The BMW UUC Digest Volume 2 : Issue 76 : "text" Format Messages in this Issue: E36 electrical failure Re: GC rear shock mounts Re: GC rear shock mounts Re: GC rear shock mounts Re: Is this a record? Re: Is this a record? Re: Cross drilled? (was: Time for F rotors and pads - Re: Cross drilled? (was: Time for F rotors and pads - Re: Drilled Rotors Re: Time for F rotors and pads Re: Time for F rotors and pads Re: Supercharger Re: Supercharger ABS Problem Re: Time for F rotors and pads
---------------------------------------------------------------------- Date: Wed, 10 Mar 2004 15:39:32 -0500 From: "Robinson, Lee" <[EMAIL PROTECTED]> To: "'UUCDigest'" <[EMAIL PROTECTED]> Subject: E36 electrical failure Message-ID: <[EMAIL PROTECTED]> Everyone, I have a friend with a 98 323is who's experiencing some electrical problems with her car. A couple fo days ago while driving, the gauge cluster apparently quit working while she was driving the car. She pulled over & shut off the car, which then wouldn't re-start. She then had the car towed to a shop, Bowman Motor Works, in ATL. This is a place I know well & respect. After 2 days of trying to figure out what the problem is they haven't come up with much except that there seems to be no power flow through the loom to the starter & some relays. They didn't charge her anything for the work, but recommended she take it to a local dealer. Since I know these guys aren't idiots & would check something like the battery, I'm kind of confused as to why they couldn't track this down. Anybody seen anything like this on an E36 before? I really don't have time to mess with it as I'm busy at work & have my M3 in parts with a track event this weekend, otherwise I mess with it for a little while. Thanks, Lee ------------------------------ Date: Wed, 10 Mar 2004 15:15:05 -0500 From: ben keyes <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: Re: GC rear shock mounts Message-ID: <[EMAIL PROTECTED]> Brian Daley wrote: > In my recent quest for RSM's I came across them at M3 Motorwerks. > http://www.m3motorwerks.com/index.php > There's a link to them right on the main page. Seems like a very reasonable price > too. > No affiliation, etc. They were just very helpful in answering my questions so I > figure they deserve a plug. they are just re-selling Ground Control and JT-Designs mounts. the JT-Designs ones look like they're a somewhat different design than they used to be, but I'd still go with GC based on how crappy the prior JT ones were. Ben ------------------------------ Date: Wed, 10 Mar 2004 14:12:50 -0800 (PST) From: Brian Daley <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: Re: GC rear shock mounts Message-ID: <[EMAIL PROTECTED]> -----Original Message----- >From: "J. Ochi" <[EMAIL PROTECTED]> >>I do wonder about noise though... Will these mounts result in banging, >>squeeking, creaking, etc.? > >Installed correctly, you won't get any banging/squeaking/creaking. I've >heard reports that if you don't tighten up the top shock nut correctly, you >may get squeaking and creaking, but haven't experienced that myself. Most >of those reports, though, are a little suspect - they tend to come from >proponents of the JT Design rear shock mount... By that do you mean that reports of squeaking RSMs have been from people with the JT-Design pieces, or that reports of GC RSMs squeaking are an attempt by JT-Design proponents to discredit the GC parts? Brian '94 325ic ------------------------------ Date: Wed, 10 Mar 2004 14:40:41 -0800 (PST) From: Brian Daley <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: Re: GC rear shock mounts Message-ID: <[EMAIL PROTECTED]> -----Original Message----- From: ben keyes <[EMAIL PROTECTED]> Brian Daley wrote: >> In my recent quest for RSM's I came across them at M3 Motorwerks. >> http://www.m3motorwerks.com/index.php >> There's a link to them right on the main page. Seems like a very reasonable price >> too. >> No affiliation, etc. They were just very helpful in answering my questions so I >> figure they deserve a plug. > >they are just re-selling Ground Control and JT-Designs mounts. > >the JT-Designs ones look like they're a somewhat different design >than they used to be, but I'd still go with GC based on how >crappy the prior JT ones were. Ben, I was aware of that, just pointing out a source for the GC urethane street RSMs that had been mentioned at what I thought was a decent price. I couldn't even find the part on GC's