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RichardP
10-02-2007, 02:11 PM
I brought this up last year at this time. It seems likely that I’ll bring it up again next year about this time… :)


After some issues at Nationals last year, the CMC rules covering fender rolling and modifications were strengthened considerably to try and keep track widths under control. Despite these changes, the allowed track width of a CMC car is still based subjective visual inspections of curved shapes. This is on cars some of which are over 25 years old and have led a very hard life.

Track width is too important of a performance parameter to be subjectively evaluated by an inspector that could come up with a different answer than another inspector reading the same set of rules. The line between someone completely following the intent of the rule and someone pushing the rule a little too far is very blurry.

Creating a numerical track width allows for an easy, non-subjective evaluation of the legality of a competitor. The measurement can quickly be done using tools many competitors already possess. The American Iron series has already grappled with this issue so the tools to measure it should also already be in the tech shed.


Richard P.

Al Fernandez
10-02-2007, 10:48 PM
I think in this scenario the issue is not so much how to measure it, but rather what to set the number to. In AI its an easier story since bodywork modifications are allowed. So, if this were to fly...what should the different widths be?

GlennCMC70
10-02-2007, 10:57 PM
the main problem w/ this is by limiting track width, you can limit camber on a 4th gen being as its adjusted w/ the lower A arm. this would not be the case w/ the Fords or the 3rd gens. i just wanted that to be known.

Al Fernandez
10-02-2007, 11:00 PM
Right you are Glenn...you might limit camber, depending on the width selected, and the competitor's wheels... so the point still is: what could/should the magic numbers be?

Todd Covini
10-02-2007, 11:12 PM
The magic numbers should be wider for Ford.

http://images.jupiterimages.com/common/detail/20/78/23497820.jpg

michaelmosty
10-02-2007, 11:37 PM
I don't know, I'm still wondering what the front track-width is on the 3rd and 4th gens.

mitchntx
10-03-2007, 06:06 AM
I don't know, I'm still wondering what the front track-width is on the 3rd and 4th gens.

You have a 4th gen sitting in your driveway and I assume you have a tape measure.

Or do you want the GM camp to give that to you as well?

RichardP
10-03-2007, 07:57 AM
I think in this scenario the issue is not so much how to measure it, but rather what to set the number to?


Maybe we could measure the current cars. Pick three of each eligible model that by the current rules “appear” to be at their maximum width. If you get the same measurement for all three cars, then use that number. When you don’t get the same number, you have validated the need for this rule clarification and you get to make an executive decision.

Realistically, the number you are supposed to pick is the widest number you get that still meets the arbitrary “looks right” test. The intent is not to change anything or anybody’s car. There should be no cost to the organization or the competitors for this. It’s just a way to take judgment out of the process and make sure everyone is meeting the same standards.

Where we are currently, you can have a guy that has maximized his car to what he believes is the extent of the rule but is actually at an unknown disadvantage to the guy who has done a better job at “tweaking” his car.

Within the next month, there are events at Barber, Thunderhill, and MSRH that I know of. I volunteer to measure the entire CMC field at MSRH and create a spreadsheet if you would like. There is a 50/50 shot that I will be at Barber. If I go, I’m happy to do the same at that event, too.


Richard P.

mitchntx
10-03-2007, 08:21 AM
As Glenn pointed out, Richard, the flaw is measuring a 4th gen.

Camber is set by moving the lower A-Arm in and out.

I have a different camber setting for TWS, Houston and Cresson. Tracks that require more brake, I use less camber (more tire contact patch). Tracks that have higher speeds, I use more camber (less rolling resistance).

So, my track width might vary 1/2" or more.

RichardP
10-03-2007, 08:35 AM
Track width changes with camber on a Mustang too.

So we set the number so that at maximum negative camber you meet it. When you run less camber, you are effectively allowed to use 1/4" wheel spacers. Or it becomes a tradeoff in setup that competitors have to balance. Whatever needs to happen. The current rule is not really a rule at all.


Richard P.

michaelmosty
10-03-2007, 09:05 AM
I don't know, I'm still wondering what the front track-width is on the 3rd and 4th gens.

