I have a 71 swinger with a 360. the car runs strong at about 35 deg timing. The only problem problem is it kicks back when you start it. I'm afraid ill strip the starter or flex plate. who makes something to retard the timing while starting then advance it for driving Thanks Jim
timing woes
- Thread starter sorewrist1
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What have you set the initial timing to? I guess you are running 10 initial/advance and getting 24-25 from the weights? Not running the aftermarket limiter plate (34 total)? If you are happy with the total, you can reduce the initial a couple degrees then allow the weights to move further.
There are electronic controls where you rotate a distributor with no advance mechanism to the total and lock it down, then the box retards for cranking and less and less as the rpm increases.
There are electronic controls where you rotate a distributor with no advance mechanism to the total and lock it down, then the box retards for cranking and less and less as the rpm increases.
Is it locked out at 35, then yeah that might be an issue. If the distributor has a curve in it then you need to know the idle timing and total number/RPM.
Bad battery cables/poor ground can cause plenty of starting issues as well
Bad battery cables/poor ground can cause plenty of starting issues as well
I just bring to 3 g and set it at 35
It's an electronic ignition
You need to see what the initial (idle) timing is. It's likely too much.
If I time it so it starts easy it has no power
I'll check it tomorrow at idle. Vacuum disconected
Make sure to plug the advance hose coming from the carburetor, too. . If we can get what the idle timing is, we can better help.
Newbomb Turk
Well-Known Member
That’s because you don’t have the correct curve in it. I’ve posted this so much I’m sick of it but here goes.
99% of these engines want a curve. I doubt you are in the 1% group so don’t lock it out.
That’s a quick way to kill power around peak torque and it’s probably killing max hp too depending shift rpm.
That is because around peak torque, which is your highest volumetric efficiency these engines want much less timing there.
Let’s say you have it locked out at 35. Rule one is at let’s say 6k you won’t have 35 degrees. Why is that?
Because every ignition system out there except points WILL retard the timing. I guarantee it. That is caused by the slew rate of the internal switches and such.
Just like it takes time to open and close the points, it takes time to turn off and on the switches. That’s skew rate.
They all do it. What rpm and how much is only known by checking the entire ignition as it runs in the car on a distributor test bench. Once you do that you can correct the curve to account for the retard.
Or you can set your total timing at your max rpm. Then you’d know the exact timing at that rpm. What your timing is at lower rpm is anyone’s guess. But you can bet it’s a curve because of the retarding.
One of my favorite (I HATE DOING IT) things to do is get the curve right with an over cammed, low compression.
That’s because it will want as ASSLOAD of initial timing, almost nothing more at peak timing and then it wants a creeping curve until max rpm. Getting that is a *****.
Nothing you can do can account for your retard. ;)
Scody21
Just send it
A helmet might help though….
MOPAROFFICIAL
Oogliboogli
Like everyone is saying..
The initial timing is the reason for the kick back... lower that alone by maybe 2 or 3 degrees and see if it still back back.
What brand distributor is in it?
What compression ratio and camshaft is being used?
The initial timing is the reason for the kick back... lower that alone by maybe 2 or 3 degrees and see if it still back back.
What brand distributor is in it?
What compression ratio and camshaft is being used?
If you have found by experimentation that engine performance is best with 35*, & you get no detonation, then keep it there. For easy starting, there are two simple options:
- a switch under the dash that grounds one side of the pick up [ p/up has two wires, does not matter which wire you ground ]. For starting, have the sw in the ground position, as the engine cranks, flick the switch to remove the grd & the engine will start.
- use an adjustable vac unit connected to manifold vacuum [ MVA]. This adds timing at idle & cruise. As an example, select 15* initial & add 20* with MVA. The 35* can be any combination of initial + MVA that gives 35*. On the VA unit, screw the Allen Key fully CW. You may have to make a stop for the VA actuator to limit total travel.
- a switch under the dash that grounds one side of the pick up [ p/up has two wires, does not matter which wire you ground ]. For starting, have the sw in the ground position, as the engine cranks, flick the switch to remove the grd & the engine will start.
- use an adjustable vac unit connected to manifold vacuum [ MVA]. This adds timing at idle & cruise. As an example, select 15* initial & add 20* with MVA. The 35* can be any combination of initial + MVA that gives 35*. On the VA unit, screw the Allen Key fully CW. You may have to make a stop for the VA actuator to limit total travel.
I think your weights are advancing more than 35 deg by 3k. I suggest installing a limiter plate with the 10 or 12 slot over the round pins then time it again at 3k. Might clean and very lightly lube the pins and pads while you are in there.
MadScientistMat
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Keeping the timing low at idle and bringing it up to 35 at high RPM is the mechanical advance's job. Check to be sure that's working.
sorry guys I broke my starter . Ill have to get back with you when i put a new starter in. I appreciate all the helpful info.
Damn, sorry to read. I would say it's way too far advanced if it's killing starters.
thanks i have to pull the distributor out and see if it has a mechanical advance
Should be able to tell by Just pulling the cap. Look for springs/weights.
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