to use the scanmaster as a tuning guide would be great if i knew what the numbers mean can someone give me a explanation also... the o2 volts are never steady even at a cruise they jump from 0-700 the real problem is pinging i have lowered the boost but still i get pinging this is what i have....stock injectors, to4H, thrasher chip ,walbro 340 hot wired ,ram air ,160 stat ,kenne bell adj. f p r , (fuel pressure is at 45 with line off) adj wastegate set at 14#, after a WOT pass or as much as i could (pinging) the o2 volts are at 790 and the retard reads from as high as 11.2 to as low as .7 any suggestions?
scanmaster numbers???????
- Thread starter drive805
- Start date
I think on the Thrasher you can only raise your FP to 47 max.
02 jumping all over the place are not a problem. You tune to you WOT 02 numbers. 790 is normally good but y'all have very poor gas (low octane) and I saw posted where it got worse 2-3 months ago. Even with that, something is wrong because you are getting to much knock with crappy gas.
What I would do: run some xylene with your gas and get some WOT figures to report. If it goes down, then your problem is octane or the lack of it. To cure, you will need to run xylene or go the alky way. You need to have less than 4 degree of knock and you try for 0.
If you still have high knock, then it might be false knock: DP hitting frame or in my case a transmission slipping.
PS Are you for sure your FP rises as you get into the boost. Remember FP must rise 1# for each # of boost.
02 jumping all over the place are not a problem. You tune to you WOT 02 numbers. 790 is normally good but y'all have very poor gas (low octane) and I saw posted where it got worse 2-3 months ago. Even with that, something is wrong because you are getting to much knock with crappy gas.
What I would do: run some xylene with your gas and get some WOT figures to report. If it goes down, then your problem is octane or the lack of it. To cure, you will need to run xylene or go the alky way. You need to have less than 4 degree of knock and you try for 0.
If you still have high knock, then it might be false knock: DP hitting frame or in my case a transmission slipping.
PS Are you for sure your FP rises as you get into the boost. Remember FP must rise 1# for each # of boost.
- Joined
- May 24, 2001
This link should help you out:
http://www.gnttype.org/maint/quickref.html
When you say the car is "pinging" what numbers do you see in the "retard" section of scanmaster?
http://www.gnttype.org/maint/quickref.html
When you say the car is "pinging" what numbers do you see in the "retard" section of scanmaster?
more info
the octane here in so cal...is 91 supreme unleaded... the fuel pressure rises with boost aprox. 58 when pinging starts and i back out of it the retard has read as low as .7 and as high as 11.7 checked for a rattle on the down pipe it's stock so its not close to the frame but the heat shield was loose tightened it didn't make a difference for higher octane gas.... its expensive about $4.50 a gallon
expensive to drive everyday
the octane here in so cal...is 91 supreme unleaded... the fuel pressure rises with boost aprox. 58 when pinging starts and i back out of it the retard has read as low as .7 and as high as 11.7 checked for a rattle on the down pipe it's stock so its not close to the frame but the heat shield was loose tightened it didn't make a difference for higher octane gas.... its expensive about $4.50 a gallon
expensive to drive everyday 
