Tune up questions

Drew20

Drew20

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I've done quite of bit of housekeeping type maintenance on the top end of my CSL. I now have compression test results of 176-186 psi (cold), which I think is ok? It's the original 3003cc block with a later '85 head, in case that makes a difference.
For ignition timing I've used 22degs btdc at 1800rpm (vac advance disconnected), as this is what I found in my Haynes. However I think I've got this wrong, and it should be 22 degs at 2500rpm for a d jet injection car. Is that right?
I found this link:

Plugs look good, the original injectors are freshly cleaned and refurbed. Valve gaps set to 0.3mm. For idling, I can either have it steady at 1000rpm or, if I try to adjust the idle screw to bring it down a bit, it starts to fluctuate, between 600-900 rpm. Above idle it pulls strongly and smooth. I've checked the usual spots for vac leaks, no sign of any...

I'll take it for a run tomorrow and reset the dizzy at 22degs at 2500rpm, but are there any other ideas on how to make it idle steady at, say 800rpm?
 
This might help. It was going in the next clear out image.jpg
 
Are you relying on your dash tach for your idle reading? They're not very accurate (mine is 100 rpm too high) and I would suggest using a timing light with built in digital tach, set it at 950 plus/minus a little whichever your engine likes
 
thanks for the replies, I will reset the idle speed back to 950, and then set the timing to 22 btdc at 2500rpm. That should make it a bit smoother

I don't have a tacho on my timing gun, but I instead use a tacho hooked up to the coil so that I can monitor rpms in the engine bay, instead of relying on the in-car instruments
 
Are you running the original distributor with trigger points? If so, the curve may be off after 45+ years of use, mine was. Replaced with a 123 distributor, yet keep the original as a back ip with points & condenser. Can tell the difference between the two. 123 is smooth, original pulses slightly.
 
good question, I'm not 100% sure what my ignition is. I'll stick a photo up. It defo doesn't have any points however, so it's not original.

I can't feel any play in the dizzy shaft however, and the timing gun shows a steady and clear mark on the vibration damper.
 

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