Originally posted by akrump47:
Here is what is happening to Jim's engine and anyone else who is putting cheap gas in their SVT:

http://www.caranddriver.com/article.asp?section_id=4&article_id=3604&page_number=1

Some quotes from the article:

"The results were more dramatic with the test cars that require premium fuel. The turbocharged Saab's sophisticated Trionic engine-control system dialed the power back 9.8 percent on regular gas, and performance dropped 10.1 percent at the track. Burning regular in our BMW M3 diminished track performance by 6.6 percent, but neither the BMW nor the Saab suffered any drivability problems while burning regular unleaded fuel."

"Cheapskates burning regular in cars designed to run on premium fuel can expect to trim performance by about the same percent they save at the pump. If the car is sufficiently new and sophisticated, it may not suffer any ill effects, but all such skinflints should be ready to switch back to premium at the first sign of knock or other drivability woes."

Once again I say - If you want to save $2.40 a week, why do it by retarding your car's engine performance. I could save the cost of an entire months worth of premium but not eating lunch out once a month.





This is certaily not an issue that is going to be resolved on this thread.

This idea that detenation that you cannot hear is likely to do damage is not universally accepted. For example this is a quote from page 163 of my owner's manual. "Do not be concerned if your vehicle sometimes knocks lightly. However, if it knocks heavily under most driving conditions on the recommended octane, see yhour dealer or a qualified service technician to prevent any engine damage."

Actually, Ford even taught me in their traning programs that ocassional slight or trace ping is an indication that the engine has been optimally tuned. This was before computerized engine controls though.

Actually, I'm mildly disappoited that my car was factory tuned so that premium fuel is not that critical. I'm also disappointed that there has been so little equipment wise to enable me to tinker with the settings that I used to be able to do by hand.

In my capacity as a service manager, I have worked on and driven cars that had knock sensor systems that seemed to be much more sensitive to fuel grade than my SVT. Both Volvo and BMW come to mind, where you could substantually feel the difference.

If it makes you feel comfortable to think of me as studid or misinformed, then so be it. I am neither.

Jim Johnson 98 SVT 03 Escape Limited