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Mail*LinkŪ SMTP Quattro Digest V3 #122 !!! Original message was too large. !!! !!! It is contained in the enclosure whose name !!! is the same as the subject of this message. !!! !!! A preview of the message follows: Quattro Digest Tuesday, 13 February 1996 Volume 03 : Number 122 In this issue: Al rotors Hella lights vs. PIAA (revisited) Low oil light Re: Oil Level light? Re: Oil Level light? Re: PROPELLER SHAFT 88 80Q RE: 1990 Coupe Heater Blower Extraction Re: Set Konis where? Re: Al rotors AUDI SPORT STICKERS ABT Performance Upgrades 83TQC handling Re: A/C problem/questions Re: LIGHTS - 5000CSTQ Anti-roll bars for 4000Q Body parts Re: Hella lights vs. PIAA (revisited) Re: ABT Performance Upgrades Re: A/C problem/questions "G'd out" 5k Al Rotors - The definitive answer (Looong) Re: Al Rotors - The definitive answer (Looong) See the end of the digest for information on subscribing to the quattro or quattro-digest mailing lists. - - - - - - - - - - - - - - - - - - - - - - - - - To submit a message to the quattro list, mail to quattro@coimbra.ans.net. - - - - - - - - - - - - - - - - - - - - - - - - - To unsubscribe, mail to majordomo@coimbra.ans.net and in the body of your note, say: unsubscribe quattro-digest - - - - - - - - - - - - - - - - - - - - - - - - - For access to the web archives, point your browser at: http://coimbra.ans.net/quattro.html - - - - - - - - - - - - - - - - - - - - - - - - - ---------------------------------------------------------------------- From: "Graydon D. Stuckey" <graydon@apollo.gmi.edu> Date: Mon, 12 Feb 1996 16:26:56 -0500 (EST) Subject: Al rotors On Mon, 12 Feb 1996, Robert S. Cohen wrote: > STEADIRIC wrote- > >>Sure, less is better, but c'mon man! > >>You tryin' to tell me that the relative rotational mass of the prowler > >>brakes Vs that of the viper brakes accounts for the better braking *more* > >>than does the relative mass of the vehicle and relative amounts of swept > >>area? > > > >Yes I am, do the math....... Don't know the math, LEARN IT if your going > >to pontificate. I know it....... Graydon knows it........ Scott knows > >it......... > > FALLACIOUS ARGUMENT ALERT. > > I'm gonna pontificate. Where's my mitre? > > AHEM, Eric, the rest of us don't _ know_ it! > > It is not manifestly obvious to me how this can be the case. Perhaps you > could share the math with the rest of us....? > > Before you accuse me of being lazy, I've briefly discussed the problem with > a physicist here. the upshot of our admittedly naive investigation was that > aluminum rotors would probably make for somewhat diminished stopping due to > the specific heat of the (light) aluminum rotor vs the (heavy) iron rotor. > Decelerating at the same rate, the aluminum rotor will get 40% hotter. > > Al Fe > Density g/cm^3 2.7 7.86 > Sp. Heat J/(g*degK) .9 .44 > > with these numbers, I calculate that for equal volumes (we simply swap > aluminum for iron) the iron rotor will be 2.9 times more massive. for equal > masses, the iron rotor will heat 1 degK for each .48 degK the aluminum > rotor heats. 2.9*.48= 1.392. So, a rotor of Al equal in volume to the > original Fe rotor will be increase in temperature 40% more than the iron > rotor for a given deceleration (energy input). There. I did the math. > > regarding the kinetic energy of the rotors themselves, which I think is the > factor Eric is alluding to, it is (m w^2 r^2) I think, where m is the mass > of the ring, w is the angular velocity, and r is the radius of the > idealized ring. Frankly, I (waving my hands) think this will pale in > comparison the energy of a 3000 lb car travelling at 100 kmph or so. > > End of Audience. Get out of my basilica..... ;-) Robert, Glen, Eric, at al, I never meant this to be a big heated argument. I was merely stating what I heard from Team Prowler. I didn't do the test myself, nor was I in attendance when the test was done, so take it with a grain of salt, not a Congressional seal of approval. My point was that the ALuminum rotors reduce the rotating inertia of the wheel/rotor assemblies, and that has a profound influence on the braking of the car. How much is not open t Received: by amgen.com with SMTP;13 Feb 1996 01:12:13 -0800 Received: from castle-smtp.amgen.com by amgen.com (5.0/SMI-SVR4) id AA17442; Tue, 13 Feb 1996 01:01:05 -0800 From: quattro-digest-owner@coimbra.ans.net Received: by castle-smtp.amgen.com; id BAA07698; Tue, 13 Feb 1996 01:01:04 -0800 Received: from coimbra.ans.net(147.225.1.100) by castle-smtp.amgen.com via smap (g3.0.3) id xma007696; Tue, 13 Feb 96 01:00:39 -0800 Received: (from daemon@localhost) by coimbra.ans.net (8.7.3/8.6.10) id DAA14584 for quattro-digest-outgoing; Tue, 13 Feb 1996 03:08:54 -0500 (EST) Received: (from daemon@localhost) by coimbra.ans.net (8.7.3/8.6.10) id DAA14577 for quattro-digest-send@coimbra.ans.net; Tue, 13 Feb 1996 03:08:52 -0500 (EST) Date: Tue, 13 Feb 1996 03:08:52 -0500 (EST) Message-Id: <199602130808.DAA14577@coimbra.ans.net> To: quattro-digest@coimbra.ans.net Subject: Quattro Digest V3 #122 Reply-To: quattro@coimbra.ans.net Sender: quattro-digest-owner@coimbra.ans.net Precedence: bulk content-length: 35993 Quattro Digest Tuesday, 13 February 1996 Volume 03 : Number 122 In this issue: Al rotors Hella lights vs. PIAA (revisited) Low oil light Re: Oil Level light? Re: Oil Level light? Re: PROPELLER SHAFT 88 80Q RE: 1990 Coupe Heater Blower Extraction Re: Set Konis where? Re: Al rotors AUDI SPORT STICKERS ABT Performance Upgrades 83TQC handling Re: A/C problem/questions Re: LIGHTS - 5000CSTQ Anti-roll bars for 4000Q Body parts Re: Hella lights vs. PIAA (revisited) Re: ABT Performance Upgrades Re: A/C problem/questions "G'd out" 5k Al Rotors - The definitive answer (Looong) Re: Al Rotors - The definitive answer (Looong) See the end of the digest for information on subscribing to the quattro or quattro-digest mailing lists. - - - - - - - - - - - - - - - - - - - - - - - - - To submit a message to the quattro list, mail to quattro@coimbra.ans.net. - - - - - - - - - - - - - - - - - - - - - - - - - To unsubscribe, mail to majordomo@coimbra.ans.net and in the body of your note, say: unsubscribe quattro-digest - - - - - - - - - - - - - - - - - - - - - - - - - For access to the web archives, point your browser at: http://coimbra.ans.net/quattro.html - - - - - - - - - - - - - - - - - - - - - - - - - ---------------------------------------------------------------------- From: "Graydon D. Stuckey" <graydon@apollo.gmi.edu> Date: Mon, 12 Feb 1996 16:26:56 -0500 (EST) Subject: Al rotors On Mon, 12 Feb 1996, Robert S. Cohen wrote: > STEADIRIC wrote- > >>Sure, less is better, but c'mon man! > >>You tryin' to tell me that the relative rotational mass of the prowler > >>brakes Vs that of the viper brakes accounts for the better braking *more* > >>than does the relative mass of the vehicle and relative amounts of swept > >>area? > > > >Yes I am, do the math....... Don't know the math, LEARN IT if your going > >to pontificate. I know it....... Graydon knows it........ Scott knows > >it......... > > FALLACIOUS ARGUMENT ALERT. > > I'm gonna pontificate. Where's my mitre? > > AHEM, Eric, the rest of us don't _ know_ it! > > It is not manifestly obvious to me how this can be the case. Perhaps you > could share the math with the rest of us....? > > Before you accuse me of being lazy, I've briefly discussed the problem with > a physicist here. the upshot of our admittedly naive investigation was that > aluminum rotors would probably make for somewhat diminished stopping due to > the specific heat of the (light) aluminum rotor vs the (heavy) iron rotor. > Decelerating at the same rate, the aluminum rotor will get 40% hotter. > > Al Fe > Density g/cm^3 2.7 7.86 > Sp. Heat J/(g*degK) .9 .44 > > with these numbers, I calculate that for equal volumes (we simply swap > aluminum for iron) the iron rotor will be 2.9 times more massive. for equal > masses, the iron rotor will heat 1 degK for each .48 degK the aluminum > rotor heats. 2.9*.48= 1.392. So, a rotor of Al equal in volume to the > original Fe rotor will be increase in temperature 40% more than the iron > rotor for a given deceleration (energy input). There. I did the math. > > regarding the kinetic energy of the rotors themselves, which I think is the > factor Eric is alluding to, it is (m w^2 r^2) I think, where m is the mass > of the ring, w is the angular velocity, and r is the radius of the > idealized ring. Frankly, I (waving my hands) think this will pale in > comparison the energy of a 3000 lb car travelling at 100 kmph or so. > > End of Audience. Get out of my basilica..... ;-) Robert, Glen, Eric, at al, I never meant this to be a big heated argument. I was merely stating what I heard from Team Prowler. I didn't do the test myself, nor was I in attendance when the test was done, so take it with a grain of salt, not a Congressional seal of approval. My point was that the ALuminum rotors reduce the rotating inertia of the wheel/rotor assemblies, and that has a profound influence on the braking of the car. How much is not open to discussion really unless you have real numbers to back you up. I don't, so I haven't really argued it. I would also point out that the rotors are NOT made of simple aluminum. They are a pretty exotic alloy (possibly even a composite) that takes this kind of abuse very well. I'd love to run the numbers, but being a lazy engineer, I don't have all the formulas memorized, and I would have to go back to my texts, and look up the formulas. Unfortunately I don't have time for that today. I have a sick Quattro sulking in the garage, and a little boy that wants to play :) Later, Graydon D. Stuckey graydon@apollo.gmi.edu Flint, Michigan USA '86 Audi 5000 CS Turbo Quattro, GDS Racing Stage II '85 Mazda RX7 GS 12A-leaning-towards-a-13B-soon ------------------------------ From: Gary Erickson <erickson@teleport.com> Date: Mon, 12 Feb 1996 13:32:12 +0000 