So I've installed the DS2, curved by wsa11 (thanks Bill!) for my street use. After a couple conversations with him, and some reading I've come to the following understanding of timing advance. But something is off. Hopefully you can help.
For the tuning, start it up and let her warm up. Once warm set the timing advance with the vacuum unplugged from the distributor.
- The ford manual for the 67 Mustang (AT) says to set advance @ 12 degrees in drive.
Ive read that with DS2, add 5 degrees to stock max = 17degrees
The MSD manual says to set the plugs at 45-55 gap, so I set 54
Bill set my distributor @ 18 degrees initial advance
Curved to about 36 degrees max
(was still using the 1bbl carb)
When I set the initial advance in park (I'm solo) at ~650 RPM the engine runs rough at 17 degrees. Worse with less. Happy point is around 20-24, where she runs smoothest. Ok, set to 17 degrees, plugged in vaccum port and went for a drive.
All was ok, except at WOT I get what sounds like a buzz. I'm assuming this is detonation. I stopped doing that. In drive, stopped, the idle was very rough and shaky. But it ran. So I installed the Weber 32/36 last weekend. It's in and running, but pretty rough. Once I get the gas pedal hooked up and the fuel regulator installed, I'll try and dial it all in.
My understanding of advance is that:
- Initial advance (18 degrees)
is added to measured advance (17 degrees)
This gives 35 degrees advance at idle?
This seems a little excessive. Am I misunderstanding something? Dialing in the Carb and DS2 together is going to be a PITA if I don't get the theory down. VI ships the Weber jetted already, so hopefully that'll not be an issue.
Thanks in advance!