Help with clasification

[Cbntmn]

Im a vette driver and im thinking about running my first NASA event at Roebling this month.

 

While I currently have a vette that ive been told would fit into TTS, im a little confused about the points system and clasifications.

 

I am also looking at purchasing another z06 that is more of a track oriented car. It has more mods than the current z has, but again im a little confused about the clasification.

 

Is there someone I can talk to/e mail that can give me a hand reasoning this out? I hate to purchase a car that i have to "detune" to get to a certain class.

 

Thank you in advance for your help.

[jvetthead]

Well, Myfirst post here also my first NASA event last weekend..I'm hooked.

simply put..it comes down to power to weight ratio. For TTS,U R you need a dyno sheet and a wiegh in..I just classed in TTU with 8.2 lb/hp

Ther are a few more details but thats what it comes down to....

[kbrew8991]

if you know the weight, power, and tire size & type you'll compete on, doing your TTS/TTU classing is just a bit of math away.

 

Post the details you know, and I'll help you out with it

[Cbntmn]

Thanks for your help guys.

 

The car im looking at purchasing is a 01 Z06. It weighs in at 3125 and I weigh 250. HP at the rear wheels is 440

 

Mods are as follows:

Engine:

Headers

high flow cats

Aftermarket cat back

Different cam

heads massaged

 

Wilwood rotors/calipers/pads

 

Lowered

coil overs

larger sway bars

 

 

Tranny cooler

oil cooler

larger radiator

 

Rear spoiler. Attached to trunk and about 3" total height

front spliter/spoiler

 

Sarco seats

5 pt roll cage

5 pt harnesses

 

Stock tranny

 

I think thats about it. Im sure it puts me up at least one class but I was hoping to stay there. Im sure as i get farther into this ill understand the rules a little better.

 

Thanks for your input

[kbrew8991]

you're pretty solidly in TTU at 7.67 power:weight ratio with that car.

 

The good news is theres alot of room for more power, less weight, or both, and you could probably cram the biggest stickest gumball tires you wanted under the car and have the room in your corrected power to weight to stay under the cap for TTU at 5.50:1

 

you've got to have a very close to stock Z06 to squeeze into TTA or TTS as I understand it

[Varkwso]

you're pretty solidly in TTU at 7.67 power:weight ratio with that car.

 

The good news is theres alot of room for more power, less weight, or both, and you could probably cram the biggest stickest gumball tires you wanted under the car and have the room in your corrected power to weight to stay under the cap for TTU at 5.50:1

 

you've got to have a very close to stock Z06 to squeeze into TTA or TTS as I understand it

 

Stock C5 ZO6 with 295 Hoosiers/Kumhos pretty much maxes out the TTA class. Anything else (like 315s) put you in TTS at a minimum. TTU puts you in the big boys...

 

jeff

[Cbntmn]

Well, i guess someones gotta finish last....lol

 

Is there an open passing class that is not TT that i can drive in to get used to the open passing? Like an advanced class?

[kbrew8991]

just come out in TT and drive the car, work on improving your own laptimes

 

you've got to have a HUGE bank account to win something like TTU nationally anyway, just come have fun

[Varkwso]

Well, i guess someones gotta finish last....lol

 

Is there an open passing class that is not TT that i can drive in to get used to the open passing? Like an advanced class?

 

Enter TT like Ken said - you can get used to getting passed! Tracquest/Chin allows open passing in some groups as does Seat-Time in the advanced group (point by anywhere).

[Cbntmn]

I run advanced group with seat.

You point me by all the time......lol

 

Have fun on the one lap.

[Cbntmn]

OK, so heres another question.

 

What would my HP have to be to go back to TTS? I may have the option of removing heads and cam and getting closer to stock HP

[kbrew8991]

you would need to be under 8.70:1 adjusted power:weight

 

that would let you run near stock power:weight ratio, but go crazier with suspension and tires than you could with TTA

[Cbntmn]

OK, as I understand it this is where i stand.

 

With this new car at 3150 pds ( i need to confirm the weight) and with my big tail in there at 250 pds the total weight would be 3400 pds

 

I get a .15 addition for the weight.

 

So in order to get to the 8.70:1 HP to weight ratio my HP can not be more than about 395.

 

3400/395=8.60 plus the modifier for weight of .15 = 8.75 and the TTS class. None of the other mods on the car really matter.

