I have a 88 TBI 305 motor that I am going to run till I rebuild my 383.I need to know what should I set the timing at? I know that you set it at 0* when using TBI but it will have a carb and nonCC distributor how much timing does the ECM add at idle?

 

set it around 6-8* advanced

 

Id set it up like any other carb motor. Some have said that the swirl port heads need less timing then the standard stock heads, which seems to be a safe assumption.

Some good values to use as a reference would be from the cop car tbi chip. They used around 17 deg. at idle, 28 during cruise, and a total of around 14 degrees at WOT, more or less, depending on what the conditions are. You probably cant run these exact values considering the curve of the dist. but they should be good starting points with a tbi motor.

 

Allright thanks guys

 

You want 32* @ 2,800 with the TBI heads and another 10* while cruising. That makes a total of about 42* @ 2,800 rpm. 2,000 RPM cruise usually results in just under 30* of timing which is perfect. Load the engine and the advance decreases.

8-12* Initial at the crank, 18-22 centrifical @ 2,800 (changes depending on distributer, etc reason the initial varies) and 10* @ 10 in/hg manifold vacuum advance.

 

Even more specific thanks Ill give it a try