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Hi

I've just replaced my timing chain and tensioner etc on my 80 dhc (AC Delco dizzy). I have correctly lined up the jackshaft, distributor, camshaft and crankshaft timing marks, put it all back together and the timing is way out - off the scale, more than 20degs BTDC at about 1800 rpm. I cannot adjust the distributor to make up the discrepancy. I cannot understand why it should be out and have taking it all apart again to check I hadn't slipped a tooth on the jackshaft putting it back, but it all looks fine. The car was running ok before, might have been a little out on timing but negligible. Any ideas why?

 

And how to adjust - should I just slip the chain off again and realign the jackshaft (incorrectly) to accommodate it?

Cheers

Frank

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Just had second thoughts on this, having spoken with mate owning TR4 - he questioned whether >20degs BTDC at 1800 was that far out given modern fuels i.e. you'd expect it to be different to the timing requirements when out the factory running 4star. I don't know what it was before I did the job and have never set the timing on this car, so I wonder whether I might just have another issue causing the misfiring I got after putting it back together.

 

So in addition to any views on my original post, can I also ask what people have found are typical static and/or dynamic timing settings for their standard 2.0L 8 valve engine? The manual says 10degs static, and 11, 15.7 and 20 degs dynamic at 1000, 1800 and 2400 revs respectively.

 

Thanks!

Frank

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Just had second thoughts on this, having spoken with mate owning TR4 - he questioned whether >20degs BTDC at 1800 was that far out given modern fuels i.e. you'd expect it to be different to the timing requirements when out the factory running 4star. I don't know what it was before I did the job and have never set the timing on this car, so I wonder whether I might just have another issue causing the misfiring I got after putting it back together.

 

So in addition to any views on my original post, can I also ask what people have found are typical static and/or dynamic timing settings for their standard 2.0L 8 valve engine? The manual says 10degs static, and 11, 15.7 and 20 degs dynamic at 1000, 1800 and 2400 revs respectively.

 

Thanks!

Frank

Check the manual carefully. I think you need to add the 10 static to the dynamic degrees, That gives 30 BTDC at 2400, which sounds about right to me.

Peter

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Thanks Peter.

You're right, and timing was a complete red herring, it's running ok now.

I opened up the distributor to check the advance/retard mechanism wasn't an issue and I noticed I'd somehow managed to knock off the condenser lead. One thing led to another, as it does... Still, I've learnt a bit I guess.

Frank

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