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kenikh kenikh is offline
3 restos WIP = psycho
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Join Date: Feb 2005
Location: North of Exit 17
Posts: 7,729
Originally Posted by 911st View Post
If you were effectively a twin plug on 5 cylinders and a single plug for one and it was properly timed for a twin plug it would probably detonate a bunch on the single plug cylinder.

That is one of the challenges of a twin. I think a number of people lost 3.6 motors to detonation when the belt that drove the second rotor failed.

Might want to check you injectors and do a balance test to be sure you do not have a cylinder or two running lean. I do not know if it is just the lighting but on the header pic it looks like the two center cylinders might be running lean.
This is one driver on why I am going to run knock control. One, you get some margin, two knock gets logged, so if the EMS sees a single cylinder banging its brains out, you know it.

Even with knock control, many a 3.6 went TU due to the "ozonated belt" issue in the 964 distributors killing the second plug bank. I am not sure if the CEL on these cars was set to notify owners there was an issue.

This risk comes with the territory, I guess.

- 1965 911
- 1969 911S
- 1980 911SC Targa
- 1979 930
Old 06-11-2010, 09:07 AM
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