Z4 M Coupe mods, the ongoing tale...

Earl,

Wow, what a thread. As you know I only recently added the M coupe to my garage and am trying to learn more about it. I am not too interested in mods but I sure am learning a lot about the car from your post!

I also like your attitude with some of the negative comments.

Originally Posted by Palantirion

Saturday night I hurt my neck driving the car (pulled muscle). I took the car out for a "handling evaluation" after adjusting the tire pressures (31psi). The car is SICK! I actually made myself a little nauseous and after I parked the car at home I discovered that even after a short freeway drive back I was a little bit dizzy. My heart rate was nicely elevated too

Sounds like you're making progress! "I got out of the car with wobbly knees and felt like I stepped off a roller coaster" is a good thing!
Do you use a tire pyrometer at the track? As you play with the variables of camber and tire pressure, it's nice to collect some data to verify that you're doing the right thing...

Originally Posted by Fast6

Sounds like you're making progress! "I got out of the car with wobbly knees and felt like I stepped off a roller coaster" is a good thing!
Do you use a tire pyrometer at the track? As you play with the variables of camber and tire pressure, it's nice to collect some data to verify that you're doing the right thing...

-I have a pyrometer and intend to use it asap. I had it with me last time to the track, but because of the low ride height and intermitant rubbing I spent most of my pit time addressing that issue.

Update
I swapped pads today for my track days tomorrow and Sunday. I'm going with Perforance Friction Carbon Metallic race pads front and keeping the "stock" Axis rear. Hopefully there will be no issue with the change in friction bias...we'll see...

I also updated my seatbelt guides as per grnrcr's suggestion:
[IMG]http://ebsart.com/images/Net%20Publication/Misc%20Scatha/Mod%2028.JPG[/IMG]


It looks much better than my initial bolt/washer fix. The only problem is that the seatbelt doesn't retract as well because the CG-Lock's added weight "weakens" the return spring tension.

Nice work done to your car Keep it coming!

Update
Round 1 at Cal Speedway went flawlessly yesterday - IE: No walls were hit Unfortunately my wife was working so I didn't have a photographer to shoot pics. A buddy of another driver tried to get some with my camera during my second run, but he only took one and it was from very far away. My wife should be with me Sunday so expect some decent shots

The NASCAR banking is very intimidating and the Gs can be downright uncomfortable. By the end of the day I was peaking at 8k in 4th (145mph) just before turn 1, turning in at about 140mph and carrying 135mph through the turn if I caught the right groove.

The PF pads worked pretty well once they were fully bedded. Meaning that the car stopped much quicker than with the Axis street pads, but the brake balance was somewhat effected by dissimilar f/r pad material. The car nosedived more as the rear wasn't equalizing the braking forces. This did not translate to any significant stability problems, but didn't boost my confidence either.

Today I took the car down to BMS and put on the Hawk HT-14 and HT-10 pads that hadn't arrived in time for Friday's HPDE. My only experience so far has been bedding them in, but the car feels much more planted - squatting on all fours instead of pitching forward. We also cut out the factory air plugs so there should be a little more airflow around the brakes. I'm quite exited to drive tomorrow!

p.s. After examining vids I shot with my little camera sticky-podded to the Coupe's roof my lap time in the 4th session was around 2:00 to 2:01. My fastest lap was 1:59.

Originally Posted by Palantirion

Update
Round 1 at Cal Speedway went flawlessly yesterday - IE: No walls were hit Unfortunately my wife was working so I didn't have a photographer to shoot pics. A buddy of another driver tried to get some with my camera during my second run, but he only took one and it was from very far away. My wife should be with me Sunday so expect some decent shots

The NASCAR banking is very intimidating and the Gs can be downright uncomfortable. By the end of the day I was peaking at 8k in 4th (145mph) just before turn 1, turning in at about 140mph and carrying 135mph through the turn if I caught the right groove.

The PF pads worked pretty well once they were fully bedded. Meaning that the car stopped much quicker than with the Axis street pads, but the brake balance was somewhat effected by dissimilar f/r pad material. The car nosedived more as the rear wasn't equalizing the braking forces. This did not translate to any significant stability problems, but didn't boost my confidence either.

Today I took the car down to BMS and put on the Hawk HT-14 and HT-10 pads that hadn't arrived in time for Friday's HPDE. My only experience so far has been bedding them in, but the car feels much more planted - squatting on all fours instead of pitching forward. We also cut out the factory air plugs so there should be a little more airflow around the brakes. I'm quite exited to drive tomorrow!

p.s. After examining vids I shot with my little camera sticky-podded to the Coupe's roof my lap time in the 4th session was around 2:00 to 2:01. My fastest lap was 1:59.

