Was wondering if somebody could tell me the proper racing alignment for a 2017 Grand Sport. I run about 10 track days a year at Mid Ohio. I was talking with a gentleman that said not to use set up that is in owners Manuel.
Thnks

 

[QUOTE=Flick6468;1595257579]Was wondering if somebody could tell me the proper racing alignment for a 2017 Grand Sport. I run about 10 track days a year at Mid Ohio. I was talking with a gentleman that said not to use set up that is in owners Manuel.


Front
min max
-0.7 -0.9 7.5 8.5
-1/16" 0
-0.4 -0.6 -1/16" 0
Camber (deg) Caster (deg) Toe
Camber (deg) Toe
Notes
Rear
These settings will provide good performance and good tire wear
Front
min max
-1.1 -1.3 7.5 8.5
-1/16" 0
-0.7 -0.9 -1/8" -1/16"
Camber (deg) Caster (deg) Toe
Camber (deg) Toe
Notes
Rear
These settings will provide good all around performance. The tires will wear the inside edges in street use and the outside edges on the race track. This is a good dual purpose alignment.
Front
min max
-1.6 -1.8 7.5 8.5
-1/16" 0
-0.9 -1.1 -1/8" -1/16"
Camber (deg) Caster (deg) Toe
Camber (deg) Toe
Notes
Rear
These settings will provide great track performance. The tires will wear the inside edges
in street use, and the car may tend to grab the lanes of the road. Race tires will wear well
at the track and provide high levels of grip. This alignment is compromised towards track use.
Front
min max
-2.8 -3.0 6.5 7.5
-1/16" 0
-1.5 -1.7 -1/8" -1/16"
Camber (deg) Caster (deg) Toe
Camber (deg) Toe
Notes
Rear
These settings are a good starting point for a car with polyurethane or stock control arm bushings. This alignment requires DOT race tires to function appropriately.
This is a starting point only, testing and monitoring tire temperatures and pressures are required to optimize any setup.
Front
min max
-2.4 -2.6 6.5 7.5
-1/16" 0
-1.2 -1.4 -3/16" -1/8"
Camber (deg) Caster (deg) Toe
Camber (deg) Toe
Notes
Rear
These settings are a good starting point for a car with mono-ball or spherical control arm bushings. This alignment requires DOT race tires to function appropriately.
This is a starting point only, testing and monitoring tire temperatures and pressures are required to optimize any setup.
Front
min max
-3.0 -3.2 6.5 7.5
-1/16" 0
-2.0 -2.3 -3/16" -1/8"
Camber (deg) Caster (deg) Toe
Camber (deg) Toe
Notes
Rear
These settings are a good starting point for a car with mono-ball or spherical control arm bushings. This alignment is designed and tested with race slicks, not DOT tires.
This is a starting point only, testing and monitoring tire temperatures and pressures are required to optimize any setup.
1/12/2010

 

Let me put up a link to those specs posted above - which appear to be Pfadt specs from the link I'm posting below, but are not easy to read and understand.

Butt....First of all let me say that, although the Pfadt specs aren't too bad, however the TOE SETTINGS ARE BACKWARDS!!!!

It doesn't even say it on the spec sheet linked below, but for some stupid reason Pfadt uses a negative/minus sign to indicate toe-in, whereas EVERYBODY else uses a positive/plus sign to indicate toe-in.

Second of all, these specs were first published by Pfadt years ago, and although they aren't bad for the previous generations, THEY DON'T ADDRESS REAR CASTER AT ALL!!! So, they aren't complete for the C7, where rear caster is a VERY IMPORTANT spec, especially for the track!!

So....below is a link to the Pfadt specs in the previous post that do not have the Pfadt alert that they used on all their other alignment spec sheets.

Here's the alert Pfadt used to post on their spec sheet - and that you can see on the 2nd link just below:

Here are links to two versions of the Pfadt alignment specs:

http://www.pfadtracing.com/blog/wp-c...-alignment.pdf

http://www.pfadtracing.com/blog/wp-c...-9.12.2011.pdf


If you do use those Pfadt specs, make sure you (or any shop you take it to) understands that the negative toe spec means toe-in, which is opposite of all alignment racks and the convention everybody else uses.


For a C7 I recommend the following specs from DSC Sport. You can see that they have a recommendation for the VERY IMPORTANT REAR CASTER spec. You can read in a recent post by DSC that they after a lot of testing they are zeroing in on +0.75° as the optimal setting for rear caster - scroll down to post# 798 to read that (their spec sheet below shows +0.7°):

https://www.corvetteforum.com/forums...ations-40.html

Here's their alignment spec sheet, which I highly recommend - whether you have their mag shock controller or not. And, yes - their negative toe spec uses the standard convention for indication of toe-OUT. -0.5mm is very slight toe-out setting of less than 1/50th of an inch:

http://www.dscsport.com/downloads/se...-alignment.pdf

 

BEZ06, In the past you and others had expressed some concern about toeing out the IRS. Does this mean that you are now comfortable with the slight toe out in the rear?