website. What do you find crappy about the JTD RSM's? Just curious as they seem very similar to the GCs. Brian '94 325ic ------------------------------ Date: Wed, 10 Mar 2004 12:46:02 -0800 (PST) From: david kroth <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: Re: Is this a record? Message-ID: <[EMAIL PROTECTED]> Keving wrote: > I think my battery is finally starting to go, but > get this, I looked up my > records and this Interstate battery is 7 years and 4 > months old. That seems > like it's on the far right of the curve. > > -Kevin Excellent battery life, but not the record. I put a new BMW battery in my E36 in early spring 1996 (March? April? - The records are at home). I just replaced it this past November. That's 7 years and 7 or 8 months. The battery was fine, but I was getting nervous... ===== David Kroth [EMAIL PROTECTED] __________________________________ Do you Yahoo!? Yahoo! Search - Find what you�re looking for faster http://search.yahoo.com ------------------------------ Date: Wed, 10 Mar 2004 16:14:51 -0500 From: "Chris Baker" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Subject: Re: Is this a record? Message-ID: <[EMAIL PROTECTED]> I just replaced my battery about 2 months ago. The car only had 55,000 miles on it when I got it almost 4 years ago (146,000 now) and I think it was original, although I'm not positive. If it was, that would make it about 9.5 years old when I replaced it. Chris B. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of david kroth Sent: Wednesday, March 10, 2004 3:46 PM To: [EMAIL PROTECTED] Subject: Re: [UUC] Is this a record? Search the ARCHIVES:http://www.mail-archive.com/[EMAIL PROTECTED] Keving wrote: > I think my battery is finally starting to go, but > get this, I looked up my > records and this Interstate battery is 7 years and 4 > months old. That seems > like it's on the far right of the curve. > > -Kevin Excellent battery life, but not the record. I put a new BMW battery in my E36 in early spring 1996 (March? April? - The records are at home). I just replaced it this past November. That's 7 years and 7 or 8 months. The battery was fine, but I was getting nervous... ===== David Kroth [EMAIL PROTECTED] __________________________________ Do you Yahoo!? Yahoo! Search - Find what youre looking for faster http://search.yahoo.com ________________________________________________________________________ __ In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA. UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate Short Shifter - accept no substitutes! 908-874-9092 . http://www.uucmotorwerks.com ------------------------------ Date: Wed, 10 Mar 2004 12:47:39 -0800 (PST) From: Gary Derian <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: Re: Cross drilled? (was: Time for F rotors and pads - Message-ID: <[EMAIL PROTECTED]> This set off my BS meter. A 12 inch rotor in a 24 inch wheel/tire adds very little rotational inertial, about 6% of its mass. A 20 lb rotor feels like 21 lb in the car(not rotating). Gary Derian > corners on my 325ic last weekend. Maybe it's my > imagination, but I swear I can feel a difference > (decrease) in acceleration. The car just *feels* > heavier. I didn't think to weigh the new rotors > before I put them on. I wonder what the increase in > mass is compared to the old rotors. ------------------------------ Date: Wed, 10 Mar 2004 14:29:42 -0800 (PST) From: Brian Daley <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: Re: Cross drilled? (was: Time for F rotors and pads - Message-ID: <[EMAIL PROTECTED]> Guess it's my imagination then. That might be a record for a response from you Gary, three complete sentences! Brian -----Original Message----- From: Gary Derian <[EMAIL PROTECTED]> Sent: Mar 10, 2004 12:47 PM To: [EMAIL PROTECTED] Subject: Re: [UUC] Cross drilled? (was: Time for F rotors and pads - Search the ARCHIVES:http://www.mail-archive.com/[EMAIL PROTECTED] This set off my BS meter. A 12 inch rotor in a 24 inch wheel/tire adds very little rotational inertial, about 6% of its mass. A 20 lb rotor feels like 21 lb in the car(not rotating). Gary Derian > corners on my 325ic last weekend. Maybe it's my > imagination, but I swear I can feel a difference > (decrease) in acceleration. The car just *feels* > heavier. I didn't think to weigh the new rotors > before I put them on. I wonder what the increase in > mass is compared to the old rotors. __________________________________________________________________________ In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA. UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate Short Shifter - accept no substitutes! 