440 Engine tuning suggestions
@Newbomb Turk So basically the answer is we get fully programmable ignition systems?
There’s only so much you can do with stretching springs, advance weights & vacuum canisters.
At some point…yes.
I may be at that point with my junk. It looks like it will be a bit over 12:1 compression. Like 12 and a quarter. I won’t know until I do the down fill and the math but it won’t be less than 12:1.
I absolutely want to run vacuum advance. I’m also going to run manifold vacuum to the fuel bypass regulator.
That will reduce fuel pressure as manifold vacuum goes up. It has a similar effect like VA by reducing fuel pressure at idle and cruise and by doing that it leans the carb out.
My initial thinking is I’m going to need something like 20-22 initial, maybe 26 at peak torque (that should be about 5200ish) and 32-33ish at 6700ish.
If I’m even close on my numbers it’s going to be hard to get that curve.
I may have to wind my own springs (PITA), see if I can buy a spring with enough rate to control the weights or/and modify the weights.
If I can’t get what I need then I’ll have to buy a crank trigger and a Programmable Digital 7 from MSD.
I really do NOT want to do that.
If by some miracle I get the curve acceptable then I need to start working on the VA.
Or, I could shove an ice pick in my ear. That may be easier on me than getting the curve correct.