87, 89, 0r 93 octane fuel

[sweetwaterbroncoII]

Which is better to run....87, 89, or 93.....and for what reasons? I just ran a tank of 93 in my BII and my pinging and ticking went away....is that common?

 

[BlackBII]

It is common if your motor was built to run 93..which it wasn't. Unless the compression had been increased when you had it rebuilt.

 

[Rico]

In my ranger with the 2.3 in it, the higher octane helps it climb up the hills a little better only because my truck is geared really low. When the engine senses detonation it automatically retards timing a bit so the higher octane will help fight that.

 

[sweetwaterbroncoII]

Mine would tick like hell going up hills....93 seems to have gotten rid of the tick.

 

[exbass94]

Your engine is designed to run on 87. If it cannot run properly on 87, then there's something wrong with the engine that should be fixed. The only reason gas stations sell higher octane fuels is because some cars are designed for these fuels and need them to run properly.

 

[sweetwaterbroncoII]

That doesn't nec. mean there is something wrong with the engine....for all I know this engine has been rebuilt and has higher compression....I hope anyways.

 

[2low]

i run reguler all the time in my 2.9 but i went on a road trip and gas was cheap so i filled up with premium and it ran like a champ no misses, sputters ticks or nothing. then went back to reguler... and the old stubborn bitch came back with it

 

[Gotta_gofast]

Carbon build up is common and will cause pinging. So will "hot spots". A properly running engine designed to burn 87 octane fuel will in fact make more torque burning 87 octane vs. 93 octane. Higher octane fuel burns slower and colder while requiring hotter ignition to combust. A lower octane fuel will burn quicker and hotter and not need as much heat to start the combustion process. This is why higher octane fuels resist detonation (or pinging). The reason you experience more power with the higher octane is because it is resisting detonation and firing at the right time (expanding and pushing the piston down). When you run the lower grade fuels, the air/fuel is igniting too quickly and the impact of the force applied on the piston is at or a hair past TDC. Think of it as a bicycle. When you push on the pedal with your foot, you push as the pedal goes down. If you push when the pedal is at its highest point or just after, its extremely hard and not very productive. This is what is happening in your engine.

Before someone says "if higher octane fuel burns colder and slower than why would race cars use it". This is because of the extreme cylinder pressure. Pressure creates heat, and when used with lower octane fuel, that heat would pre-ignite the fuel and you have detonation and soon a trashed engine. Likewise, you can advance the igntion when running higher octane fuel because it burns slower.

 

[Beanmachine7000]

On my Camaro I use 93, because that's what it says to use, it has an 10.5:1 compression ratio though, lol... It runs okay on 87, it has less power because the computer retards the timing to keep it from detonating...

 

[PetesPonies]

Here's the accurate info. Octane is the fuel's resistance to burning. It has nothing to do with the BTUs the fuel has. Higher octane fuel is not more powerful. If you have no detonation or preignition problems running on 87 octane, you will get no advantage what so ever using higher octane fuel. You might as well roll down the window and throw money out as you drive.

 

[D-RANGER024]

So, i see that this post was, quite a while ago, i hope i still get a response. so i was driving my ranger the other day, and i put premium fuel in it, and now it wont even start. I've got it to start once with the full tank of premium. It literally got all these done that same day right before it stopped running, new plugs and wires, filters, fuel pump, and pcv valve. New oil filter and oil, mixed with lucas anti-leak oil additive. Any Suggestions??

 

[alwaysFlOoReD]

It's not the fuel.
Make sure the wires you replaced are in the right order.
Check to make sure you didn't knock an electrical connection loose.

 

[D-RANGER024]

Yep i did that, and in the process i noticed that the previous owner of this truck had attempted to bypass the inertia switch (located on the passenger side under the dash, on the firewall) and i dont know how that's supposed to be. but i was told, that could be the problem right there... i have a haynes and chilton, and i havent had a chance to read through those about it yet.... ill do that today

 

[D-RANGER024]

and i know that plugs are right, because it ran GREAT for the first 10 minutes when it DID start. but then it sounded like it ran short on fuel and puttered out.

 

[adsm08]

Have you checked fuel pressure?