Jump to content
SpaceRangerJoe

She told me not to do it. A BMW story.

Recommended Posts

All the lights/blinkers are working now. Except the dash lights, but those aren't a super high priority. And the relay/speed control for the cool shirt. And probably all the other busted electrical in this thing. I don't wanna talk about it.

After looking at the crazy bleeder valve and getting some other opinions, I feel confident I know what was going on. The caliper was a rebuilt one I got form turner several years ago. It appears there was some problem with the bleeder valve in its former life, and the hole had been drilled, tapped, and some sort of collar put in there. An OEM bleeder was then installed in that collar. Of course that collar should have never come out, but it seized to the bleeder.

A new (rebuilt) caliper showed up yesterday. I got the brass bushings moved over from the old caliper and got it installed on the car. Then I pulled all the other calipers and cleaned/greased the bushings/sliders with high temp grease. Bled the brakes again, which was super easy when everything worked properly. Drove it up the street and the brakes seemed to work. I think that was my last item to be ready for the track this coming weekend. Woop!

Share this post


Link to post

The car did pretty well this past weekend. With all the rain Saturday, I bailed to see some family that was in town. If I had known for sure the rain would stop and the track would go hot(ish) I would have waited. Oh well. Sunday was beautiful though. The car felt great and it was good to finally get back on track. The RE71s seemed to hold up well. I ran two sessions with only a very short break in the afternoon (ran yellow, 20 min break, then ran in red). I could definitely feel the extra heat in the tires, but overall they felt good. I got very little audible feedback, but maybe my car is just loud :shrug:.

I did have a couple issues with the brake. I didn't notice any fade, but sometimes on the first press the pedal would have a lot of extra travel. If I released and hit them again it would bite with much less pedal travel. I've heard of people talk about this with pad knockback, but I've never experienced with this car before. I'm going to bleed the brakes a bit to see if any other bubbles come out but I don't think that's the issue. It did lead to a nice little off track excursion at horse shoe (twice...). I definitely didn't push as hard as I did in the past but I'm sure the confidence will come back to me with some more seat time.

I also need to look into a different steering wheel or hub extension. I forgot how far back and down you are when you're fully strapped in and I end up with more arm extension than I'd like. Not a super high priority though.

Share this post


Link to post

Been pretty busy, not not much has changed with the car. Got the coolshirt system rewired before the TDE event last weekend. It was hot, so that was definitely nice to have. The car did well, no issues at all. I still feel like I'm getting a little bit of pad knockback or something. The first press of the brake will be a but soft sometimes. I got in the habbit of giving it a little tap before the faster brake zones, and didn't have any issues.

I took about 2 seconds off of my best time from the event in April. I looked at the data a bit last night, and my fast lap (1:24.84 via AIM Solo) was all my best sectors, until the very last one. I somehow lost 2/10ths in the rattlesnake exit to the start/finish timing loop. That seems like a whole lot of time for that turn. According to the data, the previous lap to my best had the best final sector.

Tires have been my big concern, since I always went through them so quickly before. I have 3 days on these RE71Rs now, and they still have tread, so that's an improvement. They handle lots of slip pretty well. There was some decent drifting this weekend when I pushed too far, but it was still controllable. The shoulders look pretty good, but the inside half definitely has more tread left than the outside half. I'll try to get them flipped left-right before the next event. I did swap front to back wheels/tires Sunday morning. The fronts took a bit more of a beating than the rears. Are there secrets to driving fast while still maintaining tire life? If so, I should figure that out someday. As things stand now, I'm still renting a truck/trailer to tow it out. I should just get some slicks and send it. Might be fun.

No real changes planned. I may try to pick up a different camera for in car. I've been borrowing a GoPro3, but I think it would be fun to have a forward and rear facing camera. I may grab some newer off brand camera for forward facing, and make the gopro rear. Something with a remote that I can stick on the dash. Once I'm belted in, I can't reach the buttons, so I end up burning 5-10 minutes of camera time just sitting at the grid.

Share this post


Link to post

Pad knock back is definitely a thing.  I had it with the stock brakes in both my E36 and E46 M3's.  I think a light 'left foot' brush of brake before a turn is the ticket.  Or just upgrade the fronts to a BBK and not have to worry about it.  😉

Share this post


Link to post
10 hours ago, rickyboycz said:

Pad knock back is definitely a thing.  I had it with the stock brakes in both my E36 and E46 M3's.  I think a light 'left foot' brush of brake before a turn is the ticket.  Or just upgrade the fronts to a BBK and not have to worry about it.  😉

On every race car ever, esp. on tracks with gators.

