[uucdigest] Monday, February 10 2003 Volume 03 : Number 6101
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Send 'em to [EMAIL PROTECTED] |__________________________________________________________________ In this BMW UUC Digest: Re: [uuc] Diagnosis Complete - Bad Rear Wheel Bearing Re: [uuc] Diagnosis Complete - Bad Rear Wheel Bearing RE: [uuc] Diagnosis Complete - Bad Rear Wheel Bearing [uuc] Wheely bad noises Re: [uuc] E36 sways, WTB M3 rear Re: [uuc] E36 sways, WTB M3 rear [uuc] Diagnosis Complete - Bad Rear Wheel Bearing Re: [uuc] E36 sways [uuc] Re: Urethane bushings on e36 daily driver/track car for rear suspension [uuc] <E28> 1988 M5 For Sale ---------------------------------------------------------------------- Date: Sun, 09 Feb 2003 18:36:50 -0800 From: "Bora Akyol (BMW)" <[EMAIL PROTECTED]> Subject: Re: [uuc] Diagnosis Complete - Bad Rear Wheel Bearing On 2/9/03 6:17 PM, "Scott & Charlotte Miller" <[EMAIL PROTECTED]> wrote: > Bill Gosma and I spent some time trying to track down the noise coming from > the rear of my 1990 325i. After much poking, proding, listening with a > stethescope (thanks Darrel), jacking things up and down, etc etc, we > narrowed it down to the LR wheel bearing. In fact, if I had thought to > simply grab the wheel and tire and push and pull it a bit, I would have > known that without all the other work. Oh well, guess I've got another > project. > > Scott Miller > GGC BMW CCA > > Scott Make sure you borrow the rear wheel bearing tool to do the job, I hear it makes it much easier. ------------------------------ Date: Sun, 9 Feb 2003 18:59:18 -0800 From: "Scott & Charlotte Miller" <[EMAIL PROTECTED]> Subject: Re: [uuc] Diagnosis Complete - Bad Rear Wheel Bearing Thanks Pat, the CV joints *seem to be* good. But what do I know? Scott >Date: Sun, 9 Feb 2003 21:28:24 -0500 >From: "Pat Donahue" <[EMAIL PROTECTED]> >Subject: Re: [uuc] Diagnosis Complete - Bad Rear Wheel Bearing > >Yeah, when I was building my '88 325 into a race car I reasoned that I >wanted the wheel bearings to be in really good shape. I replaced all of 'em >whether I thought they needed it or not. Never had a lick of trouble with >'em then. Did the same with the CV joints in the rear also. (not that I'd >make subtle hints or anything) > >Geeeze ------------------------------ Date: Sun, 9 Feb 2003 19:39:56 -0800 From: "John Coffin" <[EMAIL PROTECTED]> Subject: RE: [uuc] Diagnosis Complete - Bad Rear Wheel Bearing Hi Scott, I think I have the correct factory hub puller for your car if you want to borrow it. - -John - -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Scott & Charlotte Miller Sent: Sunday, February 09, 2003 6:17 PM To: UUC Digest; E30 List Subject: [uuc] Diagnosis Complete - Bad Rear Wheel Bearing Bill Gosma and I spent some time trying to track down the noise coming from the rear of my 1990 325i. After much poking, proding, listening with a stethescope (thanks Darrel), jacking things up and down, etc etc, we narrowed it down to the LR wheel bearing. In fact, if I had thought to simply grab the wheel and tire and push and pull it a bit, I would have known that without all the other work. Oh well, guess I've got another project. Scott Miller GGC BMW CCA ------------------------------ Date: Sun, 9 Feb 2003 19:52:44 -0800 From: "T WALROD" <[EMAIL PROTECTED]> Subject: [uuc] Wheely bad noises Scott said: Bill Gosma and I spent some time trying to track down the noise coming from the rear of my 1990 325i. After much poking, proding, listening with a stethescope (thanks Darrel), jacking things up and down, etc etc, we narrowed it down to the LR wheel bearing >>Musta been that sort of a day - I came off the bridge into Salem today and heard a horrible metallic scraping noise coming from the back of the car. It was there clutch in or out, right down to almost stopped, and present in left or right hand turns. I had about decided that some portion of the car was sitting on the driveshaft. Nothing jumped out at me as a problem when I looked under the car and pushed the wheels around so I drove home. Put the car up on jackstands and found the horrible scraping noise coming from the right rear. Pads and rotor looked good. On pulling the rotor a wee little triangular bit of gravel dropped on the floor. It had been rubbing right where the e-brake drum turns the corner to become a rotor disc. Reshaped the backing plate a bit and buttoned it back up. I love cheap and easy fixes! Tom ------------------------------ Date: Sun, 9 Feb 2003 23:51:25 -0500 From: "Gary Derian" <[EMAIL PROTECTED]> Subject: Re: [uuc] E36 sways, WTB M3 rear A stiffer rear bar increases weight transfer at the rear tires in a corner which reduces weight transfer at the front. The result is more weight on the inside front tire. The weight doesn't transfer to the inside front, less weight transfers away from it. Gary Derian > Just to better my own understanding, is this correct? What I've been > told, by what I thought were reputable