Can someone explain timing procedures to me?

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sharpie

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Can someone break down timing an engine (specifically a 5.9 Magnum) to something I can understand? I'm kind of stupid about this stuff.

I thought I understood timing, but I realized that much of my engine's issues could stem from bad timing and too much/little advance, so I would like to retime it correctly.

Assume I'm starting from scratch here. Assume my cam is degreed, but assume my balancer has no timing tape on it. I have timing tape to put on it, so if you could tell me how to correctly install it as well, that would be awesome.

I should have the tools:

Timing light
Vacuum gauge
Dwell tach
In-car tach
various hand tools to change distributor position and vacuum advance position

I just really don't know whether what I did prior was correct. Thanks in advance. Sometimes it seems I just need a simple explanation and I understand the subject a whole bunch more.
 
To install your timing tape you could do this. With the engine assembled you could make a piston stop from an old spark plug. Break the ceramic off and drill it out. Weld on a 5/16" nut where the ceramic was and use about a 3" 5/16" with another nut to lock it down. I would round off the end of the bolt so I does not dent the top of the piston. Install the bolt about 1" down in the #1 cylinder and lock it down. I would pull all of the spark plugs to make it easier to turn over by hand Do Not use the starter. Turn the engine clock wise slowly until it touches the stop. Make a mark on your balancer and cover. Then turn the engine counter clockwise until it hits the top again turn it back clockwise just to take up the timing chain slack and make another mark. Split the difference and that will get you pretty close to Top Dead Center and you could install your timing tape and will give you somewhere to work from.

Remove the piston stop and replace all plugs. From that point you will need an advance timing light. Disconnect the vacuum advance from the dist and plug it. Hook up the timing light to the #1 cylinder. Now you can set your base timing. If you have any cam at all your base timing will be around 15 degrees advanced while the engine is idleing. That will give you a good starting point.

piston stop.jpg
 
Search around here there are a bunch of threads on how to time a street car.

max out initial the starter will handle, no run on, or use a vacuum gauge. Then limit distributor mechanical to desired total... it's that simple.

Then you can mess with the advance springs to speed up the curve.

A thread that has a good way to mark the balancer and you don't need a timing tape... they usually fall off anyways.

http://www.forabodiesonly.com/mopar/showthread.php?t=80613

search for FABO threads. I've answered a bunch about of how to time a car using a vacuum gauge. Member "Shane" started one. Read those and you'll get a better idea.
 
I don't quite get what "desired total" is. I also don't know what I would look at to find the total timing vs. mechanical timing. Like I said, assume I'm a real idiot (because I am)
 
Can you post your combo? Be detailed. The engine, trans, gearing, car, fuel type, and where you live...
There are a bunch of different ideas on how to get things "right". So I figured I'd go over mine but I need more info.
 
Awesome! Here's my combo:

1971 Demon
TF904 (torque converter definitely not optimal)
2.76 7.25" rear end (upgrading to a 2.94 8.75" soon)
fuel type 91 octane
Live in the central valley of California - hot summers, freezing winters

As for the engine:

1998 5.9 Magnum
4.030" bore
3.58" stroke
ProTopLine/RHS heads 1.88/1.6 valves
Stock 1.6:1 Magnum rockers
Stock Magnum lifters
Stock Magnum pushrods
STL-H405CP30 pistons with +10.00cc piston dome volume
Hughes Engines HER1418ALN .520"/.544" lift; 214/218 degrees @ .050" duration; 108 degree LSA
MP "orange" electronic ignition with MP electronic distributor (w. vac advance)
Edelbrock dual-plane RPM Air-Gap intake manifold
Hooker Comp headers
Bouchillon Performance harmonic balancer/5.9 flexplate/neutrally balanced torque converter
 
16 initial
18 in the distributor
34 total all in by 2200-2500

Read the doc file the one guy posted in that other timing thread you posted in today. It lays out what to do in pretty good detail and explains the terms.
 
You sont say what stall the convertor is but I'll assume its a stocker. Running some quick numbers I see a small cam and a lower static compression with a low stall and no gear. I'm not sure if you're chasing a problem, but I'd go like this. The base timing should be high/ Base timing is your initial. That;s what is set by turning the distributor at idle, with the vacuum disconnected and the carb line plugged. I would set that at 18°, with the idle speed set to 750rpm. The next part of the system is the total advance which includes the centrifical advance in the distributor. On MPs, you set the centrifical amount by adjusting the set screws down in the body of the distributor under the pickup plate. You test by using the timing tape or a timing light with the advance function. Slowly raise the rpm in park until the timing mark stop advancing.. Usually around 3500 rpm Record what the tape says in terms of degrees... You will want to subtract the 18° from it, and that is what you have for centrifical now... I'd guess it will be something like 25°. you'll have to re-set the screws so it only advances about 20° so you end up with 38° total. Get those set, then reset the carb's idle speed and mixture. Then we can start on the vacuum advance setup.
 
I will do that! I went through a couple things tonight, and picked up some new spark plugs. I am going to set timing tomorrow.
 
crackedback said:
16 initial
18 in the distributor
34 total all in by 2200-2500

Read the doc file the one guy posted in that other timing thread you posted in today. It lays out what to do in pretty good detail and explains the terms.
Click to expand...


I just wanted to come back and update and thank everyone. I put the light on my engine - I was at 35° BTDC initial. I am an idiot. I brought it back to 16° initial and it began running like a freaking champion. I stuck the distributor back in after dialing in my carb, and I my advance comes in WAY before I want it to, so I am going to have to mess with my distributor. I think it comes all-in about 2500 RPM, boosting it up to 37-38 total. If I can bring it in another 5-6 degrees, I think it'll be happy. At 2K right now, I am getting some light pinging.

But I want to thank everyone for their help. It has really motivated me on the car - as it's finally running reliably. Thanks again!
 
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