I just changed the rear alignment before the last track day.

Before I had -1.5Camber in the rear and 1/16 total toe in...at that I had outside tire wear and outer tire temps about 15-20 degrees warmer than inside.

I maxed out the camber at -2.6 deg....1/16 total toe in....now my inside tems are about 10-15 degrees warmer than the outside. I am using Falken Azenis. I have been told that 10-15 deg warmer inside on the rear is Good........

Do I need to go back to about -2.2degrees camber ???? Or is that temp differential OK

Comments

 

Why seat in for alignment - I am sure you are not that heavy .

Corner weight balance you do but 70kg will not change the camber or toe angle will it?

 

It does change it a bit. I found that if I had an instructor in the car I was better without being in the car...as the two people balanced out the difference.

 

Well that sucks because I have a lifetime alignment with them so now I have to go somewhere else and pay for it. Well thanks for the imput. Ill look around

 

for racing every thing count so driver sitting inside while doing alignment.
I've seen some of them making 0.2 camber differene (depend on your suspension), and you know once the camber change the toe change too, but if it's only for track event then is ok to skip this step.

 

Sounds good in theory but I read a lot of Japanese analysis and they said "nice" when the outside temp is slightly higher???

Looking at tyre wear, depends on track, I would say. Even tyre temp, I think is the way to go.

Is your falken softer on the outside rather than inside... the temp depends on tyre too!

 

shoot the temp on three spot, inside, middle and outside.
inside temp higher = less camber
middle temp higher = on the right spot
outside temp higher = more camber

 

Middle temp high means to much air. In a perfect world they would all be the same if your alignment and air are right.

 

since when the world is perfect.
JK

 

I plan on reducing the camber by -.4 to -2.2.

I think that will even out the tire temps. The change from -1.5 to -2.6 changed from outside temp bias to inside temp bias...need to pick a happy medium I guess.

 

Just found out the price of some thermometer with probe... AUD$99.... reasonable. I must ask some track friends to share the price

 

I use one of those before, you have to hold the needle for a 6-7 second to get a good reading, not good beacuse it takes too long for the first tire while the others cool down. the best time is do a good clean lap, then come into the hot pit and measure, and it is better getting the infrared laser thermometer fast and easy to use.

 

(Taka writing notepad) infrared laser thermo...met...er

Thanks mate... (walking away from the computer to shop downstairs)

 

The reading on a probe type will be much more accurate than an infra red for tires. The outer surface that the IR reads cools very rapidly when you stop...while the core temp that the probe checks is much slower to cool.

IR works great for brakes and radiators, A/C..intake etc....but don't work well for tires

 

I weigh 210# and it makes a huge difference in the alignment unless you are getting a street alignment that is within a certain spec range. For the track, you should shoot for spot on numbers. For that, you need to have ballast equivalent to the drivers weight in the appropriate seat. I also get aligned with a 1/2 tank of gas (as an average).

 

Right on. IR pyrometers are no good for tires. You want to measure the core temperature.

Ideally you would be measuring the temps immediately after some steady-state cornering - any straight-line driving will cool the outsides of the tires and continue to heat the insides (Because of the camber, the inside of the tire is more highly loaded when not cornering) - and those temperatures would be even. I'm guessing though that the temps you all are taking are after coming into the pits, and you probably didn't just finish a hard corner to get there. A 10 degree rise in this case is just fine.

John

 

Thanks John...I'm going to try and get on a skidpad and test this a bit more. I remember being told that a 10-15 deg bias to the inside on the rear was OK...

 

you have to go out side drive a few laps and when you feel that you did a clean lap (no traffic and no spin out or off track) you came into the hot pit and let your friend take your tire temp inside the hot pit. not after the section is finish.
my bad, on the IR, I am wrong.

 

Only AUD$99 here in Australia - I did not know it is a great tool - thanks guys.

BTW - what is the track on your avatar Winning 8? Look fun.

 

sears point

 

I will go to the track, because I want to put these on my car.
Look cool
http://www.mazdaparts.com/ProductDet...000-1124870524

 

It is - hopefully do you "need" it on the track

 

in japan the spec rx8 race have those on their car. You could use the factory one, but it look so good on the car.

 

Good for real time aquisition though.

 

^^^^The problem with that theory is you need accurate data...or it's worse than useless