Thorin Posted December 6, 2006 Report Share Posted December 6, 2006 Hi folks, only just recently discovered this forum and there's some very good info on here. I'll shortly be getting my alignment done and was after people opinions on here. I own a '94 MKIV Toyota Supra RZ (Twin turbo), it's on the stock j-spec bilsteins and springs and 245/40/18 front, 275/35/18 back tyres. In stock form the supra is a rather heavy understeery beast so I was looking for something a bit more 'planted'. 99% of the time (if not more) the car is to be used on the road though so I'm not after some race setup or something that's going to give excessive uneven tyre wear. The following info is from http://mkiv.com/techarticles/lance_alignment/index.html (pasted here for convenience) and the "Lance" set up seems well regarded... Mr. Lance W. Recommended Alignment This alignment is the result of experimentation with the factory numbers to improve road feel and to reduce inside edge wear on the rear tires that is common with the factory settings. These settings will add grip at the front and dramatically improve the feedback to the driver in the steering wheel. They will also reduce or eliminate inside edge wear on the rear tires, and I have gone as far as 24,000 miles on a set of Bridgestone S-02s with these settings. The car will still under steer slightly, but the aggressive driver will find much more predictable handling and significantly better feedback from the car. Obviously, these settings are still compromised for street use. Autocross, road race, and drag race competitors can use these as a baseline, but will probably require somewhat different settings to be competitive. 1. What is a Good Street/Lance W. Alignment? Front: * Camber - 1.0 degrees * Caster + 5.0 degrees * Toe 0.00 mm Rear: * Camber -1.5 degrees * Toe in (total) 1.00 mm (on 255/40R17 tires this rear toe equates to .090 deg, i.e. .045 deg per side) (on 275/40R17 tires this rear toe equates to .088 deg, i.e. .044 deg per side) The Front and Rear Toe are critical to tire wear, even small deviations from spec may cause unusual wear patterns or excessive wear. 2. What is the Stock Toyota Alignment? Front: * Camber - 0.5 degrees +/- 0.75 * Caster +3.5 +/- 0.75 degrees * Toe 0.00 +/- 0.080" (2 mm) Rear: * Camber -1.50 +/- 0.75 * Toe in (total) 0.120" (3mm) +/- 0.080" (2mm) To Calculate Degrees of Toe When Given mm of Toe: * Note that this is dependent upon the wheel diameter and tire diameter Formula: Calculate the Wheel + Tire Diameter (in mm) for the stock rear wheel + Tire Example: (2 * tire width * aspect ratio / 100) + (wheel diameter) = wheel + tire diameter (2 * 255mm * .4) + (17 * 25.4) = 635.8 mm Here the goal is 1 mm of total toe in. (This is 0.5 mm on the driver rear tire and 0.5 mm on the passenger rear tire.) We want to calculate the angle each side wheel + tire must deviate from a line parallel to the centerline of the car. arcsin(0.5 mm / 635.8 mm) = .045 deg .045 deg per side * 2 sides = .09 deg total toe in Now that sounds good to me, but a member on the mkivsupra.net forum has been very vocal about some other settings, and even states that the stock settings, and the Lance ones, are rubbish. The settings however make no sense to me (positive camber on the front??), but I'm no expert. Is he on to something? Settings follow... Thanks in advance for your comments, Michael. Quote Link to comment Share on other sites More sharing options...
scorps Posted December 6, 2006 Report Share Posted December 6, 2006 Hi Thorin....and welcome to WIM Im sure someone will be along shortly to answer any/all of your q's...as i dont have a clue Quote Link to comment Share on other sites More sharing options...
Noel Posted December 6, 2006 Report Share Posted December 6, 2006 Totally different suggestion.... but won't having extra wide tyres at the back cause under-steer too....? Quote Link to comment Share on other sites More sharing options...