Sounds like you're having a blast out there; wish I could have made it, but there's been a lot of activity on my project Mustangs this week, so Friday was spent bouncing between shops, moving parts around and prepping my garage for braking apart a 289 from its tranny, which encompassed most of my day yesterday.

Anyway, you went with the HT-14's, huh? Sounds like a really agressive setup. What's the noise like? I assume you're going back to the Axxis street pads for day to day driving?

Originally Posted by PPG4

Sounds like you're having a blast out there; wish I could have made it, but there's been a lot of activity on my project Mustangs this week, so Friday was spent bouncing between shops, moving parts around and prepping my garage for braking apart a 289 from its tranny, which encompassed most of my day yesterday.

Anyway, you went with the HT-14's, huh? Sounds like a really agressive setup. What's the noise like? I assume you're going back to the Axxis street pads for day to day driving?

-The noise isn't too bad. Some squeal under light braking, but not as bad as I expected. With medium or hard use there's no noise. Definately having a blast!

Update
Here are my pics from this weekend's HPDE at Cal Speedway. The Coupe behaved fabulously and once again confirmed that it is the right car for me Speed Ventures was a great organization to run with. They are very perceptive and professional. They don't offer the degree of driver education as Driving Concepts, but are much less expensive and offer the same amount of track time.

Pics of the paddock area:
Friday there were a lot of Corvettes...and most of them were track or race-prepped:


This Z06 was mean looking, although I was faster until he learned the track better. It still amazes me how a low-powered car can keep up with a more powerful car in the straights just from cutting a better line.


My Coupe parked on Sunday:


I never saw this Ferrari on track. I guess he wasn't fast enough to lap me, and I certainly wasn't fast enough to lap him:


This C5 was supercharged and was putting more than 700hp to the rear wheels. The Coupe was still slightly faster around the track however, as he had trouble putting all that power down and even with slicks the C5 is not a great-handling car:


Another David vs. Goliath story was this Shelby GT 500. With 550hp it was still a LOT slower around the track than my Coupe. Props to the guy for bringing it out though! I'd much rather see it getting wrung out than sitting in a garage


More cars in the paddock:




I watched one of the POC races. It was fun. There were good battles for 1st and 3rd.




Continued in the next post...

...continued from the last post...

Pics of my Coupe:
On the front straight:


On the banking at about 130mph:


In turn 5:


Chasing a Lotus through turn 11:


Going through turn 12:


Some pics of the Coupe at turn 13. If you look closely you will see my roof-mounted camera system:








Turn 15:


Turn 18:


Crossing Start/Finish:


Those aren't bugs, that's all road tar from the track


My front right RA-1, still with some life left in it. Note the paint marks to check for fender rub (no rub, with the most recent ride height adjustment):


I took video (from the roof camera) but can't edit it without my computer crashing. So I'll try to get it over to my laptop and edit it down so I can publish it...

Sweet pics, suprised to see the Elise's lean more than the MC in the turns.

Originally Posted by Palantirion

I took video (from the roof camera) but can't edit it without my computer crashing. So I'll try to get it over to my laptop and edit it down so I can publish it...

Can't wait to see the video. I was just there on Monday with DCI. Did you guys run with a chicane on the front straight to turn "2" transition?

Originally Posted by z3power

Sweet pics, suprised to see the Elise's lean more than the MC in the turns.

They're pretty softly sprung. Surprised me too the first time I saw one in action. It's all about the balance...

Originally Posted by z3power

Sweet pics, suprised to see the Elise's lean more than the MC in the turns.

FWIW, all taken from nearly the same spot at last Sunday's autoX

Elise





Z4MC with stock suspension (and not driven all that aggressively)


Z4MC H&R sport springs (driven aggressively but not all that competively )


I think the first photo is the only one I took. The blue Elise and I were in the same run group and I was working when the other Z4MC was running. I let a friend who was not running use my camera to capture the 2nd and 3rd run groups.

Originally Posted by z3power

Sweet pics, suprised to see the Elise's lean more than the MC in the turns.

Originally Posted by Fast6

They're pretty softly sprung. Surprised me too the first time I saw one in action. It's all about the balance...

-Bear in mind I'm running 500lb front and 600lb rear springs, while the Elises were stock. Regarding balance, both Lotus owners I spoke with had a lot of trouble with turn 11 (the "buttonhook". It's a decreasing radius turn entered aroung 100mph and apexing around 40mph (I think). They said their problem was that if they didn't stay a little on the gas, the Lotus' rear would swing around immediately. But if they did stay on the gas at all, they were fighting understeer through the whole turn. Honestly, it sounds to me like the classic 911 problem, only moerso. Given the math of their weight distribution I'm not surprised.

