Ignition Timing
 

Got a 87 formula 272 with twin 350's. Its got thunderbolt IV ignitions on them. whats the best way to set the timing and is there any special procedure. What should it be initial. and what should the timing be total and at what rom should i set it at. thanks

You need to ground out a pin but I cannot remember which one. Hopefully somebody will not be as braindead as me :D

I hope there is no pin to ground for thunderbolt IV ignitions or I have been doing it wrong for 20 years.:eek:

Set the base at 8 degrees and you will be fine. If your module is 24 that will give you a total of 32.

I agree. Use a good timing light and check base timing at idle and manually rev the motor to around 3K-3500rpms to read full advance.

Merc TB V8 modules are either 22 or 24* advance. 32* total is fine for a stock 350.