sources, was that increasing the > stiffness of the rear bar actually transferred more weight to the front > inside tire, increasing grip there and reducing understeer. I know I've > seen Gary comment on this before and thought his comments were along the > same lines - is that right Gary? > > Regardless of the theory, It sounds like there is something to be gained > from an M3 bar. I definitely can't get away with $350-$400 for a new > aftermarket bar set, so is there any reason I shouldn't just try an M3 > rear bar? > > Anybody got a used 96+ M3 rear bar they want to sell? > > Thanks, > > Chris B. > > > Date: Thu, 6 Feb 2003 18:43:57 -0500 > > From: "Matt Tremmel" <[EMAIL PROTECTED]> > > Subject: Re: [uuc] E36 sways > > > > Chris > > > > 95 M3 sway (22.5) in the front and 95 M3 sway in the > > rear (19) will probably get you all the oversteer you want > > the cheapest. > > > > Based on stock springs, you get this (F/R distribution of > > total stiffness) > > > > M3 (22.5/19) Stock (24/18) > > Front stiffness 44% 55% > > Rear Stiffness 56% 45% > > > > More rear stiffness means more weight transfer to the > > rear, thus exceeding the grip of the rear tires sooner > > for a given lateral load. > > > > ------------------------------ Date: Sun, 9 Feb 2003 23:46:52 -0500 From: "Gary Derian" <[EMAIL PROTECTED]> Subject: Re: [uuc] E36 sways, WTB M3 rear Yes but things aren't that easy in the real world. The arms are stiffer on a thicker bar but not d^4, but d^3. Any compliance in bushings is greater for the stiffer bar. When it is done, the actual roll stiffness for the thicker bar is somewhat less than d^4. Gary Derian > > I dunno the numbers we're talking about, but going from a 19mm to a 20mm bar will > increase its stiffness 23%. Torsional stiffness is proportional to diameter^4. > ------------------------------ Date: Mon, 10 Feb 2003 10:05:52 -0500 From: "Gaudio, Stefano" <[EMAIL PROTECTED]> Subject: [uuc] Diagnosis Complete - Bad Rear Wheel Bearing Make sure to check your rear control arm bushing. I had a noise in my '98 M3 suspension and a mechanic diagnosed a bad wheel bearing by grabbing the tire and pushing and pulling. However, after closer inspection the bad bushing was allowing the free play. I ordered the part and got the wrong one since BMW official name for it is "ball bearing" for the outside bushing closer to the tire and just "bushing" for the inside bushing closer to the center of the car. Stefano in reply to - ------------------------------ Date: Sun, 9 Feb 2003 18:17:14 -0800 From: "Scott & Charlotte Miller" <[EMAIL PROTECTED]> Subject: [uuc] Diagnosis Complete - Bad Rear Wheel Bearing Bill Gosma and I spent some time trying to track down the noise coming from the rear of my 1990 325i. After much poking, proding, listening with a stethescope (thanks Darrel), jacking things up and down, etc etc, we narrowed it down to the LR wheel bearing. In fact, if I had thought to simply grab the wheel and tire and push and pull it a bit, I would have known that without all the other work. Oh well, guess I've got another project. Scott Miller GGC BMW CCA - ------------------------------ Stefano ------------------------------ Date: Mon, 10 Feb 2003 10:47:59 -0500 From: "Gary Derian" <[EMAIL PROTECTED]> Subject: Re: [uuc] E36 sways Matt, typical weight transfer distribution for a rear drive car is 80% at the front. I suspect you are leaving some factors out of your calculations. Gary Derian > Gary, > The stiffnesses are based on anti-roll bar diameter and arm lengths. > I don't have anything in for the linkages. > > Spring stiffnesses are based on number of coils, wire diameter, etc. > They match what information I found on the web (Ben Liaw?) with > measured spring stiffness' somewhere (~90 lbf/in front > and 300 lbf/in rear). The rear's should adjusted for their effective rate > since they are slightly inboard of the unsprung weight. > > The roll centers, COG, track width, etc. are used with the total F/R > stiffness to determine roll couples and thus weight transfer. > > The important thing to remember is the RATIO of front to rear > stiffness is what matters. The weight transfers regardless, it > just gets split to the rear and the front by the ratio of the > front to rear stiffness. > > For example, on my car, 3240 pounds with me int it, > a 0.8g turn (steady state, like a skid pad) results in > about 850 lb of weight transfer, 336 on the front, > 514 on the rear (with my bars, 22.5/18). Put in the stock > 325 bars (24/15), it goes to 450 front , 400 rear. > More load on the front, thus understeer sooner, but the > total weight transfer stays the same. > > You could also play around with the weight transfer by > adjusting CG, track width, and roll center heights, and wheelbase > (affects the weight transfer due roll center height changes), but that > is pretty hard to do unless you are building the car from scratch! > > Matt > 1994 325is > > >Matt, are your stiffness calcs only based on anti-roll bar