Someone please help me understand this? On 85 TPI, stock GM chip, 92 octane, assume optium total timing to be 38*. If base timing is set at 8*, does this mean timing in chip ( added by chip ) is 30*? 8 + 30 = 38!. Is this how it works? Comments? And also, I,ve heard of guys TEMPORARLY unhooking knock sensor, increasing timing 1* at a time until knock is detected, then backing off 1* or 2*, hooking knock sensor up again, and calling it done. Comments? Thanks in advance.
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Yes, you've basically got it right. Initial setting on most 3rd gen V8s is 6* BTDC. The chip will usually add about 26-28* more in the programming, giving you about 32-34* total at WOT. With a stock chip and good gas in the tank you can usually bump the initial timing up another 2-4* for a smidge more power.
Unplugging the knock sensor won't work by itself. You need to trick the computer into thinking it's still there or it will throw a code and start running in "limp home" mode. Fortunately, this is easy to do. Just plug the knock sensor wire into a 3900 Ohm resistor (Radio Shack- $.18) and then on to a good ground. The ECM will think the knock sensor is still there but obviously won't ever register any knock.
Unplugging the knock sensor won't work by itself. You need to trick the computer into thinking it's still there or it will throw a code and start running in "limp home" mode. Fortunately, this is easy to do. Just plug the knock sensor wire into a 3900 Ohm resistor (Radio Shack- $.18) and then on to a good ground. The ECM will think the knock sensor is still there but obviously won't ever register any knock.