thanks Keshav.Hi Michael,
In a nutshell, Alpina is to BMW what AMG is to MB. Top class tuners whose cars cost more than the the originals. And some of them cost many times that of an original, from Alpina to BMW. Alpina’s speciality till today is the drivetrain Upgrades which make their cars way more powerful than the original BMW cars.
Here are a couple of well known pics of a world class Alpina E9. The differences to the drivetrain are significant.
View attachment 82711View attachment 82712View attachment 82713View attachment 82714
I think that the Procar statement could be misconstrued. The bulk of the upper M1 is a tube frame, and the procar had bolt-in crossbars, such as the door bars and the X brace above the motor. The stock M1 was still essentially a welded cage. Also, the bolt in pieces are connected to welded tabs. The bolt in cage above is a slip fit cage, like a bolt-together trampoline (but hopefully stronger). I admittedly don’t know how strong they are, and what the rules are on bolt-in cages. Personal bias, I generally view it as an after thought on a car that is purpose built for racing. I’m only an internet racer however.There is nothing wrong with a properly designed roll cage which is bolt in. Even the M1 Procar came from the factory with a bolt in cage. It is important that it is attached properly, not just thru the sheet metal.
Very cool. Thanks for clarifying Markus! I’m guessing they tried aluminum first since the M1 was considered a little heavy. I’m at the peak of my M1 knowledge, which is almost nothing.The above picture shows just the steel frame which is supporting the fiberglass panels. In addition to this there is a complete roll cage. Originally the cage was made out of aluminum but IMSA made us change the cage to a steel version in 1983 as the aluminum was not deemed strong enough.