Question about setting initial timing on 5.9 Magnum

[jcwren]

I've replaced the heads on my 5.9 Magnum, and am reinstalling the distributor and oil pump drive gear. When dropping in the drive gear, I can set it so that the tip of the distributor is pointing roughly between cylinders #1 and #3 or pointing between slightly past #1 and the water pump. Adjusting the timing will make either work, but what is the "correct" way when people say "pointing at #1"? I know I'm at TDC on the compression stroke and that the harmonic balancer timing marks are correct based on the timing before removing the heads.

Thanks!

 

[TT5.9mag]

Drop the gear in with the slot pointing to the front most intake bolt on the number 1 side. Set the balancer marks to line up with 30 degrees before TDC on the pointer. The drop the distributor in with the leading edge of the rotor pointing to the leading edge of the number 1 terminal on the cap. That’ll get it to fire right off. If your balancer isn’t marked, mark it.

 

[jcwren]

Drop the gear in with the slot pointing to the front most intake bolt on the number 1 side. Set the balancer marks to line up with 30 degrees before TDC on the pointer. The drop the distributor in with the leading edge of the rotor pointing to the leading edge of the number 1 terminal on the cap. That’ll get it to fire right off. If your balancer isn’t marked, mark it.

Thanks! What book or document is that picture from?

 

[TT5.9mag]

Thanks! What book or document is that picture from?

The google machine.

 

[TT5.9mag]

That image has been floating around here for a very long time. I’m not sure where it originates from.

 

[crackedback]

make sure the distributor tang is sort of inline with the rotor tip

Some distributors, MSD, have the tang perpindicular to the rotor tip and the drive gear needs adjusting

 

[67Dart273]

That image has been floating around here for a very long time. I’m not sure where it originates from.

It's a sort of copycat of what were in the service manuals for a long time. Prolly came from a Clymer's or some such

To be clear ARE WE talking about a Magnum that has been converted to carb and conventional ignition AND NOT the OEM computer?

So far as "not by the book" and as cracked back pointed out, there are differences in dist tang to rotor orientation, you can actually close your eyes and just toss the shaft in there. AND you can just close your eyes and just toss the distributor in after it.

Stick your finger in no1, bump the engine until you feel compression. Continue to bump/ wrench the engine until the marks start to appear. DO NOT stop on TDC, but rather where you want the initial timing. Now look at the dist. Rotate it retard, AKA CW for a SB/ magnum, and then rotate slowly CCW until the pickup and reluctor are aligned. Plug no1 in whereever the rotor is pointing. It will run and you can time it just fine.

If the vacuum advance interferes, try rotating the distributor so the rotor moves "one hole" and then rotate the plug wires on hole, or else rotate the dist gear a tooth. You can walk it up and out with a screwdriver in the slot

The point is this will work and it will run. You can do it "by the book" if you want.

Here is the shot out of section 9 of the 74 chassis service manual

 

[rbkt65]

there is also a tsb about replacing the dist bushing and intermediate shaft then resetting the timing. tsb is 18-16-92 revision a.

 

[jcwren]

It's a sort of copycat of what were in the service manuals for a long time. Prolly came from a Clymer's or some such

To be clear ARE WE talking about a Magnum that has been converted to carb and conventional ignition AND NOT the OEM computer?

So far as "not by the book" and as cracked back pointed out, there are differences in dist tang to rotor orientation, you can actually close your eyes and just toss the shaft in there. AND you can just close your eyes and just toss the distributor in after it.

Stick your finger in no1, bump the engine until you feel compression. Continue to bump/ wrench the engine until the marks start to appear. DO NOT stop on TDC, but rather where you want the initial timing. Now look at the dist. Rotate it retard, AKA CW for a SB/ magnum, and then rotate slowly CCW until the pickup and reluctor are aligned. Plug no1 in whereever the rotor is pointing. It will run and you can time it just fine.

If the vacuum advance interferes, try rotating the distributor so the rotor moves "one hole" and then rotate the plug wires on hole, or else rotate the dist gear a tooth. You can walk it up and out with a screwdriver in the slot

The point is this will work and it will run. You can do it "by the book" if you want.

Here is the shot out of section 9 of the 74 chassis service manual

Yah, this is a 5.9 converted to carb (Quick Fuel Brawler 750 CFM 4-Barrel) on an Edlebrock 7577 dual plane intake with a MSD 5834 distributor and MSD 5520 box. Indeed, the tang and the distributor tip are 90 degrees out from each other.

Any suggestions for recommended initial timing? I see 10-12 BTDC in most places, but also see 5 in a few places. The distributor I >think< has the red bump stop, giving 28 degrees of advance. It's got two silver springs, but I don't know if they're the light or heavy ones, so it's either set up for the slowest or fastest advance. When I bought this '67 Barracuda it had this engine in it, but I don't have the additional bump stops or springs to compare these to. It does not have the vacuum advance pod.

 

[TT5.9mag]

Yah, this is a 5.9 converted to carb (Quick Fuel Brawler 750 CFM 4-Barrel) on an Edlebrock 7577 dual plane intake with a MSD 5834 distributor and MSD 5520 box. Indeed, the tang and the distributor tip are 90 degrees out from each other.

Any suggestions for recommended initial timing? I see 10-12 BTDC in most places, but also see 5 in a few places. The distributor I >think< has the red bump stop, giving 28 degrees of advance. It's got two silver springs, but I don't know if they're the light or heavy ones, so it's either set up for the slowest or fastest advance. When I bought this '67 Barracuda it had this engine in it, but I don't have the additional bump stops or springs to compare these to. It does not have the vacuum advance pod.

View attachment 1716444565

Shoot your timing light at the balancer and rev the engine (in neutral) up until the distributor stops advancing. At that rpm set the timing to 33 degrees. Thats where Ive found the magnum head stops making more power with more timing. Some say 34 but I haven’t seen that. Mine is currently idling with 17 degrees initial with a 218 @050 cam and I’m using a pcv valve for bypass air. 17 degrees is what it wanted to keep the transfer slots on the primary throttles square. You are likely going to have to limit the mechanical advance inside the distributor to get those kind of numbers but it’ll be worth it.

Edited to add;
This is all done with the vacuum advance unhooked and plugged at the carb.

 

[Frankbassman]

My 2 cents for reference.

I have a '97 5.9 magnum converted to carb.

Stock everything else including cam!

It wanted 32 degrees max timing, and idled best at around 20 degrees.

Lucky for me I had a mid 80s van distributor that only had about 12 degrees of advance in it, and setting it at 20 idle gets me to 32 total, with stiff springs. (Perfect!)

I DO run vacuum advance. It has about 22 degrees of advance, which may be a little much. I adjusted the spring to have more tension to not have it throw all the advance in so aggressively at light throttle.

The engine has about 22 or 23 inches of vacuum at idle in neutral.


-Frank