What is the best way to set Timing on an 82 SC?

[Rodney Nelson]

Alright, I have done a million searches on Setting my Timing for my 82 SC. A lot of the searches pulled up information on setting the timing at 35 Degrees BTD and disconnecting the O2 sensor all together. So I have a couple of questions:

1. The attached picture shows my distributor with two vacuum lines, I assume that one is the advance and one is the retard. Which one is what?

2. Do I remove both of these vacuum lines or just one?

3. How do I determine what 35 Degrees BTD is?

4. Also, I need to buy a new Timing light my old one broke. What is up with the adjustable timing light where you set the timing that you want. How does that work and does anyone have any suggestions on the best one to buy?

Thanks for your help,

[emcon5]

Originally posted by Rodney Nelson
1. The attached picture shows my distributor with two vacuum lines, I assume that one is the advance and one is the retard. Which one is what?

I can't remember, but it doesn't really matter. Depending on how you set the timing, they will either both be connected, or both disconnected. If you want to find out which is which, disconnect them one at a time with the engine running. The one that makes the idle speed increase when you unplug it is retard.

2. Do I remove both of these vacuum lines or just one?

You unplug them both to set the timing if you follow the manual. If you are setting 35º total advance, leave them both on.

3. How do I determine what 35 Degrees BTD is?

I supose you could measure it, but an adjustable one is much easier. If you don't have one, you can wrap a piece of paper around the pully, and mark/measure the distance between the Z1 and 5º marks, and multilpy by 7.

4. Also, I need to buy a new Timing light my old one broke. What is up with the adjustable timing light where you set the timing that you want. How does that work and does anyone have any suggestions on the best one to buy?

I have the Craftsman version seen here, it has a knob on the end that you use to set the advance. If I had to do it over again, I would pony up a little extra $$ and get one like this, with a RMP display. If you unplug the vac hoses, you will need to reset the idle speed before you can set the idle, and the digital tach is handy for verifying advance curve.

Hope this helps,

Tom

[braddb_82SC]

I'm sure I'm not the best person on this board to answer these questions but I may be able to help a little as I also own an '82SC.

1. In your photo orange hose is advance, black is retard.

2. If you are shooting for 35 degrees TOTAL advance at 6000 RPM you should leave both hoses attached. The black (retard) hose will only have vacuum at idle anyway. You may need to detach both hoses to adjust timing at idle, depending on whose timing specs you are trying to match. I'm not an expert in this area.

3. Advance timing lights have a knob that allows you to dial in, say 35 deg. You would then see a flash as the TDC mark on the pully passes the reference mark on the engine when the engine is 35 degrees advanced. With a standard light you would have to mark the pully for 35 degrees.
I like the Sears light. It's about $60. I have not tried others.

[96conv]

After I take Bruce Anderson's tune-up class on Oct 11, I'll be able to help you out. Can you wait until then?

[speeder]

If the car is stock, (or even if it isn't, but has stock distributor), set the timing according to factory spec. Your car should have an emissions sticker on the inside of the deck lid, but if not, here is what it said: timing: 5deg. BTDC @ 900rpm, w/ vac lines disconnected and plugged. You can then re-connect the lines, reset the idle, and check for total advance w/ an advancing timing light. The factory spec for total advance is 24-29deg. BTDC w/ lines disconnected, so basically that is 30-35deg. BTDC w/ vac advance.

It's cool to check that distributor is advancing correctly, (and very important to the performance and general health of the motor), but timing should be set at idle on SCs so that it is correct in the lower RPMs, where the motors live most of the time in street driving. The factory gives a ~5deg. variance for total advance, (difference in individual dizzys?), but no variance, nada, zip, for idle spec. Don't try to outsmart them, you will lose.

Rodney, your car still has the original vacuum lines, (might be time to change them), they are actually red, (advance), and blue, (retard). Your picture shows them connected to the correct ports on the advance unit, most likely the other ends are connected to throttle body right as well. To set timing, you must disconnect and plug them, your idle will drop way down, you have to adjust it up to 900(+50) RPM, set timing at 5deg. BTDC, then re-connect them and set idle back to ~900. Good luck!

[Rodney Nelson]

Wow, thanks everyone for your replies this clears up everything, now it seems easy.

I think I will buy the timing light with the advance option.

I had no idea what to do with the vacuum lines thanks for outlineing it for me.

Seems pretty simple, disconnect both lines and plug, then set timing at 5 degrees BTD.

Then reconnect and check for total advance at 30-35 degrees at 6000 rpm.

Sounds great!

What about the vaccum lines? I will replace them it shouldn't be that hard right?

One last question, what about the O2 sensor, should I disconnect and then only reconnect during emissions testing?

Thanks for all of your help.

[Vipergrün]

I have found that 35 degrees max advance dictates to approx 10-12 degrees at idle. Be sure to retard the timing if you hear ANY detonation (pinging). In fact, I'd probably stay around 30 degrees max advance in those hot Tucson summers Also, if you run with the higher advance, you'll want to richen up the fuel mixture. This is bad for the O2 sensor (and Cat), so you may want to remove it and put in a plug and consider a cat bypass pipe. I believe Pelican sells them both.

Good luck!

-B