'66 GT350 Hertz Automatic Timing

[Shelbybo1]

Had some work done on my 289 K code original engine.
Needing to know what the timing at Idle should be set at??

Since it is an automatic trans car (C4), should the timing at idle be 6 deg

Thanks

[NC TRACKRAT]

Suggest you just adjust timing for smoothest idle.  I like to extend the radio antenna while I rotate the distributor and look for the least vibration.

[greekz]

I have always set my timing to what the shop manual indicates.  Both my engines are in stock configuration.  Never has an issue with performance.

[Shelbybo1]

Any idea what the shop manual recommends??

[Bob Gaines]

Any idea what the shop manual recommends??

Surprisingly the shop manual doesn't give too specific of timing info for a 289 Hipo. 8-109 in the 66 shop manual . The Tony Gregory 289 High Performance Mustang book lists the timing specs of 10-12 BTDC 650 rpm  for auto and 750-775 for manual. 

[Bob Gaines]

6 degrees is what is listed for non hipo.

[pbf777]

       Just do realize that what the "shop manual" will have listed is what would be considered by "engine guys" as being values of known conservatism; so unless your environment is of one of the extreme, timing values of something more aggressive will most definitely reap you something better in the function of your vehicle performance, and even efficiency wise.   

       But, I would recommend to always utilize a proper timing light for aid in proper processes of adjustments made and so that proper conclusions may be had;............... aka. no twisting & fishing blindly, till it seems to sorta sound good!   


       Oh, and by the way, the bulk of that which dictates ignition timing values in a reciprocating internal combustion engine is not so different between a "standard" 289 and the "Hi-Po" 289, so I would gather that this is the reasoning for there to not be "special" timing sums listed in the manual.   

       Scott.

[Shelbybo1]

Thank you for all your inputs and recommendations.
r/,
Jimbo