Subject: Hella lights vs. PIAA (revisited) I remember the subject of the PIAA lights vs. the Hella Aux Low Beams coming up a week or so back. The clincher is that I'd rather save the money on the PIAA's and go for the Hellas. I understand that the Hella's were designed to be mounted on top of the bumper. Does anybody know if they can be mounted pendant-style from the bottom of the bumper? I know that I'll lose a little bit of the distance that way, but I've got the 100W high beams to make up that difference. Finally any sugggestions on how to best mount these suckers to the front of a 4K/GT series car? I'd like to try to get them mounted well enough that a minor run-in with some shrubbery doesn't re-aim them somewhere in the vicinity of Mars/Jupiter! Thanks, Gary ------------------------------ From: Robert Hines <hinesr@csa.delta1.org> Date: Mon, 12 Feb 1996 16:52:53 -0500 (EST) Subject: Low oil light I missed the origional post on the low oil warning light, but can tell you why mazda has this feature. When they first started importing the rotary enginer RX-2 and 3's the engines used a very small amount of oil for lubrication as a normal part of running. Therefore the oil had to be topped up periodically. The salespeople didn't want to tell their customers that the car used oil, which was also described in the owners manual, but thats seldom read. KSo they let their customer run the oil down to one quart low and then the metering unit quit dispensing oil to the rotors and heat and friction caused engine failure. Mazda bought a lot of ill will and then later a lot of factory rebuilds. cost hem millions. I was racing an RX-3 in GT-3 and had a dealer sponsorship at that time so had access to his back lot where a lot of customers abandoned their cars. We bought twelve of them and warranteed the motors over time and at the eleventh motor mazda said no more. We bought most of the cars for $25 to $50 each and sold them with minor repairs for $1000 to $1500. Just another form of sponsorhsip the way I saw it. Bob ------------------------------ From: "Al Powell" <APOWELL@agcom.tamu.edu> Date: Mon, 12 Feb 1996 15:57:44 CDT Subject: Re: Oil Level light? Bob D'amato wrote: > > OK, OK.....but afterall, it'z a rotary, and therefore contrary to the > > lawz of nachur and apple pie, right??????? (And all one has to do is > > state something with confidence and someone will find exceptions.... > > :-) > > > > wait wait wait!!! My snowmobile has a low oil warning light, and it isnt > rotary!! :) > > Bob Hmm. I'm beginning to wonder if Bob's snowmobile isn't the only thing in that family that's at least "one quart shy of a full crankcase........" :-) *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** Al Powell Voice: 409/845-2807 Ag Communications Fax: 409/862-1202 107 Reed McDonald Bldg. Email: a-powell1@tamu.edu College Station, TX 77843-2112 W3 page - http://agcomwww.tamu.edu/agcom/rpe/alpage.htm ***The PACK is back!*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ------------------------------ From: "Bob D'Amato" <Bob.Damato@snetel.com> Date: Mon, 12 Feb 1996 17:16:24 -0500 (EST) Subject: Re: Oil Level light? On Mon, 12 Feb 1996, Al Powell wrote: > > > > wait wait wait!!! My snowmobile has a low oil warning light, and it isnt > > rotary!! :) > > > > Bob > > Hmm. I'm beginning to wonder if Bob's snowmobile isn't the only > thing in that family that's at least "one quart shy of a full > crankcase........" :-) > Gosh.. thanks for the tip, Ill check the Audi tonight! :) (duhhh!) :) Bob ______ ___/ __ \______ ___ __ ___ ___ __ _\_\_____) / _ )___ / / / _ \/ _ | __ _ ___ _/ /____ (____) / _ / _ \/ _ \ / // / __ |/ ' \/ _ `/ __/ _ \ __ (_____) /____/\___/_.__/ /____/_/ |_/_/_/_/\_,_/\__/\___/ \____(___) bob.damato@snetel.com http://snetel.com/audi/audi.html The Southern New England Telephone Co. |Phone: 203-771-7081 Information and Technology Center |Fax: 203-773-3398 300 George St. New Haven CT 06510 |Pager: Dont count on it Drive Safe, Drive Fast, Drive a Quattro ------------------------------ From: "Bob D'Amato" <Bob.Damato@snetel.com> Date: Mon, 12 Feb 1996 18:51:35 -0500 (EST) Subject: Re: PROPELLER SHAFT 88 80Q On Mon, 12 Feb 1996, Pre-installed User wrote: > HELLO ALL DOSE ANY ONE KNOW IF YOU CAN GET THE RUBBER BUSING > THAT IS ON THE PROPELLER SHAFT ON A 88 80Q. THIS IS WHAT I WOULD > CALL A HANGER BEARING BUSHING ON A NORMAL SPLIT TYPE DRIVE LINE. > AS OF NOW THRU AUDI DEALER PARTS YOU CAN ONLY GET THE PROPELER > SHAFT COMPLEAT AT A PRICE OF ABOUT $750.00 NOT CHEAP. > Mr Pre-installed user... (hey, thats what your email says!) Last check you can only get the whole thing, not sure if they changed their policy, but that was the case on my friends 89 90Q not 6 months ago. Bob ______ ___/ __ \______ ___ __ ___ ___ __ _\_\_____) / _ )___ / / / _ \/ _ | __ _ ___ _/ /____ (____) / _ / _ \/ _ \ / // / __ |/ ' \/ _ `/ __/ _ \ __ (_____) /____/\___/_.