hengti 2 Posted March 1, 2009 (edited) does anyone know what all of the measurements on a geo printout mean? i'm ok with the basics (caster, camber, toe) and am wondering about the following: - first one will be easy for someone - most of the readings are in the format [ 1deg 23' ] - i probably should but haven't ever really understood how this works - presumably it's degrees, but what's the '23 feet' about?! - what's 'thrust angle'? (reading of -0deg11') - what's 'set back'? (front = 1mm; rear = -5mm) - what's 'track width diff'? (51mm) - what's 'wheel base diff'? (6mm) i've only added the actual measurements incase it helps identify what they might relate to any help would be most appreciated! ed. this is a Protyre printout, if that makes any odds Edited March 1, 2009 by hengti Share this post Link to post Share on other sites
jplautomotive 0 Posted March 1, 2009 does anyone know what all of the measurements on a geo printout mean? i'm ok with the basics (caster, camber, toe) and am wondering about the following: - first one will be easy for someone - most of the readings are in the format [ 1deg 23' ] - i probably should but haven't ever really understood how this works - presumably it's degrees, but what's the '23 feet' about?! - what's 'thrust angle'? (reading of -0deg11') - what's 'set back'? (front = 1mm; rear = -5mm) - what's 'track width diff'? (51mm) - what's 'wheel base diff'? (6mm) i've only added the actual measurements incase it helps identify what they might relate to any help would be most appreciated! ed. this is a Protyre printout, if that makes any odds - first one will be easy for someone - most of the readings are in the format [ 1deg 23' ] - i probably should but haven't ever really understood how this works - presumably it's degrees, but what's the '23 feet' about?! its not feet it means minuites 1 deg 23 mins - what's 'thrust angle'? (reading of -0deg11') cant remember - what's 'set back'? (front = 1mm; rear = -5mm) wheels set back across the axle - what's 'track width diff'? (51mm) difference in track width front to rear - what's 'wheel base diff'? (6mm) difference left to right wheel base in your case 1 mm plus 5 mm jonny Share this post Link to post Share on other sites
hengti 2 Posted March 1, 2009 grand - thanks a lot for that i've just quickly Googled minutes - is that as in a proportion of 60? so 1deg30' = 1.5deg? ok with track width and wheel base differences now, but still a little confused about set back - sorry to be a pain, but are you able to explain that in any more detail? (if anyone else were able to confirm what thrust angle is, i'd be fully enlightened!) Share this post Link to post Share on other sites
engine killer 5 Posted March 2, 2009 found this http://autorepair.about.com/cs/generalinfo/a/aa012201a_2.htm Set Back: The amount by which one front wheel is further back from the front of the vehicle than the other. It is also the angle formed by a line perpendicular to the axle centerline with respect to the vehicle's centerline. If the left wheel is further back than the right, setback is negative. If the right wheel is further back than the left, setback is positive. Setback should usually be zero to less than half a degree, but some vehicles have asymmetrical suspensions by design. Setback is measured with both wheels straight ahead, and is used as a diagnostic angle along with caster to identify chassis misalignment or collision damage. The presence of setback can also cause differences in toe-out on turn angle readings side-to-side. the internet is so amazing! Share this post Link to post Share on other sites
hengti 2 Posted March 2, 2009 that's a v handy link - explains thrust angle as well thanks chaps Share this post Link to post Share on other sites