Just add the original disc brake hardware (little springs etc) if you don’t feel like left foot tapping before heavy zones.

Share this post


Link to post

Pad knockback was really bad with stoptechs on my 350z. I switched to factory brembos and it lessened a bunch. Then I put in new front hubs and it all but went away. I ended up using pad knockback as a sign of worn hubs. YMMV.

Share this post


Link to post
On 6/13/2019 at 9:23 AM, SpaceRangerJoe said:

 Are there secrets to driving fast while still maintaining tire life? If so, I should figure that out someday. As things stand now, I'm still renting a truck/trailer to tow it out. I should just get some slicks and send it. Might be fun.

Get something other than re71rs.  They don't last, that's well known about them.  Look into RR's, RC1's, RS4's, etc. 

Share this post


Link to post
24 minutes ago, tyhackman15 said:

 Look into RC1s. 

Wear like iron, don't seem to heat cycle out until the tread is about cashed. At least for me. And not $$$$

Share this post


Link to post

I can get at least one more weekend out of these tires for sure, hopefully a bit more. I'll likely try RS4s or RC1s next. The prices for those seem pretty darn close unless one of them goes on sale soon. If I decide to plan ahead (for once) I'll bring the new set of something with me and just roll with the RE71s until I see cord.

56 minutes ago, Dave said:

pad knockback as a sign of worn hubs

Not related to the knock back issue, but I've wondered about this. I've never replaced the hubs on this while I've had it. It doesn't seem to be a common issue on these cars as far as I can tell, but I know I'll need to do it someday. When I pull the wheels to clean and inspect, I'll poke around on the hubs to see how they feel.

Share this post


Link to post

RS4s are iron, love them more than the RS3 before it. At race pace they were lasting an entire weekend (16 hours) on a WRL Miata. They don’t overheat, go greasy, etc. Squishy side wall and grip for days. Just bullshit figures here but I’d say they’re  around a second off RE71R pace (which are just ungodly for a 200tw) but last four times as long.

Share this post


Link to post

Meant to say if this is also driven on the street, or to the track, it’s the go to over the RC1 (which is an incredible track compound for the price and life of it).

Share this post


Link to post

Since I'm towing the car for at least the rest of the year, I'll probably try to grab a set of RC1s. I haven't found the size I want in stock anywhere (235/40-17).

In someone elses video, it looked like I had no brake lights. I checked those, and everything works, I guess the old lights just aren't as bright as new LEDs (shocking). I found the risers for the rear wing in a box, so I'll try to get those thrown in this weekend. I'm sure there is no aerodynamic benefit to it at all, but I like the way it looks so I'm doing it. It could use a nut/bolt check to make sure everything is solid. Other than that, washing it is the only thing on my list.

I spent a little more time looking at data. @Dave sent me some data from one of his fast laps for me to compare. The consistent theme is I brake too early it seems. Braking force (looking at G's) is pretty close. Mid corner speed and lateral acceleration are close in most areas, but I can see myself overslowing in a few places. I brake earlier, slow too much, get back on the gas a bit mid corner, then hold maintenance before hitting the power out. I think not overslowing would be a good place to work on for now.

I was way off on my theoretical best lap too. I made some mistakes on my lap selection, so the data was bad. Data now shows a 1:23.15 for a theoretical best, so plenty of room for improvement. Driving cars is fun and I wish I could do more of it.

Share this post


Link to post

I did a small brake flush yesterday when I got home. I don't expect it will make a difference in the pad knock back issue I think I was getting, but it won't hurt. Didn't see any bubbles come out, so that was good. Checked and topped off the oil too. I need to order some new filters and I'll toss one in there soon. I chickened out on the RC1s after seeing people talk about them not handling high ambient temps very well (Texas summers, lol). I ordered some RS4s in 255/40-17 last Friday. They were at the door today.

tires.thumb.jpeg.80a4dd30baaef154824e41365043942f.jpeg

These will be the backups in case I cord the RE71s, which are being flipped on the wheels. Maybe I should add some more camber back to the front. I'll see how things go this weekend.