diameter or do > >you have all the factors included, linkage, roll center heights, etc. > > >Gary Derian > >> > >> Based on stock springs, you get this (F/R distribution of > >> total stiffness) > >> > >> M3 (22.5/19) Stock (24/18) > >> Front stiffness 44% 55% > >> Rear Stiffness 56% 45% > > ------------------------------ Date: Mon, 10 Feb 2003 11:53:35 -0500 From: "James Clay" <[EMAIL PROTECTED]> Subject: [uuc] Re: Urethane bushings on e36 daily driver/track car for rear suspension First, all of the bushings you mention are legal in stock class (including BMW, SCCA for autocross, etc - may not be legal in SCCA SS and T classes for road racing). They are all very streetable and don't add much of the PITA factor because they don't directly take a load - they are more of a pivot point. The exceptions are the subframe bushings which will add a little gear noise, slightly more when coupled with the solid diff bushings, because they give the vibrations from the diff a better channel to invade the car shell. The rear bushings are definitely better than replacement stock rubber. The main difference I feel is the rear rotates or takes a set quicker and is consistent through the corner instead of twisting more. This joint, if the choice was made by a mechanical engineer instead of an ergonomics guy would have been a spherical bearing. It is made to move on 3 axes, which only a ball joint can do without eventual wear. I think the urethane will be better than rubber, even long term, and it is my choice on my street car. However, solid is the way it should be done, but it will make the car louder (they click). If I had one car that I took to the track a bit, I lived where the roads are decent, and I wasn't extra sensitive to added noise, I would probably do solid. James James Clay http://www.bimmerworld.com Engineered BMW Performance 540.639.9648 - ----- Original Message ----- From: <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Sunday, February 09, 2003 9:08 AM Subject: Urethane bushings on e36 daily driver/track car for rear suspension > In an effort to make my '92 e36 325IS more predictable and easier to rotate > at the limit on the track I am strongly considering replacing the stock rear > suspension bushings with urethane components such as the POWERFLEX bushings > sold by Bimmerworld. They are 25% stiffer then stock rubber. The bushings in > question are the rear trailing arm, control arm, subframe bushings and > possibly differential mounts. A few questions, > > 1. How is the streetability and durability effected with urethane, the car is > on H & R sport and Konis with stock bars and is driven spring thru fall in > New England? > > 2. Are Urethane bushings a significant performance advantage over new stock > rubber bushings or do you really have to get into the solid bushings for > noticeable improvements. Can you feel the rear rotation earlier and is it > more predictable and recoverable at the limit? > > 3. Are the urethane bushings legal for BMWCCA stock classes and are they > widely used? > > Thanks, > > Gordon Geick > 1992 e36 325IS > 1976 Alfa Spider (lot of fun for the daily commute) > > ------------------------------ Date: Mon, 10 Feb 2003 14:22:52 -0500 From: "Andrew E. Skopp" <[EMAIL PROTECTED]> Subject: [uuc] <E28> 1988 M5 For Sale My brother-in-law has reluctantly decided to sell his M5. I offered to send his listing to the digest. He writes: 1988 M5, VIN WBSDC9302J2791414, Black/Tan, 102K miles, excellent condition inside & out, Dunlop SP Sports, new shocks (SLS eliminated), new water pump, Sony ES Deck with matching orange illumination & 6-disc changer, Dinan chip, looks & runs great. $12,500. (301) 947-7880. [EMAIL PROTECTED] (David) Car is in the Rockville, MD area. Please contact David directly. Thanks for your consideration. Andrew E. Skopp Gallagher Evelius & Jones LLP 218 North Charles Street, 4th Floor Baltimore, Maryland 21201 Telephone: (410) 347-1365 Facsimile: (410) 468-2786 E-mail: [EMAIL PROTECTED] CONFIDENTIALITY NOTICE: The information contained in this email message is ATTORNEY PRIVILEGED AND CONFIDENTIAL INFORMATION intended ONLY for the use of the individual or entity named herein. If you are not the intended recipient or the employee or agent responsible for delivering it to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this communication in error, please immediately notify us by telephone at (410)727-7702 and return the original message by reply email. Thank you for your cooperation. ------------------------------ End of [uucdigest] V3 #6101 *************************** | | In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA. |________________________________________ | Please visit these UUC-approved BMW parts vendors/service providers: | (listed alphabetically) | | Autoscope-Motorsports - http://www.autoscope-motorsports.com | |==================================================== | | Koala MotorSport . 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