You have a 4th gen sitting in your driveway and I assume you have a tape measure.

Or do you want the GM camp to give that to you as well?
Pardon me for being so stupid Mitch. If I had a stock 89 Mustang in my driveway I wouldn't use its measurement b/c it is completely different from a race car. I have no clue what the 4th gen. guys do to your front suspensions.
Since I assume from your statement that your track width is the exact same as my street car I will walk out onto the driveway and measure. I wouldn't want you to do too much work for me.

y5e06
10-03-2007, 09:55 AM
I don't know, I'm still wondering what the front track-width is on the 3rd and 4th gens.

from the top of my head, with stock salad shooters, ~-2.2* camber, and no wheel spacers I believe I'm around 73.25 - 73.5". This is when setting up toe using my longacre toe plates, so true numbers may be slightly higher since this measurement is at the tape measure slots in the plates, possibly not at the max width of sidewall.
I'm now running 1/2" spacers on the front. I'll be measuring again within the next few weeks when I work on getting setup for MSRH.


now get rid of those wings...

michaelmosty
10-03-2007, 10:01 AM
Thank you for the reply Morgan.

I can type small too. :lol:

y5e06
10-03-2007, 10:03 AM
also, the numbers specified should be different for each platform given the stock dimensions are inherently different, ala AI rules.

for completeness, AI rule:

Fox and SN95 Mustangs and Capris are allowed a maximum wheelbase of 102.2 inches and the wheelbase for all other AI vehicles shall remain within two and one-half (2.5) of the original factory configuration. Fox and SN95 chassis vehicles are allowed a maximum allowable wheel width of 72.5 inches (measured at the outside edge of the tires). GM 4th generation F-body chassis vehicles are allowed a maximum allowable wheel width of 75 inches (measured at the outside edge of the tires). Ford S197 chassis vehicles are allowed a maximum allowable wheel width of 74 inches (measured at the outside edge of the tires). All track width measurements shall be conducted using a straightedge such as a tire alignment plate to determine the measured width.[/i]

jeffburch
10-03-2007, 10:26 AM
Rules are bad.

Track width as it is now is perfect, except the foxes need help.
Allow a 1" (or so) flare on the fender and call it good.

Minimum weight for Foxes is 3100.
Let the minimum for 3rd gen f-bodies be 3125 and 4ths be 3175.

I like Adams take on the aero. Throw them all the hell away, mine included. If it wasn't a factory authorized dealer add on forget it.

Less rules the better.

If you pay close attention to the videos out there, these cars are SOOOooo slow it's almost painfull to watch them.
They do not need aero stuff.

jb

GlennCMC70
10-03-2007, 10:31 AM
3175 is impossible to get to w/ a 4th gen. you didnt give it if it aint attainable.

AllZWay
10-03-2007, 10:44 AM
Throw them all the hell away, mine included. If it wasn't a factory authorized dealer add on forget it.

Less rules the better.
jb

yep... I agree.

jeffburch
10-03-2007, 12:20 PM
3175 is impossible to get to w/ a 4th gen. you didnt give it if it aint attainable.

Good, throw out the weight rule entirely IF your car makes the max hp/tq numbers.
Leave the over the max stuff alone i.e. over hp/tq = more weight.
I'm tired of weighing.
2 lbs here and there don't mean diddly.
jb

Fbody383
10-03-2007, 01:48 PM
8.34. Wheels/Tires
8.34.1. All cars may use any one piece or two piece wheel that weighs more than 16lbs.
8.34.2. Maximum wheel size is 16”x8” for CMC and 17”x9.5” for CMC-2.
8.34.3. Maximum tire size is 255/50R16 for CMC and 255/40R17 for CMC-2. The only tire brand and model allowed is the Toyo Proxes RA-1.
8.34.4 Wheel spacers are allowed and wheels may have any offset.

Why not limit the wheel offset and spacer thickness by make/model and not worry about measuring track width?

I tried to capture the same 2006 to 2007 change highlight in the rules at the CMC site.


