Spark advance question

[99GTtony]

I have a 99 GT auto with the following mods: MAC CAI, Dragon Tb/PLenum, MAC prochamber, and magnaflows in the stock cat back. I put the standard performance tune on my car from the Diablo Predator hand held tuner. Today I went out and was doing some logging, just to see what the numbers were. We only have 92 octane here in WA. My car is running at 20 degrees advanced. Is this safe? What should I set it to if this is indeed to far advanced? Also does the diable show a/f ratio and where is it located, and what should the a/f be in a 99 4.6 PI.I dynoed a month ago on a mustang dyno, here's what I put down 217.2rwhp, and 229.6 rwtq. Are these numbers where they should be? Thanks in advance.

 

[99GTtony]

anyone?????

 

[MatthewP]

Your numbers are somewhere in the ballpark. My stock 02 GT was 209 HP on an MD-600. I doubt your total timing at WOT is 20 degrees. Those cars will take 28-30 degrees on 91 octane fuel in Calgary, naturally aspirated. That's at 3500 ft elevation though.

To check your timing, turn the datalog on, then run the car at WOT. I'll bet you see more than 20 degrees. Make sure the car is warmed up to full operating temperature when you run it.

The Predator does not log A/F, and there is no wideband in a stock Mustang. You will need a secondary wideband system to get your mixture.

-Matthew