Thunderbolt IV Timing 383 Stroker
 

I'm trying to get the timing set on my Baja with a Thunderbolt IV ignition. The dist. was pulled for some engine work last year (it was replaced properly) and the spark hasn't seemed right since. The engine is a 383 with Alpha drive. When trying to time the mark is jumping making to hard to time. As far as I know there are no jumpers or wires to ground while timing. I'm shooting for 12-15 deg of intial advance for my setup.

Any input would be greatly appreciated!

Sounds like maybe you have a bad module but not real certain. did you try and use a different plug wire to rule that out. if you have a short somewhere that will cause your light to jump a bit. otherwise just time it for full advance at 34 deg or where ever your wanting to be.

Fixx
 

do you have a msd box also?

I have not tried that, I will tomorrow, I can't time it using a different wire can I?

I have a MSD Blaster coil but everything else is stock ignition wise.

Just swap it out with another one. pull number 2 wire and switch it with number 1 wire. otherwise perhaps your number 3 wire is long enough to fit number 1 and you could switch them on your distributor. i know it's doubtful however it is possible you have a cracked plug also. is your engine idling down like it should and running smooth?

It runs great on muffs, way better since my attempt to time it a couple days ago. Before it would start hard and then hesitate when given throttle. I advanced it quite a bit, not sure but it's possible it was quite retarded before. The idle was around 500rpm before and now around 700-800rpm and responds right away when given gas. I haven't had it on the water yet this year and wanted to be sure about the jumping before doing so.

Any input on what I could replace the stock ignition setup with?

Chances are you have a weak ground somehwere or slightly bad connection. I highly doubt the module is bad. Modules usually just quit or don't advance at all.

Where is idle rpm and what module???? It could be that the advance is just starting to come in at the rpm you are at. You really need to set total timing and let base fall where it may.

The idle rpm is around 800-850 rpm, and the module is a Thunderbolt IV. From my research it sounds like that module will only advance to a total of 24. probably too low for my 383. I'm probably gonna end up getting a MSD ready to run distributor so I can just set my own curve.

I always thought the T-bolt IV advance was in addition to the initial timing. If you want 32 degrees of total advance set initial at 8 degrees and when the T-bolt is all in you are at 32.