Notices
Race Prep Miata race-only chat.
Sponsored by:
Sponsored by: 949 Racing

Tire Wear (More inside or outside?)

Thread Tools
 
Search this Thread
 
Old May 20, 2011 | 10:02 AM
  #21  
sixace's Avatar
Junior Member
 
Joined: Jan 2008
Posts: 227
Total Cats: 1
From: Gainesville, Tx
Default

Originally Posted by spitefulcheerio
I still don't understand what more rear camber is bad...my alignment setup is for autox. I spoke to a couple of auotx vets and they said my setup was a good streetable autox alignment
Ok, I guess "streetable" may have something to do with it, but I dunno, even then, sounds kinda bogus. You may want to verify the ax vets experience..

A proper ax setup is along the lines of -2.9 fr, -2.5 (or more) rr, max caster, bit of toe-out in front and a bit of toe-in for the rear. Track setup has already been posted.

I'm far from an expert, but just a bit of research reveals that the above ax setup is used by nationally compettive ax'ers. It could be dependant on tires/sways/springs/driving style, etc. but there it is...

I used to use the above ax setup before the track addiction hit. Now I just keep the track setup and it's ok for ax (unless your serious). Ax setup for track, not so good..

ymmv
Old May 20, 2011 | 10:05 AM
  #22  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

But m.net said I should use the Icehawk alignment!
Old May 20, 2011 | 11:21 AM
  #23  
MartinezA92's Avatar
Elite Member
iTrader: (4)
 
Joined: Aug 2009
Posts: 1,784
Total Cats: 42
From: Redwood City, CA
Default

M.net says FFS is much more betterer too, im selling my turbo ****.
Mt.net people dont know anything.
Old May 20, 2011 | 11:36 AM
  #24  
wayne_curr's Avatar
Elite Member
iTrader: (8)
 
Joined: Aug 2007
Posts: 2,712
Total Cats: 5
From: Bellingham, Wa
Default

Originally Posted by spitefulcheerio
I still don't understand what more rear camber is bad...my alignment setup is for autox. I spoke to a couple of auotx vets and they said my setup was a good streetable autox alignment
I hope I explain this right. Someone call me out if i'm not.

The way I understand it is that in a corner, your car rolls and gains more camber. Due to your front roll couple, the front of your car gains less camber than the rear so you need more static camber up front.

It seems logical to most that more camber in the rear makes sense on a RWD car but try not to believe the hype and mis-information on m.net.

Here is a good place to read about alignment specs.
http://949racing.com/miata-race-alignment-info.aspx
Old May 20, 2011 | 11:39 AM
  #25  
Gotpsi?'s Avatar
Senior Member
iTrader: (5)
 
Joined: Jan 2008
Posts: 1,260
Total Cats: 5
From: Central, TX / Bay area, CA
Default

I use the 949 alinement specs and honestly get a little more wear on the out side of the tire, I just depends on your driving style. Ive tried to get tire temps but it's rained at all the MC events I made it to this year and I blew up my car the first run last event so no such luck this year. I don't know why you would ever run more camber in the rear, Maybe drifting? The front always sees more load, thats why you run more in the front. Also Toe out makes a car twitchy, I run toe in for street cars and toe out for the track for best turn in. Sixace must be doing something right here Mad props on the 2010 Unlimited class champ.
Old May 20, 2011 | 11:40 AM
  #26  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

It is good practice to use an IF temperature gauge and actually determine what alignment works best for you. It's also why you see smart racers mark tires with chalk.
Old May 20, 2011 | 03:21 PM
  #27  
jacob300zx's Avatar
Elite Member
 
Joined: Jul 2007
Posts: 3,211
Total Cats: 151
From: Houston, TX
Default

Its the toe wearing the inside of the tire not the camber. Toe is a tire killer, common misconception is the camber doing it due to people lowering the car and not realigning the toe. Run crazy camber and no toe and profit. Fancy pants had 2.7 front and 3.0 rear, it was maxed out.
Old May 20, 2011 | 05:29 PM
  #28  
bbundy's Avatar
Elite Member
 