I like Adams take on the aero. Throw them all the hell away, mine included. If it wasn't a factory authorized dealer add on forget it. I'll add a vote to this too.


Good, throw out the weight rule entirely IF your car makes the max hp/tq numbers.
Leave the over the max stuff alone i.e. over hp/tq = more weight.
Everybody tells me the last several (many) pounds don't matter and that driver matters more. If you're AT or UNDER max hp/tq can you legally get the car light enough to matter?

cobra132
10-03-2007, 09:58 PM
The AI rules for wheelbase and track width are to complicated and not equal. Fox and SN95 have a max wheelbase of 102.2, all others must be within 2.5 of stock. My SN95 stock is 101.3 yet I am limited to 102.2. Wheel width: Fox/SN95 = 72.5, S197 = 74, GM = 75.

Keep it simple. For AI: Wheelbase must be within 2.5 inchs of stock and maximum track width is 75 inches. One line. FMR

GlennCMC70
10-03-2007, 10:04 PM
since the GM is a longer car over all (nose to tail) its only fair to allow it to be wider too.

Todd Covini
10-03-2007, 10:16 PM
Longer + wider = "it's only fair to make it heavier too"

marshall_mosty
10-04-2007, 07:21 AM
since the GM is a longer car over all (nose to tail) its only fair to allow it to be wider too.

Glenn,
I can hang 3" of polyurethane bodywork off my car and call it longer too... what does overall length have to do with track width?

For our cars, more wheelbase and track width helps. GM already has a longer wheelbase AND trackwidth...

what are you getting at?

GlennCMC70
10-04-2007, 07:37 AM
working traffic in a wider longer car has its disadvantages. w/ the cars side by side w/ the nose's even, there is 2 ft of GM sticking out past the Ford. the GM will have to travel the greater distance to complete the pass.
the sum of it is, a Fox will fit in places a GM will not.

AI#97
10-05-2007, 02:24 PM
The AI rules for wheelbase and track width are to complicated and not equal. Fox and SN95 have a max wheelbase of 102.2, all others must be within 2.5 of stock. My SN95 stock is 101.3 yet I am limited to 102.2. Wheel width: Fox/SN95 = 72.5, S197 = 74, GM = 75.

Keep it simple. For AI: Wheelbase must be within 2.5 inchs of stock and maximum track width is 75 inches. One line. FMR

Just to keep things straight....the max wheelbase is 102.5...rules clarification for 2007 because it was found that EVERY maximum motorsports equiped AI car was illegal by .3 inches!!! Whoops!!!

I too have always not liked the fact that GM's can be so wide compared to Mustangs but without F-bods in AI....it's difficult to tell if it's an advantage or not.

And for the record, mine is 72.25 wide per the new measuring technique above the ground, and 102.5 inches of wheelbase exactly. :wink:

AI#97
10-05-2007, 02:27 PM
I brought this up last year at this time. It seems likely that I’ll bring it up again next year about this time… :)


After some issues at Nationals last year, the CMC rules covering fender rolling and modifications were strengthened considerably to try and keep track widths under control. Despite these changes, the allowed track width of a CMC car is still based subjective visual inspections of curved shapes. This is on cars some of which are over 25 years old and have led a very hard life.

Track width is too important of a performance parameter to be subjectively evaluated by an inspector that could come up with a different answer than another inspector reading the same set of rules. The line between someone completely following the intent of the rule and someone pushing the rule a little too far is very blurry.

Creating a numerical track width allows for an easy, non-subjective evaluation of the legality of a competitor. The measurement can quickly be done using tools many competitors already possess. The American Iron series has already grappled with this issue so the tools to measure it should also already be in the tech shed.


Richard P.

richard, don't take this the wrong way but why stir the pot in CMC when you don't have a CMC car?

Shall we name you the caped crusader for the whimpy CMC mustang drivers? What is your intent?

cjlmlml
10-05-2007, 02:52 PM
Matt ,

Dont take this the wrong way.



Neither do you , so why are you posting here?

I myself, do have a CMC car, oh wait a minute......................................

Good bye. ( in closing down computer voice)

michaelmosty
10-05-2007, 03:05 PM
I myself, do have a CMC car, oh wait a minute......................................


:shock: Fresh meat? :twisted:

RichardP
10-05-2007, 03:18 PM
I myself, do have a CMC car

Very cool.


Richard P.

AI#97
10-05-2007, 04:54 PM
Matt ,

Dont take this the wrong way.



Neither do you , so why are you posting here?

I myself, do have a CMC car, oh wait a minute......................................

Good bye. ( in closing down computer voice)

From what I hear your car is all one color now and sporting a VERY nice power plant! Get some aero and start playing again!!!! :wink:

Todd Covini
10-05-2007, 07:41 PM
I brought this up last year at this time. It seems likely that I’ll bring it up again next year about this time… :)


After some issues at Nationals last year, the CMC rules covering fender rolling and modifications were strengthened considerably to try and keep track widths under control. Despite these changes, the allowed track width of a CMC car is still based subjective visual inspections of curved shapes. This is on cars some of which are over 25 years old and have led a very hard life.

Track width is too important of a performance parameter to be subjectively evaluated by an inspector that could come up with a different answer than another inspector reading the same set of rules. The line between someone completely following the intent of the rule and someone pushing the rule a little too far is very blurry.

Creating a numerical track width allows for an easy, non-subjective evaluation of the legality of a competitor. The measurement can quickly be done using tools many competitors already possess. The American Iron series has already grappled with this issue so the tools to measure it should also already be in the tech shed.


Richard P.

richard, don't take this the wrong way but why stir the pot in CMC when you don't have a CMC car?

Shall we name you the caped crusader for the whimpy CMC mustang drivers? What is your intent?

Adam...forget what I said earlier. It's open season. :roll:

GlennCMC70
10-05-2007, 10:51 PM
richard, don't take this the wrong way but why stir the pot in CMC when you don't have a CMC car?

Shall we name you the caped crusader for the whimpy CMC mustang drivers? What is your intent?

did you mean "wimpy"? :?

AI#97
10-05-2007, 11:02 PM
richard, don't take this the wrong way but why stir the pot in CMC when you don't have a CMC car?

Shall we name you the caped crusader for the whimpy CMC mustang drivers? What is your intent?

did you mean "wimpy"? :?

Just following your lead brother!!! :lol:

RichardP
10-10-2007, 08:40 AM
Within the next month, there are events at Barber, Thunderhill, and MSRH that I know of. I volunteer to measure the entire CMC field at MSRH and create a spreadsheet if you would like. There is a 50/50 shot that I will be at Barber. If I go, I’m happy to do the same at that event, too.


OK, so I will be at Barber. Am I supposed to be measuring any CMC cars?


Richard P.

mitchntx
10-10-2007, 08:42 AM
Make sure you get your forearm calibrated before you go.

donovan
10-10-2007, 10:40 AM
Within the next month, there are events at Barber, Thunderhill, and MSRH that I know of. I volunteer to measure the entire CMC field at MSRH and create a spreadsheet if you would like. There is a 50/50 shot that I will be at Barber. If I go, I’m happy to do the same at that event, too.


OK, so I will be at Barber. Am I supposed to be measuring any CMC cars?


Richard P.

Will your car be there???
DD

RichardP
10-10-2007, 11:12 AM
Will your car be there


No...


Richard P.

donovan
10-10-2007, 12:02 PM
:(

RichardP
12-12-2008, 03:31 PM
I brought this up last year at this time. It seems likely that I’ll bring it up again next year about this time… :)


After some issues at Nationals last year, the CMC rules covering fender rolling and modifications were strengthened considerably to try and keep track widths under control. Despite these changes, the allowed track width of a CMC car is still based subjective visual inspections of curved shapes. This is on cars some of which are over 25 years old and have led a very hard life.

Track width is too important of a performance parameter to be subjectively evaluated by an inspector that could come up with a different answer than another inspector reading the same set of rules. The line between someone completely following the intent of the rule and someone pushing the rule a little too far is very blurry.

