identifying an H.C. head, How?

[Terry, NJ]

On one of my coupes, I have a indistinguishable looking head. It runs pretty good so I'm suspicious that someone put a HC head on it. But I don't know. Do the after market manufacturers use some sort of marking system so their heads can be identified at a later date? The engine runs fine so I don't want to rip it down at this time.
Terry

[steve s]

Check the compression.

[Charlie Stephens]

Take some photos especially any markings on the head and post them. Maybe someone will recognize something. You could also find out by running a compression test.

Charlie Stephens

[James Rogers]

Stock heads from Ford have a tiny bump just above the water pump below the water outlet. Snyder heads have 2 bumps on the driver side with 5 small pin pricks in each. Brumfield heads are marked with a B-F. Ford police heads have a large B or C cast in them. Other than that all bets are off and you will have to remove the head and check the combustion chamber. I have seen heads with several different names cast in them such as the lion head and a Hoof head I have. There are many aluminum heads with varying compression ratios such as the Thomas and cyclone heads among many others.

[Anteek29]

So, what is the expected compression for a stock head?

[Terry, NJ]

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14.7 (one atmosphere) X 4.2 = About 60lbs, But you have to add some for the heat generated during compression, so about 65 lbs with good rings and valves. However, What's the compression of a, say a 5.5 CR head , By my calculations, it will be around 75- 80 Lbs. Your compression may vary! Temperature, humidity altitude, and probably cranking speed, all of these will vary from day to day.
Terry

Originally Posted by Anteek29

So, what is the expected compression for a stock head?

[29er]

Originally Posted by Terry, NJ

14.7 (one atmosphere) X 4.2 = About 60lbs, But you have to add some for the heat generated during compression, so about 65 lbs with good rings and valves. However, What's the compression of a, say a 5.5 CR head , By my calculations, it will be around 75- 80 Lbs. Your compression may vary! Temperature, humidity altitude, and probably cranking speed, all of these will vary from day to day.
Terry

I installed a new Snyder 5.5:1 head last August in my '29er. A compression test then resulted in 75# plus/minus 1# for each cylinder.

Mike in Orygun