I also found the risers for the rear spoiler, so obviously I added those back. It looks like they add a little bit more angle as well. I'm sure any added down force (lol) can't possibly be worth more than the drag this adds, but I like how it looks so whatever.

risers.thumb.jpeg.09ce162f4c833596c882f93d923fd5e5.jpeg

When I get wheels and tires back on I'll get it washed, which it needs terribly. It's probably been 3+ years since that's happened. The sunroof replacement panel needs to come out sometime, but it won't happen before this weekend. I need to get the last of the plastidip off, then repaint and seal it. I didn't do a great job last time.

Pretty much ready for TDE this weekend at Cresson. Gonna be warm out there, but the coolshirt is ready to go.

Share this post


Link to post

Temp on the car were awesome, even in the heat. Coolant max was 205, Oil max was 222. I had some issues with understeer on Saturday. I tried higher and lower tire pressures with no noticeable difference. Then I did what I should have done sooner and asked someone who knows about car setup what to change. Adam at Doghouse had several suggestions. I softened up the front dampers a bit (single adjustable konis). Things seemed a little better, but not a ton. I rolled down to Doghouse again and Adam threw it on the lift to soften the front sway bar. This helped a bit more, but I still couldn't get the throttle rotation I wanted. I stiffened the rear dampers, and all of a sudden I had some throttle rotation back. I really had to work on some self control and finesse this weekend. Without a ton of HP, I can really just mash the throttle in a lot of instances. This weekend that would just cause the front to start pushing, particularly in places like wagon wheel and horse shoe. I had to hold my maintenance a bit longer and roll into the throttle, then things were better. A friend of mine came out Saturday to go for a ride. He made it through 8 laps before he thought he was going to get sick so I feel like I did my job on that one.

Oil consumption seemed pretty standard. I probably added 2 quarts this weekend which is normal. Tires are pretty low, but I do have 5 days on them now. Their fast days are behind them, but I have the RS4s ready to go so I'll run these to the cords. I had some strong shuddering under hard braking which is a new development. I'll measure the rotors, but I'm pretty sure these are the ones I put on there when I got the car so I'd feel fine replacing them. The carbotech pads still have plenty of meat left.

When I was pulling the car off the trailer Sunday evening, I didn't realize the front lip had caught so it nearly ripped the bumper off. The mount for the Motion Motorsports undertray got all bent up and ripped out one side. That put me in a super great mood. I can probably bend it all back and remount everything. I don't have a weekend at home for at least a few weeks, but I'll get around to it some day. The pictures are after I pulled on things a bit to stop it from rubbing on the tires so I could get it in the garage.

IMG_0711.thumb.JPG.8e885077e262bb8a4ce712ce5c18070a.JPGIMG_0710.thumb.JPG.f8bfd87aad96d8f8498c88555a6cdbdf.JPGIMG_0709.thumb.JPG.9ac6303d985bf3e18f3fe4445b18a75a.JPG

Share this post


Link to post

I had a few minutes last Wednesday after work, so I got the bumper pulled off to check out the damage. It really doesn't look bad. A little bit of bent metal that I think I can hammer back into shape, and some new rivnuts, then I should be good to go. The much thicker under tray is totally fine, it's just the vertical mounts that bent. It looks like a plastic clip or two got trashed, but NBD. I may be at home next weekend, so hopefully I can get everything put back together. That give me time to order some parts I need, like brake rotors and the brake pedal travel sensor (which I'm told may be the issue with my ABS).

Share this post


Link to post

There has been very little car work the past few months. I'm going to MSR-C this weekend, so I have done a few things. New rotors all around went on 2 weeks ago. The old ones don't really look bad, but they at least need to be resurfaced. Rotors are so cheap, I figure if they were coming off I might as well replace them. The old ones went on the car when I got it years ago, so I figure I've gotten my money's worth out of them. Made sure to toss a little anti seize on a few of the parts so they come off easily again next time this happens.

The brake pedal travel sensor was a pain. The old one came out easily enough, but getting the dang clip that holds it all in back in place was a struggle. I measured the old one with a multi meter when it came out, and I get basically the same readings from the new and old pieces. Oh well, I suppose I have a spare now if I need one.

