mx5-kiwi

Hi Guys

I have a race meeting next weekend with a new set of 15x9 6ULS and a new set of 225x45 NT01's from a set of 205x50x15 on 7" wheels.

I have been using the alignment recommendations from Emilios site and am generally pretty happy with them. Using ride height and fr - Rr damper settings to get the car balanced to my liking.

My first question is,

Is the same alignment applicable for a wider tyre or do you make slight changes to compensate.....?

bit of a newbie question but alignment at this track is critical due to the couple of long drawn out RH sweepers (slow in fast out) chewing out the right rear tyre if you don't get it right.....

Second question, Does this next part sound feasible...?

"Apparently" the experienced guys add up to 1/2 deg of negative camber to the right rear (outside tyre) in tuning for this circuit to help prevent the shoulder and outside 1/3 of the tyre wearing more than the rest.

I certainly have had this unusual wear from my time there....

Savington

iTrader: (31)

If you are making adjustments to your alignment that aren't based on data from a tire pyrometer taken from your car on the tires you race on, you're just pissing in the wind.

triple88a

iTrader: (2)

Perhaps different caster?

mx5-kiwi

Thanks for the advice...I appreciate it and leads to a couple more questions...

You can't make adjustments from extreme wear in one position of the tyre i.e the sweepers I mentioned?

- 3 races in a day were enough to nearly kill that tyre in that one surface area....the rest were in normal (good) shape...bad enough that I managed to secure a waranty on the tyre as being possibly faulty. Only for the shop to be told after the fact by the area "motorsport" rep that it is a very common wear pattern for that track...(fortunately they got the credit anyway).

Whilst an infrared is not ideal, it can't give an idea of whats happening?

and further to that question...

You and Emilio both frequently tout the benefits of pyrometers (and I don't disagree with you) can either of you not source one to list on your sites?

- EVERYONE needs one (in this sub forum at least) and few of us have access to them (particularly us from smaller/ foreign countries....) price is not too much of a factor, within reason. We get gouged for many things in our market, these are a great example....

Savington

iTrader: (31)

You can, but you're not going to get the most out of the car until you collect good data from a probe-style pyrometer.

Pro teams (Audi LMP, etc) use laser pyros all the time. The difference is that they're attached to the car and they take temps in real-time and feed them back to a datalogger. The surface of the tire doesn't really matter, as the air temp affects it significantly before you can take your data. Even with a probe-type taking the temp 3/16" down into the compound, you still need to take the temps within 2-3 minutes of finishing your last hotlap to get ideal data. I will typically start with the LF tire, then do LR, RR, RF, and then do the LF again and compare the data I get. Often times the temps change 3-5* just in the time it takes me to get around the car and collect all the data, and I compensate the data I take based on that delta.

I'll add one to my site at some point, but stuff like that is hard for me to make a worthwhile margin on. I use this one: AccuTech 50640

joyrider

iTrader: (8)

Listen to this guy ....

If on a budget, JOES Racing Deluxe Racing Pyrometer is really good too.

Next time you go for alignment, I suggest you try to play with what you have in adjustability and mark it down for easy setup when you'll be at the track...

mx5-kiwi

Thanks guys, stuff to ponder for sure...

Learning how to do basic wheel alignments at the track might be a good start.

In the meantime can someone buy 3 of these and make up a plan for a live feed tyre temp gauge....

Turnigy Laser Guided Infrared Thermometer

that_dc5_kid

I autocross my miata and my 205s are too thin I can't get the power down

SK-NZ

Flamecrusher NZ have probe pyrometers: Tyre Pyrometer with Adjustable Probe - Flamecrusher

Been looking at getting that for myself but will need to wait for budget to allow

Seefo

iTrader: (5)

Good post. I have had a discussion or two with other members on here about this same topic.

mx5-kiwi

Okay so the guys with pyrometers, do you still run a proper cooling down lap or do you race in to the pits and let the car cool down stationary...?

Rightly or wrongly I think I would be concerned with the brakes, radiator and turbo heat soaking themselves over truly accurate 100% tyre temps...

What am I missing here?

(excluding a huge budget, hardware to cope and a team around me to get it all done quick smart!! )

Edit:Thanks SK-NZ great link. Will look at that, also cheaper than I thought.....

Savington

iTrader: (31)

You can maintain enough pace to work the tires at 9 or 10/10ths without working the brakes and motor at 10/10ths.

joyrider

iTrader: (8)

Ask a friend and do it for him for the next session, adjust everything accordingly and go back on track.

You can spray them if they're too hot too and go back to complete your session and bring the car in the pit without loosing too much heat in cooldown lap as said earlier.

mx5-kiwi

I have my nephew helping out at most race meetings so thats not a problem BUT mid session...I never thought of that!

Some things are just so obvious in hindsite