I understand your point, but the one I am trying to make is that running 89 octane greatly reduces the chance of having a failure. I'm sure the 87 octane alone is not the ONLY cause, but when combined with one or more of the conditions you mention, it is a contributing factor.

Just like all smokers don't contract lung cancer, but when you factor in other influences like envonment, genetics, etc., the smoking is still a large contributor and someone with all the other symptoms who does not smoke stands a much better chance of NOT getting it.

If you follow my analogy...

 

Thanks Hammer

 

This is inaccurate. An auto trans will coast in drive with the motor off.




No one has mentioned what altitude they are at in relation to what octane they run.

If I remember correctly the hemis have 12:1 compression stock that requires premium fuel AT SEA LEVEL.


More altitude = less compression. Less compression = lower octane requirements.

Bottom line is-if your motor doesnt ping, it doesnt really matter what octane rating you run. It could be 75 octane fuel. It doesnt matter as long as it doesnt ping.

What altitude am I at?
Is the motor going to be under a load a lot? i.e. leadfoot driver or loaded with tools cause its a work truck or frequently tows a trailer?
is the motor stock in the compression department?

 

Uh, no the Hemi does not have 12 to 1 compression. It has more like 9.6 to 1 compression.

Just because you don't hear detonation, doesn't mean it isn't happening. By the time you hear it, there is some pretty violent tings happening in the combustion chambers.

Never run lower than 87 octane in a Hemi. I have never ran less than 89 in mine and never will.

 

hmmm...your right, guess I dont know where I got that info from.

anyways....IMO less than 10:1 makes the grey area even wider as far as octane rating goes.

 

I have never seen an engine let go quietly. There should be codes, clouds of oil, banging and clanging. Maybe a few dents in the hood and flat tires from running over broken parts. Ok, maybe I got carried away. anyway my guess is, no codes points at a PCM failure. Good luck..

 

run at least 89 in the hemi, you dont put 87 in the WS6 do you? if so please stop now

 

Alright everyone..stand back..

 

thats not being a troll dude, funny though

 

Troll indeed. He posted one topic (his only post also) about his "blown engine". The thread received its attention, and he never came back.