C4 hardtop = coupe?
Thread Starter
Burning Brakes
Joined: Feb 2000
Posts: 1,247
Likes: 2
From: Parker, Colorado, USofA
C4 hardtop = coupe?
According to NHRA rules, if a convertible breaks out of the 14's, it needs a rollbar.
The Sled should have No Problem doing that, but I don't want to butcher the car with a rollbar/cage. Being 6'6", an SCCA legal rollbar would make the convertible top inoperative, and/or make the car un liveable as a street car.
I've heard rumors that the C4 hardtop is a positive structural member, has undergone rollover testing and might classify the car as a coupe, bringing the performance envelope down to a 10.99 (which the car won't ever reach).
I cannot find anything to back up those rumors, can you guys help?
The Sled should have No Problem doing that, but I don't want to butcher the car with a rollbar/cage. Being 6'6", an SCCA legal rollbar would make the convertible top inoperative, and/or make the car un liveable as a street car.
I've heard rumors that the C4 hardtop is a positive structural member, has undergone rollover testing and might classify the car as a coupe, bringing the performance envelope down to a 10.99 (which the car won't ever reach).
I cannot find anything to back up those rumors, can you guys help?
Race Director
Joined: Oct 2001
Posts: 19,653
Likes: 428
From: Melbourne Florida
Cruise-In IV Veteran
Re: C4 hardtop = coupe? (RocketSled)
I had a question about drive shaft loops for an IHRA track...I went to their website, found the head of tech and emailed him..got a reply, printed it and put it in my glovebox..try this with the NHRA website...worth a shot...good luck
Race Director
Joined: Feb 2003
Posts: 18,484
Likes: 1
From: Everyday you must choose between the pain of discipline and the pain of regret. Fredericktown, OH
Re: C4 hardtop = coupe? (RocketSled)
I am not sure about the hard top quesiton - but I am almost 100% certain that the NHRA requires a 5-point (most people just do 6) for ANY car that runs 11.99 or quicker. IHRA I beleive requires the same bar at 11.50.
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Re: C4 hardtop = coupe? (golfboy1)
I had a question about drive shaft loops for an IHRA track...I went to their website, found the head of tech and emailed him..got a reply, printed it and put it in my glovebox..try this with the NHRA website...worth a shot...good luck
Thread Starter
Burning Brakes
Joined: Feb 2000
Posts: 1,247
Likes: 2
From: Parker, Colorado, USofA
Re: C4 hardtop = coupe? (scorp508)
What did he say if you don't mind me asking. That c-beam has always looked like it would contain any driveshaft explosion to me.
My car, at altitude will probably turn mid 13's. Fast enough to be a problem with the ragtop, helmet, and driveline loop, but I don't think it'd need the 5 pt harness yet.
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Thread Starter
Burning Brakes
Joined: Feb 2000
Posts: 1,247
Likes: 2
From: Parker, Colorado, USofA
Re: C4 hardtop = coupe? (RocketSled)
W00t! From the NHRA:
Six bolts in back and two up front seem pretty permanent to me!
Mike,
if you permanently attach the hard top to the car. it will no longer be considered a convertible. the top can not be easily removed to be considered a coupe. then if it runs 11.99 to 10.00 it will require a rollbar. Thanks Rick
if you permanently attach the hard top to the car. it will no longer be considered a convertible. the top can not be easily removed to be considered a coupe. then if it runs 11.99 to 10.00 it will require a rollbar. Thanks Rick
Elite Torch Red Member
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From: Exit 89 GSP,Lakewood,NJ The Land Of Mojo
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Re: C4 hardtop = coupe? (RocketSled)
We go thru this all the time. Due to the success of our Corvette Challenge series, an awful lot of hardtops have been sold in NJ(or rather to NJ members).
The hardtop will let you get to 12.00 without the need for a rollbar.
The hardtop will let you get to 12.00 without the need for a rollbar.
