Auto-X with an IRS - Ford Mustang Forums : Corral.net Mustang Forum
 
LinkBack Thread Tools Display Modes
post #1 of 24 Old 09-07-2005, 01:50 PM Thread Starter
Registered User
 
coleman2kgt's Avatar
 
Trader Feedback: (0)
Join Date: Feb 2003
Location: Corpus Christi, TX
Posts: 391
Auto-X with an IRS

I will soon be running my 00 GT with an 01 IRS at the local SCCA gatherings, and I was curious about the IRS. Any special needs? Any "free" tricks for improvements? Any way to get some negative camber out of it? Anything to watch for? I will also soon add some 03 springs and Bilsteins.

For those of you running the IRS in Auto-X, what are your impressions?

Thanks in advance!


2000 GT Current Auto-X mule/Daily Driver


Quote: "5.0Torx"

Cheap
Fast
Reliable

Pick 2...
coleman2kgt is offline  
Sponsored Links
Advertisement
 
post #2 of 24 Old 09-07-2005, 04:16 PM
Registered User
 
Trader Feedback: (33)
Join Date: Nov 2003
Location: Abingdon, Md.
Posts: 2,877
I put an 03 IRS in my 97 Cobra and love it. I don't auto-x it but I open track it. Here is what I have done with it. MM urethane IRS bushings and a-arm bushings (upper and lower), Aluminum front diff bushings, delrin rear diff bushing, MJ's/Billet Flow's diff brace, 4.30 gears, bilsteins with MM coil overs at all 4 corners, 03 Cobra drive shaft. There isn't enough adjustment to get the amount of negative camber I would like for the track. I am thinking about custom a-arms with rod ends for that reason. I still want to ugrade to DSS level 5 half shafts.

As it is it works real well. By all means do the bushing while you have ithe IRS out already. They are a major pain in the butt to install.

PGreenSVT is offline  
post #3 of 24 Old 09-07-2005, 05:07 PM Thread Starter
Registered User
 
coleman2kgt's Avatar
 
Trader Feedback: (0)
Join Date: Feb 2003
Location: Corpus Christi, TX
Posts: 391
Did the bushings provide a noticeble difference? I've read posts comparing the improvements to adding a panhard bar to a live axle.

When lowering, any thing to watch out for?

2000 GT Current Auto-X mule/Daily Driver


Quote: "5.0Torx"

Cheap
Fast
Reliable

Pick 2...
coleman2kgt is offline  
Sponsored Links
Advertisement
 
post #4 of 24 Old 09-09-2005, 12:36 PM Thread Starter
Registered User
 
coleman2kgt's Avatar
 
Trader Feedback: (0)
Join Date: Feb 2003
Location: Corpus Christi, TX
Posts: 391
ttt

2000 GT Current Auto-X mule/Daily Driver


Quote: "5.0Torx"

Cheap
Fast
Reliable

Pick 2...
coleman2kgt is offline  
post #5 of 24 Old 09-10-2005, 01:25 PM
Registered User
 
Trader Feedback: (33)
Join Date: Nov 2003
Location: Abingdon, Md.
Posts: 2,877
I did all of my mods to the IRS before I installed it so I can't compare it to the stock IRS setup. I can tell you that mine corners really flat and on the road it rides better than it did with the stick rear.
PGreenSVT is offline  
post #6 of 24 Old 09-11-2005, 12:52 PM
Registered User
 
serpentnoir's Avatar
 
Trader Feedback: (15)
Join Date: Nov 2001
Location: Detroit, MI
Posts: 1,264
Quote:
Originally Posted by coleman2kgt
Any way to get some negative camber out of it? Anything to watch for?
With the stock arms you can dial-in about 1.5degrees of negative camber. It varies from car to car. I would recommend negative camber even if you don't open track or autocross the car. You tires will thank you. The factory settings do a number on the outside edges of the rear tires.

particularly non-stock 99 Cobra w/brand C motor...
serpentnoir is offline  
post #7 of 24 Old 09-12-2005, 11:09 AM Thread Starter
Registered User
 
coleman2kgt's Avatar
 
Trader Feedback: (0)
Join Date: Feb 2003
Location: Corpus Christi, TX
Posts: 391
Thanks for all the great advice! What else? What about running sticky tires, any breakage issues?

