|Theory||reprinted from Grassroots Motorsports magazine|
|From: Damien Shulock
Tuesday, December 22, 1998 12:43 PM
Take 1: 205/60-15" Goodyear Eagle GT+4 (SPG 5.5"x15" wheels) and stock 1986 suspension w/ Group 6 springs.
Camber LF -.7° RF -.8° LR -.6° RR -.7°
Caster LF 1.9° RF 2.1°
Toe LF .05" RF .05" LR .10" RR .08"
Cross Caster Front -.2°
Total Toe Front .10" Rear .18"
Take 2: 205/50-15" Pirelli PZeros (SPG 5.5"x15" wheels) and stock 1986 suspension w/ G6 springs.
Camber LF -.9° RF -1.0" LR -.6° RR -.6°
Caster LF 2.7° RF 2.5°
Toe LF .05" RF .05" LR .06" RR .10"
Cross Caster Front .2°
Total Toe Front .10" Rear .16"
Take 3: 205/50-16" Falken GRbetas (Aero 6.5"x16" wheels) with 1988 suspension, including front hub/brake assemblies, and entire rear axle, same G6 springs.
Camber LF -1.2° RF -1.2" LR -.5° RR -.4°
Caster LF 2.0° RF 2.4°
Toe LF .03" RF .03" LR .11" RR .12"
Cross Caster Front -.4°
Total Toe Front .06" Rear .23"
I wasn't really impressed with 1, but that may be due to the weak tires that were on it at the time. The lack of traction caused a lot of skittishness that the alignment could not remedy.
2 was the best driving of the three, with best on-center road feel and intuitive turn-in. When other people first drove the car they were constantly cutting corners and overshooting lane changes, because the car reacted *now* to steering input. Highway stability and tracking was very good. Once again, tires make a big difference and certainly the PZeros contributed to the great handling.
3 is my current set up, and it has all the great handling of 2, but somewhere along the way I lost the great on-center tracking. There is some wandering with ruts, concrete joints, cross winds, etc. and it requires your attention to keep it in line. I Don't know what influence the GRbetas are having, although I am very impressed with cornering grip and braking performance.
|From Chip Lamb
Friday, December 18, 1998 7:06 PM
|Excessive negative camber wears tyres incorrectly, and too much caster is fine for highway speeds but around town will wear suspension joints. Leave the toe at zero. With that kind of negative camber setup, the car is touchy enough.|
|From: James Fox
Friday, December 18, 1998 1:08 AM
|1 degree negative camber
2.75 degrees castor
just a pinch of toe-in
|From: Chip Lamb
Friday, December 18, 1998 12:56 AM
|.5 - 1.0 negative camber
2.0 - 2.5 positive caster
|From: Shulock, Damien
Tuesday, June 16, 1998 11:04 AM
|Camber -0.9 -1.0
Caster +2.7 +2.5
Toe In .05" .05"
|From: Rodger B Carter
Thursday, May 07, 1998 11:19 AM
|What a difference! It feels like a totally different car!
It is hard to describe - but something about the way it tracks and how
it returns to center is much better.
Anyways, here is what I gave the alignment guy:
SAAB 900 Euro Spec Alignment
Caster + 2.5 to + 2.7 degrees
Toe-in "just a touch" - the smallest amount possible measured to Zero
|From: Larry West
Sent: Tuesday, February 17, 1998 1:33 PM
|Wear on the outside edges of the front tires is normal for a Classic
Saab 900 with stock alignment driven in any sort of 'spirited' fashion.
The stock camber is + 0.5 degrees - that's top of tires leaning OUT.
Many of us here (myself included) use - 0.5 degrees of camber (tops of tires leaning IN) as a starting point for future alignments. This helps to keep the inside of the tires on the road in turns. It also helps the car track in turns.
|From: Ywan Mason
Friday, December 05, 1997 11:19 PM
|Road crown is usually off set by giving 1/2 degree difference in caster readings, giving the highest positive caster to the low side of the road (depending which side you drive on) but this is not done in race alignments. Ever seen a crowned track? The front end alignment man at one of the dealers I worked for always set Saabs with very little toe in, this helped with their tendency of wearing edges off tires.|
|From: Larry West
Friday, May 02, 1997 9:44 AM
|Camber: 0.5 degrees *negative*
Caster: 2.75 degrees positive
Toe: 0 (zero, noll, nada, zip)