Even after multiple emails to the company that made the under tray, I got no response. So my hopes of getting actual replacement parts were dashed. I was able to hammer one of the brackets into a shape resembling the correct dimensions, and it bolted up easily enough. I have some aluminum I'm going to hack up this week to try to bolt onto the other side. One way or another, I'll get that attached this week.

I threw in a new oil filter for good measure. I'd like to give it a wash this week, but not sure the weather is going to cooperate.

Share this post


Link to post

Finally spent the time to get the front bumper and under tray back in place. My fab skills are shameful, but it's done. I don't want to talk about how long I spent on this dumb little bracket... I would have preferred to make it a single piece and just bend it as necessary, but the lack of the decent workbench and vice, much less a metal brake, kind of required this multi piece approach. 

Are all the edges square to each other? No
Is is pretty to look at? Absolutely not
Does it hold thing in place? It sure as heck does!
Did it stay in place through two off track excursions, both forward and backwards? It sure did!

bracket.thumb.jpg.3b23b5be275456626a368586fc56aec6.jpg

I couldn't find my rivnut install tool, so I ordered a slightly nicer kit on amazon. So far so good on that front. Now that I have dimensions that work I'll probably make a better looking bracket where all the flat edges line up better. But this one does work, so no big rush.

I went out to MSR-C with TDE this past weekend. Didn't have a ton of confidence in the faster braking zones. Botched a downshift going into T1, leading to a 180 spin and the backwards off track adventure. Same Turn in a different session, hit the brakes and just didn't have the braking force I was expecting, leading to a forward off track adventure. Making to tap the brake and actually feel for positive feedback gave me good brakes the rest of the weekend, so some adjustments to my driving style could be the fix for now.

As I expected, the ABS is still non-op. I may need to suck it up and replace the ABS pump. It's not supposed to be that tough of a job, I just didn't want to do it. At least these street tires seem to be pretty resistant to flat spotting as long as I don't do anything too crazy.

The second off track did a little bit of damage. I noticed some terrible rattling and banging while heading back to the pits. Steering and brakes felt fine but I was fearing the worst. When I got the car stopped and walked around I noticed the exhaust hanging pretty low, I had an idea of the culprit. It broke two exhaust hangers on the muffler and tore a hole in the side.

exhaust1.thumb.jpg.a28c09a67533b4295f9fba3bbc87509a.jpg

Doghouse performance got it welded back up for me. I missed the last session, but no big deal there. I got a couple rides with instructors, which always makes me feel like a beginner again. The ride in a Audi TT-S with it's AWD was a very strange experience. I'm so used to RWD dynamics and handling, the pull from the front felt so strange. I'm very jealous of modern high performance brakes and ABS systems.

exhaust2.thumb.jpg.502c457e97f621c1566b7812a9beb5a1.jpg

Once the exhaust was reattached, things were all good. For a little bit... After the first Sunday session, I was checking tire pressures, letting the car run and cool down, when I started hearing a horrible rattle. I shut the car off real quick and started looking around. Right after this, someone stopped by and told me they saw something come off my car they had to dodge on track after giving me a pass. Parts falling off, things rattling, not a good feeling. I noticed the front grill was no longer there.

nogrill.thumb.jpg.51fbd783f3796c72546bad9fbdde97a3.jpg

Some people may notice another issue with this picture, but I didn't see it until later. I did find what was left of the grill wedged on top of the power steering pump. Something definitely hit it. It's not particularly tough plastic, so it wouldn't take much do to this.

grill.thumb.jpg.88604216adcd1368f2468896e8559460.jpg

I wasn't too worried about this, and the radiator looked good so I figured we were back in business. Sitting at the grid for the next session, the rattle started back up. I revved it a bit and it wasn't tied to RPMs. I really wanted to just ignore it, but I thought better of it. Popped the hood some of the plastic shrouding was shaking like mad. Kill the power and it stopped. Dean noticed the broken fan blade before I did. I have a better electric puller fan on the back of the radiator so I wouldn't miss this one at all. Pulled the power to the fan, which was conveniently located on the bottom of the fan housing. Access to this was easy since the grill was in the trash can at this point. Taped the wire and connector to the bumper with some painters tape, and didn't even miss a full lap of driving time. I did get some questions later from onlookers who were curious what the problem was at the grid were some painters tape was the answer.

