mr2-digest Wednesday, 27 December 1995 Volume 01 : Number 074 Suspension deflection Rear Suspension Deflection check engine light code 91-92 Rear Suspension Toe-out Rear suspension toe-out deflection Bad Christmas filters engine temp gage operation MkII Headlights emergency brake cables track-control arm CD Players... Stickers... Sender: owner-mr2 Fuel Injector O-Rings ---------------------------------------------------------------------- From: uunet!interserv.com!kca Date: Sat, 23 Dec 1995 23:35:06 -0800 Subject: Suspension deflection Alright all of you Einstein-Math Wiz types, here's a little problem for you: Many people have voiced concerns about the 91-92 rear suspension toeing out on compression so . . . What is the formula for finding the maximum deflection angle that can occur when the rear suspension is compressed to full deflection (i.e. trailing arm is parallel to the ground)? I believe I have figured it out, although I haven't punched any real measurements into it yet. What can you come up with? The reason this comes to mind is that after considering lowering my turbo, I realized that some of the toe-out tendancy will be reduced, and the alignment will need to be changed to compensate. From this I figure the handling benefits are two-fold: stiffer springs and lower roll center = less body roll, and the suspension is closer to toe-in during compression like on the 93+s. Hence, why bother upgrading to the revised 93+ suspension if the 91-92 MK2s can be shifted to toe-in under compression by lowering. (I have doubts.) >From this, on a stock height 91-92 MK2: If I lower it 2", how much have I reduced the toe-out deflection of the rear suspension? It's a simple problem if you try to keep in mind that three things will always remain constant: The trailing arm length, the A-arm length, and the distance between the mounting points of these on the sub-frame. Remember not only the rear suspension mounting points were revised on the 93+ models. It was lowered 1" as well. Kip Anderson 91 Turbo kca@interserv.com ------------------------------ From: uunet!interserv.com!kca Date: Sun, 24 Dec 1995 10:45:12 -0800 Subject: Rear Suspension Deflection Alright, aside from the fact that I don't an A-arm from a control-arm here's a follow up to my earlier post on toe-out deflection for the 91-92 MK2 rear suspension: My not so exact measurements gave me a trailing link length of 18.5", a control arm length of 10.0", and a trailing link angle of 10 degrees from horizontal at the stock ride height. >From the previously mentioned constants and the trailing link angle I have figured the maximum toe-out deflection to be .28" rearward and 1.6 degrees when the trailing link moves to the 0 degree position. I have also recomputed the numbers assuming a 2" suspension drop: The trailing link angle at rest is now reduced to ~3.486 (No I didn't measure it to this precision. I am carrying through computations for the purpose of maintaining calculation accuracy.) Maximum toe-out deflection is now reduced to .2 degrees and .03" rearward. This makes a difference of 1.4 degrees and .25" of deflection. This should make a significant difference in the handling of the early MKIIs by making handling more stable when an error in cornering judgement has occurred. SUMMARY: If you plan to lower your 91-92 MKII 2", you probably wouldn't want to bother upgrading to the 94 suspension parts because the toe-out tendancy of the rear wheels will be negligeable at the new ride height. P.S. If you figure out how I got these deflection numbers, I would like to know how you did it since my math-feeble mind struggled for over an hour to get the (hopefully correct) formula. I'll post the fromula in a couple of days. Kip Anderson 91 Turbo kca@interserv.com ------------------------------ From: uunet!touch.micron.caltech.edu!charlesg (Charles Grosjean) Date: 25 Dec 95 01:39:44 GMT Subject: check engine light code First, Merry Christmas! Second, here I am 400 miles from home (and more importantly my service manual) and my check engine light comes on. Shorting TE1 and E1 gives 7 fast blinks followed by a single blink after a pause => code 71? If that is the case, and this is an EGR problem (no, I'm not psychic, I just scanned the archive), then is it okay to drive 400 miles before fixing it? Also, am I most likely a victim of the cracked EGR tube (this is a 91T) and if so, how much will that set me back. Thanks, Charles Grosjean charlesg@touch.caltech.edu ------------------------------ From: uunet!interserv.com!kca Date: Mon, 25 Dec 1995 11:14:27 -0800 Subject: 91-92 Rear Suspension Toe-out Have you been contemplating upgrading the rear suspension of your 91-92 MkII to the 93+ parts? Are you bothered by the tail-happiness of the car on uneven road surfaces? Have you been considering lowering the car? If you've answered "yes" to at least one of the above here's some good info for you: According to a Road & Track magazine review of the 93 Turbo: The suspension was revised to eliminate much of the toe-out problems inherent to the rear suspension of the 91-92 models. Toyota also lowered the car 1" for the 93+ models. Well here's the deal! If you lower your car, the toe-out induced oversteer that makes these cars so tricky to drive at the limits will be greatly reduced if not eliminated! The reason is this: Toyota designed the pre 93 MkIIs with a trailing link that angles down from the frame to the control arm. This created the effect of deflecting the control arm to the rear as the trailing link approaches the horizontal position under compression. The result of this is toe-out on compression (bad). On the 93+ models Toyota realized an easy fix for this and redesigned the trailing link to remain near horizontal in the resting position. Under compression the control arm end of the trailing link is raised above the frame end, deflecting the suspension forward, thus creating toe-in (good). Following this do far? The point of all of this??? If you intend to use lowering springs on your pre 93 MkII, you reduce if not eliminate the factors that would make changing to the post 93 suspension parts beneficial. (The following numbers were obtained via an oh-so-accurate precision calibrated Stanley tape measure so YMMV.) The numbers, using a control arm length of 10", a trailing arm length of 18.5" and trailing link angles (calculated) of 10.0, 6.6, 3.5, and .39: Maximum toe-out deflection (degrees/inches) Stock height (10 degrees) 1.6/.28 Lowered 1" (6.6 degrees) .7/.12 Lowered 2" (3.5 degrees) .2/.03 Lowered 3" (.39 degrees) 0.0/0.0 (not numerically significant) So to summarize this report: If you intend to lower your car 1", you will still be getting some toe-out oversteer, but it will be noticeably reduced. Your car will also be the same height as a 93+ MkII. If you lower your car 2", you will still be getting some minimal toe-out, but it is likely to be unoticeable at only .2 degrees. You may actually get toe-in assuming the suspension can travel that far. At 3" down, don't expect toe-out to be a problem because it won't be, but your kidneys will probably hate you. For my purposes I intend to lower my car 2" to get the maximum significant toe-out reduction (I doubt I'd notice the difference between 2 and 3) and maintain a ride quality that will be tolerable. Remember: This is really only 1" lower than a stock 93+. If you are wondering how I calculated these numbers, try to figure it out for yourself. My math-feeble mind struggled too long on this to come up with the simple formulas I used, so I could be wrong. I'll post my formulas to the list in a few days. Does anyone want to chance figuring out the 93+ deflection numbers? (Sorry if this appears to be a re-hash of earlier posts, but I think they disappeared into the "big nothing" when I sent them yesterday.) Kip Anderson 91 Turbo kca@interserv.com ------------------------------ From: uunet!interserv.com!kca Date: Mon, 25 Dec 1995 16:53:52 -0800 Subject: Rear suspension toe-out deflection Drat!!! I have uncovered an error in my calculations. I had previously posted that the max-toe-out deflection for the stock rear suspension of the 91-92 MkIIs is 1.6 degrees. This is incorrect. The real defelection number is 1.5 degrees. Just goes to further grind in the point a high school physics instructor of mine tried to instill in his students: If you write every number of every step in a calculation down on paper, it is a lot easier to confirm the results of the computation and track down errors. Kip Anderson 91 Turbo kca@interserv.com ------------------------------ From: uunet!pitt.edu!spatel (Sanjay Patel) Date: Tue, 26 Dec 1995 03:59:50 -0500 (EST) Subject: Bad Christmas Well less two weeks after getting my '93 MR2-T it has been in it's first accident. Some dufus ran into the side of the car at a stop sign. The damage is above the driver's side rear wheel, there is a signifcant denting above the wheel, the molding is cracked, the rear light assembly was also cracked and alot of paint was scraped away. The guy was driving a Chevy Starcraft van which of course had no damage to his bumper whatsoever. It was totally his fault but I can kind of understand why it happened.. The stop sign is at a T where there are a lot of trees and you almost have to drive past the sign to see the oncoming traffic, but this guy was in a hurry to get to a Christmas celebration and probably didnt take the time to look. This is a real Christmas bummer. Certainly not the worst Christmas ever but bad enough. Since this is the first accident i've had on a new car, what should I look for in the place to do the repairs? The dents are not that major, but the paint scrapes/scratches are going to require that a good paint-job is done. ------------------------------ From: uunet!reston.ans.net!enger (Robert M. Enger) Date: Tue, 26 Dec 1995 13:18:56 -0500 Subject: filters I called the local Toyota dealer's parts department and had them run the number 90915-03004. They said it is replaced by number 08922 02002. I asked him what it was, and he said an oil filter for use on some turbo engines, the MR2 and maybe something else. They had 22 in stock, so presumably it is a good part-number. Bob ------------------------------ From: Kerry Wood Date: 26 Dec 95 22:52:31 EST Subject: engine temp gage operation To All: Several on this list have noted that turbo engine performance is improved during cold weather. Have noted same conditions in the "sunny" South w/ ambient temps running in the low- to mid-thirties (that's degrees F for those of you outside the US) these days. [Where is global warming?;-)] Not surprising. Note that Lee Hurley who ran dyno tests for me stated that engine temps could be dropped as much as 15 degrees F on a very hot race track by running the heater wide open on the MR2 turbo, thereby improving performance by a measurable margin. [This assumes *you* can stand the heat!!] Also, consider all the posts to this list concerning lowering charge temps to increase power...but...have any of you noted operation of the temp gage in cold weather? The gage is marked off in 17 increments/18 spaces between the wide white bar at "cold" and the wide red bar at "too hot". Normally, my gage runs at the 8th mark when at full operating temp. Starting up on a cold morning, I usually push the heater lever to full hot, but one morning I didn't remember to do this until the gage had just reached the 8th mark. Since it was abt 20 degrees outside, I immediately pushed the lever to full hot and...noted that the temp gage immediately dropped 4 marks! Did the same thing the next morning w/ same results. The question(s) is/are - what is "normal operating temp" in degrees F? What number of degrees is represented by each mark or space on the gage? The service manual states that the engine is equipped w/ a 180 degree F thermostat but other information indicates that the PCME recognizes 194 degrees F as actual operating "normal". This would seem to make sense on the surface, but which is temp is really "normal"? What temp is "overheating"? Any info/comments will be greatly appreciated. Thanks in advance. Kerry Wood 93T Black (mildly modified) ------------------------------ From: Kerry Wood Date: 26 Dec 95 22:52:33 EST Subject: MkII Headlights To All: Like some of you on this list, I find the MkII's headlights to be anemic and would like to change out to much higher than the US stock 65/35 watt sealed beam units...but... After reading all the stuff on the digest and referring to Mark Bosma's addition to the web archive, then going to my trusty dealer w/ the part number posted there, contacting several performance parts suppliers looking for conversions and/or higher wattage sealed beam units and finally calling the US Toyota support line w/ the part number (what a trip, 4 hrs to get thru - although they were very courteous when I did get thru)...the info I got is - "You can't get here from there - no such part number - no such conversion - never sold that way." Well, BAH! HUMBUG! Did get the phone number for Toyota Australia from US Toyota and, if necessary, will order upgrades from Australia assuming they will fit, but surely there is a way to upgrade the stock units here in the US!!?? Remember somebody stating that they had a catalog offering a number of Japanese parts available here in the US. Would this catalog, assuming I remember correctly, list the upgrades? Any help w/ this upgrade will be really appreciated. Thanks. Kerry Wood 93T Black (mildly modified) "The more tech support lines I call, the more I like my dog!" ------------------------------ From: Charles Reed Date: Tue, 26 Dec 1995 16:30:54 -0500 (EST) Subject: emergency brake cables HELP! The dealer just told me that both of my cables are shot and need to be replaced. The cables themselves are $51 but labor is $230! Does this sound right to any of you. I'm slated to have the job done on Friday so if anyone out there has had this done before, plaese e-mail me directly at: st803cwk@dunx1.ocs.drexel.edu Thanks! Chuck 92MR2 NA 51K miles BTW, my wife gave me a gear shift boot for