2000 GT Current Auto-X mule/Daily Driver


Quote: "5.0Torx"

Cheap
Fast
Reliable

Pick 2...
coleman2kgt is offline  
post #8 of 24 Old 09-12-2005, 12:59 PM
Registered User
 
Trader Feedback: (33)
Join Date: Nov 2003
Location: Abingdon, Md.
Posts: 2,877
I have been unable to get anything near 1 degree negative with the stock a-arms. In fact it only gives me slightly less than .5 degrees. I'd love to be able to dial in -1.5.
PGreenSVT is offline  
post #9 of 24 Old 09-13-2005, 11:40 AM Thread Starter
Registered User
 
coleman2kgt's Avatar
 
Trader Feedback: (0)
Join Date: Feb 2003
Location: Corpus Christi, TX
Posts: 391
ttt

2000 GT Current Auto-X mule/Daily Driver


Quote: "5.0Torx"

Cheap
Fast
Reliable

Pick 2...
coleman2kgt is offline  
post #10 of 24 Old 09-13-2005, 12:01 PM
Registered User
 
Trader Feedback: (33)
Join Date: Nov 2003
Location: Abingdon, Md.
Posts: 2,877
I haven't heard of any breakage issues in road racing or auto-x, only hard drag launches. If you want to be extra safe DSS level 2 half shafts should be plenty strong for all but serious drag racing.

PGreenSVT is offline  
post #11 of 24 Old 09-14-2005, 09:11 AM Thread Starter
Registered User
 
coleman2kgt's Avatar
 
Trader Feedback: (0)
Join Date: Feb 2003
Location: Corpus Christi, TX
Posts: 391
Do you have a web address for DSS? Thanks for the info!!!!

2000 GT Current Auto-X mule/Daily Driver


Quote: "5.0Torx"

Cheap
Fast
Reliable

Pick 2...
coleman2kgt is offline  
post #12 of 24 Old 09-14-2005, 11:00 AM
Registered User
 
Trader Feedback: (33)
Join Date: Nov 2003
Location: Abingdon, Md.
Posts: 2,877
DSS is The Drive Shaft Shop. They make 2 different setups for our IRS. The level 5 stuff is indestructible. There are folks doing full drag launches on slicks with 700hp+ cars and I haven't heard of any breaking. The level 2's are plenty for a road racer though.

http://www.driveshaftshop.com/MUSTANGC.V..ivnu
PGreenSVT is offline  
post #13 of 24 Old 09-14-2005, 11:42 AM Thread Starter
Registered User
 
coleman2kgt's Avatar
 
Trader Feedback: (0)
Join Date: Feb 2003
Location: Corpus Christi, TX
Posts: 391
Well, sad to say, I have a stock SOHC for the time being. But that will change with time. Thanks for the link. So the shafts are the weak link in the IRS? I remember reading something about the knuckles breaking. Don't remember the senarios.

2000 GT Current Auto-X mule/Daily Driver


Quote: "5.0Torx"

Cheap
Fast
Reliable

Pick 2...
coleman2kgt is offline  
post #14 of 24 Old 09-14-2005, 11:54 AM
Registered User
 
Trader Feedback: (33)
Join Date: Nov 2003
Location: Abingdon, Md.
Posts: 2,877
The shafts are the first weak link then the outer cv's. The level 2's address the shafts and the level 5's include redesigned beefier outer cv's. The Level 5's are just awesome but probably not necessary for road racing. I still run the stock shafts in my 03 IRS. Everything else has been redone. If I break the stockers then I'll upgrade them. To date I've never had my Cobra on the drag strip, a road course is much more fun.
PGreenSVT is offline  
post #15 of 24 Old 09-14-2005, 01:45 PM
Registered User
 
serpentnoir's Avatar
 
Trader Feedback: (15)
Join Date: Nov 2001
Location: Detroit, MI
Posts: 1,264
Quote:
Originally Posted by PGreenSVT
To date I've never had my Cobra on the drag strip, a road course is much more fun.
isn't that the truth!

particularly non-stock 99 Cobra w/brand C motor...
serpentnoir is offline  
post #16 of 24 Old 09-14-2005, 02:22 PM Thread Starter
Registered User
 
coleman2kgt's Avatar
 
Trader Feedback: (0)
Join Date: Feb 2003
Location: Corpus Christi, TX
Posts: 391
Nothing better than nailing an apex!

