95 or 98 octane petrol for 348?

Man, I wish I had that kind of choice. There is nothing over 93 around here.

Any increase in power or performance would be marginal relative to the extra cost of of the higher octane.
The only real gains of higher octane would be realized in older engines without computerized knock controls and higher compression engines with increased timing advance (more knock control), otherwise it's wasted money more or less.

I can buy 110 octane leaded here in town but it really doesn't do much to increase performance. It does smell good coming out the exhaust though.

 

Spasso - the UK 95 / 98 corresponds to our 91 / 93 octane. We use a different octane measurement scheme here in the US.

 

The only real gains of higher octane would be realized in older engines without computerized knock controls and higher compression engines with increased timing advance (more knock control),


Which models normally have computerized knock control and/or higher compression engines with increased timing advance?

 

Computerization started with 308GTB/Si. I donk know how sophisticated it was, but I was told that the computer had several different advance curves.

Re noncomputer cars, my 2 '72s do fine on 91 octane

 

The correct answer, right there.

 

Thanks for the clarification.

 

My statement was directed to engine types in general. Not Ferrari specific.
A 1970 Chev 327 small block is an example of an engine with no knock sensor.
A 1970 Chev 327 small block with 13:1 compression and a 671 blower would be an example of a high compression engine with increased advance.
Anti-knock was controlled by the high octane and lead additives of the old days.
Just about everything in 80's had some sort of knock sensor/control, most of which were very rudimentary and not necessarily controlled by computer.

In the 90's is when it was refined to a much higher level and worked in conjunction with engine management.

 

In my 1989 Mondial t Cab 3.4 (same engine as 348) and Metronic (sp?) 2.5, I use the highest octane fuel I can fine.

However, when traveling, I have been to stations where Regular was 85 octane and the highest octane was 89.

Will using a tank of this at highway speeds (but not high performance driving), hurt the engine or are the electronics smart enough to correct for it?

Also, many stations are now using up to 10 % alcohol. Will this hurt the Ferrari engines especially the rubber parts? If that fuel is burned off on the same day, is there likely to be any long term issues?

Thanks.

 

You should be able to get away with running 89 octane once in a while without any serious consequences. The electronics can compensate for it mostly but in some cars maybe not 100%.

My BMW's require 93 or higher octane but they will run quite well on 87 anyway. It is NOT recommended to do this in the owner's manual so I don't, except in emergencies.

I also pay the few extra pennies more for high market gasoline like Chevron versus gas from economy stations. The needed additives and cleaners are only about half in economy gas hence the lower price.

As far as I know there shouldn't be an issue with running 10% ethanol in the '80's cars and newer. Older carbureted cars have been known to suffer from it but I didn't seem to have a problem with the numerous 240Z's that I owned. Higher concentrations are a different story.