__/ /____/_/ |_/_/_/_/\_,_/\__/\___/ \____(___) bob.damato@snetel.com http://snetel.com/audi/audi.html The Southern New England Telephone Co. |Phone: 203-771-7081 Information and Technology Center |Fax: 203-773-3398 300 George St. New Haven CT 06510 |Pager: Dont count on it Drive Safe, Drive Fast, Drive a Quattro ------------------------------ From: <Porsray%aol.com%NESystems@nes.com> (porsray) Date: Mon, 12 Feb 1996 18:49:59 -0500 (EST) Subject: RE: 1990 Coupe Heater Blower Extraction Forwarded to: ismtp[quattro@coimbra.ans.net] cc: Comments by: Ian Duff@Tech@NESystems Comments: I will second the observation about just how large a PITA it is to remove and replace the glovebox in a '90 Coupe, having done same installing a cell phone. Here's a tip - use one of those socket driver universal joint thingies on the two screws on the console side. Lying on your back with your feet draped over the back of the passenger seat makes visibility rather limited. A word of warning - don't catch your shirt on the power seat switches, or you may think your beloved Coupe is trying to kill you. Good luck. Call if you have trouble, or direct email for any other info. Ian Duff '90 Coupe Quattro, New Bedford MA 617.672.8460 (vmail, pages me during work week) -------------------------- [Original Message] ------------------------- I saw the following question and decided to address it. "Okay, I've searched the archives in hopes of finding some info on removing/replacing the heater blower motor in an Audi 90 with limited success. I've found good info on performing the operation on a 5K, but not a 90. I am hoping that since this replacement is fairly common that one of you folks who has already done it could give me some insight into the precedure... Tips/etc. I appreciate any info... Please email directly and I'll compose a how-to after I'm done for the archives... Thanks, George" WHAT? You are trying this and you don't even have a factory shop manual?? For shame, for shame!! The below procedure is from the manual, although they glossed over some "fun" parts. I have done this job, and it is not fun at all. The biggest problem was lack of room to pull the blower out of the plenum; it is blocked by the passenger side A/C fresh air duct. But in case you want to try it, this is the procedure: 1) Remove the flat black plastic panel located right above the passenger footwell underneath the dash. There are two screws at each end right at the bottom of the glove box door (6mm hex, if I remember). Unscrew them, then slide the plastic panel straight out into the passenger compartment. 2) Unbolt and remove the glove box. This is held in place by 4 hex bolts (two per side, under the vertical sides of the glovebox door). These are just difficult to get at; there is another one at the very top center of the glovebox that is near impossible to get at. With the bolts out, the glovebox can be removed by pushing to one side and pulling out the side mounting rails on one side; the whole box should then fall out. (Almost forgot: unclip the glove box light from its bracket first. 3) You should now be able to see the blower mounted into the plenum. Unscrew the various hex-head bolts and disconnect the two power lead wires. With a little wiggling, the blower should break loose from the plenum. 4) Unfortunately, removal of the blower is blocked by the paseenger side A/C-fresh air duct. I thought about removing it, but one look at the location of the mounting clips indicated to me if I ever got them loose, I'd never get them back on again. So, the blower came out using brute force and prying; fortunately, nothing broke. 5) The new blower went in with just as much fun as the removal. make sure you apply some weaterproof sealant to the circumference of the blower housing where it seals to the plenum. 6) Now, more fun: reinstallation of the glvoe box is another nightmare. Problem is trying to align up the nuts on the glovebox mounting rails with the holes in the insrument panel, place the two plastic trim pieces on the outside and align THEIR holes, then try to screw in the mounting bolts. This took about as much time as the blower replacement itself. I have owned my 1990 Coupe for about 5 years now, and have amassed almost 100,000 miles on it. I'll try to pass on my other "fun" experiences in the future. However, I love the car and won't sell it for anything else presently in its market category (am waiting for Audi to offer a A4 Coupe hatchback - fat chance - or the A4 Avant offered in Europe; probably by the time it comes over, though, it'll be available only with a wimp stick). Ray ------------------------------ From: Slprywheel@aol.com Date: Mon, 12 Feb 1996 19:03:39 -0500 Subject: Re: Set Konis where? Neil, I set my red Koni's at 2/3 hard. At first they were quite stiff(CD player skipped often) byt after 7000 miles I have to say that this is a good choice. They have seemed to loosen up a bit. I guess I should say that I do like to drive the car hard so I do not mind a bit harder ride. Hope this gives