Jump to content

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)

Goofy Tire size question


Recommended Posts

Hello all:

 

TL;DR: can I reprogram computer to accept different diameter front tires than rear?

 

I've got a 99 986, 5 speed manual (not sure if it will matter), and 17" twist wheels. I had thought about doing this on a car for a long time, and finally did: I got tires with a size higher aspect in rear and a size lower in front (normal is 205 50 front, I did 205 45, and in rear 255 45 instead of 40). The thought behind this was improved steering without sacrificing ride.

 

Well, this wasn't the best idea, as you probably know. The issue that started after I left the tire shop and ever since is that when I press in the clutch over 30 mph, revs hang or increase to around 3-4k. This is a failsafe because of the ABS sensors reading differently and the computer being angry with me... if I shut off the traction control, the issue vanishes. My question:

 

Can I reprogram anything to accept the differing diameter tires? Or do I just need to hang my head in shame and buy matching diameter to my rears? I REALLY like the steering feel, but the rev hanging isn't something I wanna live with. And leaving the TC on sounds like a good idea.

 

Thanks for any help and for reading this far.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.