Xmas. She said it was only $23 at the dealer, but they need to know the year and *run number* of my car. Does anyone have any idea why? I did'nt think that there were any running changes in the 92 model. ------------------------------ From: uunet!ukonline.co.uk!david.cole Date: Wed, 27 Dec 1995 07:14:00 GMT Subject: track-control arm Hi All, Help is needed. Can anyone mail me a diagram and the correct procedure for removing and replacing the "track-control arm" for the front wheels? ('89 MkI) Also needed, ideal wet weather tyre pressures (front and back) If I keep the front tyres as standard, by what width can I increase the rear ones? How much extra grip will this give to the back end? Dave '89 MK1 81K ____________________________________________________________ |Reply to: | | | |David Cole david.cole@ukonline.co.uk | |Satellite Times Fax: (0181) 677 8223 | |Radio & Listings Sub-Editor | |23 Mitcham Lane | |Streatham, SW16 6LQ | |____________________________________________________________| ------------------------------ From: Tom Harrington Automation Date: Tue, 26 Dec 1995 23:44:06 -0800 (PST) Subject: CD Players... My cd-player stopped working... (period) If I put in a CD it takes the cd, but it does not sound like it spinns the cd up to speed. I looks like the "rotation motor?" is shot, or not working for that matter. Once or twice I saw the little "green" light that says "DISC" (or something like that).. you know the one that turns on when you put a cd in. Well it was "RED" It is not always red, just 1 or 2 times. My local toyota swindler/dealer says for $85 dollars they can try to fix it. If it costs more, then they will contact me. Problem is that there is a 3-4 week wait for the repair once they remove it. This means a month with out radio or tape. Has anyone else had this problem. I've thought of removing it a seeing if a wire got loose. Any Ideas? Ohh... It is the 3 in 1 unit in a 1991 MR2 Turbo.. 93K miles... Tom.... =========================================================================== I am Barney the Borg....Sesame Street will be assimilated! - --------------------------------------------------------------------------- Thomas Harrington, NCNE -- Las Vegas-Clark County Library District -- | Internet tomh@lvccld.lib.nv.us | Autocrossing, the only way to WWW Coming Soon... | learn to drive. Telphone 702.733.6260 | Fax 702.732.7271 | Note: NCNE - Non-Certified Network Engineer =========================================================================== ------------------------------ From: Tom Harrington Automation Date: Tue, 26 Dec 1995 23:47:33 -0800 (PST) Subject: Stickers... Ok... I missed all the talk about these stickers... but is there a WWW page with a picture of the stickers? Tom =========================================================================== I am Barney the Borg....Sesame Street will be assimilated! - --------------------------------------------------------------------------- Thomas Harrington, NCNE -- Las Vegas-Clark County Library District -- | Internet tomh@lvccld.lib.nv.us | Autocrossing, the only way to WWW Coming Soon... | learn to drive. Telphone 702.733.6260 | Fax 702.732.7271 | Note: NCNE - Non-Certified Network Engineer =========================================================================== ------------------------------ From: uunet!ukonline.co.uk!david.cole Date: Wed, 27 Dec 1995 19:19:39 GMT Subject: Sender: owner-mr2 Hi All, Help is needed. Can anyone mail me a diagram and the correct procedure for removing and replacing the "track-control arm" for the front wheels? ('89 MkI) Also needed, ideal wet weather tyre pressures (front and back) If I keep the front tyres as standard, by what width can I increase the rear ones? How much extra grip will this give to the back end? >From what I can gather, you guys in the States, race MR2's, does anyone have anything on video that they could mail to me? I'll happily pay for any costs... Dave '89 MK1 81K ____________________________________________________________ |Reply to: | | | |David Cole david.cole@ukonline.co.uk | |Satellite Times Fax: (0181) 677 8223 | |Radio & Listings Sub-Editor | |23 Mitcham Lane | |Streatham, SW16 6LQ | |____________________________________________________________| ------------------------------ From: uunet!ccmail.ceco.com!PRADEGA Date: Z; 20 Dec 95 11:00:38 CST Subject: Fuel Injector O-Rings I am reconstructing my intake manifold on my 85 MK1 NA and would like to know if anyone has replaced the o-rings on the fuel injectors, are these special as in resistant to degradation from fuel or can they be picked up at any hardware store? Thanks in advance. George ------------------------------ End of mr2-digest V1 #74