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Discussion Starter #21
Have retarded the Exhaust to about 101 102 and there's a noticeable increase in power (nice) and the rear exhaust "popping" isn't as pronounced as it was. Before the test drive I also exchanged the 50 F9 with 55 F8 as they are the only spares I have .... do you think I should still get the 50 F8 as you suggest ?
I have a feeling that the light is betting brighter at the end of the tunnel !
 

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Discussion Starter #22
Timing chains don't stretch much and the adjuster is used to take up the slack. Take a picture of it and post it and let the experts give their opinions on whether you are getting ready for a replacement. If you do replace it, do not buy the cheapest one you can find. Their are some poor quality chains out there.
Having said that, the story of a slack chain causing misfires/spitting back is a new one on me.
Here's a pic of my timing chain in situ' - tell me what you think from what you see .... No links look worn and no sign of oxidation anywhere.
 

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It is not possible to see the amount of extension of the adjuster in your picture.
 

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I have the same carbs on my car, I had the same spit back issue. My problem in the end was from the carb jetting themselves, I switched E tubes from F9 to F16 and my problem stopped. I highly doubt your timing chain is the problem for this issue.
After switching up the jetting you will probably have to lean out the carbs a little, I did. Just follow the plug color.

Follow Richard and Ed's advice and you'll have a happy Alfa soon, they got my Weber issues sorted.
Set cams at 104/104, recheck and adjust jetting
 

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Discussion Starter #25
20200428_115316.jpg

Here is a picture showing my chain tensioner - It's hard to measure so I'm estimating its open about 7-8mm
The chain feels tight with a little play between cams (up and down about 3-4mm) .
I also checked my valve clearances and found the following
Intake 1) 0.41 2) 0.49 3) 0.42 4) 0.43
Exh 1) 0.45 2) 0.51 3) 0.45 4) 0.45

Looks like #2 is just outside the ranges for both in and out is this acceptable ?
 

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Discussion Starter #26
Timing chains don't stretch much and the adjuster is used to take up the slack. Take a picture of it and post it and let the experts give their opinions on whether you are getting ready for a replacement. If you do replace it, do not buy the cheapest one you can find. Their are some poor quality chains out there.
Having said that, the story of a slack chain causing misfires/spitting back is a new one on me.
Ed
I have decided to change both Cams and the Timing chain. Can you recommend a good quality chain brand please.
Been checking the cars service history and there is no record of the chain being changed so I think 40 years and 100k miles + It's due for a change.

Thanks
 

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IWIS or Regina chain
 

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Discussion Starter #29
IWIS or Regina chain
Decided to replace both Cams, - what do you recommend for both inlet and exhaust ?
Brief summary of car ... 81 Spider , pair DCOE40 -151, Electronic Ignition.
Will replace all the Tappets as well.
Thanks in advance .
 

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Research the posts in the past couple of years about tappets before you decide to buy new ones. The news is not all good.
 

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Discussion Starter #31
OK, "Here's the thing": (I learned that from one of the guys running to be our president)
We would do better getting you going if we had a bit more information.
1. What model carb. are you using. 40DCOE XX
2. Did you just have them worked on and have just mounted them?
3. How did you sync the carbs?
4. I don't understand your procedure using the strobe light. If you could see the cam
marks using a strobe light you must have a good coating of oil just about every where.
Now you could do that if you had a clear plastic valve cover.
5. Lastly and most importantly (according to Click and Clack ) what is the color of the car?
Richard

I am going to purchase two new Cams to replace the two warn ones I have on the car.
Within my budget I have a choice of an 11.1 , 10.9 or 10.5 from either Alfaholics or Centreline.
The 11.1 fits without a Head modification and was advised it would be best to fit on the Inlet side and the 10.5 on the Exhaust side. I have also been told that fitting 10.9 on both sides would not cause a problem either.
What is your opinion on this ?
Thanks in advance
Colin
 
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