch up on this whole thread, what is your aero setup? the car has quite a nice build, though - nice work!

also, re: tires - have you tested an r-comp vs a slick? i didnt notice a substantial difference (under a second in a mostly street setup, which is made up for by longer life on r-comps). also note, my car isnt dialed in (all around solid bottom end, etc) where i would benefit from slicks.

[dogbone]

Originally Posted by leo95se

at the sake of trying to catch up on this whole thread, what is your aero setup? the car has quite a nice build, though - nice work!

also, re: tires - have you tested an r-comp vs a slick? i didnt notice a substantial difference (under a second in a mostly street setup, which is made up for by longer life on r-comps). also note, my car isnt dialed in (all around solid bottom end, etc) where i would benefit from slicks.

Hi.

(If you go to the First Post of this thread, I've committed to listing whatever is the current setup of the car with all aftermarket parts.)

Aero:
Wing: APR GT-250 67"
Lip: generic carbon lip that has a flat bottom good for attaching to a splitter
Splitter: APR Splitter (the carbon one, not the honeycomb one)

What's listed above has been on the car and driven for 9 months. All my latest personal bests have been driven with the above aero. I find that with the aero, I have been able to improve about 3-5 seconds at every track I visit. I'd say the average time improvement is around 3 seconds on a track that's around 2.75 miles.

Track: No aero PR/With Aero PR:
Buttonwillow 13CW: 1:54 MDM-on/1:49 DSC-off
Laguna Seca: 1:39 MDM-on/1:36 DSC-off
Auto Club: 1:53 MDM-on/1:46 DSC-off
Chuckwalla: 1:58 MDM-on/1:55 MDM-on
Big Willow Springs: 1:30 MDM-on/1:27 MDM-on

As far as tires, I have not tried Slicks yet. Until recently, I didn't feel I was a good enough driver to justify spending $2000 on slicks. Honestly, I didn't think I could push them hard enough and gain the proper benefit from them. Until 9 months ago, I drove mainly with MDM on. Aero really was the final factor that got me to turn traction control off because MDM just doesn't know what to do with aero and r-comps. Now, I've had 9 months to grow into the world of DSC-off, and I'm getting used to the feel of the car with aero on it, so I think a reasonable next step could be to explore the world of higher grip tires. The two tires I'm mainly considering are Hoosier A7 and Michelin slicks. Summertime at Southern California's tracks is very hot and not a good time to be experimenting with expensive grippy tires. So, in about 3 months, I'll probably start trying these higher grip tires in the cooler weather. I'm not really sure what to expect, but from talking to people who know about this stuff, I think I may be able to pickup 1-2 seconds.

Anyway, aero is really fantastic. I can't say enough nice things about how stable it makes the car feel. In a lot of ways, it sort of acts like traction control in the sense that a big ol' wing on the rear helps keep the rear in the rear! (I have a small modification coming soon to the aero. Stay tuned!)

[roastbeef]

What effect does MDM have when DSC is off?

[dogbone]

Originally Posted by roastbeef

What effect does MDM have when DSC is off?

DSC is the overall traction control system. MDM (M Dynamic Mode) is one of the setting options within the DSC system. If DSC is off, then there is no MDM.

There are 3 modes the car can be in:

-Traction Control Full-On: When you start the car, it defaults to full traction control On. It does not allow the car to go sideways hardly at all before it kicks in.
-MDM (M Dynamic Mode): In this mode, the computer will allow more vehicle slip angle than the Full-On version before it cuts power and engages individual brakes to regain control of the car. Within MDM, it was found that there was a "USA" version and "European" version. The European version simply allows even more slip angle than the default version in the USA. And even beyond that, you can even get more slip angle by changing some "WERT" settings. Someone has to code these European and WERT settings. You can't just change those in any of the car's menus.
-DSC-off: Traction control system is off. You're pretty much on your own, although the car continues to make sophisticated choices about how to activate the brake calipers when you press the brake pedal.

[roastbeef]

Originally Posted by dogbone

DSC is the overall traction control system. MDM (M Dynamic Mode) is one of the setting options within the DSC system. If DSC is off, then there is no MDM.

this is what i thought. i think i misread what you meant when relating your traction control mode to your personal bests.

[dogbone]

Originally Posted by roastbeef

this is what i thought. i think i misread what you meant when relating your traction control mode to your personal bests.

I always try to be very clear when it comes to my times and whether traction control was on or off because people get pretty crazy about this topic.

