Started 1981 and ended after the 1989 season.
Millions of spectators around the world and sometimes up to 500,000 people watching from the shore.
Many major sponsors and here is a list of some..
Cool, Aspen, Carlsberg, JPS, Benson&Hedges, Martini, Castrol, Nordica, Nashua, Denim, Champion, Trimite, Peter Stuyvesant, Gordon’s Gin, Tecnocar, Beneteau, Dole, ITC, Lasse Strom Marin, Naiu, ToTip, Stefanel and many more.

The eighties was by far the most interesting time in tunnel boat racing.

Bob Spalding in the #11 Velden Racing/JPS/Johnson V8 from 1981/82.
Probably to most famous motorsports sponsor ever.

Lots of money..

March 5 1975 was the day when one of my biggest dreams come true.
This letter from OMC Racing and Jack Leek made this little Swede tear up.

Renato Molinari driving the #2 OZ Class Molinari/Saffa/Evinrude CCC V6 2.448 crossflow in London/Thames 1977.

Renato Molinari driving the #2 OZ Class Molinari/Saffa/Evinrude CCC V6 2.448 crossflow in Bristol 1977.

Jimbo McConnell driving the #26 OZ Class Molinari/Saffa/Evinrude CCC V6 2.448 crossflow in London/Thames 1977.

Bob Hering driving the #3 OZ Class Molinari/Saffa/Johnson RS V6 2.448 crossflow in London/Thames 1977.

Evinrude advertising after Renato’s success in Bristol 1977.

Renato Molinari and his black #18/Molinari/Evinrude F1-V8. My guess is this is from a special race event in Italy 1984
Thanks you Antonio Collini for the pictures.

Pretty interesting comment from Roberto Bigi about the three pictures above.  Here is a picture  from Clear Lake outside Houston, Texas 1983 when Renato raced the Unlimited Hydroplane class with 2 X Evinrude F1-V8 engines.

Roberto Bigi The black boat used at Como lake by Molinari was exactly the same boat used in Houston with 2 engines for the Unlimited world championship.

Here is why I am pretty sure this is the twin F1-V8 boat Renato raced in the Unlimited Hydroplane race at Clear Lake outside Houston 1983.

1. You can clearly see how wide the boat is in the rear under the rear boat cowling. This is done to get a wide transom to fit two engines. The second picture show a regular single engine Molinari boat from same year.

2. The single engine installation on a twin engine transmission forced Renato to make new much wider steering bars.
The second picture show standard OMC F1-V8 steering bars from same model year.