Actual ISF Alignment Spec, not just "ranges" from alignment rack? Anybody?
#16
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#17
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the spec is for toe IN.. but a little toe out will help the car turn in a bit better but i dont think its worth the slight instability over uneven roads if you DD it.. as you can see in the document is states " TOE-IN ( TOTAL)" , also look at the ilustration it shows toe in.. most oem specs are for toe IN so the car dosnt wander on uneven pavement.. the oem wheel/tire package turns in pretty well for a FAT car..
Last edited by D2M; 08-21-10 at 03:06 PM.
#18
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While the spec says toe in, the cars are typically delivered with toe out which is why so many are complaining about inside edge wear from the factory.
Reading the spec it's pretty clear you can go from 1.84mm toe out to 2.16mm toe in and be within factory specs.
So calling it a "toe in" spec is just semantics.
FWIW, your car will turn in better with toe out on the front and toe in on the back. That's what I meant by my post, and anyone setting up the car for the track will want about 3mm toe out in the front and 3mm toe in at the back. Neither are very good for tire life though.
Reading the spec it's pretty clear you can go from 1.84mm toe out to 2.16mm toe in and be within factory specs.
So calling it a "toe in" spec is just semantics.
FWIW, your car will turn in better with toe out on the front and toe in on the back. That's what I meant by my post, and anyone setting up the car for the track will want about 3mm toe out in the front and 3mm toe in at the back. Neither are very good for tire life though.
#19
So i just replaced all 4 tires because my driver front had really bad camber wear. If i don't track the car can i just 0 it out or should i stick with the factory specs? I also just purchased RR USRS as well if that dictates anything.
#21
I was going to just 0 it out after i install bushings. Is that not recommended?
#22
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-Mike
#23
Sorry, I didn't mean to imply that was a bad idea.. Admittedly, I'm far from an alignment expert. My comment was based on what lobuxracer said about the range for "factory specs", and my own experience from my two previous alignments (after installing LCA bushings, then Penkse coilovers). Both times, I just let them do their thing. They know I track the car at this particular shop (they're motorsports enthusiasts as well), so I trusted their judgement and have been satisfied with the results. In hindsight, I guess my recommendation is pretty much what you plan on doing. Starting at 0 as a baseline and adjusting as needed based on handling & tire wear seems like a solid plan.
-Mike
-Mike
#24
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+1. If your goal is even wear, zero toe is where you need to start. If you are looking for mechanical performance, toe out 1 or 2mm is where you start knowing you will be sacrificing tire life for the improved turn in.
#25
Thanks, I don't track my car so ill probably start at 0 and adjust from there if needed.
#26
Revving an old thread and read through this one and others. I mainly daily drive mine and will be doing a 3,000 mile road trip soon (if I get back state side on time). Just wanted to get your opinions on it. Recently had suspension work done via list below.
- Tokico Blue struts
- Swift Springs
- RR Racing USRS control arm bushing kit
- SPC Front adjustable upper ball joints
- Proforged Front lower ball joints
- SPC Rear adjustable camber arms
- Tokico Blue struts
- Swift Springs
- RR Racing USRS control arm bushing kit
- SPC Front adjustable upper ball joints
- Proforged Front lower ball joints
- SPC Rear adjustable camber arms
#27
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It should drive fine and with a 3000 mile trip you should measure your tread depth and track it across 3 places on all 4 tires. As others stated, once you have the *as left* camber and toe, now you monitor for wear and adjust toe and pressure to find the balance needed for how it is used.
FWIW fully adjustable cars set to drive nice on flat and/or crowned roads typically run the right side with -0.1 to -0.3° more negative camber and even +0.4 to +0.8 more caster on the right than the left and drive great on flat or crowned roads. So don't worry about it matching if drives good and you can mitigate wear with toe and pressure changes.
Do keep in mind the repeatability of the machines and human are 0.1° typically. We see it all the time on non-adjustable suspensions.
Not apples to apples but the 350 calls for:
35 front / 38 rear and at those pressures the front eats the edges and the rear blows the center out.
So its running 40 PSI front and 34 PSI rear to hopefully get even wear across the whole tire.
FWIW fully adjustable cars set to drive nice on flat and/or crowned roads typically run the right side with -0.1 to -0.3° more negative camber and even +0.4 to +0.8 more caster on the right than the left and drive great on flat or crowned roads. So don't worry about it matching if drives good and you can mitigate wear with toe and pressure changes.
Do keep in mind the repeatability of the machines and human are 0.1° typically. We see it all the time on non-adjustable suspensions.
Not apples to apples but the 350 calls for:
35 front / 38 rear and at those pressures the front eats the edges and the rear blows the center out.
So its running 40 PSI front and 34 PSI rear to hopefully get even wear across the whole tire.
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