[dogbone]

I attended Global Time Attack at Big Willow on Saturday. Had fun. Did well. It was hot. No new personal bests, but I managed a 1:27.99 before the heat was 95ºF.

Anyway, I have a few things to update on the build, plus I had a tech issue while at the track.

I'll start with a pic of the sunrise on Saturday morning. Over the last several years, one of the little things that I have enjoyed seeing is the sunrises on my way to the track. The sunrise on Saturdaay morning did not disappoint.



Alright, enough gazing at nature. I have a couple minor new items on the build to report:

-Canards: Yay canards! hmmm…..flexible canards…..I bought AJ Hartman canards. They're fairly reasonably priced. They're carbon. They seem nice overall. They are fairly flexible once mounted though, so I think this install was just a first step. Casey at Racewerkz was talking about maybe running two metal rods through the outside edges in the front and back and having the metal rods tie into the splitter below to add some stiffness. I drove them on Saturday as pictured, and to be honest, I didn't feel anything. That's fine. I wasn't looking for miracles. The car drove great. I'm not complaining. I'm going to put a little more effort into the canards.



Canard side note: The Hartman canards have finished shiny carbon on top but they are rough and unfinished on the bottom and outside edges. I decided I wanted the carbon to look finished and coated everywhere. Racewerkz can handle that kind of thing. The canards are quite beautiful on both sides now. To be honest, it's probably not worth paying the labor to do it, but it's done now and they look great….Hopefully I won't mash these things off my car while putting the car in the trailer….

Here's before and after the carbon finishing:



-Transmission oil temp gauges: The journey of monitoring transmission temps has begun! I have mentioned before that ever since going traction control off and running R1S tires, the transmission has been the next component in the chain to overheat fairly quickly when pushing hard. Many people have installed aftermarket cooling pieces; some claim success, but others have seen dubious results. The problem is lack of data. Specifically regarding transmission oil temps, there's no ready-made easy way to monitor them. The AIM Solo DL can't track trans temps because AIM doesn't know the CAN ID address. The car definitely is able to track trans temps, but finding the CAN bus address has proven elusive. The Awron gauge seems to be the ONLY gauge that can track transmission oil temps off the CAN bus, but it doesn't do any data logging. I'm still holding out some hope that I'll be able to get the CAN bus ID. AIM said if I can get the ID, they'll incorporate the channel into the AIM Solo. If anyone out there has a line on this kind of information, let me know.

Even if the AIM could track that data, it's still after-the-fact info versus live in-car info. Yes yes, I know you can setup a page on the AIM to display realtime data, but the AIM always temporarily switches screens to show you lap times at the start/finish line. So, at the exact moment you want to know what your trans temps are, so you can decide if you can do another hot lap, it's showing lap times for like 10 seconds…….A dedicated gauge is the way to go.

Since I wanted hard data on how the DCT oil cooler works, first we had to install a gauge boss that has ports that allow temp gauges to be used. Macht Schnell makes a gauge boss with two temp ports so you can monitor temps of hot oil leaving the transmission and cooled oil coming back into the transmission. By placing the gauges right outside the transmission, we get to see the net effect of the whole DCT cooling system---the lines and the DCT radiator all working together as intended.

I bought two Stack gauges and wanted them placed somewhere on the dash that the in-car GoPro could easily see. Racewerkz built a nice carbon panel that sits in the iDrive screen slot. We made the hot oil gauge Red and the returning cooler oil gauge Blue. (I may change the blue to yellow or something…..so many color choices! )

I'm quite happy with this gauge setup. It's very easy to quickly glance at while on track, and the GoPro had no problem seeing the gauges. And it's cool to watch the gauges on the GoPro video because you can quickly scroll through the video and watch the needles move and see where the maximums are occurring and see how much cooling the coolers are doing.

From looking at the video from the 4 sessions I drove, when the system is hot mid-session, the stock cooling setup seems to cool the DCT oil temps around 20-25ºF. About the hottest DCT oil temps I saw were around 245ºF leaving the transmission. And the cooled returning oil would be in the 220ºF range around that time. The ambient air temps were around 92ºF.

I plan on leaving this setup for several track days. Then we will switch coolers to the do88 DCT cooler that we have ready to go. And then we'll see. No butt dyno! I want real data. If companies are going to make products like these, and charge over $1000, I want to see if they work any better than stock.








