gas
- Thread starter 03silverv6
- Start date
Skymarshal
Member
Putting premium gas in your Mustang will not result in better mileage. The engine in the Mustang does not have a high enough compression ratio to require higher-octane gas.
For cars that specify premium gas, using regular gas can reduce mileage, since most engines have a knock sensor that will retard timing and/or adjust the mixture if lower-octane gas causes detonation. That will hurt both power and mileage.
For cars that specify premium gas, using regular gas can reduce mileage, since most engines have a knock sensor that will retard timing and/or adjust the mixture if lower-octane gas causes detonation. That will hurt both power and mileage.
Adverse2Change
New Member
I've regularly put 89 in mine due to all of the spark knock I get when I've run on 87. Any higher than that for me would be a waste.
The spark knock on 1999-2000 V6's was due to a wonderfully designed valve cover that allowed oil vapors to easily pass through the PCV and into the intake. Oil will drop your overall octane rating, hence why you get a slight knock and have to use 89 octane. You can either keep using 89 octane, install a filter into the PCV, or spend $$$ on revised 2001-2004 valve covers with the baffles that are supposed to keep the oil out. If I ever get around to it, I'm going filter route.
http://www.miracerros.com/mustang/pcv_filter.htm < there's a site about it.
As far as using a higher octane than needed, you don't burn all the fuel and it's either doing to sit there as carbon build up (bad), flow out the exhaust (wasted and emmissions), or worse yet, go past your pistons as deposits and wreck some havok down there. Once the damage is done, well you're stuck using a higher octane because all the build up raises the compression ratio some and decreases the overall chamber sizes so you get even less power all while wasting more money. A loose-loose situation.
http://www.miracerros.com/mustang/pcv_filter.htm < there's a site about it.
As far as using a higher octane than needed, you don't burn all the fuel and it's either doing to sit there as carbon build up (bad), flow out the exhaust (wasted and emmissions), or worse yet, go past your pistons as deposits and wreck some havok down there. Once the damage is done, well you're stuck using a higher octane because all the build up raises the compression ratio some and decreases the overall chamber sizes so you get even less power all while wasting more money. A loose-loose situation.
trock
New Member
Skymarshal
Member
TMX said:
If you have carbon build-up in your engine, with the associated carbon knock (preignition due to glowing carbon on the piston from the previous power stroke), you can run any fuel system cleaner through the engine and clean it out. You don't need to accept the need to run higher octane gas- it's not permanent damage.
Adverse2Change
New Member
TMX said:
Thanks for the link TMX... this may actually be worth trying. I was getting the 89 octane not only to help with the knocking, but like trock said it was the cheaper at this Hot spot gas station than 87 octane was at every other gas station.
Adverse2Change
New Member
Felt motivated, so I went ahead and installed an inline filter. I'll let you know if it knocks out my knock. 
trock
New Member
actually it is the same gas station. 87 and 89 octane are both 2.95 at the same time, 93 is like 3.12 or so though.
Course, I'll admit to the same. 89 is 2-3 cents more for me, and I know I have the oil blow by and that's the reason the 89 helps, but it's POURING outside on the one day I have off work and wanted to install the filter and clean my air filter booo =(.
Adverse2Change
New Member
TMX said:
It definitely collects a lot of oil for me (~35 miles at 65mph typical). No knocking as of yet, but I want to run some cleaner through my engine before I vote this as the best mod ever! I acutally routed mine down around the spark plug wires, mainly to keep it a bit hidden and to protect the glass filter from accidental breakage.
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