Quick Question Thread

[ThrowMeAHotdog]

Use this thread to ask a question and get an answer

[ThrowMeAHotdog]

Say i take a car and increase the tyre width to increase grip but notice they now dont get up to race temp because of the added surface area. Will reducing the width slighty increase grip due to increased temp? I know there are other ways to increase temperature, but this is bugging me

[BiggLou55]

Reduce your tire pressure in .5 increments until you get to the range you need... The tire should be cooler on the outside compaired to the inside, but no more than 10-20 degrees.... if the center is cooler than the outside or inside, the pressure is too low, and if the center is hotter than the outside and inside, the pressure is too high....

[ThrowMeAHotdog]

Done all that, including stiffening springs, and im still not reaching peak temp even at laguna seca when i tried 15psi... Does tyre compound affect temp? If so, if i downgrade the compound will the grip effectively be the same because of the higher temperature? That way i can free up some PI points for some different upgrades

[Lowflyinmx3]

You know what, I noticed the same problem the other day. I was testing various spec car combos out and even when I stopped and did a 2 minute burnout my tires never went green. Wonder whats going on?

[BiggLou55]

I'm having issues getting rear tires on FWD cars up to temp.... still working on it though... have you tried increasing the downforce over the drive wheels?

[DougieManCan]

What I have found in real life and to some extent on FM.

RWD - Rear tyres, heat up due to the torque being put through them plus the breaking of traction either in a straight line or in a sideways motion.

RWD - Front tyres, dont heat up as quick as rears but this time will gain heat mainly due to understeer trying to tear the tyre sideways.

FWD - Front tyres, this is the same principle as the rear tyres on a FWD car but this time they heat up quicker due to the increased weight on them.

FWD - Rears tyres, only follow the fronts there is not normally too much weight on them and no torque, they rarely get any side motion due to oversteer and if they do its not for long.

RWD and AWD rear tyres should always come up to temp quick even on the first lap the front will follow but a little slower. If you give us an example of car and track we might be able to replicate it and come up with a setup

Things like track temperature, aero effect, temperatures, weight bias, compound and ackerman steering angles all effect the temperatures of a tyre. One thing I wouldnt suggest is reducing (or increasing) the pressure too much as you will effectivly reduce grip and so slow your car down in the corners and in turn reduce the forces on the tyres and finally (when i get to my point) reduce the heat in the tyres.

bit long but i hope some of it helps

[ThrowMeAHotdog]

What class cars are we talking about? Im tuning a class B car, maybe slower cars dont reach race temp because they're not race cars? The faster you go the more friction you make, no matter what you do a bicycle will never reach 200 degres. As for the burnouts, thats just strange. The second i lose control they go from about 165 to 225 almost instantly

[DougieManCan]

What class cars are we talking about? Im tuning a class B car, maybe slower cars dont reach race temp because they're not race cars?

Very true, the faster your going the more forces you'll encounter. As for lower classes they should come up to temperature just take longer to do it.

[BiggLou55]

I ran 6 laps on Infineon with my Mugen Type-R 3d (Class B - Full Aero & race tires), and the rear tires never got above 170dF @ 28psi... The fronts were running 190-205dF @30 PSI after the first lap, and stayed within 10dF between the inner and outer... I know the fronts are pretty good (might be able to use 1psi more), but I'm not sure if I should drop the rears down any further. I've adjusted the downforce distribution to go more to the rear to see if that helps, but I have not been able to test it yet....

[DougieManCan]

Dont forget this is a fwd car so the rear will never get to the same temperature as all the work is done at the front.

Im not sure but I dont think you will be able to change the setup enough to get them warmer. even turning abs off to try and lock them slightly wont work as the rears wont lock.

Also putting more aero on the back will lift the front of the car slightly as the centre of drag is moved further towards the rear, almost like a pivot.

[marmuttlebow]

Lou, for future, if you'd like, the ° symbol is "Alt+0176". That will put that symbol in your text.

For others, refer to the character map built into Windows (assuming you installed it, but is it an option?).

[BiggLou55]

Dont forget this is a fwd car so the rear will never get to the same temperature as all the work is done at the front.

Im not sure but I dont think you will be able to change the setup enough to get them warmer. even turning abs off to try and lock them slightly wont work as the rears wont lock.

Also putting more aero on the back will lift the front of the car slightly as the centre of drag is moved further towards the rear, almost like a pivot.

I will run a few test laps tonight with the the aero setup to the rear and see what, if any, differences come up. The Mugen is a very stable car, and it doesn't have much rear drift (unlike the mini which has a more unstable back-end)... I suspect the only difference I will find is reduced handling at speed....

BTW Low... That is not always the case... In Windows 7 it's not as easy to do ASCI input... typing dF is faster and easier! But just for you I will start using the Character mapper to use symbols and up the ° of difficulty when posting!