you a starteing point. JIM 87'5KTQ (red Koni's all around) ------------------------------ From: orin@netcom.com (Orin) Date: Mon, 12 Feb 1996 16:14:07 -0800 (PST) Subject: Re: Al rotors Another thing to consider is the thermal conductivity of the rotor ie. how fast it conducts heat away from the swept area. Aluminum conducts heat away a lot better than iron/steel and I believe this will more than make up for the lower specifig heat capacity. Orin. ------------------------------ From: Slprywheel@aol.com Date: Mon, 12 Feb 1996 19:52:54 -0500 Subject: AUDI SPORT STICKERS I hope this is proper etiquette for the forum, if it not just give me a subtle hint. Anyway I have just recieved a hundred Audi Sport stickers that I had made up for me. I would have bought fewer but that was the min. run the guy I used would do. Any way I am looking to get rid of some of them. They are 2.75"x 3.75" parallelagram with the 1995 Audi Sport design on them. They are three color (White background, red, black writing) they look almost perfect except that ther is no gray border(no one will notice). I would like to get $3.00 apiece. If you are interested please E-mail me direct (slprywheel@aol.com)as not to take up vabuable band width. Jim Finaly found some Audi Sport sticker,too many ------------------------------ From: Joel Cohen <joelc@hookup.net> Date: Mon, 12 Feb 1996 20:21:13 -0500 Subject: ABT Performance Upgrades I have a '96 A4 Quattro 5 Speed with the 2.8L V6 12 valve engine and am considering installing the ABT Performance Upgrade. The problem is that no two sources have given me the same(or even ballpark for that matter) regarding the resulting hp and torque increase resulting from such an upgrade. I would appreciate the answer or, in lieu thereof, a push in the right directikn regarding the resulting increase in both hp and torque. Please note, that I have already contacted JT Motorsport at (805) 579-9123. The informed me that the resulting hp and torque and 230 hp and 230 lb/ft respectively. Although these guys out to know, this seems kind of high to me. Any thoughts? Also, should I be considered and mods performed by Hoppen Motorsport? Laslty, what should this thing cost? I have been quoted prices between $3,500 US and $7,000 US. TIA, Joel ------------------------------ From: RDG51@aol.com Date: Mon, 12 Feb 1996 21:39:20 -0500 Subject: 83TQC handling I am interested in advice/opinions about how to make my car handle better. It has stock suspension, 80K miles, no rear antisway bar, and 7"Fuchs wheels with 205/60-15 tires. The quality I do not like is that "floaty" feeling-- body roll in turns, and diving when under hard braking. I am not looking to make this a track car, just a more sure footed road car while maintaining ride comfort. The Eibach springs I understand come in two varieties, progressive and linear, the progressive being too soft on the intial travel and too firm when wound up, the linear too firm in general or they lower the car too much. Can I achieve the ride I am looking for with just shocks? Konis vs. Bilsteins vs? Are gas shocks the way to go? I know there are alot of personal preference variables but I would appreciate any info that can be passed on. Thanks RDG51@aol.com. ------------------------------ From: John Karasaki <johkar@teleport.com> Date: Mon, 12 Feb 1996 18:47:34 -0800 Subject: Re: A/C problem/questions At 10:50 AM 2/12/96 -0700, you wrote: >So the questions are: >What leaked out? You lost your charge of refrigerant. The refrigeration lines have freon and oil in them. The oil lubricates the AC compressor. That's probably what you smelled. >What is the correct name for the radiator thing under the dash? That's the "evaporator." The radiator looking thing in front of your engine's radiator is the AC system's air cooled condenser. >I was planning on leaving the A/C intact and functional, but if >I have really screwed up in some high $$$ way, I might save >some weight. Refrigerant goes up in price daily now that it is not being produced. In the good old days you could buy a can of it to recharge you AC system yourself for only a couple of dollars. Now it's $$$/lb. Actually, it's illegal for you to fix your own AC system if you are not licensed for handling refrigerant. Best bet is to have it fixed. Regards, John Karasaki The Karasaki's, proud owners of AUDI automobiles 1981 Coupe 1982 TQC 1984 5000S Wagon 1990 V8 ------------------------------ From: John Karasaki <johkar@teleport.com> Date: Mon, 12 Feb 1996 18:47:31 -0800 Subject: Re: LIGHTS - 5000CSTQ At 09:35 AM 2/12/96 EST, you wrote: >Ernest, > >I just purchased 9004 halogen lamps that are 55/100 watts from J.C.Whitney. >These install without any modifications and give significant improvement to the >night time visibility. Been there, done that, had light switch problems. I suggest you install a relay if you plan on running the those bulbs in "hi". I had 100 watt bulbs installed in our '87 5kcst for exactly nine hours. "Sniff, sniff. You