Alignment...before/after - CorvetteForum - Chevrolet Corvette Forum Discussion

Notices
Autocrossing & Roadracing Suspension Setup for Track Corvettes, Camber/Caster Adjustments, R-Compound Tires, Race Slicks, Tips on Driving Technique, Events, Results
Sponsored by:
Sponsored by:

Alignment...before/after

Reply

 
 
 
Old 02-19-2018, 04:32 PM
  #1  
shizon'00
CF Senior Member
Thread Starter
 
shizon'00's Avatar
 
Member Since: Oct 2000
Location: Herndon VA
Posts: 2,130
Thanks: 0
Thanked 18 Times in 14 Posts
Default Alignment...before/after

I just had to share the difference between an alignment at any place and an alignment at a place that knows what they are doing.

Before (dealer attempted to set alignment after some trans warranty work):




And After (TPC Racing/DSC Sport):



I drove the 'before' alignment at VIR on labor day last year. It was twitchy and pulled right, but not bad enough that I felt it was a safety issue. I can't wait to go back in March and feel the difference after seeing those measurements.

Thanks to Tom Chan and Mike Levitas at TPC Racing. Best guys to work with!

Here's to track season!!! DILLY DILLY!
shizon'00 is offline  
Reply With Quote
The Following User Says Thank You to shizon'00 For This Useful Post:
Poor-sha (02-19-2018)
Old 02-19-2018, 04:57 PM
  #2  
thebishman
CF Senior Member
 
Member Since: Aug 2000
Location: Overland Park KS
Posts: 2,449
Thanked 287 Times in 211 Posts
Default

^ Now that’s how to do an alignment!
thebishman is offline  
Reply With Quote
Old 02-19-2018, 05:12 PM
  #3  
Z06Shark
CF Senior Member
 
Z06Shark's Avatar
 
Member Since: Dec 2016
Location: Motor City
Posts: 316
Thanked 35 Times in 29 Posts
Default

It should be night & day - mine was exactly like yours and it tracks straight!
Z06Shark is offline  
Reply With Quote
Old 02-19-2018, 08:57 PM
  #4  
Nowanker
CF Senior Member
 
Member Since: Nov 2013
Location: SF Bay Area Ca
Posts: 1,216
Thanked 99 Times in 86 Posts
Default

As a purveyor of high quality alignments, I've been on this bandwagon a long time.
The difference between the standard tire shop alignment and one from a specialty shop is night and day.
The typical alignment guy is paid on a percentage basis ('flat-rate'), making him highly motivated to crank out as many as possible in a day.
In CA anyway, all that is legally required is that work is performed to the 'minimum accepted industry standards', which means within factory tolerances. There's a wide range +/- involved... it can be in spec but still swerve off the road when you let go of the wheel. If you're not concerned about that, a LOT of time can be shaved from the job. Most cars will still drive OK. If not, very few people will actually notice anything amiss, and fewer still will bring it back and complain. If you're discerning, or want something more performance oriented, find a specialist but don't expect it for $69.95.
ALWAYS ask for a printout of the settings, and don't be afraid to ask why any readings aren't the same side-to-side. Alignments aren't magic, and if they can't get the car 'square' there's a reason. If they can't explain it in plain English, maybe they don't really understand the angles themselves...
Sorry for the rant!
Nowanker is offline  
Reply With Quote
Old 02-19-2018, 09:55 PM
  #5  
davidfarmer
CF Senior Member
Support Corvetteforum!
 
davidfarmer's Avatar
 
Member Since: Sep 1999
Location: CONCORD NC
Posts: 10,446
Thanked 60 Times in 49 Posts
Default

front toe in???
davidfarmer is offline  
Reply With Quote
Old 02-20-2018, 12:08 PM
  #6  
Nowanker
CF Senior Member
 
Member Since: Nov 2013
Location: SF Bay Area Ca
Posts: 1,216
Thanked 99 Times in 86 Posts
Default

Originally Posted by davidfarmer View Post
front toe in???
...or is that rear toe out?
Looks like a Hunter machine, typically read -toe values as toe out.
I don't know how a C7 reacts to rear toe, but I wouldn't set it there unless I had a damn good reason...
Nowanker is offline  
Reply With Quote
Old 02-20-2018, 12:34 PM
  #7  
shizon'00
CF Senior Member
Thread Starter
 
shizon'00's Avatar
 
Member Since: Oct 2000
Location: Herndon VA
Posts: 2,130
Thanks: 0
Thanked 18 Times in 14 Posts
Default

There's a big long thread in the C7Z section if you search for alignment around the research and experiences behind these numbers from Mike Levitas. It's a pretty good read if you get time and want to find it.
shizon'00 is offline  
Reply With Quote
The Following User Says Thank You to shizon'00 For This Useful Post:
Nowanker (02-20-2018)
Old 02-20-2018, 07:41 PM
  #8  
RichieRichZ06
Supporting Vendor
 
