I have messed around with this thing now and now that I am learning how to use it, I have figured out that it works well. It takes in all the specs of your car (have to do some deep searching to find them all) and gives you a tune. here is a link to where it can be downloaded.
http://forums.forzamotorsport.net/forums/thread/3200749.aspx

This is asking for alot trooper but could do a screen capture and explain what certain things mean if you know off hand or your understanding.

i see a lot of the info is on the 6th or 7th tab about tire width etc.

ill be on tomorow, im still figuring it out myself, i can help u find all the info for your car tho. myself and aero were tinkering with it today.

This is the same Calculator that I've posted in our Team section a few times.

The best way to get aquainted with it is to go to the link that trooper has posted and download the spreadsheet and read the instructions in the thread.

there is also a Tire/car width guide to download and use. This guide will be incorporated in the Tuning gude soon, so that you woun't have to hunt for the info.

Even the trans calc works with all info entered.

I've been using these guides originally provide by Feuerdogg, since Forza 1.

Happy tuning everyone.

i watch the tutorial... but i dont understand

Basically, you have to fill in all the data on the left (input) side of the spreadsheet. The numbers calculate automatically.

well im gonna try again...

Here's the instructions from FM.net:

To tune any car make sure you are in it and go to:

1. Main Menu>cars>my cars
2. press y to toggle.
3. input that data into FM-TC Main(ie; power, torque, weight, front)
4. press x (car list)
5. Hold the LB until you reach the data needed (ex: power rpm, torque rpm, redline rpm, front and rear tire sizes)
6. Enter required data into FM-TC Main
7. Go to Tuning>Upgrade Shop>Wheels to get Leteral G's. Its shown on the confirmation-Screen if you purchase Wheels. If already mounted any, select Stock rims, press A once check Value in the "before" sector to get the current Value, then abort mounting with B.
8. Enter results into the game and benchmark test for top speed and enter it in cell D30, input>trasmission>top speed. Readjust gears to top speed desired.
9/ If aero parts are installed, write the maximum values into advanced>aero>Maximum Downforce. Adjust strength and front bias at your own risk.

Follow the comments inside the modifier cells for guidance to that tweak you are looking for.

ok thanks!

nop

i only see ######################

and ¿NOMBRE?## or something like that and i cant select any thing only in the 1st page

Romaza the 1st page where u put in the pi and HP and torque is the only page u can input information besides the transmission sheet u can switch how many gears u want

i put the information but it doesn't appear anything

When u put the pi number in does it change