Welcome to the IMSA History unofficial website

This site is aimed at bringing you memories from the glory days of sportscar racing in the US.



The very first race, held at Daytona, would feature Grand National cars alongside the usual GTs. Peter Gregg, Brian Redman and John Fitzpatrick took the win in a BMW 3.0CSL entered by Peter Gregg Racing. Al Holbert and Claude Ballot Léna were second in a Porsche Carrera RSR. Jim Busby and Hurley Haywood took third place in another Porsche Carrera RSR. Bob Hindson, Frank Carney and Dick Davenport won the GTU class in a Porsche 911, Charles Mendez, Dave Cowart and Dave Panaccione finished second.

At Sebring, Al Holbert and Michael Keyser won the race in a Porsche Carrera RSR, but they were both waiting for their new racer in the name of the Chevrolet Monza. John Gunn and Carson Baird finished second and Roberto Quintanilla-Roberto Gonzalez were third. The top six finishers were Porsche Carrera RSRs. David McClain and Dave White captured the GTU win, Charles Mendez and Dave Cowart were second.

Road Atlanta would be a landmark, with eight Chevrolet Monzas taking the green! Al Holbert and Michael Keyser were 1-2 with Peter Gregg coming in third in the BMW 3.0CSL. Brad Frisselle was back in winning form, taking the GTU class in his Datsun 260Z. Dave White and Rusty Bond were next.

At Laguna Seca, it was Al Holbert again, followed by Peter Gregg and Michael Keyser. Walt Maas was outstanding in GTU, beating Brad Frisselle's Datsun 260Z in his Porsche 914/6.

At Ontario, Jim Busby put up a great race to beat Peter Gregg and George Dyer. Dennis Aase won the GTU class in his Porsche 911 ahead of Walt Maas and Jim Cook, both driving very competitive Porsche 914/6s.

At Lime Rock, George Dyer took his first ever victory at the wheel of his Porsche Carrera RSR. Michael Keyser and Jim Busby were right behind him. Brad Frisselle would beat Walt Maas in GTU.

Mid Ohio saw a great fight between Al Holbert and Michael Keyser. The latter won over the former and Jim Busby was a convincing third in his Porsche Carrera RSR. Brad Frisselle again took the GTU win, beating Walt Maas.

The Paul Revere race was won by Al Holbert, followed by George Dyer and Peter Gregg in his BMW 3.0CSL. Brad Frisselle won the GTU class with Rusty Bond and Ren Tilton in the second spot in a Porsche 911.

Sears Point was a hot place, and Jim Busby took another win over George Dyer, both driving a Porsche Carrera RSR. Peter Gregg was third. Walt Maas was at home and grabbed the GTU win over Brad Frisselle in his Datsun 240Z and Dennis Aase in a Porsche 911.

Talladega was won by Peter Gregg, who was ahead of Phil Currin, in a Chevrolet Corvette and Bob Christiansen in a Chevrolet Camaro. Brad Frisselle was back to business with a new win over Dave White and Rusty Bond.

Pocono was the place where Al Holbert could not lose, and he won over Peter Gregg and Elliot Forbes Robinson in the Bob Sharp Datsun 260Z, who beat Brad Frisselle in a similar car for the GTU win.

Jim Busby ran solo and won the 6 Hours of Mid Ohio, ahead of Peter Gregg and Hurley Haywood in the BMW 3.0CSL. Al Holbert finished third in his Chevrolet Monza. Brad Frisselle and John Morton dominated the GTU class and were well ahead of Bob Speakman in another Datsun 240Z.

At Road Atlanta, Al Holbert took another victory over Jim Busby in his Porsche Carrera RSR, and Michael Keyser and Jim Trueman in the Autosense Chevrolet Monza. John Morton and Brad Frisselle won again the GTU class over Dave White and David McClain in a Porsche 911.

Jim Busby had another great run in his Porsche Carrera RSR, beating Peter Gregg in his BMW 3.0CSL and Hurley Haywood, who drove the GW Dickinson Porsche 934. Walt Maas won the GTU class in his Porsche 914/6, followed by Jim Cook in another Porsche 914/6 and Jim Borsos in a Porsche 911.

The Daytona Finale was won by Michael Keyser in his Chevrolet Monza, but it was Charlie Kemp who took a very exciting second place in his Ford Cobra II. Danny Ongais was third in a new Porsche 934, which was now eligible in GTO. Brad Frisselle and Elliot Forbes Robinson finished 1-2 in their Datsun 240Z, with Bob Hindson taking third place in his Porsche 911.