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Discussion Starter #1
I took my 66 Fastback for a cruise today and killed it. I was laying some rubber, had the car sideways, and something went wrong! Number 4 cyl has no compression. I blew air into the cyl and it came out the exaust. At least it didn't come out of the block. It looks like the valve spring is down a little more than the rest. I'm hoping I just floated a valve and bent it.
 

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Discussion Starter #3
Well, I got the head off, Bent number 4 exaust valve. I can see where it smacked the piston, no damage, just scuffed it. On the bright side, the inside looks fresh, I can still see the cross hatches. The inside of the block is painted for quicker oil return, the pistons are forged flat tops, by the sounds of the engine, it has a scary cam. I don't know a lot about casting numbers for Ford heads, but these look like closed chamber. The egine ripped-ass before I bent a valve. the compression must be 11 or 12 to 1. Now the question is,Why did it smack a valve? I was revving the piss out of it when it happened. It could be just a weak spring and the valve floated. I am worried about the lift on the cam though. It might be cheaper just to get a set of aftermarket heads than to have these re-built, or I could just slap a valve and a set of springs and call it good. The problem is, this is a 66 GT with what looks like the original block and heads.
 

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How high exactly were you revving it? Because if you spin up the motor to high you will encounter valve float and there really isn't much you can do without purchasing new parts. Id recommend looking into the comp cams behive valve springs. Heard a lot of good things about them.
 
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