Lower octane in turbo engine

[PZR2874]

You could always do the #'s and put one gallon of ethanol and the rest 91.... You have a 14 gal tank ?

 

[poiuy223]

Finally emptied my tank of 91.

Previous fill of 87 -- 429mi, 16.6gal (purchased at $3.87/gal, 91 at this time was $4.09/gal)
Emptied fill of 91 -- 452mi, 16.5gal (purchased at $3.97/gal, 87 at this time was $3.87/gal)

The 87 fill was emptied over a weekend -- plenty of highway runs and a few short local trips
The 91 fill ran about the same highway, but because of the higher MPG and the gas saved, it allowed me to go through 2 extra days of local work commute of about ~50mi.

 

[rslifkin]

Sounds like it's definitely worth running 91 in there!

 

[06jds377]

Your manual likely states that minimum recommended is 87, which is by recent govt reg iirc...

You'll knock a couple of times under load (you won't notice) and the ecu will pull timing. You'll likely lose somewhere around 20-30hp off peak.

Don't cheap out and listen to the guys who beat the manual to death, turbocharged engines require a higher octane to run at their max rated power level.

I'm proud to say in the 50k I've owned my boosted four it has never seen lower than 91.

 

[Scum_Frog]

Run with 91!

 

[jeff_george]

In a convensional indirect injected engine with a tubocharger. then higher octane would be required. New direct injected engines which have been engineered for 87 octane would require just that. Does your fuel door state 87 as a minimum?If so then you should run a higher octane fuel unless you REALLY baby your car, with mostly easy highway cruisng to ensure long engine life. Look at the chevrolet cruze- 1.4L turbocharged, direct injection. 87 octane is SPECIFIED for this car. Is you car direct injection?