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Difference between Low Compression & HC red motors
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What is the difference between Low Compression and High Compression red motors. Did holden produce the compression difference using different pistons or different heads or some other means?
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The difference is in the head. It is quite easy to tell them apart on a 6 cyl...look at the passenger's side of the head near the back and there will be a circle cast into the head with an L or an H in it. The L stands for Low compression and the H for hi
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On the 186 motors the Engine Plate will also indicate wether your motor is hi or lo comp.
Now a manual or something will tell you for sure, as I am going off my memory which can fail me occasionally, but I think it was thus:
The 186P was the low c
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Hi Guys.
That is only partially true.
The low comp versions of the smaller motors where made, simply by using head of the larger motor,
i.e. a 149 lo comp has a 179 head, a 161 lo comp has a 186 head & a 173 lo comp has a 202 head.
A lo comp v |
If at first you don't succeed, just call it Version 1.0 |
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Also the low compression heads have a largw combustion chamber the high compression have half the camber filled in.
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Yes johnperth, but that is only true for the smaller motors. All the 179/186 & 202 hi comp motors also have the larger combustion chamber.
Dr Terry. |
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I never knew about that until I just read this thread, so ,I`ve just checked my engine and it turns out its a low comp. head, can I just put a high comp. head on it or is there more to it than that? does anything else need ro be changed as well? and also
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Hi ToddBrokenHill.
You are confusing the issue by calling them lo & hi comp head.
You are better off referring to them as large chamber & small chamber heads. It depends what block they are fitted to before you know what compression you will end up |
If at first you don't succeed, just call it Version 1.0 |
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Difference between Low Compression & HC red motors
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