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Carbon Fiber Driveshaft Points?


1LapAl

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I must be blind but I cannot find anything in the rules regarding carbon fiber driveshafts. The one I am considering is the exact same dimensions as stock but just made out of carbon fiber (lighter). The theory to this would be less drivetrain loss thus putting more power to the wheels. Any ideas on points for this modification?

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I must be blind but I cannot find anything in the rules regarding carbon fiber driveshafts. The one I am considering is the exact same dimensions as stock but just made out of carbon fiber (lighter). The theory to this would be less drivetrain loss thus putting more power to the wheels. Any ideas on points for this modification?

 

Since it is not a listed modification, technically it is illegal currently. Let me work on it. BTW, how much lighter is it than the OEM driveshaft on your car?

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I agree, but what is the difference between the shaft and say dropping 10 pounds off each corner by going with lighter wheels and tires? There are ZERO points assessed for that.

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Not that I ever intend on buying one, but it seems like if a lightweight flywheel and clutch are no points, and superlight wheels are no points, a lightweight driveshaft fits right in with the no point theme.

 

$.02

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I agree, but what is the difference between the shaft and say dropping 10 pounds off each corner by going with lighter wheels and tires? There are ZERO points assessed for that.

 

 

Because you can drop 10 pounds off each corner by going with lighter wheels and tires AND install lighter/stronger driveshafts and get even more performance.

Thats why!

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I must be blind but I cannot find anything in the rules regarding carbon fiber driveshafts. The one I am considering is the exact same dimensions as stock but just made out of carbon fiber (lighter). The theory to this would be less drivetrain loss thus putting more power to the wheels. Any ideas on points for this modification?

 

Since it is not a listed modification, technically it is illegal currently. Let me work on it. BTW, how much lighter is it than the OEM driveshaft on your car?

 

I am considering the ACPT carbon fiber driveshaft. The ACPT CF driveshaft weighs 13.5lbs, compared to 24.5lbs stock. The people I know that have dyno'd their cars with it haven't shown really any gains but like the response of their engine better (Similar to a light weight flywheel).

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Grey Matter,

Greg , This is an area for me that I see as a safty issue . The stock Mustang drive shaft is about 40 lb. & a 2 pc. cv type shaft . I am told that this is a weak shaft and will be replacing it about the end of the 07 season with a 1 pc. alloy drive shaft for saftey reasons only . There are about 3 brands avalible and also a carb. fib. ver. They save around 20 lb. My concern is not for points as is saftey . I think that as we have free gears , fly wheel , clutch ,wheels , this all sort of falls in the same line . but hey , we do have a lot of free stuff .Looks like I'll never make it back to TTC

Grey is just another shade of Black and White .

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Grey Matter,

Greg , This is an area for me that I see as a safty issue . The stock Mustang drive shaft is about 40 lb. & a 2 pc. cv type shaft . I am told that this is a weak shaft and will be replacing it about the end of the 07 season with a 1 pc. alloy drive shaft for saftey reasons only . There are about 3 brands avalible and also a carb. fib. ver. They save around 20 lb. My concern is not for points as is saftey . I think that as we have free gears , fly wheel , clutch ,wheels , this all sort of falls in the same line . but hey , we do have a lot of free stuff .Looks like I'll never make it back to TTC

Grey is just another shade of Black and White .

 

This is not a safety matter at all. Put a driveshaft loop on the thing if you think it's not safe. In fact, if you really think it's not safe, then why in the world would you take it on the track for a year, putting yourself and everyone else at risk? NASA actually has a policy that if a driver ever verbalizes or writes that he thinks that something "is not safe", then even if it is permitted under the rules, and everyone else is doing "it", the driver must either not participate in the "unsafe" activity, or in the case of a car part, MUST fix, modify, or replace the part so that he feels it is safe. If a rule prohibits such a modification, and the rule is not changed or waived, then the driver must simply not participate. NASA takes the safety of its drivers, as well as the driver's concerns for their own safety very seriously. Now, since you wrote three times that you are concerned for safety because of your driveshaft, I suggest that you either: 1) Do more research on the late model Mustang driveshaft (NASA is unaware of any safety issues related to it), and decide if you think it is safe or not, and report in writing here so that we all will know if your car is safe, or 2) Put a driveshaft loop on it to prevent it from flying if it breaks, 3) or both. I can guarantee you that Jerry will not let you on the track with the car as is, with the statements that you have made.

 

Now, as to the points cost of replacing the driveshaft, NASA still has not decided, but it is a performance issue, not a safety issue. If it was a safety issue, we would just require driveshaft loops on all RWD and AWD cars. We stopped assessing points for flywheels and clutches because we didn't want to have to tear down cars to inspect for lightweight flywheels and clutches, and a large majority of drivers will put one in after they fry the stock clutch anyway. There are too many possible variations of lightweight wheels and tires, and it would be a mess to figure out how much to charge for them, to weigh everyone's tire/wheels at the track, or to try and keep up with the weights of the hundreds of wheel models out there, and they are such a common modification, that we haven't charged for them. Now, changing out the driveshaft to a lightweight driveshaft is not terribly common except in open-type race classes, and it isn't difficult to inspect. And, if nothing else, it would be a free weight modification that FWD cars could not partake in. So, it will probably be assessed in some fashion.

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Seems fair enough. I'll certainly accept difficulty of policing as a reason for free vs. pointed mods.

 

Just please don't ever use the phrase "to keep costs down". We're in the wrong business fr that...

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Greg

I also take safety very serious . My concern stems from the drag guys with blowers . I really think that the stock shaft is fine at OE HP levels .

They are made for a car that see's normal driving . I mentioned this only for future alterations that might come at a later date that would require investment in parts that would hold up better under the stress of road race use . , I feal that my car is as safe as any on the track but that doesen't mean that I think it is safe enough for my personal comfort level. Ilike to look ahead in planning the upgrades to try and prevent buying things twice , and planning the build to progress into another form of compatition. I like the fact that NASA takes the safty issue serious. I wish I could buy all the safety devices , fuel cell, Han's , full blown cage , seat , shoes , fire supression , and Hollow Deck , all at once . That is a little unreal in regards to my budget . Take a brain bucket , you will never see me in some of the cheep brands that NASA accepts . That is a personal safety choice . My car is going in for a full containment seat and a 6 or 8 pt . Both to help lap times . I could use a cheep seat , and fab the bar myself and all would work just fine . Because my safety is most important to me , I chose to have a pro. install the roll bar or cage , and install the best seat I can fit in my budget . I dont at all think that my drive shaft in UNSAFE. just that along with the safety hoop a stronger shaft is just another part that would add to the package .

I really could care less if points are added . I will install a hoop before our first event . I guess I should listen to my friend and just keep a low profile and stay out of radar range . But thats no fun for me .

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Ok, here's what we are going to do--stick with the current rules. If you have a lightened driveshaft, you will need to use the alternate method for assessing weight reduction points (since it is lightening that is not otherwise assessed points, and is not on the list of No-Points Modifications). We will not be assessing the potential improved performance aspect due to decreased rotational mass.

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