Hey guys, a friend of mine has an 89 760 Trubo sedan and he doesnt put premium fuel in it, he says he never has (he got it used). Is this bad, i have a 740 turbo and have always ran premium (dealer said to) or else it misfires a little when pushing.

 

Different areas of the country have varying quality of octanes. My 2.9l recommends premium, but a good brand of 87 runs fine for in city driving. I usually put some 92+ octane in it every other tankful.

If you don't have knock under pressure and the performance does not seem hindered, then it is OK. Worst part is the plugs will probably foul prematurely, but they are cheap to replace considering the cost per gallon of premium fuel now.

 

Volvo always recommends high octane gas for their cars.

I use regular gas in my car because premium is just way to exspensive.

However for awhile I did use the middle grade gas and gas mileage improved and the car felt smoother.

But it isn't bad to not use premium.

 

An S80 owner here in New Zealand drives using 98 octane petrol. He recons that he gets over 800k's per tank around town. Says that you don't see too much difference while driving. But he says that it starts better and he has heaps of power from the turbo when he wants it.

 

If you are sensitive and would like to hear your engine revs, you will feel the difference.

I personally feel that the car runs better with 91