Joined: Jul 2005
Posts: 2,502
Total Cats: 146
From: Anacortes, WA
Default

Originally Posted by spitefulcheerio
I still don't understand what more rear camber is bad...my alignment setup is for autox. I spoke to a couple of auotx vets and they said my setup was a good streetable autox alignment
You made the mistake of listening to Miata.net which where a few loud mouth keep repeating the same wrong information until almost everyone thought it must be true.

Two reasons why it is wrong.

1) The rear suspension geometry gains more negative camber than the front as the car rolls or sqats in acceleration.

2) Front tires job is only cornering and the rear is also needed strait line acceleration.

Also for comparison BMW E30’s have very near the handling balance of a miata. factory specs also have the front tires standing straight up and a fair amount of negative camber. Anybody who has really made an E30 fast has a **** ton of front negative camber and just a bit more than stock in the rear. Similar thing works for the Miata as well.

My own experimentation has led me to the same conclusion as Emillio’s 949 alignment the guy knows what he is talking about. Much more than about -2.5 in the rear saw diminishing returns but it just got faster as I maxed out front camber to about 2.8 which is all I could get.

Autocrossing I still wear the outside edges of the tires if your driving on the street and not cornering hard a lot Toe is what kills the inside edges way more than camber.

My suggestion is Max out front camber first. Back off only enough to get the same castor on both sides what ever max you can get both sides equal with camber as the priority. Put a little less camber in the rear.

To save tire wear set the toe to 0 degrees all around. Mark the flats on your front tie rods. It helps a little if prior to an autocross you adjust the tie rods out 2 hex flats per side on the front works good. Keep it marked and you can adjust your toe yourself for different events and set it back to zero for daily use to save tires.

Bob
Old May 20, 2011 | 05:41 PM
  #29  
spitefulcheerio's Avatar
Junior Member
 
Joined: Mar 2011
Posts: 277
Total Cats: 3
From: Tallahassee, FL
Default

Thank you for that in depth description. I understand where I went wrong now.

MY only problem is at stock ride height, I'm maxed out with front negative camber. I won't be stock ride height for long and I know lowering the car adds negative camber so once I have my tokicos installed, I'll be looking to setup my alignment properly.

I'll also do that toe trick for my next autox! Thanks again
Old May 20, 2011 | 10:11 PM
  #30  
sixace's Avatar
Junior Member
 
Joined: Jan 2008
Posts: 227
Total Cats: 1
From: Gainesville, Tx
Default

Originally Posted by Gotpsi?
.... Sixace must be doing something right here Mad props on the 2010 Unlimited class champ.
Umm, thanks. But I actually don't have a clue about anything regarding mechanical or driving, except one time during an ax novice walk through, I remembered one thing the instructor said.."the three most important things in racing are":

1. Tires
2. Tires
3. Tires

In retrospect, there is one thing more important. Benjamins.
Old May 21, 2011 | 12:29 PM
  #31  
Gotpsi?'s Avatar
Senior Member
iTrader: (5)
 
Joined: Jan 2008
Posts: 1,260
Total Cats: 5
From: Central, TX / Bay area, CA
Default

Haha what tires do you run? NT01?
Old May 21, 2011 | 01:26 PM
  #32  
Savington's Avatar
Former Vendor
iTrader: (31)
 
Joined: Nov 2006
Posts: 15,442
Total Cats: 2,106
From: Sunnyvale, CA
Default

Originally Posted by Gotpsi?
I use the 949 alinement specs and honestly get a little more wear on the out side of the tire, I just depends on your driving style.
+1. Emilio's specs are a good starting point but I run more camber than that on both of our cars. My standard track **** alignment is -3.0F, -2.8R, +3.5 caster, no toe. Big power cars (250+whp) get 1/8" rear toe in.

