When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I know the timming on an 86 L98 is -6 btdc. I have read post on changing it to -4 or -2. By doing this are you advancing the timming or retarding it. One more thing. set timming in park or drive with est dissconected
If you change the timing to 4 BTDC or 2 BTDC then you are retarting the timing because the computer will fire later but if you got to 8 BTDC or 10 BTDC then you are advancing the timing....you should have the car in park and est dissconected.
jtfrog: I run my 89 L98 at 8 degrees before top dead center (BTDC) of the #1 piston. The spec from the "General" is 6 degrees BTDC. Not sure about the -6 etc mentioned in above posts???? I get good throttle response with this timing setting and the TPS set at .65 volts. Make sure you unplug the timing connector before you make the timing adjustment. Hope this is helpful!
As far as the timing mark goes with the motor off look at the balancer and find the grove then take somthing (white chalk or a silver sharpe) and mark it. After you mark it start the car and check it it should show up clear as day. For what its worth if it is running fine mark down what the timing is at now before you adjust it for a referance then adjust it and if it runs worse put it back where you found it. The other alternative is to leave it alone.