5 replies to this topic

[ep90]

Does anyone know which year Mini's went from leaded to unleaded fuel?

[Bungle]

my cooper is a 1990 and one of the first i think :wink:

[ep90]

Thanks

[minidaves]

1989 half way through f reg

dave

[Guess-Works.com]

First unleaded engine in a mini was 99HD81 anything before that is leaded, anything after unleaded.

See A series engine numbers FAQ

[Dan]

There wasn't actually a date when they changed. There was of course a date when unleaded became standardised and if your car was made after that then it will definitely be unleaded but before this date there was an optional green pack available which confuses things a little. This included an unleaded head, unleaded size fuel filler neck, different plugs and there was also an optional carb type catalyst (an awful power sapping thing which didn't work to well anyway). Oh yes, and a little square sticker on the slam panel marked 95ron in green and Pb with a cross through it.

And of course any Mini made for the Japanese market ever will have an unleaded head as Japan has never used tetra-ethyl-lead as a fuel additive (which is why all the research into whether or not you needed to convert classic cars when 4 star became unavailable was pointless. The manufacturers did all that research years ago for the Japan market and found that you definitely always need valve inserts in cast iron heads).

I don't suppose you have a Japanese Mini though? But you might have a green pack Mini as they were quite popular. Unleaded was a lot cheaper than 4 star back in '88 and there was a VAT incentive to go unleaded so this pack sold quite well I believe.