Does anyone recommend a certain octane rating gas for the classic minis? It's for a 1974 Austin Cooper with original 1275cc engine if that helps. Thanks alot. ^_^

 

I put regular unleaded in mine. You might have to use a lead additive in the gas on your engine. I haven't had any problems with mine without it though. You can buy the lead additive at parts stores. I've found it at advance auto parts.

 

93 Octane. Anything lower will make my engine cough when I shut it off. No lead.

 

The previous owner of my pickup used 98 octane plus a booster, but it was pretty heavily hopped up. I used the highest octane I could find with an octane boost and it ran fine.

 

I tried mid grade in mine once....kick, spit, sputter, backfire

never tried that again

{1275 Metro, HIF-6 with K&N, LCB, PlayMini twin DTM}

heed the advice here about leaded gas.. from Haynes:

"Models built up to October 1988 (as delivered from the factory) cannot use unleaded petrol; the valve seats fitted as standard will suffer serious premature wear...."

You want to verify that the head has been modified or swapped.

Recommended fuel (per Haynes and cross checked to owner's manual on Heritage CD), other than the lead warning is 95 measured by the RON method for all engines...(different than what we use in US, but generally equates to US 'high test' or premium.) But this assumes a factory setup .... different carb needle and futzing with the timing a bit and the engine can be happy on less. You'll get less power but it can run smooth.....

 

So I should be running premium in mine?

 

Thanks alot guys. Lol didn't know either bumble?

 

The book simply says the octane rate it says...aka "hi test"

don't matter what engine

factory spec is what it is.... "hi test"


If ur engine runs good on less, it has been detuned to do so....but if u r happy, wat's a matter?

My 75 Cutlass, 350 and 4 barrel called for hi octane. As the gas companies backed off on what they made and I wanted less PING, I retarded the timing....it works up to a point....it got almost 12 mpg