RichieRichZ06's Avatar
 
Member Since: Nov 2005
Location: Supporting the Corvette Community at Abel Chevrolet in Rio Vista, CA 707-374-6317 Ext.123
Posts: 13,653
Thanked 348 Times in 205 Posts
St. Jude Donor '08
Default

Originally Posted by Nowanker View Post
...or is that rear toe out?
Looks like a Hunter machine, typically read -toe values as toe out.
I don't know how a C7 reacts to rear toe, but I wouldn't set it there unless I had a damn good reason...
Usually toe out in the rear is not good, but the toe gain on these cars with stock suspension is a lot so it's recommended starting with a little toe out, which will cause it to toe in with any suspension travel. If the car has the solid rear toe links (Granatelli or LG) than you'll want a touch of toe in for the rear due to the toe curve changing by eliminating the cam and going with a threaded link.

The only thing I see that I don't agree with is the -1.0 rear caster notated at the top. Typically you want + rear caster in these and much closer to +.8 - +1.0.
RichieRichZ06 is offline  
Reply With Quote
Old 02-20-2018, 09:13 PM
  #9  
Nowanker
CF Senior Member
 
Member Since: Nov 2013
Location: SF Bay Area Ca
Posts: 1,216
Thanked 99 Times in 86 Posts
Default

Sounds like a damn good reason...
Nowanker is offline  
Reply With Quote
Old 02-23-2018, 10:52 PM
  #10  
Bill Dearborn
Tech Contributor
 
Bill Dearborn's Avatar
 
Member Since: Oct 1999
Location: Charlotte (formerly Endicott, NY) NC
Posts: 31,281
Thanked 2,467 Times in 1,697 Posts
Default

Originally Posted by RichieRichZ06 View Post
Usually toe out in the rear is not good, but the toe gain on these cars with stock suspension is a lot so it's recommended starting with a little toe out, which will cause it to toe in with any suspension travel. If the car has the solid rear toe links (Granatelli or LG) than you'll want a touch of toe in for the rear due to the toe curve changing by eliminating the cam and going with a threaded link.

The only thing I see that I don't agree with is the -1.0 rear caster notated at the top. Typically you want + rear caster in these and much closer to +.8 - +1.0.
Since these pictures were taken at TPC the -1 is probably a mistake in printing it on the display. TPC/DSC is the one that says it should be set at +0.7.

Bill
Bill Dearborn is offline  
Reply With Quote
Old 02-26-2018, 04:13 PM
  #11  
rabrooks
CF Senior Member
 
rabrooks's Avatar
 
Member Since: Mar 2011
Location: Bath NC
Posts: 1,388
Thanked 41 Times in 38 Posts
Default

Originally Posted by davidfarmer View Post
front toe in???
I was about to ask the same thing. It looks like the front and rear toe are in the same direction. But I'm a c6 guy. So maybe it calls for something different.

Last edited by rabrooks; 02-26-2018 at 04:16 PM.
rabrooks is offline  
Reply With Quote
Old 02-26-2018, 07:01 PM
  #12  
Poor-sha
Track Rat
Support Corvetteforum!
 
Poor-sha's Avatar
 
Member Since: Oct 2006
Posts: 4,769
Thanked 1,571 Times in 680 Posts
Default

Originally Posted by rabrooks View Post
I was about to ask the same thing. It looks like the front and rear toe are in the same direction. But I'm a c6 guy. So maybe it calls for something different.
Both are toe out. See RichieRich's comment about toe curve on the C7Z.
Poor-sha is offline  
Reply With Quote
Old 02-28-2018, 06:39 PM
  #13  
3X2
CF Senior Member
 
3X2's Avatar
 
Member Since: Jan 2000
Location: Blue Bell, PA
Posts: 1,681
Thanks: 0
Thanked 103 Times in 84 Posts
Default

Rear needs toe in not toe out.
3X2 is offline  
Reply With Quote
Old 02-28-2018, 07:36 PM
  #14  
STANG KILLA SS
CF Senior Member
 
STANG KILLA SS's Avatar
 
Member Since: Feb 2016
Location: Killeen Texas
Posts: 2,349
Thanked 109 Times in 90 Posts
Default

i sure hope you were sitting in drivers seat. it make a HUGE difference on alignment.
last 2 ive done, if i so much as moved my arm in the drivers seat it changed the camber, etc etc numbers.
new machines are incredibly accurate.
STANG KILLA SS is offline  
Reply With Quote
Old 03-01-2018, 11:28 AM
  #15  
RichieRichZ06
Supporting Vendor
 
RichieRichZ06's Avatar
 
Member Since: Nov 2005
Location: Supporting the Corvette Community at Abel Chevrolet in Rio Vista, CA 707-374-6317 Ext.123
Posts: 13,653
Thanked 348 Times in 205 Posts
St. Jude Donor '08
Default

