Quote:
Originally Posted by Riceball1
All is good
I was just wondering if it was possible to change the timing on a custom tune. Many times when I go to Wisconsin you will find Mid Grade 91 or even 93 octane cheaper than 87. Maybe they just don't move it as fast as Reg.
Thanks for the help.
How many posts do you need to be a WHOPPER? 
Bob |
Hi again Bob -
You CAN change the timing on ANY tune (other than level 0). BEFORE you do this though, when you enter the "custom options" menu, go to "Load Previous Settings" first so that you reload your correct tire size and any other custom things you set. Otherwise, you'll just have default values in those places.
My Gryphon manual (really just an Edge manual), but Corey's updating it, says a rule of thumb is to increase timing by 0.5 for each octane count you go up. So, if you were tuned for 87 and had a full tank of 91 on board, you should be able to increase the timing by 2 degrees. What you'll probably have though is a mixture, so, if say you put a half a tank of 91 in and mixed it with 87, you'd really be running closer to 89 and should increase timing only 1 degree.
Use good judgment and you should be fine. Don't forget to reduce the timing when you start filling with 87 again, and don't forget to "Load Previous Settings" each time.
Sorry if I sound like I'm lecturing. I taught in the University here for 20 years and it sort of "sticks".
Somewhere in the f150 forums, I read that you could also increase timing for altitude. We're at 2500 feet here in Tucson and I tried increasing my timing by the smallest possible amount. I got a "wandering" idle and promptly set it back.
- Jack