After running .03 toe in for nearly 12 years on my IRS Mustang Cobra, I'm a little hesitant to try it on my Z51

 

I'm VERY comfortable with toe-out for the rear!!

DSC has the mag shock controller that many of us have bought. I have it, and really like what it does for the suspension - both for a comfortable ride on the street, and outstanding track performance!!

The toe-out DSC recommends is actually so slight that it's virtually a zero toe setting - both front and rear.

Generally for the street for a RWD car, there will be slight toe-in both front and rear.

Many of us track hounds run a little toe-out up front to get a little crisper turn-in, but it usually causes a little wandering/dartiness if you run front toe-out on the street

However, as you are concerned about toe-out in the rear - so was I when DSC first advocated it. We have always wanted toe-in for the rear to help with rear end stability when putting down the power during track-out.

But, Mike Levitas, who drives for TPC racing, and is a Rolex24 winner along with many other prestigious races in Porsches, has a C7 Z06 as his personal car.

Mike has done extensive testing with his own car, including in about March or April when he ran it at VIR and fine tuned a calibration for the DSC controller for the C7. I just ran VIR with that calibration and DSC alignment specs last month at the NCM HPDE with great results!!

During Mike's research for alignment specs and DSC controller calibrations for the C7, he analyzed the rear "toe curve" or "toe-circle" as he calls it - what we usually called bump-steer. He determined that the rear toe moves in-and-out with compression/rebound of the shocks.

Here's a post he made in response to a question:

And here's Mikes response:


When in a static, shock centered condition (zeroed when sitting still on a level surface with fuel and driver in the car), when doing an alignment set the toe to that very slight toe-out spec.

When the shock is compressed (outside shock in a turn, or both rear shocks with the rear getting loaded during acceleration), the toe moves to a toe-in position - and if set to that very slight toe-out when doing your alignment with centered shocks, the toe-in during compression will bring you to the perfect toe-in for best rear end stability when you apply power when tracking out of the corner or accelerate hard down the straight.

Of course, with the adjustable rear caster on the C7, it's very important that the caster is set properly as well. The GM rear caster spec is 0.0° +/-0.8°. Mike recommends +0.7° to +0.8°, so that's within the GM specs.

Bottom line - when the rear caster is set properly, the very slight static toe-out will go to the perfect toe-in condition when the shock compresses during a turn.

.

 

Question -

According to this: http://www.corvetteactioncenter.com/...2017-1350.html

GM says that we shouldn't remove washers from the rear upper control arms for a GS, do we remove the washers from the front upper control arms? I am getting ready to drop the car off for an alignment later this week and wanted to pull the washers prior to putting the car on the rack. I will be following the numbers that DSC put out for track/street applications. I had their controller on my previous car (911) and it transformed the handling of the car, I am a big fanboy of their stuff.

 

This is what I used for my GS this past weekend and it tracked great.

 

Thank you for the clarification on this- the fine print says not to remove any washers - front or rear.

 

Looking to track my GS next month for the first time. -2° camber is a lot to go back on the street with. Sounds great for the track but won't this wear out the inside edge on the street?

 

I ended up doing 1.8 and after a couple track days I really liked it. As i get faster I may have to increase it to 2+ but so far the wear has been pretty even. I won't really know for sure till I completely wear out the stock set of tires.

 

I did my first track day in my GS last weekend at TWS. I had Track Time Performance in Houston set my alignment to the Street/Occasional Track settings from DSC Sport seen above except they set the rear to a slight toe in instead of out. I only have experience on the street to compare it to but I thought the car was very stable. The rear end wasn't snappy at all and it was easy to catch when it broke loose. The rest of my car is stock and I was running Cup2 tires that had about 1000 miles on them.

 

I maxed out my camber. I'm at -2.8 Front and -1.8 rear. If you run more than a few track days a year, it's worth the extra camber, as you will burn through your tires tracking faster than the camber will. And the extra camber gives you better wear on track.

 

Thanks for posting the alignment sheet. Looks familiar, Pep Boys or Tires Plus maybe?

I'm probably only going to track a couple days a year. My GS is my daily driver with a break once in a while on my Harley. Don't ride the Harley much down here in the summer time as its too hot.

 

No way would I go to a tire shop for an alignment of a C7. I went to Able Chevy. Most chevy dealers seem to struggle with caster on these cars. Able is squared away as they do a lot of track cars.