how do you get to 0 degress TDC?
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how do you get to 0 degress TDC?
A buddy is facing a dilemma and needs to find ZERO degrees TDC to set his PFC.
Can anyone shed light on this?
Thanks.STYX.
Can anyone shed light on this?
Thanks.STYX.
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If the lead coil timing is 5 degrees ATDC when the notch and pin line up, advance your timing light 5 degrees and take note of the distance between the notch and the pin. After stopping the engine, set the notch to that point.
I'm no expert, but it's the only method that comes to my mind.
I'm no expert, but it's the only method that comes to my mind.
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There is a write up around here somewhere. From what I recall, TDC occurred when an apex was halfway between the leading and trailing holes. Pull spark plugs, get a mirror (Canadian Tire has had those snake cameras on sale every once in a while, would work excellent for this). Apex is in trailing hole, mark pulley. Spin engine until apex is in leading hole, mark pulley. Back engine up, halfway between your marks. I believe that gets you very close.
#4
There is a write up around here somewhere. From what I recall, TDC occurred when an apex was halfway between the leading and trailing holes. Pull spark plugs, get a mirror (Canadian Tire has had those snake cameras on sale every once in a while, would work excellent for this). Apex is in trailing hole, mark pulley. Spin engine until apex is in leading hole, mark pulley. Back engine up, halfway between your marks. I believe that gets you very close.
I'd suggest swapping the pulley for stock one or a more accurate racing beat one. Confirming timing and then transferring the timing marks to whatever pulley they are using. Is there any reason this wouldn't be an option?
#5
You could even rotate the engine a few times, and recheck it at the 5 and 20 mark.
Edit: now that i think about it, this may or may not work
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#6
If you trust your stock timing marks (the pulley and hub were never switched around between engines), use the stock -5 BTDC/+5 ATDC leading mark. This mark was created during the manufacturing process. It's better than anything you can do screwing around in your garage with a sharpie. The reason for this is because a bad timing mark would affect emissions.
There are a couple methods for setting this in the PFC. Here's one that can be done easily using just the Commander.
1) Install the crank angle sensor just like you would on the stock ECU. Follow the service manual procedure and search the gazillion threads about it. HAILERS has written extensively about installing it. If you got it on the correct tooth, the engine should at least start unless something else is wrong.
2) Go into your Commander's etc. --> Function select screen. Turn off "IDL IG Control" . If you have the old Gameboy-looking green Commander, there should be a funny Japanese character to indicate that it is OFF.
3) Start the Engine.
4) Go to the monitor screen--4 channel. Select RPM, IGL, IGT, and Water Temp.
5) When water temperature exceeds 60C, verify that your IGL = -5 and IGT = -20 . Turning off "Idle IG control" locks the timing at this setting as long as you don't have other loads coming on. You might be able to bring the Commander out into the engine bay to look at.
7.
![](https://www.rx7club.com/attachments/2nd-generation-specific-1986-1992-17/465199d1337301012-how-do-you-get-0-degress-tdc-timinglight.jpg)
I just check the leading side...
8. Put IDL IG control back on if you plan on using that feature.
9. Done
There are a couple methods for setting this in the PFC. Here's one that can be done easily using just the Commander.
1) Install the crank angle sensor just like you would on the stock ECU. Follow the service manual procedure and search the gazillion threads about it. HAILERS has written extensively about installing it. If you got it on the correct tooth, the engine should at least start unless something else is wrong.
2) Go into your Commander's etc. --> Function select screen. Turn off "IDL IG Control" . If you have the old Gameboy-looking green Commander, there should be a funny Japanese character to indicate that it is OFF.
3) Start the Engine.
4) Go to the monitor screen--4 channel. Select RPM, IGL, IGT, and Water Temp.
5) When water temperature exceeds 60C, verify that your IGL = -5 and IGT = -20 . Turning off "Idle IG control" locks the timing at this setting as long as you don't have other loads coming on. You might be able to bring the Commander out into the engine bay to look at.
7.
![](https://www.rx7club.com/attachments/2nd-generation-specific-1986-1992-17/465199d1337301012-how-do-you-get-0-degress-tdc-timinglight.jpg)
I just check the leading side...
8. Put IDL IG control back on if you plan on using that feature.
9. Done
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