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Hello all. This is my first endeavor into swaping heads. Most I've done so far is rocker adjustments on the stock heads. lol. The engine is a stock '67 289 w/ 2 barrel carb. My exhaust seats have been making lots of noise so I recently picked up a set of 1990 302 heads to replace them with. According to what I've been reading, they should work fine. They're complete with valves, springs, rockers (including the little spacer brackets the mount under the rockers too), everything except the head bolts and push rods. Before I dive into this, I wanted to see if the 289 push rods will work or if I need to go pick up some 302 push rods. Guidance here would be very apprecieated. Thanks.
 

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So, you are getting ready to install 'pedastal mount" heads, on your 67?
How did you determine that your exhaust seats are making noise? That doesn't make sense to me. I mean, if you feel like you need to change the heads, then the ones you have should work, but I'm just not clear on the diagnostics that got you there...
In all honesty, you should measure for correct pushrod length anytime you go from a known to an unknown. I know that Ford used 3 different lengths of "stock" pushrods between the late 60's till he early 80's....
 

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An exahust leak will very much sound like bad lifters etc......just for giggles try a fresh set of gaskets and see if that takes away your noise....your gonna need new ones anyway....what the heck
 

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exhaust valve leak problems will usually result in a popping sound in the exhaust system. One can hear it plainly at the exhaust tip. Mild cases can go away as the rpm is raised. Exhaust leaks will be more of a ticking noise that does not go away with RPM increase. You will hear it more at the leak source such as where the manifold / header meets the head and not in the exhaust tip. Hope that helps a bit.
 

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Discussion Starter #7
To answer Woodsnake. I learned about why those heads require leaded fuel. The exhaust valve seats (among a few other things) need it because they're made of a softer metal. Over time they wear and will begin to make noise. When the engine is running, I can hear a soft ticking sound coming from the head. When driving it would get louder when the rpm's went up, but engine load or throttle didn't affect the sound. Thought It was an exhaust leak at first too. Tried tightening all the bolts. Didn't change a thing. So while it was cool I sprayed a little soapy water on all the connections looking for an air leak. Nothing. Tried readjusting the rockers. Didn't change the sound. So instead of removing the heads and having them completely redone (expensive and i'm poor. lol), I just found a really good deal on the '90 302 heads I mentioned before. Thinking that installing newer heads would just be basically a good idea.
 

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You might lose some power if the combustion chambers are larger then the 67 heads. I do not know the size of the 90 head but worth looking at.
 

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That all certainly seems reasonable, I just never thought I would be able to hear a valve closing..The 90's heads would in fact already have the hardened seats. Again, to be on the safe side, you should confirm the length of push rods.
 
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