39 replies to this topic

[Keith Novak]

Keith,

 

Did you try a little toe in on the rear to settle the car down under braking?

I have.  Over the last couple years I've been trying various combinations of toe to see what they do.  Some work better and some are terrible.

 

Some of it also comes down to the car and the driving style.  From what I've heard about the handling of the 99 compared to the NA or particularly the 1.6, the same changes most likely will not have the exact same effect.  Similarly, I've been told that I seem to turn in pretty abruptly compared to others.  Someone with a smoother corner entry is probably going to find that what works for me isn't going to do the same for them.  I keep trying new things and I'm still developing as a driver so I'm sure I'll keep finding more tweaks that work better and worse than the last ones as I try to close the last second on the leaders.

[Mark]

Checked with my Hunter tech: He says all toe measurements are based on a 28.5" reference wheel diameter regardless of car. He also added that internally the system uses degrees for its calculations and translates to the inch or mm units for display purposes. In this case the toe plate measurements will be slightly less than the Hunter system. This info is for a 2012 Hunter Hawkeye Elite system if it matters. 

 

I believe you. But the guy who had the machine sells them for a living and I'm going by what he said. But it's very possible he misunderstood the question I asked him.
Not sure what type of machine is used at TFB(local shop)but I'm pretty confident Tim has told me the measurement it uses is 15". He always comments toe plate measurement will be larger than his machine numbers by a little.

 

[Charlie Hayes]

We use a Jim Beam @ TFB and it measures at the wheel. When using 32in toe plates the total toe is doubled in our case.

[Tom Sager]

We use a Jim Beam @ TFB and it measures at the wheel. When using 32in toe plates the total toe is doubled in our case.

 

 

I like a little Jim Beam every once in a while.  

 

[Bench Racer]

This is a acronym, what's the "J" for ??

You may have said it before but I forgot.

J~

Judgment, at least you were only off by one word, Drago was off by all four words.

[Johnny D]

Judgment, at least you were only off by one word, Drago was off by all four words.

 

Ok, I added it, so we can understand you.

http://mazdaracers.c...l=+greek +bread

 

Now don't be going hip, trendy and new on us and start using "O".

J~

[Bench Racer]

Ok, I added it, so we can understand you.

http://mazdaracers.c...l=+greek +bread

 

Now don't be going hip, trendy and new on us and start using "O".

J~

Naw, changed from "O" to "J" because many people say O is like A, everyone has one.

[Ron Alan]

Judgment, at least you were only off by one word, Drago was off by all four words.

I dont think it was on purpose...

[Bench Racer]

I dont think it was on purpose...

Really  

[svvs]

I like a little Jim Beam every once in a while.  

 

 

I must have lived here in NYC for too long.....I look at this picture and think two of the three need to be checked for adam's apples or an extra toe.

[bmw251]

Thanks for the help...... Making changes now and experimenting .

Greg

[Johnny D]

So, correct me please.

In the shop you put your toe, corner weight etc.

Test day, adjusting the toe is the roughest adjustment and possible the 1st adjustment you'd make and doesn't affects cross weight??

Spring perches would be a finer adjustment and affect cross weight?? Use the setup guide in the downloads ^^^

Sway bar, not much, leave it, full soft, or that's driving style vs mechanical grip??

Then tire pressures or those should be equal??

Am I leaving anything out?

J~

[Johnny D]

And ride height

J~

[Johnny D]

What?????

This wouldn't be closer racing ???? 

Shhh don't tell nobody.

J~

[FTodaro]

So, correct me please.
In the shop you put your toe, corner weight etc.
Test day, adjusting the toe is the roughest adjustment and possible the 1st adjustment you'd make and doesn't affects cross weight??
Spring perches would be a finer adjustment and affect cross weight?? Use the setup guide in the downloads ^^^
Sway bar, not much, leave it, full soft, or that's driving style vs mechanical grip??
Then tire pressures or those should be equal??
Am I leaving anything out?
J~

I set the toe, and the only adjustment I make to it , is to bring it back to base line, if I knock it out. Tire pressures is the finest adjustment, you can put more or less grip in the care and change cross with it.

[Keith Novak]

I set the toe, and the only adjustment I make to it , is to bring it back to base line, if I knock it out. Tire pressures is the finest adjustment, you can put more or less grip in the care and change cross with it.

I thought he was just being a smart a$$

[AW33COM]

I must have lived here in NYC for too long.....I look at this picture and think two of the three need to be checked for adam's apples or an extra toe.

 

 

You're not alone.  Something is hidden in this picture.

[Bad Rusty]

Good news, there are plenty of places at laguna SECA to adjust toe "on track". It's like a cockpit adjuster. And the two on the right also go by "Dan" and "Jerry", I've seen then in San Fran too...

[SaulSpeedwell]

Obscure but factual point:  For cambered tires, zero toe is never the least drag.  Cambered tires produce a lateral force when rolling straight, and that force is "driven" by the engine.  (Just like the torque to overcome tire stagger and differential clutch "slip" and every other drag force is "subtracted from" the torque provided by the engine).

 

For negative camber, we KNOW that some amount of toe-out is the theoretical least drag.  But, we don't have tire data, and unless someone wants to nerd out with load cells on the tie-rods, we don't know what the right number is.  I tried calculating it from the decades-old Goodyear slick data in the Milliken Racecar Vehicle Dynamics book, and came up with 3/8" (LOL???).  I actually tried that (on RA-1s), and it was definitely slower. In defense of what was likely a bogus calculation, I would expect the RA-1 and its squishy "street" carcass to produce less camber thrust than a Goodyear slick, or a current Hoosier DOT.

 

Toe-out in the rear is generally spooky, so my advice is to go with the least toe-in the rear that you can still drive, and run "some toe out" in the front".

[Keith Novak]

Toe-out in the rear is generally spooky, so my advice is to go with the least toe-in the rear that you can still drive, and run "some toe out" in the front".

Eh....what you call "spooky", I call dynamically unstable.  It will want to turn under all conditions including going straight, particularly under braking.  It's a momentum car though.  You don't get your speed going straight and it sure as heck wants to turn...  It's just that when you don't want to turn, it's kind of spooky.