I have a 1984 Volvo 240 with the Finnish/Danish B19K motor. This type runs on 98 octane leaded fuel, which is getting more and more scarce.

I'd like to adjust the ignition, so the motor will run on 95 octane unleaded. We have an adjustment set, but need the figures for the exact level of adjustment.

With 98 octane leaded fuel,the ignition is set to:
7 degrees before top at 700-800 RPMs.
17-23 degrees before top at 2500 RPMs.

What would be the figures be for 95 octane unleaded?

Also, are there any other considerations to bear in mind when making this adjustment?

Advance thanks

I don't have any written info. I do have an older Volvo with the 10 to 1 compression and it runs fine on the 93 octance here in the US. I backed off the
timing about 2 degrees to be sure. I would think the car would be fine with stock adjustments of the timing. The main change I had to make was to adjust the mixture because here in the US the unleaded actually makes the motor run a bit
leaner so I had to richen the mixture a bit. What type of ignition system is
on your car? The Chrysler ignition has a knock sensor. That will protect the motor from damaging ping. Hope this helps you.

Dave 82 242ti 273k mi.