I have a Mopar vacuum advanced/electronic/distributor in my rebuilt 440, The timing now is set at 25 initial and 36 total all in at I believe 2,300rpm's. I was informed that I should re-set it at around 18 initial. I have a little bit of knocking going on at medium throttle, and sluggish out of the hole but takes off great after cruising along. Can I adjust the slot/distributor with it still in the car or do I have to pull it out of the engine. I had help with it before, but just can't remember? Any instruction is appreciated! Thanks

Your total timing is adjusted using the slots inside, the initial is set at idle with the advance disconnected using a dial back timing light. Do you have an adjustable timing light? Is so set it at 18 advanced, back off the distributor to bring the timing marks to 0. Then bring the rpms up 2300 and check the total. It should still be at 36.

25 initial sure sounds like alot. I'd set the initial in drive at idle speed with the E brake on using the vacuum gauge method. Then with that # in hand I'd shorten the slots to get 36 total (checked with vac adv capped). Then I'd toss the heavy spring with the long loop on one end & keep the OE light spring for a baseline & want to stay just under the pinging point at WOT up thru the gears on your hottest driest day. If it pings you can add a mr gasket or MP light spring where the heavy spring was (along with the OE spring of course) or can trim the "tips" of the weights. Then hookup/adj vac adv by driving at a steady high vacuum interstate cruise at or above the RPM where the slots are maxed out & want to stay just under the pinging point on your hottest/driest day & can solder strips of feeler gauge on the back side of the can on either side of the notch to limit the arms' travel into the can. Can file the notches (both sides) if more travel is needed then with a 3/32" allen wrench slow the curve onset till you are just under the pinging point in everyday driving under varied conditions on your hottest/driest day. bottom line stay as close to the pinging point within reason as you can and any pinging you can hear is WAY too much. To get you primed right now with a 3/32" allen wrench into the can nipple turn it 2 turns CCW & see if the medium throttle pinging you have goes away. Do each subsystem in order: initial/total/springs/vac adv (2 parts)

I'd leave it as is and back off your total number until you get the knock under control and see where you land.

Nobody can tell you what the engine wants for initial. If it starts and runs with 25, so be it. I have a couple engines that have 24-26 initial, no pinging because the total number and curve are right.

torkrules, Yes as you mentioned it is one of the newer units based on a Mallory distributor (from what I have been told). This set up is in a 1969 Road Runner with 3:55 gears, 727 stock rebuilt trans with a shift kit, the motor is a totally re-milled 440 /.30 over with a Comp Cam 268 xe hydraulic cam, original re-worked iron open chamber heads, forged pistons, stock Mopar intake, Holley 750 double pumper carb mech. secondaries, Changed over to electronic ignition with the new Mopar distributor mentioned above. Thanks for everyone's input!

You can do it with the distributor in the engine but why? You still have to loosen it up and rotate the distributor to reset initial. Why risk dropping a small screw where you don't want it to fall ?

This curve from Rick at Mopar Action works great in the 440's I've tuned -

http://www.moparaction.com/Tech/quest/SLOW_CURVE.html

Bob, assuming sufficient octane vs. C.R., you need a curve something close to this:

Under 1400RPM - no advance - set initial at 15 degrees BTDC
2000 - 10 dergees mech (25 total)
2500 - 20 degrees mech (35 total) - all in.

Plus, at LEAST 15 degrees of vacuum advance under light throttle (50 deg. total, 52-55 better).

If it currently doesn't go to full advance until 5500, you're giving up lots of power.

If it currently has less (or no) vacuum advance), you're giving up LOTS of fuel economy and fouling plugs.

Rick

What are you doing with the vacuum advance?


And more about the motor and cam.

When i hear sluggish off the line I think vacuum advance hooked to manifold vacuum and being part of the initial and total timing??