Info on cylinderhead problems

 
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Iwan Louwage



Joined: 09 Oct 1989
Posts: 6
Location: Belgium

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Hi everybody,

I was wondering if somebody could give me some info on the derby 4 1/4 cylinderhead problems. What are the problems with it, how to detect it and what the possible solutions are?

Many thanks,

Kind regards
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Christopher Carnley



Joined: 16 Nov 2007
Posts: 2746
Location: Yorkshire, United Kingdom

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Had you anything specific in mind apart from frost and heat cracks,severe corrosion, hard silting up between the copper stud tubes,causing overheating, along with hard silt in the cylinder block?
The turbulation of the combustion chambers led to many instances of end charge detonation,"pinking" and the lip ridge was removed. Although this reduced the compression ratio a little there was no reduction in performance.

I have a modern (multi-thou pound) Fiennes "cure all" alloy head waiting for the rest of the engine to be machined, so when I have a "minute", I will take some pictures of it.
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Iwan Louwage



Joined: 09 Oct 1989
Posts: 6
Location: Belgium

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So i can asume that a original cylinderhead which is still doing what it should be will still have problems?
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Christopher Carnley



Joined: 16 Nov 2007
Posts: 2746
Location: Yorkshire, United Kingdom

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Even with an LE series 4 1/4 litre car, there are no certainties until an inspection, at least, is made.
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Paul Spencer



Joined: 17 Feb 2003
Posts: 1088
Location: Oxfordshire, United Kingdom

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Aren't there enough problems with things not doing what they should without worrying about those that do?
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