I AM keen to buy a Porsche 944 and have been doing research on the model variants. Ideally I would like a 1989-1991 S2, not turbo. Two things pushing me towards this choice are that it's the latest model variant, and 1987 and later models were built for unleaded petrol. However, there are few available and prices are often well above my budget of $17,000. Will 1986 and earlier models run on unleaded fuel, with or without additives?
THEY'LL happily run on unleaded without an additive. The valve seats are the same in the pre-'86 engines as those built after the introduction of unleaded fuel. But you will need to run 98-octane fuel if you want to get the best out of it.