smell smoke?" Then dash lights went out. There has been much discussion on the list recently about the stock headlight switch not being able to handle the additional current draw. At the NW region picnic last year there were a few 5kq's there who had gone down the same path with the same frustrating results. In a nutshell, if you are going to run higher wattage bulbs in the DOT lights, modifications are required. Good luck. Regards, John Karasaki The Karasaki's, proud owners of AUDI automobiles 1981 Coupe 1982 TQC 1984 5000S Wagon 1990 V8 ------------------------------ From: Mason Bender <mbender@freenet.columbus.oh.us> Date: Mon, 12 Feb 1996 22:47:25 -0500 (EST) Subject: Anti-roll bars for 4000Q Dear Quattrophiles- I am writing to find out about experiences with changing the anti-roll bars on a 4000 quattro. I would like to use a larger bar up front, and install a small bar in the rear. My purpose is to reduce body roll while cornering, and dial out most of the understeer. I have looked in the archives, and found some articles, but nothing specifically pertains to the 4000q. I am looking to find out what people have done for a rear connection system. So far I have heard various stories: From one person who put a set of front control arms on the rear (will this really work?), to another person who welded the end of the link-rods to the control arms (seems pretty crazy to me). I am also interested to find out what size bars people have used. Has anyone made an adjustable rear bar? Your comments are very much appreciated. Mason B 4kcsq ------------------------------ From: ScottB2460@aol.com Date: Mon, 12 Feb 1996 23:25:03 -0500 Subject: Body parts The Mrs. conducted a 360 on ice the other day and kissed a 74 LeMans. The LeMans crumpled up while my baby had minor damage to the LF quarter panel. The claims adjuster came up with $1200 in parts/labor/paint. Are there parts vendors where I can try to get the paint and lens/headlight housings that will need to be replaced? I am trying to avoid a $2000 total cost between my job and the likely totalling of the LeMans. Anything over the 2 grand gives another "point" against me. I figure if it goes over that amount, I can try to go "aftermarket" with the paint and lens/headlight housings to keep it below that level. Appreciate any information. Scott 89 200tq ------------------------------ From: STEADIRIC@aol.com Date: Mon, 12 Feb 1996 23:56:12 -0500 Subject: Re: Hella lights vs. PIAA (revisited) >I understand that the Hella's were designed to be mounted on top of the >bumper. Does anybody know if they can be mounted pendant-style from >the bottom of the bumper? I know that I'll lose a little bit of the >distance that way, but I've got the 100W highbeams to make up that >difference. > >Finally any sugggestions on how to best mount these suckers to the front >of a 4K/GT series car? I'd like to try to get them mounted well enough >that a minor run-in with some shrubbery doesn't re-aim them somewhere >in the vicinity of Mars/Jupiter! I've got them mounted Pendant style on my 5KTQ and they work great.... In fact I don't even use my high beams anymore and they don't blind oncomming drivers. Try removing the lower grill and tucking the back of the lights in there, but if your running into shrubs and parking stones it's not going to re-aim the "vicinity of Mars/Jupiter" it's going to break the $35 lenses. So I guess the moral of this story is "don't run into them!" Later! Eric Fletcher '87 5KCSTQIA2RSR2B STEADIRIC@aol.com ------------------------------ From: STEADIRIC@aol.com Date: Mon, 12 Feb 1996 23:56:17 -0500 Subject: Re: ABT Performance Upgrades What does the kit include/Do?? With that info then I can help you out. Later! Eric Fletcher '87 5KCSTQIA2RSR2B STEADIRIC@aol.com ------------------------------ From: STEADIRIC@aol.com Date: Tue, 13 Feb 1996 01:40:18 -0500 Subject: Re: A/C problem/questions Actually Dave it sounds like you broke the A/C thermostat A $110 part at the dealer, Unfortunatly the only place you can get the part. I spent five days looking for a place that I could get it cheaper for my old '81 coupe. (Same A/C system) It's a little capilary tube that goes to a sensing bulb in the A/C Evaporator and the other end hooks onto the temp Adjuster slider in the A/C controls. It's easy (As Audi Climate Controls go) to change and takes about 30 min. Just my $1.05 Later! Eric Fletcher '87 5KCSTQIA2RSR2B STEADIRIC@aol.com ------------------------------ From: dieckeaw@plu.edu Date: Mon, 12 Feb 1996 23:12:40 -0800 (PST) Subject: "G'd out" 5k When I first joined the list several months ago there was a thread about a "G'd out" 5k. Lowered big time, neon, tinted windows, etc. I thought that would look rediculous at the time. I underestimated myself! I saw an '84 5k today on my way home. It had a neon license plate frame, was lowered several inches but had what looked to be 175/70-14 tires (stock size for our '73 100ls of yore) with wire hubcaps! boy did it