The way to set alignment is with a tire pyrometer - plain and simple.
Old May 21, 2011 | 02:02 PM
  #33  
curly's Avatar
Cpt. Slow
iTrader: (25)
 
Joined: Oct 2005
Posts: 15,192
Total Cats: 1,398
From: Oregon City, OR
Default

Originally Posted by Savington
+1. Emilio's specs are a good starting point but I run more camber than that on both of our cars. My standard track **** alignment is -3.0F, -2.8R, +3.5 caster, no toe. Big power cars (250+whp) get 1/8" rear toe in.
Your black car doesn't have 250+whp?
Old May 21, 2011 | 08:51 PM
  #34  
sixace's Avatar
Junior Member
 
Joined: Jan 2008
Posts: 227
Total Cats: 1
From: Gainesville, Tx
Default

Originally Posted by Gotpsi?
Haha what tires do you run? NT01?
Been running R6, last event ran A6. Retarded grip, no warm up required. Cheater tires.
Old May 21, 2011 | 10:22 PM
  #35  
Pitlab77's Avatar
Elite Member
iTrader: (3)
 
Joined: Dec 2004
Posts: 2,914
Total Cats: 5
From: Houston
Default

Originally Posted by jacob300zx
Its the toe wearing the inside of the tire not the camber. Toe is a tire killer, common misconception is the camber doing it due to people lowering the car and not realigning the toe. Run crazy camber and no toe and profit. Fancy pants had 2.7 front and 3.0 rear, it was maxed out.
So true. I learned that about a year ago. I run the same agreesive camber I did before but zero to no toe. I'm seeing so much less unintentional tire wear.
Old May 22, 2011 | 05:24 PM
  #36  
jacob300zx's Avatar
Elite Member
 
Joined: Jul 2007
Posts: 3,211
Total Cats: 151
From: Houston, TX
Default

Originally Posted by Savington
+1.The way to set alignment is with a tire pyrometer - plain and simple.


spot on, if your on a budget or lazy just max it out what you can get and run zero toe.
Old May 27, 2011 | 10:30 PM
  #37  
emilio700's Avatar
Supporting Vendor
iTrader: (3)
 
Joined: May 2005
Posts: 7,626
Total Cats: 2,618
Default

Originally Posted by savington
the way to set alignment is with a tire pyrometer - plain and simple.
+1
__________________


www.facebook.com/SuperMiata

949RACING.COM Home of the 6UL wheel

.33 SNR
Old May 27, 2011 | 10:35 PM
  #38  
emilio700's Avatar
Supporting Vendor
iTrader: (3)
 
Joined: May 2005
Posts: 7,626
Total Cats: 2,618
Default

Originally Posted by bbundy
Much more than about -2.5 in the rear saw diminishing returns but it just got faster as I maxed out front camber to about 2.8 which is all I could get.
NB front subframe. We put one on every NA we race that is allowed to under whatever racing regs there are. In your case, no reason not to. You will have to source and NB rack. NB spindles also have there bosses a tiny bit lower so a tad less bump steer. If your rack is shimmed as I'm guessing it is then, just do the subframe and bumpsteer it a again to get back to where you were.

We usually pick up about .5° without changing ride height.
__________________


www.facebook.com/SuperMiata

949RACING.COM Home of the 6UL wheel

.33 SNR
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
bigmackloud
Miata parts for sale/trade
19
Jan 8, 2021 11:24 AM
Zaphod
MEGAsquirt
47
Oct 26, 2018 11:00 PM
nbdooey
Miata parts for sale/trade
9
Aug 30, 2017 09:50 PM
emilio700
Wheels and Tires
151
Jun 2, 2017 02:36 PM
Frank_and_Beans
Supercharger Discussion
13
Sep 12, 2016 08:17 PM




All times are GMT -4. The time now is 04:56 AM.