about to get my new(to me) 66 classic s running
1275- what grade of gas should i run?
doug

 

Is there a sticker on the gas filler area that shows which octane to use?

The new MINI has a sticker that says use 91 octane or better premium fuel only.

If you do not have a sticker then you can try unleaded plus or unleaded regular and see how your car runs. check for pinging from the engine on slight upgrades.

If you fill with premium gas you will do no harm.

I would try unleaded plus and see how things work for you.

 

I tried a tank of mid grade once ... I had run-on and bad knock like crazy

never tried that again

I have a 1275 modified for unleaded, 1 1 3/4 HIF w/K&N cone filter, and LCB to PlayMini twin DTM. The plugs are clean everytime I pull 'em.

Runs great as long as it is 92 octane or better....

 

mine box stock, compresson 9-1. now if i have to run high octane
that makes 2 04"s & 1 66;s on the high teck. stuff.
pays the rent @ the local gas station
doug

 

Ask the previous owner if the exhaust valve seats have been replaced with ones for unleaded gas. (harder)

 

Premium. Most will knock & run-on w/o it. Besides, it only costs $15 to fill it...

 

Run the least amount of octane in your gas as posible with out your car pinging. Octane is a fuel stablizer that makes your gas so that it does not predetente (which causes the pinging) As your engine gets hot the fuel will predetente before you are ready for the explosen. If that happens than the fuel is pushing down on the piston before it hits "top dead center" (The top of the stroke) resulting in the pinging noise you hear and loss of HP because your engine is working agenst itself. If you have too much Octane than you are losing HP because your fuel will burn to slow inside of your cilinder and you will not have sharp explosion.


So basicly you want to run just enough Octane for your engine to run with out pinging, so you get the most HP out of your engine as you can without hurting it

Hope that helped and I did not bore you to much

 

thanks all , did not bore me:just have to learn how to bring this car back to life & not screw it up. have had austin heales (spell) &spitfires a long time ago,just a foggy memorie.
doug

 

When I bought my Mini,I was told that 93 octane is the lowest grade available in England,so I won't use less than that unless it is an emergency. I actually put in 1/2 a gallon once to get me to a station with premium.

 

My suggestion

for the most part we are running 60 and 70 era engines. Shouldn't we assume they were built for the octane common in the day?

I suggest, at initial start up, run the highest you can get, short of race fuel. You can always try to back down later.

I've had one car that really didn't like higher octane gas .... my 95 Miata actually runs poor on anything above 89....but I think that's pretty unusual

 

spent most of the day with a magnet going over the car looking for bondo&patch jobs.car looks ok might have lucked out. have become best friends with mini maina & 7.new master cyl. for break &clutch on the way.
also fuel punp ele. if you guys &gal can bear with me i"ll have a lot of questions along the way to this long term job. maybe we can all learn as this project proceeds. always looking for hints, thanks, doug