I bought my 1988 Rx-7 GTU in January and have been putting 89 octane in it as the previous owner did but since the motor is technically the the turbo motor I didn’t know if I should run premium like the turbo models because of the compression ratio or 87 in it like the N/A models because there’s not turbos? Anyone here know what fuel I should be putting in it?

 

if you can confirm that engine is an S4 NON turbo engine the specifications are below. The engine will not require anything above 87 octane as the manual states. If you can find NON ETHONAL fuel like recreation (boat fuel) will be one of the best options for the aging rubber fuel lines. My above statement is for a STOCK NON TURBO S4 engine.

Displacement: 1308cc/80ci

Compression Ratio: 9.4:1

Output(hp): 146bhp @ 6500 rpm

Torque: 138lb-ft @ 3500 rpm


-M

 

welcome to the board.
i'm not sure what you mean. unless the engine was swapped at some point, you should have the 6-port 13B in it. that said, even if you have a T2 engine in the car without a turbo attached, you would not need to run the higher octane because the compression would remain fixed.

if you have a turbo - whether the T2 block or the N/A block, then you should be running the high octane. does that make sense?