Tony Posted December 6, 2006 Report Share Posted December 6, 2006 Hello and welcome to wim.... Your perception of the last report is totally correct... They are pants on the steer axis suggesting a real problem with cradle symmetry... Unless racing on an oval is your daily drive then positive over negative camber positions are not desired... nor is the displacement of the king-pins! The Lance settings are comfortable in my opinion, my question is this though.. if under-steer is not desired how would you want the car more planted? This is possible but direct involvement at the Geometry will not satisfy you. Quote Link to comment Share on other sites More sharing options...
Thorin Posted December 7, 2006 Author Report Share Posted December 7, 2006 Totally different suggestion.... but won't having extra wide tyres at the back cause under-steer too....? But I have larger tyres at the front too than the stock set up (235/255), but yes. Hello and welcome to wim.... Your perception of the last report is totally correct... They are pants on the steer axis suggesting a real problem with cradle symmetry... Unless racing on an oval is your daily drive then positive over negative camber positions are not desired... nor is the displacement of the king-pins!The Lance settings are comfortable in my opinion, my question is this though.. if under-steer is not desired how would you want the car more planted? This is possible but direct involvement at the Geometry will not satisfy you. Thanks for the reply. I've not had anyone else so far recommend the second lot of settings. I'm just after something a bit less understeery and more balanced really, while not so much as to send me oversteering into a tree, so I think my mind is made up on the Lance settings Another question while I'm here, anyone recommend anywhere to get my alignment setup done in or around the west yorkshire area? Quote Link to comment Share on other sites More sharing options...
Tony Posted December 7, 2006 Report Share Posted December 7, 2006 Totally different suggestion.... but won't having extra wide tyres at the back cause under-steer too....? But I have larger tyres at the front too than the stock set up (235/255), but yes. Hello and welcome to wim.... Your perception of the last report is totally correct... They are pants on the steer axis suggesting a real problem with cradle symmetry... Unless racing on an oval is your daily drive then positive over negative camber positions are not desired... nor is the displacement of the king-pins!The Lance settings are comfortable in my opinion, my question is this though.. if under-steer is not desired how would you want the car more planted? This is possible but direct involvement at the Geometry will not satisfy you. Thanks for the reply. I've not had anyone else so far recommend the second lot of settings. I'm just after something a bit less understeery and more balanced really, while not so much as to send me oversteering into a tree, so I think my mind is made up on the Lance settings Another question while I'm here, anyone recommend anywhere to get my alignment setup done in or around the west yorkshire area? The Lance positions are safe and a good starting position allowing you to develop the handling... I must say though few would recommend deviation from these settings without destroying the tyres. Quote Link to comment Share on other sites More sharing options...
The Gazman Posted January 5, 2007 Report Share Posted January 5, 2007 The Lance set-up will give you a nice safe understeer but if you want the car a bit more pointy without damaging tyres you might like to consider the following options. 1) What sort of ride height are you running and is the rear 10/15mm higher than the front? 2) To cure understeer and make the car more pointy consider the following. Front Caster=4.5 degrees Camber=1.5 degrees neg Toe= Parallel Rear Camber=1 degree neg Toe= 3mm overall toe in This should not have a detremental effect on tyres. Quote Link to comment Share on other sites More sharing options...
Suprash Posted January 12, 2007 Report Share Posted January 12, 2007 Hey Thorin, you wont go wrong if you get Tony to do it, he impressed me no end, not with just his work but his appreciation for cars...... [/hijack] Hi Tony, I can now post eventually.......thanks for the set up the other day, I will post in the newbie section soon.... [/hijack] Quote Link to comment Share on other sites More sharing options...
Tony Posted January 13, 2007 Report Share Posted January 13, 2007 Hey Thorin, you wont go wrong if you get Tony to do it, he impressed me no end, not with just his work but his appreciation for cars...... [/hijack] Hi Tony, I can now post eventually.......thanks for the set up the other day, I will post in the newbie section soon.... [/hijack] No problem.... Please introduce yourself and the car to wim.... (i have ) Well the car anyway! Quote Link to comment Share on other sites More sharing options...
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