look ugly! I always thought mini pickups and 80's american cars (the most common G'd car) looked rediculous, but that Audi was BAD! Just had to share this with 'yall. - -Adam ------------------------------ From: Jeremy R King <kingjer@eng.auburn.edu> Date: Tue, 13 Feb 1996 01:21:10 -0600 (CST) Subject: Al Rotors - The definitive answer (Looong) Here's a lesson on metallurgy/kinetics/heat transfer/fluid dynamics for anyone interested - subject to correction as needed. Glen, you're right on the money with one clarification (I'll get to that later). Eric, you're full of it. You must be using a solar calculator in moonlight to do your "math". Alan, very correct. The key to stopping a car from forward motion (ie possessing kinetic energy) is to somehow dissipate that energy. Remember, energy can neither be created or destroyed. Therefore we have to get it to change forms. One way would be to run the car into a wall or a tree or something, and share that kinetic energy with the wall and the little atoms in the metal of the car itself. Not good. So the way we do it without destroying everything is through FRICTION. Friction is the most important thing in stopping a car using brakes. There are two places this friction is important - one is between the rotor and pads, the other is between the tire contact patch and the road. If you think back to your classes (physics), a frictional force (in our case - stopping force) is equal to the normal force (normal as in perpendicular, not everyday) times the coefficient of friction. So, there are ONLY two ways to increase a car's stopping force. One is to increase the coefficient of friction. The other is to increase the normal force. Before somebody (Glen) jumps all over me on that one with, "What about swept area?" Easy - - to come up with a total stopping force on one wheel at the rotor, you must integrate the normal force at each point over the whole pad area. Thus the bigger the pad surface area is, the bigger the overall normal force will be. The first thing to look at is the rotor/pad interface. The rotor/pad's job is to overcome the rotation of the tire/wheel/rotor/hub/etc (everything that's rotating) period. The rotor/pad does not directly stop linear momentum of the car! So, Eric, you are correct in saying that a lighter rotor would reduce rotational inertia of the rotating mass. But you're dead wrong in saying that the mass difference from an aluminum rotor to an iron one will make a significant difference in stopping force due to reduced rotational inertia. This effect will be totally insignificant. Glen is right on the money saying that the wheel and tire have a much greater effect on this phenomenon. The one thing Glen left out is the fact that the tire also has a frictional force acting on it that wants to continue to rotate the wheel/tire/etc. This force is much greater than the rotational inertia of the rotational mass, and much much greater than the rotational inertia of the wimpy little rotor! So where does this frictional force on the tire come from. Simple - multiply the normal force on the tire (gee, would that be weight?!!! as in MASS times acceleration) times the coefficient of friction between the tire contact patch and road surface. Again, integrate the weight of the car over the contact patch - thus if the contact patch is bigger, you get more overall normal force. Also note here that the rubber compound of the tire plays a key role in coefficient of friction. So, the heavier the car, the larger the normal force for a given Cf and tire patch. Thus a larger frictional force trying to keep the tire/wheel/etc. spinning. Obviously, if you have a light car with really good brakes (high Cf), you can easily lock up the tires. This is because the normal force on the tires isn't big enough (small weight) to create enough friction to keep the tire spinning. OTOH with a heavy car and bad brakes, the tires probably won't lock up and the car'll take a while to stop. We all know that friction works through the generation of heat. Friction's job is to take kinetic energy and change it into heat energy. So now heat comes into play. At the rotors, heat can change the compound of the brake pads and thus reduce the coefficient of friction between the pads and rotor (fade). Here's where I think Aluminum makes its most important contribution. First of all, Aluminum is a softer metal than iron. Because it's softer, the coefficient of friction between an Aluminum rotor and a given set of pads would be significantly higher than the Cf between the same pads and an iron rotor. MORE STOPPING FORCE! This is, IMO, the main difference. Another advantage (though not nearly as significant) is Aluminum's higher specific heat. It was pointed out that an Aluminum rotor would get hotter than an iron one. Not so. The higher specific heat of the aluminum allows it to conduct heat AWAY FROM THE PADS to other parts of the rotor. This keeps the temperature at the pad lower than it