[DougieManCan]

As said before in a fwd car the rear wheels just follow the front, there is very little reason for them to warm up other than rear drift. on full sized racing you could try and put some rear toe-in on to try and get some artificial scrubbing of the rears, doubt you can do this on forza though.

[BiggLou55]

I have a question on Rim size in FM4.... I was working on my 6th B500 tune variant on my Stratos, and I stayed away from upping the rim size until now. What I noticed was interesting. when I upgraded the rim size from the stock 14" rims (yes 14") to 17" rims (went from 225/70-14's to 225/40-17), there seems to be a 2x payoff. The first is in the handling department (noticeably better/crisper) and in the speed department (made a pretty decent adjustment to final drive that increased my acceleration, but actually dropped 2 HP and 1 ft-lb in the tune).

My question is: Does rim size, or more specifically tire aspect ratio, play that big of a part in FM4? I know it does in RL, but I have not read anything about rim sizes in tuning guides. I've only seen reference to width and type.

[Insanefrank]

I have a question on Rim size in FM4.... I was working on my 6th B500 tune variant on my Stratos, and I stayed away from upping the rim size until now. What I noticed was interesting. when I upgraded the rim size from the stock 14" rims (yes 14") to 17" rims (went from 225/70-14's to 225/40-17), there seems to be a 2x payoff. The first is in the handling department (noticeably better/crisper) and in the speed department (made a pretty decent adjustment to final drive that increased my acceleration, but actually dropped 2 HP and 1 ft-lb in the tune).

My question is: Does rim size, or more specifically tire aspect ratio, play that big of a part in FM4? I know it does in RL, but I have not read anything about rim sizes in tuning guides. I've only seen reference to width and type.

It depends on the car, for some this works but not every car will be better.

[BiggLou55]

Thanks Frank.... It's seems to be working on the Stratos.... My guess is the drastically increased side-wall stiffness you get when going from 225/70-R14 to 225/40-R17 is the difference. I also noticed better tire heat patters and faster heating...

[Fischs3]

I just started to play around with trying to tune a car. My question is, why am I only able to change some of the areas on the car in the tuning section? For instance, on the Civic I was not able to change the gear ratios. This morning I was tuning an Alfa Romeo, I kept the class at F so I did not install many new parts to it. Then when I tried to change some of the tuning sections, the only option I had was to change the tire pressure. All other sections for lack of a better word were locked. Is there anyway around this? Is it dependant on the types of upgrades put on the vehicle? Any help would be appreciated.

[Markve91]

yep! aside from tire pressure tuning,you'll have to install the "race" version of the part that you want to tune

[BiggLou55]

As Mark pointed out... Race parts will provide full tuning. Since we are restricted to only Race Aero, Shocks/Springs and ARB, that's all you can control. To control the gear ratios, the race trnasimission in required and to control the limited slip the race diff is required.

Sport Suspension and Drivetrain parts will provide limited adjustments as well...

[Fischs3]

Thx guys.

[Fischs3]

This may be more of a computer question then tuning question but it involves Slave Monkeys Tuning calculator. I use a Mac and I am wondering if anyone else does? I watched the tuning tutorial and just before he starts the walk through at around 10 minutes video time he talks about loading the Analysis Toolpack. I have no idea on a Mac how to access this feature, is this needed for the program to work properly?

[marmuttlebow]

This may be more of a computer question then tuning question but it involves Slave Monkeys Tuning calculator. I use a Mac and I am wondering if anyone else does? I watched the tuning tutorial and just before he starts the walk through at around 10 minutes video time he talks about loading the Analysis Toolpack. I have no idea on a Mac how to access this feature, is this needed for the program to work properly?

To solve this problem, get a PC.

I don't know about Mac's. I thought there was something you had to activate something while using a Mac as well.

[BiggLou55]

This may be more of a computer question then tuning question but it involves Slave Monkeys Tuning calculator. I use a Mac and I am wondering if anyone else does? I watched the tuning tutorial and just before he starts the walk through at around 10 minutes video time he talks about loading the Analysis Toolpack. I have no idea on a Mac how to access this feature, is this needed for the program to work properly?

What version of MS Office are you running on the Mac...?

[swviper]

This may be more of a computer question then tuning question but it involves Slave Monkeys Tuning calculator. I use a Mac and I am wondering if anyone else does? I watched the tuning tutorial and just before he starts the walk through at around 10 minutes video time he talks about loading the Analysis Toolpack. I have no idea on a Mac how to access this feature, is this needed for the program to work properly?

I have a MAC Fischs, but I don't know which tuning tutorial you are talking about...I will have a look, and see if I can find it. If you have link, post it, and I'll have a look

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