| Teams 1971 Islip 250 |
|---|
| No. | Team | Driver | Mfg |
|---|---|---|---|
| 4 | John Sears | John Sears | Dodge |
| 6 | Castle Racing | Frog Fagan | Dodge |
| 6 | Castle Racing | Neil Castles | Dodge |
| 8 | Negre Racing | Ed Negre | Ford |
| 10 | Champion Racing | Bill Champion | Ford |
| 12 | Holman-Moody Racing | Bobby Allison | Mercury |
| 19 | Henley Gray Racing | Henley Gray | Ford |
| 23 | Robertson Racing | Jabe Thomas | Plymouth |
| 24 | Gordon Racing | Cecil Gordon | Mercury |
| 25 | Robertson Racing | James Cox | Plymouth |
| 28 | Brooks Racing | Bill Hollar | Ford |
| 30 | Vic Ballard | Walter Ballard | Ford |
| 34 | Scott Racing | Wendell Scott | Ford |
| 39 | Friday Hassler | Friday Hassler | Chevrolet |
| 40 | US Racing | D.K. Ulrich | Ford |
| 41 | Ken Meisenhelder | Ken Meisenhelder | Chevrolet |
| 43 | Petty Enterprises | Richard Petty | Plymouth |
| 45 | Siefert Racing | Bill Seifert | Ford |
| 48 | Hylton Engineering | James Hylton | Ford |
| 49 | GC Spencer Racing | G.C. Spencer | Plymouth |
| 62 | K-Automotive Performance | Bennis Listman | Dodge |
| 64 | Langley Racing | Dick May | Mercury |
| 67 | Ron Ronacher | Elmo Langley | Mercury |
| 68 | Allan Schlauer | Larry Baumel | Ford |
| 70 | McDuffie Racing | J.D. McDuffie | Mercury |
| 73 | Churchill Motorsports | Jerry Churchill | Ford |
| 74 | Shirey Racing | Bill Shirey | Plymouth |
| 77 | Roberts Racing | Charlie Roberts | Ford |
| 79 | Warren Racing | Frank Warren | Dodge |
| 86 | Castle Racing | Bobby Mausgrover | Dodge |
| 89 | Wiltshire Racing | George Wiltshire | Plymouth |
| 91 | Junior Fields | Pete Hamilton | Chevrolet |
| 96 | Garn Racing | Richard Childress | Chevrolet |