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Discussion Starter #1 (Edited)
Wheel Fitment Spreadsheet!
Right click, save as =)

I've noticed that a lot of people are having issues with this whole "does it fit?" thing ... so I made a spreadsheet. However, I don't know where to host it up. Anyways, I tried to make everything as easy as possible ... put in your wheel size, tire size, and camber and the spreadsheet will spit out an answer as to whether or not they'll fit.

Edit: It's setup for the inner lips of the fenders that have been rolled, so if you're going for a moderate look ... well, this spreadsheet will still help =P

Edit v2: Here's the link! Thanks Longnights!
 

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Dunno where you can host, but just wanted to say nice job. I'm surprised by the amount of people who can't figure out how to do the math or are too lazy to do so. +rep.
 

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Discussion Starter #3
Thanks man! I'm working on a way to figure out if it'll fit depending on how low the car is ... basically if the tire or the wheel width is the deciding factor on if everything is going to fit.
 

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wow i'd like to see this. i've tried to help a ton of people. but really i dont know THAT much about fitment. i just go by the equation and what i've read about other people running. i think that would help a lot of people out.

and i agree Johnny. there are WAY too many people here who cant figure out the math or are too lazy to do it.
 

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I can host it. You've got a PM.
 

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Discussion Starter #6
Link Posted! Any suggestions, comments ... send them my way! My email is on the bottom of the sheet.
 

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The math for the rim part looks good to me. I didn't check the tire part nor the if conditions. This should probably be stickied if no issues are found after a while? Good job!
 

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overall i think it is a great tool to use i think it might be a little off on the suspension part because with my current setup which fits with no issues it says i need a spacer...
 

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Discussion Starter #9
Yeah, that wasn't looking right to me either, but I used the numbers from the stickied post ... so I dunno? When I get home in 2 weeks, I'll remeasure everything ... and try some 18x9/10 +20's on there and see how stupid that looks =P
 

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When I get home in 2 weeks, I'll remeasure everything ... and try some 18x9/10 +20's on there and see how stupid that looks =P


I joke ..... :p His car look good except for all the ding's and crack's.
 

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Nice spreadsheet, but needs to be tweaked a bit. Using my current setup, it says my front fenders need to be pulled .21 inches.

18x7.5 +42 with 225/40/18 all around, and -1 camber. Those things look as sunk as the Titanic.
 

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Discussion Starter #14
Yeah, I don't know why some work and others don't. like I said, I used the numbers from the sticky up top ... If anybody wants to help me out and get this thing closer, then I think a couple of us need to measure the hub to fender and hub to suspension distances and see where the discrepancies are. The more measurements we can pull together, the better this spreadsheet will be. Hell, maybe we can update this thing to factor in the year of the car!

Well, I'm thinking that that measurements in the sticky were made with the suspension at full droop, but don't hold me to that. After finals (1.5 weeks for me), I'll get the car in the air and make sure the measurements are correct =)
 

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I'm not sure how to fix it, but I think it may be related to camber. When I change camber from -1 to -10, I only gain .07 inches of clearance.

-1 degree camber: -0.21 inches Pull Fender
-10 degrees camber: -0.14 inches Pull Fender

Also, changing the wheel width from 5 inches to 10 inches only changes the "Pull Fender" computation by 0.57 inches.

Hopefully that will be of some use to you.
 

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Yeah, I don't know why some work and others don't. like I said, I used the numbers from the sticky up top ... If anybody wants to help me out and get this thing closer, then I think a couple of us need to measure the hub to fender and hub to suspension distances and see where the discrepancies are. The more measurements we can pull together, the better this spreadsheet will be. Hell, maybe we can update this thing to factor in the year of the car!

Well, I'm thinking that that measurements in the sticky were made with the suspension at full droop, but don't hold me to that. After finals (1.5 weeks for me), I'll get the car in the air and make sure the measurements are correct =)
GREAT work on this. Since you are going to be doing a FRC sheet next ;) you may want to measure the wheel motions when you have it up in the air. I think all we need are the sway bar motions as the wheel motions have been posted.
 

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Discussion Starter #17
Update: I need to fix some problems, then upload a new version of the file.

So I figured out the camber problem ... I forgot to change from inches to mm ... I always forget some mundane detail. I also fixed the "overall tire height" cell. Oh well, the camber corrections work now, so now I'm hunting down other problems (like why some people's wheels are sunk in and why the spreadsheet is telling them they need to pull the fenders).

What's an FRC sheet? And how should I go about measuring the sway bar motions? Is it from a fixed point on the car? or a point in space?
 

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FRC (front roll couple) or also could be mentioned as the Body roll calculator. Here's a good sheet that someone put together that uses a wide range of known automotive calculations to determine how a car will react with specific modifications.
Weight transfer, spring frequency, damper, body roll calculator... and more! - NASIOC

Here's a good link that tells a little about measuring motion ratios

http://www.shock-shop.com/Critical Damping/Taking CDA Measurements.pdf

Kinda PITA to get the measurement though. I'm sure these measurements are in some racing datalog somewhere though.
 

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Good enough until someone puts up something better.
 
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