Tech Issue: a radiator hose sprang a small leak while on track in Session #3. I did not realize what it was, but I saw white water spotting on my hood. I thought somehow it came from my misting system (even though I use distilled water which leaves no marks at all). I drove Session #4 and the car drove fine, but when I brought it into the paddock, there was a hissing sound. I opened the engine bay and water was spraying from the hose. It kept hissing after the engine was off. Casey from Racewerkz was there and decided to alleviate the pressure. I would not have been that daring. We checked the water temps on the AIM, and they were higher than normal once the leak occurred but nothing damaging. By the time I shut the car off, the car still had not given me any warnings about radiator fluid levels. The next day as I moved it from the trailer, the car was warning that radiator levels were low. I'm not sure how much fluid is missing.

Anyway, this tech issue highlights something that has been bugging me for awhile: How do you find out when to preemptively replace parts on a race car so that you don't have breakdowns on track? I am not a race team and there is no tech staff monitoring the age of the parts in the car. This is my first track build. I'm learning as I go. I have actually asked around to several places if there are any general maintenance schedules that exist for tracked cars or race cars. Is there some kind of list that considers mileage or number of track days or number of hours run or how old the parts are that tells you what to preemptively replace so that you can avoid problems before they happen? The answer is always no. This is VERY frustrating to me. Why aren't there some lists with generic guidelines that give some general indication on how long they last? For instance, how long do rear axles go before you should replace them? Or how long should you run a wheel hub? Or how about the rubber belts? I don't know anything about brake master cylinders. How long do they last? How long do control arms last? I'm willing to replace stuff on a schedule since I run the parts hard, but I have had no luck in finding anything like that. Anyone have advice?

At some point, I guess my engine that currently has around 100 track days on it will just blow up. Is it worth trying to head that off at the pass before it happens? Or should I just wait and deal with it when it happens. Opening a healthy engine is not cheap. I priced it out. You're looking at $15k to pull an engine, open it all up and replace all the internals. These days, you can find a whole other engine with much less wear than mine for less than that. Honestly, no one ever thought I'd get this far with this setup---including me. So I feel like we're in somewhat unknown territory now with the engine.

But c'mon----control arms or axles or hubs or hoses or those kinds of things? There really aren't ANY accepted general standards for replacement for those kinds of things? The Porsche guys seem to have general schedules they follow on part replacement and rebuilds. Honestly, I've started my own list based on my track experience with brake seals on BBK, suspension rebuilds, suspension nitrogen maintenance, studs, rotors, belts, fluids---blower fluid, DCT oil, diff oil, motor oil, blower intercooler fluid, engine coolant, power steering fluid, blower air filter, spark plugs, now I'm thinking about hose life. Hey how long do fuel injectors last? Geez…..

[leo95se]

That's a great and loaded question. It depends on how far you want to take maintenance. Hoses aren't typically a problem with adequate inspection. Fluids should be annual (steering, coolant). Dct fluid I have no idea. No hard evidence. Some racers replace rod bearings annually. Some replace items like toe arms annually. I recently heard of a camber arm failing., so you never know..

[Richbot]

S65 blocks are valuable enough that pulling and replacing when something relatively important looks about to fail or during an off season seems smarter than running it until it goes kerblammo and ventilates the block. If I were you I would do a leak down test every half season and when the numbers start to drop, go ahead and rebuild. Leak down tests are cheap, easy, noninvasive, and good indicators of overall engine health from a topend/combustion chamber perspective and absent some sort of bearing/oiling issue should be the first place you see degradation in a track-only engine

Generally speaking, the "wtf is the design life for this part" question is why racecars get rebuilt ground up in off seasons or between races or even between 1/4 mile passes. The only good teacher is experience and that's something you get when something bad happens and it doesn't kill you...

But really, the only way to answer this question is pain either failures or preventive replacement money. At least with preventive you build a good inventory of known serviceable if aged spares

[dogbone]

Originally Posted by leo95se

Some replace items like toe arms annually. I recently heard of a camber arm failing., so you never know..

"You never know"-----that is what's so frustrating. It seems to me that this stuff is important enough to have at least some general guidelines. I mean is a control arm in a E9x M3 so different than other control arms in cars that have been around for decades that no one has a general idea how long they go before you should replace them?

I'll give you another example question: I've replaced my front driver-side hub twice due to broken studs in 4 years. The front right hub is still the original stock hub after all this time. The rear hubs are also original and have never been serviced. Uh, is it time? They still roll smoothly and have no play in them whatsoever……so, when is it time?