would be with an iron rotor. BECAUSE Aluminum also dissipates heat to air a lot better than iron. So now the heat that is better conducted away from the pad is now better convected and radiated from the rotor into the air, which will carry this heat away. So why aren't all rotors aluminum? For one thing, aluminum is less stiff than iron. And the stronger alloys (7075, 7079) tend to be very brittle. But the main drawback is that aluminum has about a third of the cycle life of iron. It is very subject to fatigue. Since braking is a very cycle-intensive process, aluminum is not the best choice for your dependable, everyday commuter. Since the racing life of a part (on a race car) is very small compared to a passenger car, aluminum would be a viable alternative. Also, racing applications are tremendously sensitive to unsprung weight, where aluminum would provide yet another benefit. I think the answer lies with composite alloys, which would allow the benefits and help remedy the weaknesses. Sorry this was so long. I hope someone made it to the end. Jeremy R. King Senior Mechanical Engineering Student Suspension Team Leader - War Eagle Motorsports Formula SAE '86 VW Quantum GL5 Auburn University, Alabama, USA Hometown - Reidville, South Carolina, USA ------------------------------ From: STEADIRIC@aol.com Date: Tue, 13 Feb 1996 03:06:39 -0500 Subject: Re: Al Rotors - The definitive answer (Looong) >The first thing to look at is the rotor/pad interface. The rotor/pad's >job is to overcome the rotation of the tire/wheel/rotor/hub/etc >(everything that's rotating) period. The rotor/pad does not directly >stop linear momentum of the car! So, Eric, you are correct in saying >that a lighter rotor would reduce rotational inertia of the rotating >mass. But you're dead wrong in saying that the mass difference from an >aluminum rotor to an iron one will make a significant difference in >stopping force due to reduced rotational inertia. This effect will be >totally insignificant. Glen is right on the money saying that the wheel >and tire have a much greater effect on this phenomenon. The one thing >Glen left out is the fact that the tire also has a frictional force >acting on it that wants to continue to rotate the wheel/tire/etc. This >force is much greater than the rotational inertia of the rotational mass, >and much much greater than the rotational inertia of the wimpy little >rotor! So where does this frictional force on the tire come from. >Simple - multiply the normal force on the tire (gee, would that be >weight?!!! as in MASS times acceleration) times the coefficient of >friction between the tire contact patch and road surface. Again, >integrate the weight of the car over the contact patch - thus if the >contact patch is bigger, you get more overall normal force. Also note >here that the rubber compound of the tire plays a key role in coefficient >of friction. So, the heavier the car, the larger the normal force for a >given Cf and tire patch. Thus a larger frictional force trying to keep >the tire/wheel/etc. spinning. Jeremy, Nice try but.....We once did a test on the Camel Lights car for Hitco Ind. A huge supplier of Carbon, Metal Matrix, Al, and Cast Iron brakes for the racing community. What we found does not support your views but supports my views. Not only did the car stop faster (Shorter) with a lighter rotor (All other aspects normilized) but the car Accelerated FASTER with the lighter rotors..... On a race car the size of the lights car (2300lbs 585hp) the wheel weighs 8lbs and the tire weighs 12lbs for a total of 20lbs. a Iron Sephricone Rotor for this car weighs 16lbs (With Top Hat) 0-100mph came up in (Let me get out my notes...) in 8 Seconds with the gears that we had in for the test. With the Carbon Rotors That weighed 6lbs with Top Hat 0-100mph came up in 7secs......... In the same distance that the Iron rotors took to reach 100mph the Carbon rotor's helped the car get to 120mph...... Rotational Inertia plays a HUGE PART is this equation. If it did not we would'nt have spent $3500 Per Race on a 8lbs Clutch and flywheel. Ever lighten a cars flywheel?? HUGE Difference in Wrap up speed. Rotational Inertia once again. Do the math...... Later! Eric Fletcher '87 5KCSTQIA2RSR2B STEADIRIC@aol.com ------------------------------ End of Quattro Digest V3 #122 ***************************** To subscribe to quattro-digest, send the command: subscribe quattro-digest in the body of a message to majordomo@coimbra.ans.net. If you want to subscribe something other than the account the mail is coming from, such as a local redistribution list, then append that address to the "subscribe" command; for example, to subscribe "otheraddress": subscribe quattro-digest otheraddress@your.domain.net A non-digest (direct mail) version of this list is also available; to subscribe to that instead, replace all instances of "quattro-digest" in the commands above with "quattro".
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