Im sure there are a few HPTuner users in here. Came across this and figured some of you might be interested in this.

Someone put a lot of effort into this.

http://home.insightbb.com/~black02ss...uning_info.doc

 

yeah i saw this on ls1tech and saved it immediatly.. lots of good info..

 

what are some disadvantages of copying your high octane table into your low octane table?

 

If you detonate and the PCM switches to the low octane map, you will still have detonation.

 

bah, pcm will retard timing as soon as it sees knock, regardles of the timing table.

 

Dave is right, likely the knock sensors will pick up any problem and save the engine. I'd still keep the low octane table with less timing than the high octane table though, just for good measure. Just bump it up the same as the high octane table when you increase it (i.e increase both by 2 in the same areas, etc...). I can't say I've ever seen a car run opn the low octane table myself though.

 

problem ( as I was told ) is the pcm is always running a variable of the high octain *vs* low octain table , never just one or the other . . it just depends on the % it chooses to grab from each as a multiplication factor. If your tuning your car for peek power without knock its too hard to know which variation of the timing tables the pcm is using so they paste over the low oct with an exact copy of the high oct table after each edit, this way you know exactly where your at at all times. . . .

I suppose after your done tuning you could take your tuned high octain table, knock it down a % and paste it into the low oct table but from what ive read, you would be back to splitting the difference. Low timing tables = pointless me thinks for 99% of us who dont lend out the car or fill with 87 oct.