View Full Version : Ignition: Ignition advance

03-02-2018, 08:09 PM
I have received my Billet distributor I am setting the max advance. The kit comes with 3 set of springs And 3 sets of advance stops. I have an old Sun Company Tune. Up spec chart that list the advance curve.The Sun Chart calls for 11- 13 at 2200 rpm. With no advance stops max dist mech. Advance 19 degree at 3400 rpm.
Looks like I may have to bump up the initial advance .The medium springs provide the closest curve to specs on the SUn Chart.
Any thoughts.

03-02-2018, 08:29 PM
Make sure you don't get distributor degrees and crank degrees mixed up. The distributor turns once for every two turns of the crank.

If they are talking about max distributor degrees being 19 degrees, then that is equal to 38 degrees at the crank.

What year and which engine? Any mods at all from stock; i.e. compression ratio, cam etc.? EVERYONE who has ever played with distributor curves has an opnion, me included.

Unfortunately, almost all my "playing" is on Chevy engines. The basic theory will be the same, but the numbers may be different.

03-02-2018, 08:48 PM
The Chart tha came with dist.uses engine rpm the Sun Chart uses distributor RPM 62 289 Cam ? Comp Raito?bored 60 over.

03-02-2018, 09:09 PM
So the chart that came with your distributor indicates the max centrifical advance you can get is 19 crank degrees? Seems a little extreme (on the conservative side). Might double check the language there.

To get a TOTAL of 36 degrees (not counting vac) you would need 17 degrees initial. I have no idea if a Stude will accept that, but someone on here has probably tried it. My higher compression Chevy's do not like more than 10 to 12 initial or they tend to "kick back" when starting. Very hard on starters to do that.

03-02-2018, 09:45 PM
What KIND of a "Billet Distributor"?

03-02-2018, 10:24 PM
Maxx Performance From E bay

03-02-2018, 10:36 PM
The sun chart i have says Cent advance only 22 to 26 with the 4 degree initial it would be in range would it not? 13 in of vacuum should give 7 to 9 degrees so that should get close if my math is correct. 4 + 19+9 would be 32 .

03-02-2018, 11:54 PM
Look at your card a little more closely. The vacuum advance is 7-9 distributor degrees. The "total advance" is up to 44 degrees at the crank PLUS the initial 4 degrees, for a grand total of 48 degrees. With your 19 degrees of cent, it would be 4 + 19 + 18 for 41 degrees. But that is ASSUMING the new distributor has the exact same vac advance total as your old one. Does it indicate how many vac advance degrees you have?

Part of the confusion is that most articles and most guys referencing "total" timing are ONLY referring to initial plus centrifical. I realize this does not make sense, but I believe it comes from all the experimenting done by drag racers who don't use any vac advance.

Like I said, everyone has opinions, and mine is shaped mostly from playing with Chebbies.
Most Chevys run best with somewhere around 36 degrees total, EXCLUDING vac advance. 26 degrees advance with 4 degrees initial only gets you to 30 degrees. I believe a lot of Studebaker (or at least some) simply run 8 to 10 degrees initial to get 34 to 36 total.

I would like to hear from Jack and some of the other guys on here with extensive experience with Studebaker V8 engines. I did find an old thread discussing some of these issues:

The biggest bone of contention appears to be whether the Studebaker V8 will run better with the vac advance hooked to "ported" or manifold vac.

Personally, I have found the Chevys to run best with initial and centrifical totaling 36 degrees. Vac of up to an additional 15 degrees in most cases, but only connected to manifold vacuum. I have a 350 in my 68 El Camino set up exactly like that, and even using regular gas in a 10:1 compression motor, have no issues. Throttle response is amazing. I was even able to go one size smaller than the factory main jets on the carb and still run great.

I don't see any reason the Studebaker V8 would not respond to the same type of spark tuning. I never saw anything in the previous discussion to make be believe otherwise.

Just to see how it goes, if I were in your shoes, I would install the distributor with no stops (to get the max advance possible) set the initial at 10 degrees, hook up the vac advance to manifold vac. and see how it runs.

03-03-2018, 12:24 AM
Theres a guy on the Fordsix forums named wsa111, he does nothing but distributors. Ask him for advice if you need any. He also will curve them for $75, then more if super special springs are needed.

Good luck,

03-03-2018, 09:03 AM
The centrifugal advance rate for stock 259/289 engines is 24 crankshaft degrees at 2400 rpm. The R1 engines use 20 crankshaft degrees at 2400 rpm and the R2 engines use 16 to 18 crankshaft degrees at 1600 to 1800 rpm. These numbers come from the distributors I have tested over the years on my Snap On distributor machine. If I remember correctly, these numbers correspond to what is in the shop manuals. Bud

03-03-2018, 09:14 AM
Thanks for your in put that is what I plan to do. But I am setting the initial at 6 degrees in my mind you are counting the initial twice at the 48 degrees the timing light would not know where the advance comes from it just sees the total result.