E46 BMW Social Directory E46 FAQ 3-Series Discussion Forums BMW Photo Gallery BMW 3-Series Technical Information E46 Fanatics - The Ultimate BMW Resource BMW Vendors General E46 Forum The Tire Rack's Tire Wheel Forum Forced Induction Forum The Off-Topic The E46 BMW Showroom For Sale, For Trade or Wanting to Buy

Welcome to the E46Fanatics forums. E46Fanatics is the premiere website for BMW 3 series owners around the world with interactive forums, a geographical enthusiast directory, photo galleries, and technical information for BMW enthusiasts.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.

Go Back   E46Fanatics > Tuning & Tech > Motorsports & Track Forum

Motorsports & Track Forum
From Auto-X to Trackday to Racing and Professional Motorsports this is the place to discuss making BMWs fast

Reply
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 12-03-2004, 03:06 PM   #1
Machan
Registered User
 
Join Date: Jan 2004
Location: Chicago North Shore
Posts: 232
My Ride: 330i and 325CiC
tire question for Auto-X

I have a 2004 325 CiC which doesn't have a sports package so it has all-season michelin tires 205/55/R16.

I want to mount a more fun tire for summer and autocross but I want to stick with 16"s to avoid taking a plus sizing penalty (my club's point scoring is a little funny).

Anyway, the natural next widest tire would be a 225/50/R16 with some summer rubber like a Kumho ECSTA MX. This should be a really easy swap and should work well with my car and I think I can be competitive with that setup even though I'm driving a convertible.

I can mount the 225/50/R16 on a 16X7" or a 16X7.5" wheel.

My question is, how much am I going to gain with the 7.5+ wide wheel versus the 7" wide wheel with the same width tire (225/50)? keep in mind that the 7.5" tires might be a little heavier.
__________________
if you are a European car fanatic and you live near Chicago check out:
http://www.euroteknik.com
Machan is offline   Reply With Quote
Ads by Google

Guests, get your FREE E46Fanatics.com membership to remove this ad.
Old 12-03-2004, 06:20 PM   #2
IDLOOK2
Registered User
 
Join Date: May 2002
Location: Chicago
Posts: 381
My Ride: 00' 328Ci
Send a message via AIM to IDLOOK2
a little more stablility in the corners, but not much. Assuming the weight difference isn't too high, the difference from 7 to 7.5 should be a positive effect.
__________________
Mark - 00' 328Ci
IDLOOK2 is offline   Reply With Quote
Old 12-03-2004, 08:22 PM   #3
notE46
Where am I?
 
Join Date: Jun 2003
Location: CA
Posts: 1,807
My Ride: M Coupe
first time autoxing? then I would say you wont be competitive even if you spend $20K on the car

but that is true for 99% of the population.

I say keep your stock tires and use them to learn the car.

I'm making some assumptions here since you are asking some basic question that you have no or very little autox/track experience.
__________________
'87 325iS Sold but not forgotten.
'08 MINI Cooper S Mellow Yellow
'00 M Coupe Dakar Duck
'02 330ia
notE46 is offline   Reply With Quote
Old 12-05-2004, 05:14 PM   #4
Machan
Registered User
 
Join Date: Jan 2004
Location: Chicago North Shore
Posts: 232
My Ride: 330i and 325CiC
I've done 4 autocrosses (3 in that car) and a car control clinic. I took a trophy (1st in my class) for the last event. That was mainly because it was pouring buckets of rain and my all-season tires helped me out and some of the best drivers didn't show. I was also using DSC which is more sophisticated on my late model E46.

I'll be doing about 12 autocrosses next year (6 with the local Audi club and 6 with BMW club). I do think I can be competitive in the BMW club.

My goal for next year is to score points in each event and try to finish 3rd in my class for the season. There is a husband/wife team with a BMW 2002 race car that is well equipped for autocross. They are both great drivers and dominate the class so that's why I'm shooting for third.

I think having some slightly wider summer tires would be necessary though.




Quote:
Originally Posted by notE46
first time autoxing? then I would say you wont be competitive even if you spend $20K on the car

but that is true for 99% of the population.

I say keep your stock tires and use them to learn the car.

I'm making some assumptions here since you are asking some basic question that you have no or very little autox/track experience.
__________________
if you are a European car fanatic and you live near Chicago check out:
http://www.euroteknik.com

Last edited by Machan; 12-05-2004 at 05:33 PM.
Machan is offline   Reply With Quote
Old 12-05-2004, 05:36 PM   #5
Machan
Registered User
 
Join Date: Jan 2004
Location: Chicago North Shore
Posts: 232
My Ride: 330i and 325CiC
another reason for wanting to switch to some summer tires is that we are using the all-season tires in the winter, which in chicago isn't too bad but you still need some decent tires. I don't want to wear out the all-season tires doing autocrosses and then having my wife slipping and sliding around in the snow because the vert is her daily driver.

plus summer tires (like a Kumho) can be chaper than my OEM michelins.
__________________
if you are a European car fanatic and you live near Chicago check out:
http://www.euroteknik.com
Machan is offline   Reply With Quote
Old 01-10-2005, 11:07 AM   #6
marsfire0
Registered User
 
Join Date: Jan 2005
Location: Los Angeles, CA
Posts: 59
My Ride: 997, s2k,e30m3, ae86
summer tires should help out a lot too just in terms of grip! sticky tires make a HUGE difference in autox!

the kumho MX's are good. you might also want to look into Falken Azeni R's. Those are very cheap and VERY VERY good for autox. i hear they arent as good for the track, but for autox, theyre awesome. they come in a variety of sizes too up to 17"
__________________
marsfire0 is offline   Reply With Quote
Old 01-10-2005, 01:11 PM   #7
Fandango Racing
Registered User
 
Join Date: Sep 2004
Location: Charleston, sc
Posts: 81
My Ride: 2 M3s 1race 1 street
I have won four Solo 2 and one Solo 1 championship, and I can't help you with tire sizes but will tell you that buying autocross tires for the car is a great idea. You might want to do a few autocross with your street tires first so you have the feeling of elation when you switch to autocross tires but most good street tires are just as expensive and many times more expensive then autocross tires. Running street tires on the street and autocross tires at the autocross is really CHEAPER in the long run because your streets will last you three times as long.
Fandango Racing is offline   Reply With Quote
Old 01-10-2005, 01:15 PM   #8
Fandango Racing
Registered User
 
Join Date: Sep 2004
Location: Charleston, sc
Posts: 81
My Ride: 2 M3s 1race 1 street
Something else to consider - In SCCA autocross a wider wheel then stock will move you out of stock classes, so plan accordingly
Fandango Racing is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not 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 On
Censor is ON





All times are GMT -5. The time now is 02:59 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
(c) 1999 - 2011 performanceIX Inc - privacy policy - terms of use