Installing The Engine #902The engine on John Thornton's race car is a high performance, short life 1600cc 912 engine characterized by 12.5:1 compression, light weight components, double valve springs and a special exhaust. Every 25 to 50 hours of use requires that the engine be 'freshened'. This is a pure race car. It is not licensed for the road nor would it be fun to drive there. It is too stiffly sprung, too hard to get into and out of and too noisy. But what it does, it does very well. I hang around John and his car regularly. Other coverage can be seen here:
And more coverage of CSRG races, the group with which he races.
After the engine refresh was finished, I took my motorcycle jack to the car and John and I put the engine back into the race car. It was a chance to see the engine with much of the sheet metal removed so you can see what's inside.