[uucdigest] Tuesday, January 21 2003 Volume 03 : Number 6040
_________________________________________________________________ | | Search the ARCHIVES: | http://www.mail-archive.com/[email protected] | | Visit Richard Nott's Ultimate BMW Database: | http://www.bmwdatabase.com | | For all available Digest commands including unsubscribe/subscribe, | visit the BMW UUC Digest page: http://www.uucdigest.com | | Send SUBMISSIONS to [EMAIL PROTECTED] | Complaints? Send 'em to [EMAIL PROTECTED] if you must. | Technical Problems? Send 'em to [EMAIL PROTECTED] |__________________________________________________________________ In this BMW UUC Digest: [uuc] Re: E30 convertible weight ballast [uuc] Re: E30 convertible weight ballast Re: [uuc] Re: E30 convertible weight ballast [uuc] For those who thought BMW didn't rally anymore Re: [uuc] Re: E30 convertible weight ballast Re: [uuc] Re: E30 convertible weight ballast [uuc] eta engine & tranny FS (must go!) Re: [uuc] Re: E30 convertible weight ballast [uuc] [FS] Nady PMC-2 Intercom [uuc] Weight Savings [uuc] <E36> Euro Headlights WITH Xenon Upgrade? [uuc] Cats and cars [uuc] Re: E30 convertible weight ballast ---------------------------------------------------------------------- Date: Mon, 20 Jan 2003 22:18:16 -0800 (PST) From: John Bolhuis <[EMAIL PROTECTED]> Subject: [uuc] Re: E30 convertible weight ballast On Mon, 20 Jan 2003, Neil Deshpande wrote: > Gary: > > I second this (in part). The mechanism of a > spring-mass damper is to be much smaller than the mass > to be damped, but 'move a lot more' to dissipate the > energy of the larger mass and cut down vibration. > > However, for a mass-only damper the action is > different. It changes the vibration characteristic of > the body itself and cuts down vibration that way. For > example, the tail of the iC may be resonant at the > same frequency as the cowl. Putting a mass on one > will take them out of sync. At least, that is how > I've always understood it. If it were a rigid mass > clamped to the body w/o a spring how would it 'move > more' to dissipate energy anyway? The mass in my iC is mounted via 4 fairly squishy rubber bushings. Is it a spring-mass damper or a mass-only damper? A little from column A, a little from column B? How springy does a mount have to be to be considered a spring? Rubber is springy. So is a steel bolt, albeit much less so. Don't you wanna see the thing? Sure you do. Look in my gallery: <http://www.bolhuijo.com/gallery/automobile> - -- "It is an honor to be Cookie Monster." -Sesame Street spokeswoman Audrey Shapiro ------------------------------ Date: Mon, 20 Jan 2003 22:39:29 -0800 (PST) From: John Bolhuis <[EMAIL PROTECTED]> Subject: [uuc] Re: E30 convertible weight ballast On Mon, 20 Jan 2003, Gary Derian wrote: > I like to modify cars as much as the next guy, but if I had an E30 > convertible, that would be my cruising around car and all my modification > energy would go into my M3 or M5 or some other car where performance > modifications had a purpose. Just my opinion of course. I'd never suggest > that dinking around with battery boxes and dampers is a futile exercise. Performance mods DO have a purpose. This is my race car! (auto-x of course) Though I do also tinker with my motorcycle carburetors. (carburetors?!? yes, carburetors.) > If the battery were used as the mass, it would fail in short > order due to constant vibration. The easiest solution for a > decidedly non performance car is to put the battery in the engine > compartment and a solid damper mass where it can do the most > effective damping. I'm still thinking a properly clamped-in gel cell battery would take a helluva lotta shaking without adverse effect. As for non-performance car, why I oughtta... Tell that to the M3 drivers I beat at the autocross this year! :-P (yeah, I'm a little cocky about it. Just don't ask me about Andy who keeps whoopin' on me with his 4-cylinder :) > Regardless, this thought experiment or gedanken experiment as Einstein would > say is certainly interesting and provoking. Indeed. You know, I still haven't driven the car since I took that darn weight out on Saturday. Maybe I'll like it! - -- "It is an honor to be Cookie Monster." -Sesame Street spokeswoman Audrey Shapiro ------------------------------ Date: Mon, 20 Jan 2003 22:59:01 -0800 From: Mark Dadgar <[EMAIL PROTECTED]> Subject: Re: [uuc] Re: E30 convertible weight ballast John Bolhuis at [EMAIL PROTECTED] wrote: > As for non-performance car, why I oughtta... Tell that to the M3 > drivers I beat at the autocross this year! :-P (yeah, I'm a little > cocky about it. Just don't ask me about Andy who keeps whoopin' on me > with his 4-cylinder :) If you've never seen John auto-x that poor E30 ragtop, you're missing out in a big, big way. We don't call him Sideways Bolhuis