Tyres and Tuning

I don’t know how to tune really but I am trying to learn. I was trying to tune a Mazda RX7 '97 for A-class I put in the standard upgrades and made hardly any tuning adjustments other than maxing out the aero.

It seems that even after I over inflated the tyres to say 40PSI they still got to about 220 degrees after 2 laps of non-aggressive driving. And also the tyre temperature seems to have no effect on the temperature difference on the centre and the edges of the tyres. By the way, I have the race tyres with the one below maximum maximum width on front and rear if that helps.

I have read about tuning and I took notes on each aspect but I can’t seem to put any of the information I have gathered into practice. I understand that changing one part of a tune can effect various other parts.

But how am I meant to find the optimal tire temperature if even when the tyre pressure is ramped up and the car becomes terrible to drive, the telemetry is giving me very similar temperature readings to when I set the tyres to 28 or 29PSI?

Thank you.

Tire temps are at its optimum when reaching 32lbs to 33lbs (when hot) depending on tire compound, as over all a +/- 5 degrees between outer/mid/inner on tire. Tires temps will vary depending on how much camber/toe/caster you use.

Set your tires PSI back to 30 and do a warm-up lap or 2. Don’t have to try and break any records or anything. Then pull up telemetry and see what tire PSI are warm. Lets say they’re 34.7 PSI after them warm up laps. To back to tune and take 2-2.5PSI from the tires to get PSI at 32.

Then do another lap with telemetry and watch your camber going thru turns. For max grip, you don’t want to see positive camber going thru turns on outside tires. You want as close to zero as you can get.

Day your rear camber is set at 1.8. You’re watching your telemetry going thru multiple turns and you notice it’s showing .6-.8 mostly. Go to tune and drop your camber to 1.4-1.5 deg and see what your telemtry shows…repeat. The numbers and contantly moving going thru turns. So don’t try and break records doing this but don’t go 8mph either.

Once I get camber semi adjusted to where I think I want it, I THEN do a lap or 2 and watch my tire temps to make sure they are staying pretty even (within .5 deg) to make sure my camber isn’t off more than I could tell.

Note, watch setting your toe. This will have an effect on inside or outside tire temps (depends whether it’s - Or + toe) That’s another discussion for another time.

Its all about balance though. That’s I how PERSONALLY start adjusting my stuff. There are probably much better tuners out there with tips I don’t know about. After the basics I mentioned, I adjust things depending on how the car is responding (oversteer or understeer)

This is exactly where I get confused. The telemetry shows that for most of my builds, camber should be in the 1.8 range f/.8 range r however LB cars consistantly have camber over 3.0 even when the telemetry shows is should be much lower. I have been using 3.5f/3.0r lately only cuz the LB cars can get away with it but Im not sure if im missing out on performance in setting it up this way.

You’re not. This is why I only use telemetry to see when to shift.

In FM5 I started going very “technical” with my tunes and used all available telemetry data to get the “perfect” tune for a particular car/class/track combo. Then, as I kept improving my driving, I realized that it really was not helping me to use such data (and believe me, I ran a lot of tests) versus going by the feel of the car and see what worked and felt better to me. Since about midway through FM5 I have always tuned by feel, and, my tunes have been run by many for top times along with my PBs getting much better (though I still have a lot to learn). As Swerve pointed out, I now use telemetry just to shift.

PRKid
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Wait, so which cars benefit from so much camber? Everything? I was using telemetry as well and ended up with much less than that on all my builds.

For background, I use no aftermarket aero so none at all if the car didn’t come with it.

I’m only versed in the low classes, but generally it’s all cars. You can run lower camber in the -1.5 range and it feels just fine on some tracks and then on others it doesn’t want to turn.

I usually end up in the -3s after starting with no adjustments. Heavy cars seem to run ok with just about any setting. I have a few where I’ve literally done nothing more than alter ARBs.

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In addition to what W4RLOCK posted above, W0RM’s guide (sticky on top of Tuners area) as some good insights. I usually use the 32-to-34 zone, yet, mainly target them based on front-2-rear load distribution by 0.5 psi on either direction.

There are also several threads already on this specific topic, so, it might be worth doing a SEARCH on this Tuners area and/or FM5 as well.

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@OP. Tire temperatures in FM6 is NOT a great feedback for tuning adjustments.

Exactly as you have stated, no matter what you do the tire temperature will stabilize at some magical temperature. And temperature comes up unrealistically quick too.

I use temperature as indicator of tire grip and tire pressure for tire ‘rigidity’. Tire pressure seems to have NO effect on top speed but it does affect the ‘feel’ of the car.

Since there is NO tire failures (that I have experienced) in FM6, one can run extreme settings and get away with it.

I share your frustrations . . .

It’s good to know it’s not me who has noticed this I will take this into account when tuning, thank you.

Thank you to everybody else as well, I have read all your posts and I have took your advice on board so thank you.

30.0 psi = Stock (older Bias Ply)
29.0 psi = Stock (modern Radials)
28.5 psi = Street
26.5 psi = Sport
26.0 psi = Drag
25.5 psi = Race
27.5 psi = Off-Road

Where did you get this data? And are those cold or warm ?

Funny, I do it the other way around:

Stock / Street: 28
Sport: 28.5
Race: 29

On race cars Stock can be Race compound (if only Drag is offered as upgrade choice), so in this case I take 29 too.

Race temp to 30 degrees
Stock to 32 degrees
Might have to tweak some bit to get to correct temps.
Of course, it is all a preference, track, car, etc…

Never noticed any lap time change via tuning tires. You can literally run the same settings on every tire on every track including night and rain and still post top times.

With all the bragging T10 did about tires, you would think you would need something different for various types of tracks and weather.

I did notice that the temps changes a lot from different compounds. I build a car up yesterday and the tyer with the best braking is the stock compound.

Agree with you RPM, it didn’t make my LT any better, but it did feel better for handling. probably so small of a difference, it becomes a mute point.

There is very little i can add at this point, many others have given you some great advice and beaten me to the punch.
The only thing I can really say personally is that i believe there is a sweet spot between 27-33 psi, additionally when sorting camber you want to tune it for the faster corner on the track, that way you know it will grip on every other corner.

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