Originally Posted by The HACK

Can't wait to see the video. I was just there on Monday with DCI. Did you guys run with a chicane on the front straight to turn "2" transition?

-We ran the proper race ROVAL - no chicane. I've run with the turn 1 chicane before and it's very fun because of the elevation change, but I chose this event specifically because I wanted to run on the real race course and experience banking. Did DC run with a chicane?

Originally Posted by Cliff

FWIW, all taken from nearly the same spot at last Sunday's autoX

-Cliff, those image links didn't work at first, but then they did after a refresh - weird! Anyway, great pics. The Lotuses sure do lean, even more than a stock MC, which is saying a lot!

Originally Posted by Palantirion

-We ran the proper race ROVAL - no chicane. I've run with the turn 1 chicane before and it's very fun because of the elevation change, but I chose this event specifically because I wanted to run on the real race course and experience banking. Did DC run with a chicane?

Chicane. Given the hardware we had at the track and what happened 3 years ago at the speedway, running sans the chicane would have been suicide.

Sans the chicane we have several cars at the track that can easily reach in excess of 180mph. By my quick calculation, we had in excess of 10,000 hp at the track.

Originally Posted by The HACK

Chicane. Given the hardware we had at the track and what happened 3 years ago at the speedway, running sans the chicane would have been suicide.

Sans the chicane we have several cars at the track that can easily reach in excess of 180mph. By my quick calculation, we had in excess of 10,000 hp at the track.

-The chicane had nothing to do with the specifics of the infamous accident. It happened on the infield straight - the front straight wasn't even in use that day. SV had several cars in the 600+ hp range too and had no incidences on the banking (even with open passing). Safety really comes down to a driver's judgement and training - in that priority! I understand why DC would want to decrease the potential for serious accidents by running with the chicane, and they know their clients' skills well enough to judge. But I wouldn't go blaming the "hardware", or refering to sans chicane as "suicide". It isn't, regardless of the car in question. It's simply a matter of judgement and training.

Here is my fastest lap of the weekend, 1:59.20. It's definately not perfect, and I welcome discussion if anyone wants to analyze it with me. (p.s. This may get taken down in the near future for hosting space reasons, so d/l it now if you want it on file.)
VIDEO

Originally Posted by Palantirion

-The chicane had nothing to do with the specifics of the infamous accident. It happened on the infield straight - the front straight wasn't even in use that day. SV had several cars in the 600+ hp range too and had no incidences on the banking (even with open passing). Safety really comes down to a driver's judgement and training - in that priority! I understand why DC would want to decrease the potential for serious accidents by running with the chicane, and they know their clients' skills well enough to judge. But I wouldn't go blaming the "hardware", or refering to sans chicane as "suicide". It isn't, regardless of the car in question. It's simply a matter of judgement and training.

Here is my fastest lap of the weekend, 1:59.20. It's definately not perfect, and I welcome discussion if anyone wants to analyze it with me. (p.s. This may get taken down in the near future for hosting space reasons, so d/l it now if you want it on file.)
VIDEO

I was being my usual overly dramatic self with the "suicide" comment. By the end of the day almost all the cones were knocked down, so when I had a chance to go drive my one session I didn't bother slowing down too much for the chicane anyway. I actually got a little motion sick (which I NEVER had) the first half of the day and was only able to hot-lap for about 8 laps.

There's too much wind noise so I can't tell when you're applying throttle, and the camera position makes it impossible to see hands, so I can only comment on the line. What you may want to try the next time you're there, is on turn 2, when you past about the half way mark (you'll see it on the video as you pass the "2" on your right hand side) you can dial in a little bit more turn and let the banking of the turn shoot you straight to your braking zone. You can pick up a lot more speed this way. You need to get to the bottom of the banking where the grass meets the concrete (but don't use the concrete inside the white line where there's no bank). Especially on R-comps, that drop on the banking and straightening out the last half of the turn let's you get on the throttle much MUCH harder for that last portion before you have to hit the brakes. It's not the safest line so be careful, as it requires straightening the car out just prior to getting to your braking zone, as oppose to actually having the comfort of having the car straight for quite a few seconds before getting to your braking zone. But I've experimented with both lines and have found that I'm about 5-10mph faster.

Turn 5...Try double apexing that turn. Make the line shorter, throttle steer mid turn. At 3,200 lbs the MZ4 Coupe is just light enough to make that line work. You'll probably go through the turn at the same speed, but the double apex line makes for a shorter "curve." E46 M3s, 5 or 6 series I would probably take that wider line you took. Looks like you've done the Speedway in a heavier car and got used to the heavier car's line.

