327-350 compression?

[Joe #39538]

I have a 67 with an original motor which is supposedly a stock 327/350. The engine runs smoothly but has little power. I have tuned it and checked carb and vacuum but to no avail.

I am going to do a compression test tomorrow. What should the compression be?

[Joe L.]

Re: 327-350 compression?

Joe----

I would say ABOUT 160 lbs. Even more important is that there is consistency among cylinder readings. More than 10%, or so, variation between cylinders can indicate a problem in the low cylinders.

Actually, a cylinder leak down test is a much better method for assessing the condition of an engine. Decent leak down gauges can be had for $75-100. With one of those and a compressor one can do a 1st class job of engine condition assessment.

If you do use a "popper" type compression tester, make sure that you use the type that has a short hose and fitting that screws into the spark plug hole. The type that you have to hold into the spark plug hole while cranking the engine are WAY too unreliable and they're also a pain to use.

[Roger Legge]

Re: 327-350 compression?

Make sure the carb is held open so it is not a restriction to incoming air.

Roger