Tdc?

Neelsonwheels

Neelsonwheels

Donating Member
So I recently checked my timing with my timing light. The ECM
was calling for 30 degrees of timing so I adjusted the dial on my light to
30 and was expecting to see the timing mark at zero. I did not.
I went into Bigstuff and locked out the timing at 25 and checked it with
My light same thing timing mark was not present at zero. So me being
Me I assume the balancer must have sipped. So I removed all the plugs
Pulled the dizzy cap and serp belt to check top dead center compression
On number one cylinder. I found TDC and the timing mark is right on the money
WTF. I did notice the the rotor was ever so slightly off from lining up
With the number one post of the cap. What am I missing here on syncing
The timing with Bigstuff? Or is my timing light crap?
 
Neelsonwheels

Neelsonwheels

Donating Member
Re: Tdc?

yep! If you lock the timing out a specific number in the Bigstuff3 program and check your timing on the balancer it should be the same. Bigstuff controls the timing. I have no advance mechanism in the Distributor at all. It is locked out.In the config. portion there is a Static test timing box that you can input a timing number and lock it at that value so you can then with
a light verify your timing is synced between the ECM and your distributor. Like I said TDC is dead on with the mark on the balancer. I will try to lock out the timing in the ECM at like 20 degrees tomorrow and check it with two different timing lights. Just to rule a bad light being the issue out.
 
Neelsonwheels

Neelsonwheels

Donating Member
Re: Tdc?

little update on this. I came to the conclusion my balencer had slipped. So i pulled it and lnstalled an ATI super dampner along with a new pointer. I then started the truck with my laptop hooked up to the bigstuff. I first noticed the AFR was high at idle 15.6. When i looked at the timing it was asking for 32 degrees so i broke out the light and checked it i was getting only 12 degrees per my light? i then loaded a previous tune from wrench fest and took it for a short ride. the truck feels like i am dragging a house! no power at all? I am at a loss. screw it time for a beer!!:rant::rant::rant:
 
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Quickstop [UK]

Quickstop [UK]

Combating adversyty.
Re: Tdc?

Rule out the light.

Disconnect the tan wire or whatever ot make it so BS3 isn't affecting the timing. Let it idle.

Set the timing light so the strobe goes off at 0. Advance or retardation as necessary. If it's a steady idle, should be able to advance or delay the strobe and see if the gun works. If the gun works, great. (It probably will)

IF BS3 is disabled, you should be able to get 0* with the gun and the dist. Can you?

Is this a new install of a dist? Is it a tooth off? (~40*)

Are you using the right plug wire for the crank trigger?

Is your new witness mark attached properly? Reading it right?
 
Neelsonwheels

Neelsonwheels

Donating Member
Re: Tdc?

Quickstop [UK] said:
Rule out the light.

Disconnect the tan wire or whatever ot make it so BS3 isn't affecting the timing. Let it idle.
i locked the timing out in Bigstuff.

Set the timing light so the strobe goes off at 0. Advance or retardation as necessary. If it's a steady idle, should be able to advance or delay the strobe and see if the gun works. If the gun works, great. (It probably will)

yep gun seems to work

IF BS3 is disabled, you should be able to get 0* with the gun and the dist. Can you?

not sure what you mean by this.

Is this a new install of a dist? Is it a tooth off? (~40*)

no the dizzy was not removed.

Are you using the right plug wire for the crank trigger?

yep number one,

Is your new witness mark attached properly? Reading it right?
Click to expand...

pretty sure. The balancer has a TDC mark at 0* and marks all the way around for 360*
 
Neelsonwheels

Neelsonwheels

Donating Member
Re: Tdc?

when I adjusted down from the 31* that I expected to see TDC the tdc mark didn't become visible until i dialed back to 12* on the light.
 
gringo76

gringo76

New member
Re: Tdc?

prob a dumb thought but the stock balancer has two lines on it that are fairly close to each other, is it poss you are looking at wrong line on balancer when timing it.
 
Neelsonwheels

Neelsonwheels

Donating Member
Re: Tdc?

I am starting to think that I have a wiring issue between the Bigstuff
And the distributor . Holly cow this truck is testing my patience!!!!
Should have bought a NA hot rod and just drove it. My wallet is very
Sore from this truck. WTF
 
Aeroking

Aeroking

e.i.
Re: Tdc?

something i noticed on mine. The distributor has 6 pickup points for the 6 cylinders, and the rotor only goes on one way... but the cam gear has an odd number of teeth. So depending on which way you put the cam gear on the distributor shaft, you could be half a tooth off, causeing a little bit of off-sync in the distributor.

Also, what is the crank ref angle, and inductive delay set to.

I had a problem with mine, where i picked a random number for my ref angle, and the ECM would not adjust timing below that point. I randomly picked 18deg, and even though my tune commanded less than 18deg, it would not pull the timing below that. so i switched it to 6..


If you verified TDC with a piston tool, and saw that it lined up with 0 on the balancer, and dist rotor. I would set the timing light for 30, and turn the distributor until everything matches BS3
 
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