Whatever. In your strange world less spark advance makes you go faster.

Everywhere else, people run as much a advance as possible until 1) the car doesn't make any more power, or 2) it knocks.

Here is another example where I have responded to the OP, and you had to chime in and reply directly to me because you are uncomfortable that someone else might know what he is talking about. You go ahead and continue to argue with Onyx about how running less octane than what GM recommended is fine.

Hey, whats the FSM say?


-- Joe

 

He is upset because you don't have a clue what your talking about. You seem to think because your TBI car runs fine on 85 octane, that somehow translates to how an LT1 will run with less octane. You've proven time and time again you have no idea how these computers are programmed, yet even though your limited range of knowledge is based on guesses you have no problem attack those of us who have been building and modifying these things for years.

Here is some information for those who understand, unlike Jim here who thinks "the more spark advance you can run, won't make more power". Because Jim here has a slow turd that runs on 85 octane.

Here is one of the many tables the ECM uses to deal with low octane. After running for a while, the premium fuel bit will be set or unset in mosts masks. (this logic is MUCH more advanced in the LT1 bins, although my example is $8D).

http://members.cisdi.com/~anesthes/low-octane.jpg

And here is an example of what happens when your motor is tuned to a specific octane (the example here is '93) and you try to get away with '89 octane)


http://members.cisdi.com/~anesthes/low-octane-log.jpg

Notice how much spark retard ? The total commanded advance would have been about 29 degrees, but at some points it takes away as much as 6-7 degrees of advance total, leaving you (me) with around 22 degrees total advance. Some people say for every degree of advance you can get away with, you'll unleash about 10hp. If thats true (which those of you who have dyno tuned their built motors will know - again not a stock '84 running 85 octane) we're talking a 60-70hp hit.

-- Joe

 

I can't believe you asked to have that explained. On second thought, yes I can. When you have too much. In that case less advance would "makes you go faster". That would be obvious most everybody else.



According to you, that isn't possible. If "The more spark you can run, the more power you can make." how could "until 1) the car doesn't make any more power" ever happen? According to your profound statement, "The more spark you can run, the more power you can make. It's pretty simple really."", condition 1) can never occur. "It's pretty simple really."



It isn't the people that know what they are talking about that make me uncomfortable. It is people like you. And despite your denials, your innocent response to the OP 20 posts later, clearly referenced your obsession, me. Then in post 49, with no reference by me to you or your post, you attacked me with no reference to the OP or his question. Your ONLY subject was me. Here it is, before you edit it: Post #49, 3/13/08, 01:36 PM. RACE ON!!!

 

Play nice or

 

Aah, yet another thread with half the posts not pertaining to the topic. Please take your bickering to PMs people.

To the OP: If the manual says to run 91 octane, run 91 octane. Despite what anyone on the internet will say, the designers of the engine know more than they do. So they probably have a damned good reason for saying to run 91 octane. If you want to cut fuel costs, drive a bit more conservatively. Don't give me that "I already do" BS, I own a Vette too, so I know you get onto it.

 

Let's just ahead and shut this down.

If you all can't play without subtle attacks we won't play.