Unleaded Fuel, Did the 914/6 2.0 use Leaded Fuel? Options

[Jeffs9146]

As it says above, does the original 2.0 914/6 use leaded fuel or is unleaded ok? The book says 98 octain but it doesn't say anything about Leaded or Unleaded. My 74 had an Unleaded Only sticker but the 6 doesn't!

Jeff

[ArtechnikA]

My car has 11.5:1 Mahle pistons. When I'm on the track I run 110 race gas, but when I drive on the street I use premium with booster. So I'm not really gaining much by using the booster. Luckily I don't drive on the street very much.

yes, that's your static compression - but i bet you also have high-lift, high-overlap cams to take advantage of that compression at higher rpm. so considering all the charge leakage at lower revs, you actual dynamic compression could be pretty reasonable.

if octane booster is the difference between pinging and not, go for it - just one shouldn't be expecting miracles - and the sellers would like you to believe "4 points" means increasing from 92 to 96 but it doesn't. there's also diminishing returns, because higher-octane pump gas is more likely to already contain some of the chemical goodies in the booster stuff - and you don't get a linear percentage gain.

in olden tymes, we used to mix premium leaded and unleaded to take advantage of this effect -- adding just a little bit of tetraethyl lead to already premium unleaded raised its AKI a lot more than the same amount would increase the AKI of leaded gas.

i have also had to clean the orange manganese fouling from plugs after trying to run too much over-the-counter octane booster - wasn't worth it...