Slightly off subject, but any of you guys had any luck dialing out the vibrations if the typical mustang IRS?

2000 GT Current Auto-X mule/Daily Driver


Quote: "5.0Torx"

Cheap
Fast
Reliable

Pick 2...
coleman2kgt is offline  
post #17 of 24 Old 09-14-2005, 03:29 PM
Registered User
 
Trader Feedback: (33)
Join Date: Nov 2003
Location: Abingdon, Md.
Posts: 2,877
Veeerrrryyy careful alignment of the driveshaft and pinion angle plus clocking the driveshaft. That should get you almost vibration free. A carbon fiber driveshaft will take the last little bit out. I tried a heavier driveshaft and it made things worse. You really have to play with it and can't rely on factory specs. especially if you change gears like I did. Going with 4.30's you just forget the dogbone.
PGreenSVT is offline  
post #18 of 24 Old 09-15-2005, 05:20 PM Thread Starter
Registered User
 
coleman2kgt's Avatar
 
Trader Feedback: (0)
Join Date: Feb 2003
Location: Corpus Christi, TX
Posts: 391
Anyone using the tubular KB parts?

2000 GT Current Auto-X mule/Daily Driver


Quote: "5.0Torx"

Cheap
Fast
Reliable

Pick 2...
coleman2kgt is offline  
post #19 of 24 Old 09-20-2005, 11:46 AM Thread Starter
Registered User
 
coleman2kgt's Avatar
 
Trader Feedback: (0)
Join Date: Feb 2003
Location: Corpus Christi, TX
Posts: 391
ttt

2000 GT Current Auto-X mule/Daily Driver


Quote: "5.0Torx"

Cheap
Fast
Reliable

Pick 2...
coleman2kgt is offline  
post #20 of 24 Old 09-20-2005, 03:16 PM
Registered User
 
Trader Feedback: (33)
Join Date: Nov 2003
Location: Abingdon, Md.
Posts: 2,877
I'd be interested to know that as well or anybody running the KB modified subframe.
PGreenSVT is offline  
post #21 of 24 Old 09-27-2005, 12:20 PM Thread Starter
Registered User
 
coleman2kgt's Avatar
 
Trader Feedback: (0)
Join Date: Feb 2003
Location: Corpus Christi, TX
Posts: 391
No one using the KB parts???

2000 GT Current Auto-X mule/Daily Driver


Quote: "5.0Torx"

Cheap
Fast
Reliable

Pick 2...
coleman2kgt is offline  
post #22 of 24 Old 10-01-2005, 11:24 PM
Registered User
 
Trader Feedback: (3)
Join Date: Jul 2004
Location: palmdale,california
Posts: 376
my 04 cobra i could only get .7 on the drivers side ... i told the alignment guy to grind down the eccentric bolt and the oval hole in the upper control arm if nessesary ... now i have 1.1 degrees neg camber in the rear
racebronco2 is offline  
post #23 of 24 Old 10-05-2005, 01:23 PM
Registered User
 
Trader Feedback: (0)
Join Date: Jun 2003
Location: Omaha, Nebraska
Posts: 41
http://corner-carvers.com/forums/showthread.php?t=24358

check that thread, with any abuse, you will be replacing the upper and lower control arm bushings.
89gtstalker is offline  
post #24 of 24 Old 10-05-2005, 02:16 PM Thread Starter
Registered User
 
coleman2kgt's Avatar
 
Trader Feedback: (0)
Join Date: Feb 2003
Location: Corpus Christi, TX
Posts: 391
Great thread! Thanks for the link!

2000 GT Current Auto-X mule/Daily Driver


Quote: "5.0Torx"

Cheap
Fast
Reliable

Pick 2...
coleman2kgt is offline  
Sponsored Links
Advertisement
 
Reply

Bookmarks

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Ford Mustang Forums : Corral.net Mustang Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome