Class
Letter |
Class |
Common Engine |
Relative
Speed* |
Minimum
Driver Age |
Maximum
Per Heat |
Minimum
Length and Other Information |
Minimum
Weight With Driver |
Y
|
1.0 Liter Modified |
Yamaha, Polaris |
105 MPH |
16
|
12
|
14’6” Min. Length |
825
lbs |
17’6” Max. length |
9’6” Max. Width |
T
|
1.5 Liter Stock |
Toyota |
95 MPH |
14
|
12
|
14’6” Min. Length |
825
lbs |
17’6”
Max. Length |
9’6”
Max. Width |
S |
2.5 Liter Stock |
Ford |
100 MPH |
16 |
12 |
13’6” Min. Length |
1025
lbs |
17’6”
Max. Length |
9’6”
Max. Width |
A
|
2.5 Liter Modified |
BMW, Ford Chevy, Esslinger |
125 MPH |
16
|
10
|
17’6” Min. Length |
1225 lbs (146 CID gas or 155 CID)
1325 lbs (146 CID or 166 CID) |
9’6”
Max. Width |
E |
5.0 Liter Stock |
Chevy |
115 MPH |
16 |
10 |
16’ Min. Length |
1450 lbs |
21’
Max. Length |
11’
Max. Width |
NM
|
National Modified
(6.0 Liter Modified) |
Chevy |
140 MPH |
16
|
8
|
17’6” Min. Length (166 CID or less) |
1225 lbs (146 CID gas or 155 CID)
1325 lbs (146 CID or 166 CID) |
9’6”
Max. Width (166 CID or less) |
17’ Min. Length (246 CID) |
1350 lbs (246 CID) |
19’ Min. Length (308 CID or 368 CID) |
1900 lbs (308 CID or 368 CID) |
18’ Min. Length (built prior to 10/30/87) |
1600 lbs (built prior to 10/30/87) |
GNH |
Grand National Hydro
(7.0 Liter Stock) |
Chevy |
150 MPH |
21 |
8 |
20’ Min. Length |
2200 lbs |
2000 lbs (built prior to 11/1/97) |
20’ Min. Length (511 CID) |
2500 lbs without driver (511 CID) |
26' Max. length (511 CID) |
GP |
Grand Prix |
Chevy |
160 MPH |
18 |
8 |
26’ Min. Length |
2700 lbs |