we can get only 91 and 95 octane fuel, nothing less. its the same price! in the future they are planning to sell only the 95 in austria. should i do a timing adjustment to go with 95 or is it fine like it is?

chris
454 mag

I have a feeling your motor won't know the difference.


Darrell.

Chris,,,in europe the fuel octane is mess. diffrent.
A 91 european octane fuel is actually about 98 US octane !!!!!

So u be more then fine actually maybe better off.
I lived in germany all my life and had race engines that needet 110 octane fuel in the us and in germany i fueled the 95 or 98 shell super and they where fine .
Thats how i know because i had done that research in late 90's.

wow, thats intresting. so, would you recommend me to go with 91 or 95. as i mentioned - the same price. i always thought: the more octane, the better, but lower octane also has its advantages. and maybe this summer there will be only 95 available. adjusting the ignition point could be necessary. am i wrong?

First thing is to find out how your octane measurement compares to US octane ratings.

I would go with 91 in europe !!!


But may wanna check with MARCO HANISCH in Mainz Germany . Don't have his # anymore but he knows all that stuff for shure. Thats who told me and it worked.

ok, that fine, will call him

Hanisch GmbH
Reichelsheimer Str. 10
55268 Nieder-Olm

hope this is correct

Do you know what the compression ratio is on your engines? If it is low to medium, use the 91 octane. If you have a 12.5:1 or blowers, use the high octane.

I bet you do not have high compression with a stock 454 mag. 91 octane in the US is plenty for that motor.

yes, i know that 91 is enough, but i cant get that stuff!!! what happenz when i use 95? i think there is no problem wih it, but maybe i should think about adjusting something to the much higher octane than recommend.

I agree, do this first.

Running higher octane than required won't hurt your engine, it just might lose a little power (very little). Higher octane fuel burns a bit slower, and with a low compression engine you might not get a full burn on the power stroke. Advancing the timing can help if you run into that situation, but personally I wouldn't mess with it.