 

Is this correct?

 

If so I think I can remove some stuff to get to that HP rating. I would imagine "de tuning " the car for a little less HP would not be bad.

 

OR

 

I can ad balast and make the car heavier.

 

If I do that my car could stay at the 440rwhp and i would have to make the car 3700 pds with 440 rwhp. That would be 300 more than the weight im assuming the car is. maximum balast is 250 pds, so that would not work.

 

One other point is how the competition weight is arrived at. While my car is listed at 3118 curb weight, do i need to have it weighed along with the dyno sheet done? How is the gas taken into consideration with the weight calculation? or does the listed curb weight get used no matter what?

 

Damn, i just lost 30 pds. Dont tell me i have to gain it back to move my car down to a lower class!

[Greg G.]

OK, as I understand it this is where i stand.

 

With this new car at 3150 pds ( i need to confirm the weight) and with my big tail in there at 250 pds the total weight would be 3400 pds

 

I get a .15 addition for the weight.

 

So in order to get to the 8.70:1 HP to weight ratio my HP can not be more than about 395.

 

3400/395=8.60 plus the modifier for weight of .15 = 8.75 and the TTS class. None of the other mods on the car really matter.

 

Is this correct?

 

If so I think I can remove some stuff to get to that HP rating. I would imagine "de tuning " the car for a little less HP would not be bad.

 

OR

 

I can ad balast and make the car heavier.

 

If I do that my car could stay at the 440rwhp and i would have to make the car 3700 pds with 440 rwhp. That would be 300 more than the weight im assuming the car is. maximum balast is 250 pds, so that would not work.

 

One other point is how the competition weight is arrived at. While my car is listed at 3118 curb weight, do i need to have it weighed along with the dyno sheet done? How is the gas taken into consideration with the weight calculation? or does the listed curb weight get used no matter what?

 

Damn, i just lost 30 pds. Dont tell me i have to gain it back to move my car down to a lower class!

 

It sounds like you have got it, with the exception of the weight. We use minimum competition weight, which is the weight of the car with driver/helmet/safety gear at the end of any competition session. So, the amount of fuel in the car during weighing will be determined by you. If you are going to fill the tank full before every session, then it will have more, etc. The weight that we care about is the minimum weight that you and the car will ever be while competing. Curb weight has nothing to do with the classing of cars in TTS and TTU.

[Cbntmn]

So they weigh all the cars after each event? Or are they weighed once per year?

[Cbntmn]

Another question. Sorry guys, i just want to have this thing worked out before i attend an event.

 

If i have a 15 gallon tank, and its 3/4 full at the end of the session, then that would be 10 gals at about 8pds per gallon so that would ad 80 pds to my weight.

 

I guess it all depends on what the car weighs and what my gear weighs. Im hoping to pick up the new car on the next week. Ill have it weighed and see where I sit.

 

Right now Ive got to get the tuning straight to see if it can get down 45 or 50 hp. If that cant happen all the rest of this really doesnt matter because there is no way i can get the car heavy enough at 445 hp. Unless I start eating at Mcds and gain about 300 pds. Fitting in the race seat would be an issue at that point!

 

Thanks for everyones help. I really appreciate it.

[Greg G.]

We weigh the cars whenever we (Directors and tech inspectors) feel like it. A car can be weighed three times in one day, or once a year--the goal is to make sure that the cars are always legal.

 

Gas weighs about 6.5 lbs per gallon.

[Cbntmn]

So I really should not even worry about the gas weight and get the car right.

 

Just found out the car weighs right at 3020 pds. Its a little lighter than I expected. Also found out that MTI can detune the car by adjusting the timing and get it down to legal horsepower. So I just need to get my calculations correct and get the right HP to weight ratio and get legal no matter how much gas is in the tank.

 

Thanks for your Greg. Hopefully ill get to meet you at Roebling on Saturday.

[Greg G.]

 

Thanks for your Greg. Hopefully ill get to meet you at Roebling on Saturday.

 

That won't be happening, but hopefully you can meet Chris and Ken, your Regional TT Directors

[Cbntmn]

Ooops didnt notice your location Greg. Thanks for your help

[Varkwso]

I run advanced group with seat.

You point me by all the time......lol

 

Have fun on the one lap.

 

I am not sure tye gesture you are seeing is a point by