Please help, Spark Advance w/Predator

XStanger

Founding Member
Sep 1, 2002
383
0
16
I have been tweaking the car with the spark advance parameter with my predator and I have a couple of questions.

1. I have made 2 increases (.5 each time) from 2-4k rpm range, do I continue to increase until I hear detonation and then back it down .5?

2. Should I make the same increases to the 4-7k range as well?

BTW, I am making these changes while car is at operating temp and then making several full throttle passes listening for detonation.
 
  • Sponsors (?)


propellerhead said:
Do be scared. Many of us have gone to +10% in both ranges. Start there and move backwards by 1.0% if you hear detonation. If not, enjoy it.

Agreed. I have run my '99 GT with both ranges maxed at +10% and didn't hear any detonation. I have basic intake and exhaust mods. Should be pretty safe. Right now I'm running the factory tune with timing maxed...don't ask me why I've just been trying to compare it against the predator tune.

Once I had the timing maxed and tried leaning up the air/fuel by 6%. I heard pinging at 3-4 k in third gear at WOT, so seemed like the predator tune was set pretty well for air/fuel as is on my car. So, I just put the fuel back in.
 
so needless to say that the minimal advances I have made are nothing! So what you guys are saying is max the parameters? Right now I have them at 1.5 in both ranges, so I will take them to 10!! :D I have noticed a little difference on the low end so far.

This may make a big difference because when I had the car dyno'd last year before mods the car was very pig rich. My A/F ration was 11.5 throughout the rpm range!
 
swl987 said:
what octane do you guys run with the timing maxed? i can get from 94 and down but if i only need 91 or 92 then why bother looking for a sunoco station and paying more.
We can't answer that over the Internet. Only you can.

Bring you tank to near empty. Fill up with 92. Run that for the next week and listen for pinging at WOT. Back off the timing advance, or go with 94 if you hear pinging.
 
propellerhead said:
WOT during bumper-bumper traffic? Damn!

its a different animal :nice: tested last night after my rc session

what i meant initally was testing in bumper to bumper traffic. because i was under the impression the spark advance was throughout the entire throttle range. :nonono:

sigma pride cleared that up though :D

i dont think many ppl would be happy hearing the LM going off in neutral in the middle of traffic needlessly :rlaugh: