Results

Reassembly was straight forward. The engine started after I put it back together. Re-alignment of the crank pulley gave me the correct valve timing again. The car's performance improved. Prior to the repair, my carwould take 15-16 seconds to accellerate from 50 to 70 mph in 5th gear. After the repair, the typical times were 12-13 seconds. which compares well with the 13.8 seconds reported by Car & Driver in their initial test report on the 1990 miata.

I did the work in November of 2000. I got 3 years and close to 25K miles on the repair. The car is a daily driver and used for autocross. I have heard from two other owners who have more than 25K miles on their repairs.

B. Final

In the Spring of 2004, the car felt slow again. I inspected it and found that the crankshaft bolt had come loose. When I opened up the engine, I found that the front crank seal had leaked. Knowing that oil attacks Loctite compunds, this could be one reason why it came apart. For that reason, it's probably a good idea and only a little more work to change the front crankshaft seal when doeing this repair.