Suspension Analysis Calculator & Transmission Calculator

[Poontanir]

Tuning is a subtle science and exact art. This calculator is to help with the subtle science; the exact art you must provide.

I have made this calculator to help with understanding the results of Suspension tuning in respect to weight, weight distribution, downforce, and many other factors. The gear ratio calculator will provide better use of the power band.

Any questions, comments or help is welcome. Please don't PM me with questions, I want others to learn from all questions asked. The file has two sheets on it one for suspension calculations and the other for the drive train. Instructions and explanations are in text boxes on their respective sheets.

I have created an HTML/javascript version of the calculators to make it more accessible. These pages aren't good looking but they do work (just not with IE). I welcome anyone to make adjustments to the look.

The excel sheet is locked with the password "granturismo". I did this so one could use it without worrying about breaking it. Please if you make adjustments share them and explain them. I would like to keep an updated calculator on this first post, so if you want to add to it let me know. The setup sheet is an older version I have kept around because some of the latest features are a bit confusing.

Update 2012-03-23
improved damper modeling
created HTML versions
removed LSD calc (not enough tire info)

Update: 2012-02-04
Reworked Anti-roll and Camber Section again
* If you liked an older version, they are now available

Update: 2012-01-10
Cleaned up trans calculator
added 1st gear select trans calculations
corrected some crossed variables
corrected unit errors in damper model
simplified ARB & camber Section
updated instructions and explanations

Update: 2012-01-07
Made speed calculations for Trans calc easier to use
Improved in file instructions per questioned asked

Update: 2012-01-06
A working model of the effect of damper
camber math fix (no more crazy numbers)

Update: 2012-01-04
better instructions (I hope)
Improved camber math and simplicity

Update: 2012-01-04
rearranged anti-roll bar and camber inputs for easier use
Fixed anti-roll bar and camber math
Improved Spring Oscillation modeling

Update: 2012-01-03
Revamped suspension calculator
Added Spring Oscillation Model for damper settings
Added Anti-Roll bar and Camber Calculations

Update: 2011-12-30
Added Experimental LSD Calculator

Update: 2011-12-30
Improved Descriptions
added speed calculation to trans calculator
basic instructions for trans calculator

 

[Lambob]

please explain stock ride height setting, and the red % Suspension Travel Usage, thank you

 

[Poontanir]

please explain stock ride height setting, and the red % Suspension Travel Usage, thank you

The Stock Ride Height is to calculate an absolute ride height as opposed to GT5's -10 to 10 ride height adjustment. Basically the car's absolute ride height when the ride height adjustment is at zero. I wish there were a simple database to reference this but I haven't found one, otherwise I would have put a link. I referenced GT4 for the Formula GT which was 40mm at 0.

The Suspension Travel Usage is a rough (don't make me say it again) rough estimate as to if the setup will bottom out over a bump. 100% being bottomed out. If you run stiff bound setting (damper compression) you can run close to or over 100.

Sorry this wasn't clear but that is part of what I'm trying to work out. The other part is some of the math be hind the estimates. I'm hoping to work the damper settings into the math as well.

 

[Poontanir]

Experimental LSD Calculator
I have added this to the sheet I don't know if it will be worth anything but I welcome all feedback. My goal is to create some useful tools to aid setup.

 

[Poontanir]

New Features, feed back welcome.

 

[Corpsey]

I like the setup sheet suspension calculator, the Setup Calculator one is too complex.. could you describe the inputs a little better maybe in the main post? Good work though.. the suspension calculator worked really well.

 

[Poontanir]

I like the setup sheet suspension calculator, the Setup Calculator one is too complex.. could you describe the inputs a little better maybe in the main post? Good work though.. the suspension calculator worked really well.

I haven't put directions in the main post for the calculator file mainly because I'm still doing a lot of shake down with it. Once I have it all worked out I'll add better instructions.

Anyone interested in helping, but not wanting to get into the math could post setups they have gotten from the calculator and adjustments made that made improvements with what improvements the adjustments made (along car specs so I can plug them in), it would be a big help. I can only do so many test for myself.

 

[Poontanir]

Big news ... but first an apology. I withheld a fix to the math for the camber recommendation, that is till now.

Now the BIG NEWS.
Our early attempts at a suspension damper model went through several preparations. Preparations A through G were a complete failure. But now, ladies and gentlemen, we finally have a working suspension damper model, which we shall call ... Preparation H.

The only things left for me to do is rework the LSD calculator, improve my instruction and kill any bugs.

 

[Adrenaline]

Anyone recall what AssassinTuner ended up getting banned for? I missed that one.

 

[Poontanir]

A Question I thought was worth sharing ... If you have any question please ask them in this thread so I can answer them for everyone and only need to look in one place for how I need to improve my instruction or calculations.

Hi Poontanir, your setup calculator is very interesting for me...good job 👍
but i don't understand very well the colours when i put dampers setting. What mean when the estimate minimum clearance became red? it is a good or bad result?
another question about the graph...for a good result, the two curves must be similar as the example you've done?....
however, you're really doing a good job ....

Estimated minimum clearance is trying to predict if the car will bottom out. When you use a lower damper number (damper rate) the spring is compressed more making it more likely to bottom out. Simple answer, red is bad. All of this is meaningless if you have the wrong Base Ride Height entered.

As far as the damper curves I'm not entirely sure. Having them bottom and top about the same I believe is a good thing but this all depends on your tuning philosophy and purpose. For example for a passenger car you would tune for comfort leading you to aim for a level ride. For an F1 car your aim might be to keep the car in a good position for aero performance. Sorry I can't be more helpful, but my goal was to make it easier to know what the car is doing and if you know what you want find a good starting point; so I don't have all the answers.

 

[David McMahon]

Should there be a download link here? New user so please go easy on me! I can't find in the Library section either, assume it is there?

 

[oregonpanda]

I don't see a download link or link to HTML website either. Please toss me and David some pearls, we promise not to rend you.

 

[Eiskalter Mick]

The last update was 4 days ago, my guess is the old link was removed and a new link, not yet posted.

 

[3spddrft]

This is exciting. I love excel :-)

 

[dminorkid]

I was going to use this, but no link?

 

[prgt77]

Poontanir...dude where is the link for this. This looks like it will be very useful

 

[dustin862]

Poontanir when are we going to get a download link for this man?

 

[Furinkazen]

Poontanir when are we going to get a download link for this man?

He's not been on since March and your bumping a very old thread..

 

[hhhaaa]

Looks like he is another one of those (blablablablabla) ones.

 

[xande1959]

anyone recall what assassintuner ended up getting banned for? I missed that one.

as it happened