1987 · TECHNICAL
1987 Technical Regulations
1987 introduced a 4.0-bar maximum turbo boost limit enforced by a pop-off valve, along with the reintroduction of a 3.5-litre atmospheric engine class as a parallel category. Turbo cars kept the 195-litre race fuel limit; atmospheric entries had no fuel cap. The reintroduction was a transitional step toward 1989's total turbo ban. Two parallel championships ran during 1987 and 1988: the main World Championship (still mostly turbo) and the Jim Clark Trophy for atmospheric drivers + Colin Chapman Cup for atmospheric constructors.
4-bar turbo boost limit
A standardised pop-off valve limited turbo boost to 4.0 bar absolute. Exceeding the limit triggered venting, so peak qualifying boost fell significantly. This pulled qualifying power-output back below 1,000 bhp for the first time in several seasons. The pop-off valve was itself a piece of equipment teams obsessed over; small mass and spring tolerances at the edge of the rule produced measurable advantages.
Key changes
- 4.0-bar turbo boost limit enforced by standardised pop-off valve.
Atmospheric 3.5L class reintroduced
A parallel 3.5-litre normally-aspirated engine class returned after four years of turbo-only. Teams running atmospheric were largely smaller operations (Tyrrell-Cosworth, AGS, Larrousse). They competed for the Jim Clark Trophy (drivers) and Colin Chapman Cup (constructors) in 1987-88 as preparation for the mandated atmospheric-only grid in 1989.
Last updated: 2026-04-24
This summary is editorial material prepared by F1pedia for general F1 audiences. It is not a legal reference. For binding rule text, consult the official FIA document.