Project: 50,000 mile 1983 RX-7

Posted by Matthew Schroeder on

We've been entrusted to work on a first time customer's 49k mile 1983 RX-7. I have a soft spot for the FB RX-7. I've had five since I was in High School. This clean example may rival my current and best!

                           I'm a little jealous of the zinc plating!


Opening the hood was like opening a time-capsule. I believe that everything but the spark plugs was original. I feel a little better knowing that we can still get a lot of original manufacture tune up parts for these. This one came in because it lacked power at high rpm. We like to use a little modern technology to work on old cars but are mindful of making modifications in doing so.

A wide-band oxygen sensor port will be hidden under the factory heat-shield.


Watching fuel bowel levels while on the dyno revealed a fuel volume problem that was corrected with a simple filter change. From there, we had poor choke operation, a stumble off of idle, jerkiness at cruise, and it felt a little weak on the big end. Not wanting to spoil the stock appearance of the car, an o2 sensor connection was placed where it would be hidden by a heat shield. With this, I was able to see what was really going on. Idle was lean, cruise was lean, and it was way over rich wide open. Adjustments to the choke's throttle linkage, re-sizing the pilot and primary main jets, and cleaning foreign matter from emulsion tubes made the mixtures correct and the power smooth.

                     Smoothness and a few horsepower as a bonus


Performance isn't always about getting the most power from an engine -- particularly on vintage cars. No extraordinary efforts were made to extract more power from this car, but 107.8 silky smooth rwhp isn't bad for a 100% stock car. Got a special old rotary that you think could run better? Contact Us to find out what we can do for your rotary.


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