Author |
Message |
phil randall
Experienced User Username: phil_randall
Post Number: 20 Registered: 8-2006
| Posted on Monday, 11 April, 2016 - 19:59: | |
about 3,000 miles ago i had the front geometry aligned on my 90' turbo R, since then it's had new front road springs so i thought it might be an idea to have it done again......but when i compare the readout sheet from the alignment shop the acceptable parameters are not the same as it shows in the workshop manual,....should i stick to the w/manual settings..? also has anyone had the rear geometry adjusted while the trailing arms are on the car ?... ie 4 wheel alignment in a workshop........taking the arms off and putting them in a jig seems a bit of overkill!!! thanks phil |
Carl Jones
Experienced User Username: carl888
Post Number: 20 Registered: 4-2013
| Posted on Tuesday, 07 June, 2016 - 12:21: | |
Phil, can you post the alignment report and I'll have a look for you. With regards to the rear, I am not aware the rear is in any way adjustable unless eccentric bushes are fitted to the trailing arms. |
Jean-Pierre 'JP' Hilbert
Prolific User Username: jphilbert
Post Number: 146 Registered: 9-2013
| Posted on Wednesday, 08 June, 2016 - 08:16: | |
Phil, Your new front springs will invariably be a bit taller than the old ones. Hence the ''standing height'' is modified. This will affect most of all camber, but also caster. Do you remember removog/adding/seeing any of those half-circular shims below the springs? Measuring standing eight is described in the workshop manual. http://rrtechnical.info/sz/05_sz.htm |
phil randall
Experienced User Username: phil_randall
Post Number: 21 Registered: 8-2006
| Posted on Wednesday, 08 June, 2016 - 17:49: | |
thanks, this alignment report was done before the new springs were fitted...if it still has similar settings i feel that the toe-in could be better, and the camber could be given a tad more negative angle....from what i understand from the manual, the rear can be adjusted, but only with the trailing arms removed from the car..i hope the image comes out the right size...cheers
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Carl Jones
Experienced User Username: carl888
Post Number: 23 Registered: 4-2013
| Posted on Wednesday, 08 June, 2016 - 20:35: | |
Phil, I can't quite see the figures on my screen, any chance you can send it to me directly? carljones@hotmail.sg |
David Gore
Moderator Username: david_gore
Post Number: 2066 Registered: 4-2003
| Posted on Thursday, 09 June, 2016 - 08:38: | |
Have enlarged original posted image - unfortunately the original image is too small to enlarge without losing sharpness.
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phil randall
Experienced User Username: phil_randall
Post Number: 22 Registered: 8-2006
| Posted on Thursday, 09 June, 2016 - 18:20: | |
factory camber setting says 0.5 degrees neg, + or - 30 mins. current actual setting is.. left -0 deg 17 mins right -0 deg 19 mins. factory caster setting...3 degs pos, + or - 30 mins current setting.. left +2 degs, 51 mins right +2 degs, 40 mins factory toe-in setting...12 mins, + or - 5 mins current setting... left 07 mins right 04 mins maybe this is helpful thanks |
Carl Jones
Experienced User Username: carl888
Post Number: 24 Registered: 4-2013
| Posted on Thursday, 09 June, 2016 - 20:58: | |
Phil, The factory settings seem to be very broad. 0.5 degrees negative front camber translates into 30 minutes negative (remember, 60 minutes per degree). So with the tolerances quoted of + or - 30 minutes, you could have 0 degree camber one side, and 1 degree negative on the other and still be within the factory recommendation. However your car only shows a front camber asymmetry of 2 minutes, or 1/30 of a degree. A slight difference in the paint thickness of the rim would account for a greater difference! You have approximately 1/3 of a degree negative camber on your front axle each side. Do remember that any alignment setting is a compromise and sometimes you need to experiment a little. For example, in my own case, I tend to drive quite briskly in corners, and that tends to wear the outside of the tyres. For this reason, I apply more negative camber to counteract wear. Whilst wear becomes even, straight line stability suffers slightly and tramlining increases. The factory figures will always give you an excellent starting point. It does seem however that your message suggests that the car does not drive as well as it did before, is that the case? Unless I've missed something, your report falls within the factory specifications you quote for all three parameters on the front axle. (Assuming the toe in figure is total toe NOT individual toe) |
Carl Jones
Experienced User Username: carl888
Post Number: 25 Registered: 4-2013
| Posted on Thursday, 09 June, 2016 - 21:01: | |
(Assuming the toe in figure is total toe NOT individual toe) I mean the toe figure you quoted from the factory, obviously the toe figure on the printed report is individual toe. |
phil randall
Experienced User Username: phil_randall
Post Number: 23 Registered: 8-2006
| Posted on Thursday, 09 June, 2016 - 23:37: | |
Carl, as far as i can see in the manual the total toe-in is 12 mins. so as you say, all settings are within tolerance...or were before the new springs were fitted, as Jean Pierre suggests, they might of increased the ride height with a knock on effect to the steering. your comment about paint thickness on the rims probably puts things into perspective...i'll have it checked again on hunter equipment...if it's within tolerance it will stay as it is! thanks for your help phil |
Jean-Pierre 'JP' Hilbert
Prolific User Username: jphilbert
Post Number: 147 Registered: 9-2013
| Posted on Friday, 10 June, 2016 - 01:25: | |
@ experimenting: I found that a bit more negative camber on the front eliminates all understeering. Car becomes a heavy oversteer'er, like a drift car. I prefer that to understeer! ...wish me all-time dry roads! |