1970 Chrysler 383 Compression?

NWPT70

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What is the acceptable range of good compression on these engines (Chrysler 383) ?
 
Are you asking how low can your compression go before you should address an old engine?
 
From your question you must have a 383, so what compression no's do you have? From that we can tell if you need to be worried or not.
 
I have worked on a number of them with 70-75 on all eight. Smooth of course at an idle, as the difference between the eight is zero. However, no power under a load. 115-135 is ideal hot.
 
That doesn't seem too bad, especially as they are the same. If you had 90 in 7, and 35 in another, you'd have a serious mis-fire going on. The motor is till tired, but unless you're planning on running some quarter miles, it should still serve you for a good while.
 
That doesn't seem too bad, especially as they are the same. If you had 90 in 7, and 35 in another, you'd have a serious mis-fire going on. The motor is till tired, but unless you're planning on running some quarter miles, it should still serve you for a good while.
Which brings me back to my original statement "when it becomes embarrassing to drive up a hill".

Alan
 
I am really surprised it runs, if you put some oil in the cyl does the no come up? If so the rings are worn. I would plan on a rebuild soon.
 
With that compression test.

Does it do what you want it to do right now without smoking? If so, run it.

Does it smoke or do you plan on any performance additions? Rebuild it.
 
With that compression test.

Does it do what you want it to do right now without smoking? If so, run it.

Does it smoke or do you plan on any performance additions? Rebuild it.
I plan to just run it. It does not smoke at all and still runs smooth. I will plan to rebuilt the engine in the future but for now I will let it ride as is.
 
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