I have thunderbolt distrib with a msd 6al box with rev limiter,do I need a jumper wire to set advance?I put my timing light on to the motor and revved to 3000rpm and the timing was way off.My builder says total 33 degrees at full advance ?shows about 45 degrees/The motor seems to run fine but my idle is off just looking at timing before I go any farther.

I would think at 45 deg total you would be detonating pretty badly, whats your compression ratio and what fuel are you using?

You will need to time it just like a stock engine. Ground the purple and white wire and set initial timing per the book. You can't really set total timing because that ignition uses a module that constantly varies timing, plus a knock sensor. If you want to control the timing you need to get a box that has a timing curve(like the Crane HI6-M), or install a TB IV module.

Ground wires from distributor?I have a separate module with a 5pin connector does that require the jumper?My engine runs 9.5 compression,93 octane solid roller ,dominator approx 700 lift dry exhaust so its kind of hard too hear.I dont think its detonating The plugs were changed last week and were black as the ace of spades and not white or melted.Just trying to get a handle on timing.

Are you running a TB IV or TB V ignition? If it's a TB IV then it is timed like a standard distributor. If you're running a TB V you really need to change it to the TB IV or get an ignition box with a timing curve. First off, the TB V tries to maintain an idle at around 650 RPM by altering the timing. With a big cam it's difficult to get them to idle worth a darn. You need to be able to control the timing curve.

Bobl,Called and asked they told me it was a 4 thunderbolt.My harmonic balancer is marked 0 and 36 degrees.I was told to run motor to 2500 (v-6 module) and find 33 degrees at o and turn dial on timing light to line up marks at o to check total.

No jumper wire needed. Get a variable advance timing light. Set at 33. Line up the 0 mark on the balancer and indicator at about 3000 rpm. That should give you around 22 initial at idle with the V6 14 module.
Gary

Thanks ,I might get a chance to mess with it thurs or fri.I will post results.I had to ask the question,Ihave timed motors before and this motor is new and a little more Hp, so caution is the word of the day.

Gary is right on! But you might find as much as 24 or 25 deg. at idle after setting up for 33* total at 3000 rpm when using a V-6 module. DO NOT CONCERN YOURSELF WITH THE TIMING AT IDLE USING THAT COMBO. The important thing would be to not exceed 35* total advance at 3000+ rpm. --- Jer

With the V 6 module full advance is in at around 1850.