Other than that, I'm not sure what else I can suggest for a faster line. I wonder if you've tried getting to the top of the bank on the front straight before getting to turn 2? I've gotten so used to driving it with the chicane that I always get to the top of the bank by the time I cross start-finish.

Hey Folks, new to this board (my first post)...I've read through this entire thread, probably one of the best I've seen on any of the boards I frequent. That being said, has anyone compiled a relatively comprehensive list of what performance mods are currently available for the Z4 M Coupe.

I recently picked up an '06 with ~2K on the clock and am looking to make some changes. the items I've been able to find (but not neccessarily items I would choose) so far are:

UUC Short Shift
UUC Clutch/Flywheel
Dinan 3.91 (local shop has a 4.10 as well)
Ubiquitous CDV removal
SuperSprint Exhaust
I'm sure there's a K&N for the car

Anyone have any others or know of one spot to find a list?

Thanks...looking forward to the feedback.

Originally Posted by The HACK

There's too much wind noise so I can't tell when you're applying throttle, and the camera position makes it impossible to see hands, so I can only comment on the line.

-Yeah, it's hard to hear the throttle even in the car. It's very quiet. I've tried to shoot vid inside the car before, but with my little pocket camera I have no way of setting the white balance so it defaults to the car's interior. The end result is that you get great shots of my hands on the wheel, but can't see the track I'm going to be getting a proper camera/telemetry setup this summer.

Originally Posted by The HACK

What you may want to try the next time you're there, is on turn 2, when you past about the half way mark (you'll see it on the video as you pass the "2" on your right hand side) you can dial in a little bit more turn and let the banking of the turn shoot you straight to your braking zone. You can pick up a lot more speed this way. You need to get to the bottom of the banking where the grass meets the concrete (but don't use the concrete inside the white line where there's no bank). Especially on R-comps, that drop on the banking and straightening out the last half of the turn let's you get on the throttle much MUCH harder for that last portion before you have to hit the brakes. It's not the safest line so be careful, as it requires straightening the car out just prior to getting to your braking zone, as oppose to actually having the comfort of having the car straight for quite a few seconds before getting to your braking zone. But I've experimented with both lines and have found that I'm about 5-10mph faster.

-That's the line I started with, and the line used by most of the other drivers. It may well be faster, I'm not sure yet. What I do know is that taking the higher line I can carry a lot more speed (135mph vs 120mph mid-corner) and still power out. Every time I was behind someone and they went low I either passed them or closed distance on them. Of course, being on the banking for the first time I was not about to push the car. It's possible that if I was willing to really push the car using both lines that the hi-low line would be faster. Or maybe not - the Coupe is really more of a momentum car. I'll make it a point to find out next time I'm there. Actually...I'll go back through my vids and see if I can accurately time the corner using when I was using both techniques...

Originally Posted by The HACK

Turn 5...Try double apexing that turn. Make the line shorter, throttle steer mid turn. At 3,200 lbs the MZ4 Coupe is just light enough to make that line work. You'll probably go through the turn at the same speed, but the double apex line makes for a shorter "curve." E46 M3s, 5 or 6 series I would probably take that wider line you took. Looks like you've done the Speedway in a heavier car and got used to the heavier car's line.

-I did, the MC hates double-apex on that turn. My M5 liked the double apex line a lot, but it's a point-and-shoot car due to its weight and torque. When I tried it in the Coupe starting rotation at 5A was easy with a little trail brake (same as for single-apex), but maintaining rotation with throttle was difficult on the tighter line. It just seemed like either the front tires would push or the rears would slip too much. It's possible that this could have been partly due to the fact that most of the other cars ran the single-apex line, so the double-apex line had less rubber on it and was not as warm. The other thing I found out about the double-apex line is that I track out at a slower speed (and at a weaker part of the S54 powerband) and consequently have less acceleration and speed down the following straight. Next time I'm there I'll try it both ways again. It could be the little variables that change the corner.

Originally Posted by The HACK

Other than that, I'm not sure what else I can suggest for a faster line. I wonder if you've tried getting to the top of the bank on the front straight before getting to turn 2? I've gotten so used to driving it with the chicane that I always get to the top of the bank by the time I cross start-finish.

-I was concerned about marbles (especially with so many running a low line), so I limited my banking excursions to the "4th lane" as I call it for turn-in and no higher than the "3rd lane" in-turn.

-Any suggestions for the last complex (turn 13+)? I never felt like I found a groove through there.