for nothin'. - - Mark - -- [EMAIL PROTECTED] ------------------------------ Date: Tue, 21 Jan 2003 08:41:04 -0500 From: "Robinson, Lee" <[EMAIL PROTECTED]> Subject: [uuc] For those who thought BMW didn't rally anymore A BMW X5 finished 9th in the car class at the Dakar this year. I believe it was even a diesel. The first diesel car to win a stage of the Dakar in over 25 years was one of the X5's. The top places went to the new Mistu Pajeros..... Lee ------------------------------ Date: Tue, 21 Jan 2003 08:40:39 -0500 From: "Gary Derian" <[EMAIL PROTECTED]> Subject: Re: [uuc] Re: E30 convertible weight ballast John, you can do anything you want! I was merely stating my personal opinion. That damper is a spring mass type. It is certainly tuned to one of the noticeably annoying vibration modes in the body. These change with the top up or down. I don't know which mode it handles. Put a video camera back there and see what it does. Dampers can have more than one mode, up-down mode and a front-rear mode, even a rocking mode. Gary Derian > On Mon, 20 Jan 2003, Gary Derian wrote: > > > I like to modify cars as much as the next guy, but if I had an E30 > > convertible, that would be my cruising around car and all my modification > > energy would go into my M3 or M5 or some other car where performance > > modifications had a purpose. Just my opinion of course. I'd never suggest > > that dinking around with battery boxes and dampers is a futile exercise. > > Performance mods DO have a purpose. This is my race car! (auto-x of > course) Though I do also tinker with my motorcycle carburetors. > (carburetors?!? yes, carburetors.) ------------------------------ Date: Tue, 21 Jan 2003 08:42:37 -0500 From: "Gary Derian" <[EMAIL PROTECTED]> Subject: Re: [uuc] Re: E30 convertible weight ballast The key is the natural frequency of the damper, the vibration mode you are trying to get rid of, and the mass of the damper compared to the mass of the body. Neil is the vibration guru so he'll have to take this further. Gary Derian > > The mass in my iC is mounted via 4 fairly squishy rubber bushings. > Is it a spring-mass damper or a mass-only damper? A little from > column A, a little from column B? How springy does a mount have to be > to be considered a spring? Rubber is springy. So is a steel bolt, > albeit much less so. > Don't you wanna see the thing? Sure you do. Look in my gallery: > <http://www.bolhuijo.com/gallery/automobile> > > -- > "It is an honor to be Cookie Monster." > -Sesame Street spokeswoman Audrey Shapiro > > ------------------------------ Date: Tue, 21 Jan 2003 10:09:37 -0500 From: "Luis Rueda" <[EMAIL PROTECTED]> Subject: [uuc] eta engine & tranny FS (must go!) The "i" engine/tranny have been installed on my '86 325. Unfortunately the eta engine/tranny have to go since I live in a townhouse w/out a garage & I don't have the space to keep them (my mechanic doesn't have the space to store them either & he wants them out of his shop ASAP). Both are in perfect working condition and I don't want to have to ship these so they're available for pickup only in Fairfax, VA. $250 for both (email me directly for details). Thank you, Luis '86 325e '86 325 soon to be "is" ------------------------------ Date: Tue, 21 Jan 2003 10:03:22 -0600 From: Sean Cordone <[EMAIL PROTECTED]> Subject: Re: [uuc] Re: E30 convertible weight ballast Don't forget there's a third factor, the mechanical loss, that also needs to be tweaked. Imagine for simplicity that the system is a mechanical beam, constrained not to move on one end. This system has a spectrum of natural resonant frequencies. A mass, rigidly connected to the free end of the beam, will just move the resonant frequency of the first vibrational mode lower. A second resonant system (mass/spring/damper) attached to the free end can actually dampen the vibration of the beam, by essentially sucking energy out of that resonance. To do this effectively, the second system has to be tuned to match the resonant frequency of the beam, and it has to be lossy. That means once you've got the mass/spring combination right, you've got to get the loss right (this also sets the resonance width in frequency). This is exactly analogous to picking a suspension spring/shock combo. It looks like BMW did this by suspending the mass with rubber bushings, which naturally act like a lossy spring. Another consideration: the mass has to be free to vibrate in the right orientation. Otherwise it just acts as a fixed added mass. The picture John posted sure makes it look like the mass is oriented, i.e. it's resonant frequency is different in different orientations. --SC John Bolhuis wrote: > The mass in my iC is mounted via 4 fairly squishy rubber bushings. >Is it a spring-mass damper or a mass-only damper? A little from >column A, a little from