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Opel Rallier since 1977
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LOL.... good one. I think she is on to you and your shenanigans....

I am of mixed feelings on the HF gun..... a straight forward timing gun is pretty darned simple so I guess the HF one would be OK. You just never know on their stuff...

Now the limitation of that type of gun on these particular cars is that you can only see the BB lined up with the pointer in the engine flange when you are at stock timing.... which as you now know is for emission, nor performance. When you adjust the idle timing (called 'initial' timing), the BB disappears out of the 'window'; same thing ahppnes when you try to measure the mechanical advance vs RPM. So to use that simple type of gun to change the timing or see how far it is off of stock timing or how much it changes with RPM, you need to make a new set of degree marks on the pulley to view agasint the cast-in marks on the timing cover (easiest) or the flywheel (not so easy). In V8-land, there are items called timing tapes that are applied to a front damper/pulley at the front of a crankshaft. Here is what a comprehensive set of timing marks with a timing tape looks like and how to install them on a V damper/balancer. You can use these principles to establish timing marks on the front pulley of your Opel and reference them to a fixed mark on the timing cover.

If you don't want to add any timing marks, and you want to set timing other than stock timing, then you'll need a so-called 'dial-back' timing light. like dpre has. If the timing is not stock so that the BB is right by the pointer, then you use the timing gun and slowly adjust the dial until the BB does come into to alignment with the pointer. That is your true timing. And once you really know the true TDC (top dead center of #1 piston's motion in it cylinder), you can just put a mark on the front crank pulley right beside the cast-in mark on the timing cover and you won't have to mess with seeing the BB anymore.

Just be aware that dial-back timing lights often have problems with multi-spark discharge types of ignition systems. But your Hotspark # 3BOS4U1 does not look like it is one of those. I always use a standard timing light and establish timing marks on the pulley or somewhere.

Hope that helps more than hurts.;....
 

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Thank you Mr.Manta
I think I understand that so once cylinder 1 is TDC does it matter where I make a mark on pulley and cover ( 9 oclock 12,3,ect) as long as they are in line to each other
 

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Opel Rallier since 1977
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1,035 Posts
You are 100% correct Terry. Get that #1 TDC mark established pulley to wherever; many (most?) of the stock AL timing covers have a cast in mark at about 1 o'clock above the pulley when viewed from the front. The 'wherever' can even be a homemade, sturdy pointer that bolts to the timing cover (and ends up in the same place when you R&R it). Below is a pix of one I made for a 340; the '0' mark on the silver bracket for #1 TDC when lined up with the notch in the damper ring. I added a timing tape (like in the video) after this pix for a wide range of timing visibility.

Then mark the pulley in at least 5 and 10 degree increments. If you take the crank bolt out, then you can pull the pulley off. (Careful, it is a bit flimsey, so don't pry on it with a big screwdriver.) Then sit it down and make some accurate angle/degree marks like the video shows of the timing tape. You want to go 10 degrees CCW
and 50 degrees CW from your 0 mark.

DSCN1756.JPG
 

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Be sure to post in the Transmission group.
 

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Have you checked to make sure the mechanical timing advance is working properly?

Harold

P.S. I haven't read all of the posts, so my apologies if it's already been stated or someone else has already suggested that you check the mechanical advance.
 
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