The car was good no problems on track on Sunday, besides the grill incident. Things felt good and I had much more confidence in the brakes. I was able to get one of the instructors to ride with me last session to call me out on any bad habits I might be forming. He definitely had some helpful pointers but gave me a generally passing grade which was nice to hear. I think I'm much more critical of my mistakes than other people are.

I scheduled some private coaching from Adam Poland at Doghouse for next Thursday, so I'm pretty excited about that. I'm hoping he can give me some more pointers on car setup, in addition to the actual driving feedback. As we all know, driving is fun. It's even more fun when your car isn't breaking all the time. I talked to a bunch of nice folks this weekend. If I met any of you out there, please feel free to chime in and discuss how bad the car looks in person.

Share this post


Link to post

After some illness and scheduling conflict, I finally made it out to Cresson this morning to do some coaching with Adam Poland. We were the only car on track since it rained few days ago, so the track was veeery green. First session I managed a 1:25.2, which I was fairly pleased with on street tires (a fresh set of RS4s). The car was pushing pretty bad in big bend, the long right hander, so we threw the car on the rack to check things out. There was a fair amount of slop in the passenger side end link, were it seems I stripped the bolt. That was tightened as best as possible, but I'll get a replacement ordered. Went out for 1 more session, and put down a 1:24.135 per the Aim Solo. That's within 2 tenths of my personal best on NT01s.

I'll be back out at the track this weekend the TDE. I'm hoping with some good weather and a bit of hot rubber to get the track in better shape (gotta get those excuses in there, lol), I might be able to bring that time down a bit more. RaceStudio says my theoretical best is 1:22.5, so there's still plenty of headroom left. Thanks to Adam and the guys at Doghouse, not a bad way to spend a Thursday morning.

My lap times are fairly consistent once I get going, which I'm pleased with.

Session 1

S1.PNG.645fa2a38df239c5b131091aa327868f.PNG

Session 2

S2.PNG.5d6ff30237a72287ba160505801dda44.PNG

Share this post


Link to post

No problems with the car this past weekend. New a new PB for MSRC 1.7 CW of 1:23.96 which exactly matches my PB going CCW. Data shows a theoretical best of 1:21 and change now, so there's plenty of time left on the table. My best lap didn't actually have any of my individual best sectors, which I found a little bit surprising.

I'm liking the RS4s. The tread still looks good after 10 sessions, and they don't fall off like the RE71s did.

I have a few plans over the winter break. Going to try to address the exhaust rattles, redo the sunroof panel, clean up some hanging wires around the dash, and possibly do some new rear spring perches. Other then that, the car seems to be in a pretty good spot. It will be 25 years old in 2020, so I'll try to get it inspected again since the sniff test won't be necessary. I'd like to make it to a new track in 2020 as well, probably ECR for a start.

Share this post


Link to post
43 minutes ago, SpaceRangerJoe said:

I'm liking the RS4s. The tread still looks good after 10 sessions, and they don't fall off like the RE71s did.

The only shitty thing about RS4s is their availability 10 months out of the year 😂

Share this post


Link to post
25 minutes ago, Hollywood said:

The only shitty thing about RS4s is their availability 10 months out of the year 😂

No joke. I should have bought 2 sets before so I had some extra laying around.

Share this post


Link to post

No big updates recently. Put new brake pads on (Carbotech XP12 vs the old XP10). That solved the pad knock back issue, so that much medal travel must be a feature not a bug with those calipers. Rear pads still have about 50% of the meat on there, so they stay for a while. I'm still happy with the RS4s. They are wearing pretty well and I like the performance/consistency trade off. Honestly the car has been really solid the several track days. I hate to jinx that by saying it out loud, but here we are.

TDE last weekend was good. I reset my PB a few times, ended up around half a sec faster overall. There were 2 other guys out there running nearly identical times, so having some people to chase back and forth was a lot of fun. Got a little bit of rain practice on Sunday. I'm still not "good" by any stretch of the imagination, but I feel much more confident then last time.

The car is going to site in the garage for a little bit, ski trip and other travel plans are taking the fun budget for a little bit. Going to do some regular maintenance stuff, new plugs, clean filters, fix some rattles. I think I'm going to start down the aero road next. Going to start with a front splitter and blocking off the front a bit more. We'll see if that can get me a little bit more pace.

Share this post


Link to post

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...