I just got my hands on an 88 740 turbo wagon as a winter car for my summer car. I love the car, really smooth runs good.
was wondering if i need a better grade of gas because of the turbo or if the 87 will do. I dont hear any pinging with the 87 i filled it with a few days ago. just want to make sure i am not slowly killing the car.

I am new to this Volvo world so any insight would be great.

thanks.

 

If you really want to help the car (short-term and long-run), try using 89 or even 91. 89 would be preferable (turbo) and 91 can be used occasionally. You may even notice a difference in the 'driving experience' or mileage per gallon.

 

if you ask me, unless you have modified your car the better octaine gas in not really going to do a whole lot. I looked at my S40 and found that the computer has been tuned to pretty much accept any gas you can find. Now that I have it chipped I have to run 91 or better as the timing and everything has changed. The only thing the higher octaine might do for you is get rid of some of the knock, if you have knock.

 

The car was optimized for premium (in the US, 91 octane). It won't knock on regular (87) BUT your gas mileage will go down a bit. Running regular will NOT hurt the engine.

A knock sensor is used to retard the timing on both the Bosch and Regina FI systems.

My normally aspirated 940 runs fine on regular, but I CAN feel the difference in lost power. And I lose at least one MPG...