Creating a numerical track width allows for an easy, non-subjective evaluation of the legality of a competitor. The measurement can quickly be done using tools many competitors already possess. The American Iron series has already grappled with this issue so the tools to measure it should also already be in the tech shed.


Richard P.


After being suggested several years ago, there is now an actual track width measurement for Fox Mustangs in CMC2. What a cool concept.


The actual measurement is a bit curious. They just grabbed the width from the AI rules at a current 73.25". Wow, that's wide. That's serious fender butchering wide.

For those who remember how butchered up my Fox fenders were, they were only covering up a 72.5" track width that was in effect when I won the AI championship. Actually, that's realistically wider than you can get a SN95 car within the CMC fender modifying rules. How funny is that. :D And the Foxes still get the 50# weight break from the SN95’s in CMC2. Cool!?! I might suggest some subtle adjustments there even though I'm pleased with the progress.


Unfortunately, all the other platforms still go off of beat up body work to determine legality. Since the concept of a width measurement has now been accepted, that just seems lazy. Sigh... Oh well, baby steps.

I was at the track recently where there was a discussion about the legality of a particular CMC car based on the body work. That’s right, subjective measurements of critical suspension parameters based off of floppy plastic panels on a 15 year old car that’s been in numerous incidents including time on it’s roof. I still don’t get it but maybe there is hope for the future…


Richard P.

michaelmosty
12-12-2008, 03:38 PM
I agree Richard, I would like to see a # in the rules for max width, for all platforms.
FWIW, I heard Matt King's SN95 had a front track width of 73.25" at Nationals. I'm not sure if that is where they got the # though.

donovan
12-12-2008, 04:02 PM
My AI car is at the limit now and it does not fit under my Tiger Racing fenders without significant modifications. People at nationals got to see it and many people questioned if it was legal!!! 73.25 on a Fox is very wide!!

Al Fernandez
12-12-2008, 05:16 PM
73.25 is pretty wide for a fox. However, there are plenty of examples of SN95 cars getting up to 73 with RA1s and no fender mods. That is why we picked the number; if you get the fox that wide then its practically an SN95. The extra 1/4" is an allowance we threw into AI since the 888s have a bit more at the shoulder, so we figured we'd stick that into the CMC limit as well.

ShadowBolt
12-12-2008, 05:33 PM
Thanks Al!

JJ

AI#97
12-12-2008, 11:19 PM
73.25 is pretty wide for a fox. However, there are plenty of examples of SN95 cars getting up to 73 with RA1s and no fender mods. That is why we picked the number; if you get the fox that wide then its practically an SN95. The extra 1/4" is an allowance we threw into AI since the 888s have a bit more at the shoulder, so we figured we'd stick that into the CMC limit as well.

SN99 cars can probably go to 74.5 in teh front and probably 80 in the rear...kidding on the rear but serious on the front. I have tucked 73.5 easily on my car! Maybe Jeremy will do well...? :oops:

Rob Liebbe
12-12-2008, 11:42 PM
Thanks for the track width, but simply saying Fox bodies can have the same track width as SN95's is not as easy as it sounds. The later cars had much more generous fenderwells. I guess we'll see how far us Fox guys can push the limits of fender mod and appearance.

I know it is a miximum track width rule, but you can't allow the improvement ( track width) one one hand, but disallow it with the other (no fender mods allowed).

Discussion will follow and I'm sure we can figure this out.

Al Fernandez
12-13-2008, 12:17 AM
Rob, the numeric width limit for foxes only applies to cmc2 cars. cmc1 rules for width have not changed.

Jeremy Gunter
12-13-2008, 01:54 AM
SN99 cars can probably go to 74.5 in teh front and probably 80 in the rear...kidding on the rear but serious on the front. I have tucked 73.5 easily on my car! Maybe Jeremy will do well...? :oops:

Wait one min... I kept my mouth shut, minded my own business, and MFW (a Team SCHWING member) throws my rookie ass under the bus. Thanks bro. :wink:

If for some strange reason I do well, I will blame it on the track width... 8) whatever happened to all this talk about seat time?