scanmaster tips?

[edwin]

i was wondering the ideal o2 voltage, whats the lowest you can go,and the highest knock reading at where you should get off the gas,also is it normal for it to start up cold at around 370, although is fluctuating between 170 to 630 which usually indicates a healthy sensor, but i could use some feed back on how other cars work,thanks

 

[OKTurbo]

Basic info at http://www.gnttype.org/maint/quickref.html

The O2 mV will jump all over the place until you go WOT. The computer is adjusting things while in closed loop....WOT is open loop. Generally speaking, at WOT you don't want to go below .780 (or so)....but this also depends on whether you're running pump gas w/ street chip or race gas w/ race chip. I like to keep it around .800 with pump gas for an extra margin of safety.

The best indication of O2 sensor condition is the O2 cross count number....CC on the scanmaster. This tells you the number of times the O2 sensor switches from rich to lean during each "cycle" of the ALDL data. CC should be 10 to 20 when everything is warmed up. If the O2 sensor starts to get "lazy" these numbers will go down and it's time to put in a fresh sensor.

As far as Knock Retard goes...I like to tune for zero KR at the track....no more that 1 or 2 degs at the shifts. Same for the street. If you see more that about 7 degs at WOT you'd better lift your foot or it might start getting ugly. It does you no good to run a lot of boost if you're getting KR. The computer pulls the timing and it slows you down. Might as well turn the boost down and tune for no KR....you'll have a better chance of going fast.

These motors are very tough. I've seen these cars take a LOT of knock retard...mostly due to an overboost problem and survive just fine. But I wouldn't make a habit of it.

John

 

[edwin]

thanks for the input