Originally Posted by 3X2 View Post
Rear needs toe in not toe out.
Um, not true in a C7 unless you've changed to the solid rear toe links. Factory suspension will require slight static toe out in the rear due to the rear suspension geometry and toe gain curve.
RichieRichZ06 is offline  
Reply With Quote
Old 03-01-2018, 11:44 AM
  #16  
3X2
CF Senior Member
 
3X2's Avatar
 
Member Since: Jan 2000
Location: Blue Bell, PA
Posts: 1,681
Thanks: 0
Thanked 103 Times in 84 Posts
Default

Originally Posted by RichieRichZ06 View Post
Um, not true in a C7 unless you've changed to the solid rear toe links. Factory suspension will require slight static toe out in the rear due to the rear suspension geometry and toe gain curve.
Even GM's own specs, Document ID: 4042550 , which is for a stock car, call for rear toe in. I measure toe in inches not millimeters so I don't know what -0.5mm is in inches, but toe out is not what you want.

Wheel Alignment
Caution: Using these wheel alignment settings may cause excessive tire wear. Only use these wheel alignment settings for racing or competitive driving. Excessive tire wear is not covered under the vehicle warranty.
If the vehicle is equipped with the Z51 Performance Package or is a Z06, the racing and competitive driving wheel alignment settings should be set as follows:
Alignment should only be done by adjusting the lower control arm cam bolts and by removing a maximum of one washer between the upper control arms and frame.
Alignment values are targets. See your dealer for tolerances.
Front (per corner)
Caster: +7.0 degrees
Camber: -2.0 degrees
Toe: 0.05 degrees toe in
Rear (per corner)
Caster: 0 degrees
Camber: -2.0 degrees
Toe: 0.05 degrees toe in
Thrust Angle: 0 degrees
3X2 is offline  
Reply With Quote
Old 03-01-2018, 12:16 PM
  #17  
fleming23
CF Senior Member
 
fleming23's Avatar
 
Member Since: Feb 2009
Location: Dallas Georgia
Posts: 2,358
Thanked 433 Times in 304 Posts
Default

Originally Posted by 3X2 View Post
Even GM's own specs, Document ID: 4042550 , which is for a stock car, call for rear toe in. I measure toe in inches not millimeters so I don't know what -0.5mm is in inches, but toe out is not what you want.

Wheel Alignment
Caution: Using these wheel alignment settings may cause excessive tire wear. Only use these wheel alignment settings for racing or competitive driving. Excessive tire wear is not covered under the vehicle warranty.
If the vehicle is equipped with the Z51 Performance Package or is a Z06, the racing and competitive driving wheel alignment settings should be set as follows:
Alignment should only be done by adjusting the lower control arm cam bolts and by removing a maximum of one washer between the upper control arms and frame.
Alignment values are targets. See your dealer for tolerances.
Front (per corner)
Caster: +7.0 degrees
Camber: -2.0 degrees
Toe: 0.05 degrees toe in
Rear (per corner)
Caster: 0 degrees
Camber: -2.0 degrees
Toe: 0.05 degrees toe in
Thrust Angle: 0 degrees
While I do disagree with you, C7s that get tracked should start with slight toe out, you are arguing about roughly 1/16th of a difference in TOTAL toe from TPC's recommended .5mm out to your .05 degrees in. So roughly 1/32" per corner as .05 degrees of toe is roughly .02" for a 26.6" wheel. TPC mapped out the curve and as Rich mentioned, you get gain through the movement.
fleming23 is offline  
Reply With Quote
Old 03-01-2018, 12:43 PM
  #18  
C6_Racer_X
CF Senior Member
 
C6_Racer_X's Avatar
 
Member Since: Jun 2017
Location: North Georgia, USA
Posts: 1,669
Thanked 118 Times in 92 Posts
Default

Originally Posted by 3X2 View Post
Even GM's own specs, Document ID: 4042550 , which is for a stock car, call for rear toe in. I measure toe in inches not millimeters so I don't know what -0.5mm is in inches, but toe out is not what you want.
For the conversion, Google is your friend. -0.5mm is about -0.020 inches.

Toe out definitely helps the car rotate. It's a nice thing for front heavy, front wheel drive cars on the race track. I'm not sure it's what I'd want for a Corvette. There is some toe change with suspension travel (bump steer). If it toes in for compression and out for rebound, then starting with a bit of toe out wouldn't be horrible.

BTW, the Google conversion/calculator thing is quit handy for other calculations. If you want to know how many BTU's go into your brakes for a full stop from 120mph, you can ask Google that as well.
C6_Racer_X is offline  
Reply With Quote
 
 
 


Thread Tools
Search this Thread
Sponsored Ads
Vendor Directory

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: