Mazda SA Rx7 classic cars | These Mazdas are becoming more fun to drive,

...not that they have become better cars, it is because they have something that the newer ones cannot do. Driving this car offers up an Analog experience / feel, it is that which has been engineered out of the cars of today.

It was bound to happen as technology gave us a version of 'better' that we supposedly wanted. Which for me, I fully understand, I want to get in my daily driver and have those amenities that make for a tertiary good experience on my way to work or wherever.

The Mazda Rx7 loves to be driven hard and often | 12A Rebuilds

That is where a dedicated real driving experience is one to be appreciated at the right time. Analog driving means that I feel everything the car is telling me. For a spirited experience, that seat of the pants feel is what it is all about. If you are reading this, I believe you know exactly what I am talking about.

The reasons for this trip to REspeed is to replace the corroded exhaust with one that doesn't pop & bang on deceleration as air is passing into the exhaust pipe via the air pump as the cast iron walls have cracked and collapsed. There is no replacement other than the racing beat exhaust upgrade.

The car that came in to our shop has been here a few times over the years, it is a drivers car. Originally bought new, this has been in their family for 45 years, all original. The 12A has proven itself to be a tough motor.

What makes this motor so tough, first the amount of power it came with is minimal to what we can get out of it. For 1.1 liters (1146cc), what does very well is being driven and driven hard. While the Rx7 first gen is the first of the line, the 12A goes back to 1969 with several important upgrades along the way. I have seen more of the chassis & wiring degrade enough to not be worth saving over the 12A motor. They break and sit for long periods of time rotting away in the process.

At this time, the engine requires a rebuild.

This time though turned to be actually good for the car as a whole, the motor started leaking coolant out the rear through bolts (via the rubber infused washers). The car got dropped off, and the next morning we started it up, brought it in and put it on the lift, started to remove the exhaust system and closed for the night. Fast forward, the next morning and there was a large puddle of coolant on the floor in the morning coming from the rear of the motor. Look closely and you'll see antifreeze (fresh antifreeze) on the rear housing. 

This leaking is an indication that the seals are all drying out. Replacing them (rebuilding the motor) is a lot more cost effective then waiting for it to eat up the seals, dry out the system and overheat the motor tearing up rotor housings, rotors and destroying itself while rotating into a lump of non useable parts.

These 12A motors are tough, they can handle a lot of being driven hard, they must be driven though, sitting around is not good (especially in our hot, dry climate). If you wait for the right time to rebuild it, your schedule may not be in sync with the actual time left on the motor. The thing that is true about most engines is true with the rotary engine, do the maintenance, drive it like it should be driven and the longevity is there, pay attention to the details.

Part 2 we will show internals, what went wrong, the new engine and components along with some solid upgrades for high altitude performance.