column B? How springy does a mount have to be >to be considered a spring? Rubber is springy. So is a steel bolt, >albeit much less so. > Don't you wanna see the thing? Sure you do. Look in my gallery: ><http://www.bolhuijo.com/gallery/automobile> > > ------------------------------ Date: Tue, 21 Jan 2003 10:10:53 -0600 From: "Ned Coonen" <[EMAIL PROTECTED]> Subject: [uuc] [FS] Nady PMC-2 Intercom New in box, never opened. My wife won this at our chapters annual dinner last weekend. I already have two so this one is for sale cheep. $55 including UPS to you (USA only). Here's more information on the unit. http://www.nadywireless.com/products/product_pgs/prcmoto_pg1.html Ned Coonen Windy City Chapter ------------------------------ Date: Tue, 21 Jan 2003 11:34:50 -0500 From: "Dorffer, Rich" <[EMAIL PROTECTED]> Subject: [uuc] Weight Savings John writes > > Also, in the interest of weight savings, is there a donut spare tire > for the e30? Honestly, with the traveling I do in that thing, a donut > spare would not be a handicap. (also, it's been over 10 years since I > had a flat, and I'm feeling lucky). John, I have a better idea. Skip the donut spare idea all together. Yeah, instead, I have a new soon-to-be-patented system that is much lighter than full size spares or even donut spares. Please read on... I combine a can of "Fix-uh-Flat", a little tire compressor (when you need more air than the "Fix-uh-Flat" provides), and a one-year membership to AAA for only $249. Ahhh, I can just see the money pouring in now. I bet in no time all the manufacturers will be clamoring for me to work out major purchasing deals for them. If anyone else that is interested, please give me a call at 555-FIX-FLAT. I can help all of you with your New Years resolution to remove weight. Regards, Rich - told my wife I was going to lose some weight this year....she didn't realize I was talking about the M3 :-) ------------------------------ Date: Tue, 21 Jan 2003 11:34:55 -0500 From: "Dorffer, Rich" <[EMAIL PROTECTED]> Subject: [uuc] <E36> Euro Headlights WITH Xenon Upgrade? Bill says > > I have Euro lights on my '97 328is and an upgrade kit to HIDs for my '02 > F150. This is made by Sylvania, and replaces the entire headlight > assembly. Boy, I would love you being driving behind me in either of my cars with you in your HID equipped F150. Those trucks already light up my life and the inside of my car. I bet you could read my car manual if it was sitting on my dash. > If it were me, I'd put in the Euros and be done with it. Agreed. Regards, Rich ------------------------------ Date: Tue, 21 Jan 2003 09:41:28 -0500 From: "BMWBITS" <[EMAIL PROTECTED]> Subject: [uuc] Cats and cars I got the following note from a friend today .....Was anyone here involved in the record attempt and thus able to verify the numbers ? According to World Records, 127 cats can be stuffed into a BMW 3 series sedan. 648 if you feed them thru a wood chipper first. Gene Bill & Shirley Proud, Tennessee..winters, Seattle..summers Long commute in between . ------------------------------ Date: Tue, 21 Jan 2003 08:39:30 -0800 From: [EMAIL PROTECTED] Subject: [uuc] Re: E30 convertible weight ballast Better idea - you know those flashlights that you shake up to light the bulb? Well, get a bunch of whatever is in those, mount it in the trunk over the spot where the weight was, and wire it into the electrical system. Then as the body shakes, it will generate the electricity need to run the car's systems. If you get a low voltage indication, just find a bumpier road. How much does that stuff weigh, anyway? BTW John, I know you were just kidding, but lest I start getting questions from others, my half-assed mods did not include removal of any body part - mine or the car's. Scott Miller GGC BMW CCA >Date: Mon, 20 Jan 2003 16:01:20 -0800 (PST) >From: Tammer Farid <[EMAIL PROTECTED]> >Subject: Re: [uuc] Re: E30 convertible weight ballast > >Perhaps. It depends on whether the rubber/metal block was >tuned to dampen a specific frequency or range of >frequencies, or if it is just a function of the mass. > >If the former, find that range and "cobble together" >something that includes your battery (remember to vent it!) >and a system to eliminate the same frequencies. You'd >probably have to use a very dense material to accomplish >the same task with a smaller piece. > >If the latter, it won't work because part of the mass >absorbing the vibrations will be the battery--which is what >you want to avoid. > >I'm not sure exactly how the stock E36 batt. copes with the >vibration; maybe you should look into that first. > >tammer ------------------------------ End of [uucdigest] V3 #6040 *************************** | | 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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