My 72 350 problems

I asked this once already but I have time tommorow to tinker I have low compression in one cylinder of my 72 350 2 bbl how can I diagnose the problem on what might be wrong and in the head is the problem can I use the head(s) off a 70 350 2bbl

 

Spray some oil into the cylinder through the spark plug hole, then test the compression again, if its a lot better then you have a problem with the rings. If the reading is the same then the problem is the valves and in that case you could use the '70 heads with no problem.

 

do I need to swap out both heads

 

hmmm.... good question, I'm not completely sure, but since heads for both years are pretty much exactly the same I wouldn't think you need to.

 

Actually the 70 heads have a few CC's less than the 72's not much of a diffrence but I would replace as a pair.

 

does the difference in CC's matter or what are the effects of this

 

I don't think you want half the engine at 9.0 to 1 and the other half at 8.5 to 1.

 

You will need to do a leak down test on the cylinder to determine the problem that needs to be addressed.