[dogbone]

Originally Posted by Richbot

S65 blocks are valuable enough that pulling and replacing when something relatively important looks about to fail or during an off season seems smarter than running it until it goes kerblammo and ventilates the block. If I were you I would do a leak down test every half season and when the numbers start to drop, go ahead and rebuild.

Generally speaking, the "wtf is the design life for this part" question is why racecars get rebuilt ground up in off seasons or between races or even between 1/4 mile passes. The only good teacher is experience and that's something you get when something bad happens and it doesn't kill you...

But really, the only way to answer this question is pain either failures or preventive replacement money. At least with preventive you build a good inventory of known serviceable if aged spares

Thanks for your advice. A leak down test sounds like a good place to start with the engine. I also get Blackstone reports and they've been very nominal.

I like the idea of having some spares lying around when you preemptively replace parts.

[roastbeef]

well, if you're starting to question suspension arm maintenance, have you considered full race links? i would imagine that solid or rebuildable links should take some of the guesswork out, right?

i recently had the front tension arm bushings replaced with monoballs. this week, i'm finally pulling the trigger on subframe/diff bushings. i'm enjoying doing everything separately because i get to feel and enjoy every little change by itself. i'm also sort of hoping another positive may be knowing how each suspension part makes the car feel. as my education and understanding of different parts of this car grows, i'm hoping in the future, i'm able to just be more knowledgeable about suspension and knowing what to change in the car if i run into settings i don't like. maybe i can also better feel when something is wrong or out of whack..

isn't the guesswork part of the fun?

[rcracin]

Experienced racers should be able to give advice. Some of it can be as basic as what a mechanic checks. For example:

Wheel Bearings - check play in wheels, the hub itself should last a lifetime, but as you said they've broken on you. That isn't something you can monitor for wear and tear, but the bearings are. For studs, I believe it's every season or every other season.
Camber Arms, Lower control Arms - Use a pry bar between the arm and subframe and see if there is any play. Usually if there is, you'll see a cracked or worn bushing. If using Sphericals, inspect for play or visible wear on the metal.
Rubber components like belts & hoses. I assume you'd be flushing coolant at least once a year before the season starts. Inspect the hoses and belts then. I'd replace every 2 years regardless. BUT, I would also keep spare belts and hoses in the trailer along with fluids.

A lot of other things like brake master cylinders and axles just need to be inspected. Generally, a brake master cylinder won't fail on you 100%. You would notice a softer pedal. But if it is failing, you can also see it in the color of your brake fluid. The seals will start to allow moisture and dirt to enter. For axles, inspect rubber boots. Axles fail when the boots tear and grease escapes.

For the motor, the leakdown tests is a must. Motors also get tired and make less power. If you can dyno it on the same dyno every year, you can probably notice when it starts to lose power. You definitely don't want to wait until it fails though. Blocks can be expensive. When you do rebuild the motor though, that's when you would get the injectors cleaned and flow tested.

I think i'm going to race karts instead of the m3. shit sounds like to much work lol

[dogbone]

Originally Posted by roastbeef

i'm enjoying doing everything separately because i get to feel and enjoy every little change by itself. i'm also sort of hoping another positive may be knowing how each suspension part makes the car feel. as my education and understanding of different parts of this car grows, i'm hoping in the future, i'm able to just be more knowledgeable about suspension and knowing what to change in the car if i run into settings i don't like. maybe i can also better feel when something is wrong or out of whack..

isn't the guesswork part of the fun?

Yeah, you and I have talked about doing changes one at a time and feeling the differences. That's what I did. I loved that.

As far as guesswork, I'm happy to do guesswork on settings. It's the technical maintenance that I don't want to be doing guesswork. At some point, especially as the car gets some solid wear and tear on it, you start get this odd feeling that something is about to go…..and you're just sitting wondering what thing it's going to be. My car is 7 years old now. It has some wear and tear on it…...

[Richbot]

At risk of starting a nerd fight, oil analysis, frankly, doesn't tell you jack about engine health, it can give you a true positive, but they also frequently give false negatives and false positives. Oil testing is for testing oil, if your blackstone reports look good you have chosen an oil and OCI that works for your application but that's about all you know

So yeah. Leakdown. Which is of course a super fun time on an 8cylinder engine with two cylinders buried under the dashboard, but hey, you asked