908-874-9092 . http://www.uucmotorwerks.com ------------------------------ Date: 10 Mar 2004 21:22:28 -0000 From: <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: Re: Drilled Rotors Message-ID: <[EMAIL PROTECTED]> > I guess that's what it comes down to - the limiting factor is heat capacity, as the > rotor will always have to absorb heat faster than it can > dissipate it so the more heat it can absorb the harder it is to induce fade. Drilled rotors see considerably higher heat than standard rotors -- I can say this both anecdotally, having faded pads on drilled rotors that held up well with standard rotors, as well as factually, as I've been party to tests where a team used temp paint to test the hypothesis. There's no benefit to drilled rotors outside of reduced mass, and even that is suspect. Then again, they look real pretty behind open wheel designs. ;-) -peter*g ------------------------------ Date: Wed, 10 Mar 2004 13:39:38 -0800 From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Subject: Re: Time for F rotors and pads Message-ID: <[EMAIL PROTECTED]> " convection, conduction, radiation" Yea, what Gary ("I've got the answers today")Derian said. _Kevin ------------------------------ Date: Wed, 10 Mar 2004 14:54:10 -0800 (PST) From: Brian Daley <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: Re: Time for F rotors and pads Message-ID: <[EMAIL PROTECTED]> Joe, Good discussion! I like your leaky bucket analogy. Regarding your comment below, the wheel *does* act as a heatsink. I know I wouldn't want to touch the wheels on my Mustang immediately after even normal braking in street driving. They are polished forged aluminum, so the material and lack of insulating paint may be a factor. Brian '94 325ic By the way, did you ever get your struts swapped out? I'm in Marlborough and I have a spring compressor and air tools if you want to give it a shot. -----Original Message----- From: [EMAIL PROTECTED] Although, with liberal use of polished mating surfaces and thermal paste, it may be possible to use the wheel rim as a nice big heatsink. -- Joe ------------------------------ Date: Wed, 10 Mar 2004 13:44:14 -0800 From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Subject: Re: Supercharger Message-ID: <[EMAIL PROTECTED]> Gary, Excellent, obviously well engineered from the quiescent to the engagement mode. Thanks. -Kevin ------------------------------ Date: Wed, 10 Mar 2004 14:24:18 -0800 (PST) From: Brian Daley <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: Re: Supercharger Message-ID: <[EMAIL PROTECTED]> -----Original Message----- From: [EMAIL PROTECTED] <snipped> >As a first pass, I wouldn't think that a simple switch to turn on the >supercharger would be a good thing as the fuel system would also have to be >coupled into the system to prevent an initial leaning of the intake charge >until the normal feedback loop could react. Kevin, I'd think a mass airflow system would handle that pretty gracefully. The ECM knows how much air is coming in on a given intake stroke and fuels appropriately before seeing any feedback. The lag is probably less than one crank rotation. ECMs typically also have a fuel modifier based on throttle position or rate-of-change that would signal an abrupt increase in airflow. Obviously that wouldn't apply in this case as the spike in airflow would not be accompanied by a change in throttle position. Brian ------------------------------ Date: Wed, 10 Mar 2004 15:42:28 -0600 From: "Kris Welhart" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Subject: ABS Problem Message-ID: <[EMAIL PROTECTED]> My Apologies if this is a repost, but I did not see the first one on the digest. Hello Brett and Group, I have pulled the codes from my 4/94 build M3 that is triggering a ABS light. The codes I received are as follows: 113 front left wheel speed 114 front right wheel speed 132 no description I have cleaned the sensors with brake cleaner twice with no improvement. The fault has been triggered around a dozen times after the codes were cleared and read again. Any insight is appreciated. Kris 95 M3 98 M3 ------------------------------ Date: Wed, 10 Mar 2004 17:37:21 -0500 (EST) From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] (bmw list) Subject: Re: