Ok so I performed a leak down test on my 1991 302 and what I came up with is that the #3 cylinder is leaking air into the intake manifold. I know I am going to have to take the head off and replace the valve more than likely. But do any of you have any other ideas what might be the problem before I tear into the engine? The valve springs are new so I don't see that being a problem. If it does turn out to be the valve would you replace all the the valves on that head or just the one? Any advise would be appreciated thanks is advance.

 

did you over rev it? I would just replace the one

 

Are you sure you were on the cam's base circle and that lifter was not pumped up?

 

Thanks for the replys! Unfortunately, I was not driving my stang when it happened so I am not exactly sure what took place but since it was my dad driving I would assume that he was hot rodding around and yes over revved it. When I did the leak test I checked every cylinder just to make sure I was doing it correctly and they were all good except for the #3. Once I determined the #3 was giving me problems I checked it multiple times just to make sure I was at TDC. Do you think that I should also take the head in to get resurfaced and make sure there are not any cracks? Sorry for all the questions but just looking for some good advice. Thanks again!

 

Have your dad buy you a set of good aluminum heads.

 

If the head was all right before then it should be ok now. other then the valve and the guide should be looked at real good. look at the pistons if the valves hit you will see the marks on the tops and if they all hit you will want to look at all of the intakes.