Originally Posted by Luminor

Hey Folks, new to this board (my first post)...I've read through this entire thread, probably one of the best I've seen on any of the boards I frequent. That being said, has anyone compiled a relatively comprehensive list of what performance mods are currently available for the Z4 M Coupe.

I recently picked up an '06 with ~2K on the clock and am looking to make some changes. the items I've been able to find (but not neccessarily items I would choose) so far are:

UUC Short Shift
UUC Clutch/Flywheel
Dinan 3.91 (local shop has a 4.10 as well)
Ubiquitous CDV removal
SuperSprint Exhaust
I'm sure there's a K&N for the car

Anyone have any others or know of one spot to find a list?

Thanks...looking forward to the feedback.

-I've got a list of my mods, but it would take more time than I have to list every possible mod. Also, we're still not sure about certain products - one's that work for an E46 and "should" fit. Time will tell. Probably a better strategy for you would be to figure out what you want the car to do differently and then see what products/advice can help you attain that goal.

Originally Posted by Palantirion

-The chicane had nothing to do with the specifics of the infamous accident. It happened on the infield straight - the front straight wasn't even in use that day. SV had several cars in the 600+ hp range too and had no incidences on the banking (even with open passing). Safety really comes down to a driver's judgement and training - in that priority! I understand why DC would want to decrease the potential for serious accidents by running with the chicane, and they know their clients' skills well enough to judge. But I wouldn't go blaming the "hardware", or refering to sans chicane as "suicide". It isn't, regardless of the car in question. It's simply a matter of judgement and training.

Here is my fastest lap of the weekend, 1:59.20. It's definately not perfect, and I welcome discussion if anyone wants to analyze it with me. (note: This may get taken down in the near future for hosting space reasons, so d/l it now if you want it on file.)
VIDEO

p.s. If I did the math correctly, 1:59.20 is 84.85 average mph.

[QUOTE/]-I've got a list of my mods, but it would take more time than I have to list every possible mod. Also, we're still not sure about certain products - one's that work for an E46 and "should" fit. Time will tell. Probably a better strategy for you would be to figure out what you want the car to do differently and then see what products/advice can help you attain that goal.[/quote]

Thank you for the reply. Your suggestion is as reasonable as it is obvious. I do have some idea of what I'd like the car to do differently, I was simply hoping someone might be able to add to the list of performance options I wrote down in the event one of them might be of interest. Given the relatively few options available I was hoping someone might be able to fire off a few that I wasn't aware of.

I'll ask a few specific questions:

Are there any other exhaust options outside of SuperSprint?
Does anyone know if there is an Alcon Brake kit available for our cars?
Is it worth getting the UUC short shifter (at $350) or is the Dinan shifter worth waiting on?
Are there any other clutch/flywheel options other then UUC?
Does anyone have any experience with 19" Neez wheels on the M Coupe?
I've heard some mention of Motons being applied to the M Coupe, anyone else seen/heard this?

Thanks again.

Originally Posted by Luminor

I'll ask a few specific questions:

Are there any other exhaust options outside of SuperSprint?
Does anyone know if there is an Alcon Brake kit available for our cars?
Is it worth getting the UUC short shifter (at $350) or is the Dinan shifter worth waiting on?
Are there any other clutch/flywheel options other then UUC?
Does anyone have any experience with 19" Neez wheels on the M Coupe?
I've heard some mention of Motons being applied to the M Coupe, anyone else seen/heard this?

Thanks again.

1) Not yet. BMS is working on one for my Coupe. I expect that by the end of summer (at the latest) it will be a viable option.
2) No idea, but I wouldn't go with Alcon over StopTech, Brembo or PFC. If you want to upgrade your brakes for cheap, swap the pads and put in stainless lines.
3) I really like the stock shifter, so I haven't researched any Z4 alternatives.
4) Not I.
5) We considered several of Moton's products but opted for TCK's because they are less expensive than Motons, easier to install, and are the valving is already optimized for the MC. SteveHiFi may be going with Moton Club Sports.

Originally Posted by Palantirion

1) Not yet. BMS is working on one for my Coupe. I expect that by the end of summer (at the latest) it will be a viable option.

Eisenmann too has exhaust


http://www.eisenhaus.com/ehdetails.p...57&Submit.y=14

Originally Posted by Caddyshk

Eisenmann too has exhaust


http://www.eisenhaus.com/ehdetails.p...57&Submit.y=14

I looked at the Eisenhaus (I'm considering getting a set of Neez wheels from them), but their exhaust, for the time being is just the muffler...not a full exhaust or even a cat back.