Time for F rotors and pads Message-ID: <[EMAIL PROTECTED]> >From [EMAIL PROTECTED] > >Search the ARCHIVES:http://www.mail-archive.com/[EMAIL PROTECTED] > > >Brian notes: > >" Heat >capacity isn't really the critical factor - you don't want the rotors to >absorb heat, you want them to radiate heat." > >Radiating is one mode of heat dissipation the other is heat transfer by >having another fluid/medium (air) pass over or through the rotors. Then to >a lesser degree there is heat transfer through the brake fluid and >components of the braking system. > >-Kevin > Hmmm, I'm bored, so I will wander about in this topic a bit. If you have a car moving at some speed and you brake to a lower speed your braking system has to disipate the difference in kinetic energy. That would be Joules. Factor in how fast you do it and you have Watts. Now, the brake system is like a leaky bucket. I can only dissipate to the air so much energy per second. If I put energy in faster than I can take it away things heat up. Of course, the bucket becomes more leaky as a function of temperature, but we will neglect that for now (as I assume that your rotors aren't going incandescent while in use... if not this gets more interesting) Since the energy input to the brake system is effectively at the contact point of the pad and the rotor and the pad is a relatively poor conductor of heat, most of the energy is going to go into the rotor. In use, the brake system will be accepting energy much faster than it can reject it, there will be a temperature rise in the system. Heat will be rejected from the system by either conduction, convection, or radiation. Conduction will be the least usefull mechanisim here. The only things that we can conduct heat to are the caliper and the wheel hub [1], neither of which is a really good place to dump heat. Convection is probably the predominant heat transfer mode and this depends on the airflow over the rotor. This is where a vented rotor comes in. In a perfect world, the rotor acts as a centrifugal pump and moves air from the hub to the rim due to the rotation of the rotor. The air flow through the vents cools the rotor and all it well. In the real world, these vents can get clogged with brake dust and the layer of rust that forms is a good insulator. I wonder if anyone has studied the thermal efficiency of a new rotor vs. a used rotor... Radiation is an odd one. I am not sure just how hot rotors get in use. If they stay below 300 or so, then convection is probably more important than radiation. If they get up into the 700 degree range, then radiation and convection will probably be about equal and above that (the glowing rotor crowd) radiation will probably start to take over as the dominant heat transfer mechanisim (I need to go check my books again). We know that we are going to have a significant temperature rise during braking and we are interested in getting the temperature of the rotor down to a temperature that won't damage the pads and keeping the caliper temperature below the boiling point of the brake fluid. To me this means that we want a rotor material with good thermal conductivity and a high heat capacity. This means that the energy we dump into the rotor will distribute itself throughout the rotor (uniform temperature distribution) and will have as small a temperature rise as possible. It is possible that the only advantage a well used set of vented rotors has over solid rotors is the added mass (thermal capacity) and strength (increases with the cube of the thickness) to prevent warping. I suspect that the rotor is the least of the worries in the braking system. The energy dumped into the pad, which due to the lower thermal conductivity and capacity will be less than the rotor but not insignificant, must be disipated by the caliper and caliper mounts. Unfortunately, this is also where the brake fluid is and that is not where we want the heat to go. So how about fins on the calipers? Does anyone make calipers like that? This is also a situation where painting the calipers is probably bad as it acts as an insulator. Hmmmm... intersting... [1] Although, with liberal use of polished mating surfaces and thermal paste, it may be possible to use the wheel rim as a nice big heatsink. -- Joe -- Joseph M. Krzeszewski Network Operations [EMAIL PROTECTED] Jack of All Trades, Master of None... Yet ------------------------------ End of [bmwuucdigest] digest(15 messages) **********
