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Discussion Starter #1
I am looking for some ideas as to what may be the problem with my motor. I just put it back together after having a forged lower end built for me (cobra crank, eagle rods, probe pistons). The block is a 98 and my heads are 2001s that I had some minor porting work done on. My old engine burnt up from a bad oil pump and ruined the lower end and the cams. I replaced the cams and the cam journals were still in spec. I not have a rattle from the right head when the motor is close to being unloaded and comming out of the throttle. Under hard acceleration, no noise. Drive it nice and it sounds like it is going to come appart. The rattle does not seem to affect anything in the way it runs. I have changed the lifters (compensators) in both heads and no change. I took the engine out and had it checked at the machine shop and they found nothing. I reinstalled it and the noise is now getting progressivly worst to the point that you do not have to drive the car to hear the rattle any more. I have a local mustang shop and a ford dealer look at it and they both said just replace the head. The motor is back out of the car and going to another machine shop. I know I can not be the only one to have this problem. Any ideas? Thanks
 

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I have a noise coming out of 1 of my heads after the swap it started about 100 miles after it. My theory is the cam caps boltes or out of torque spec after running through the hot/cold cycle a couple of times I have not gotten around to retorqing them yet but hte car runs very strong like yours I have heard of several people with this noise after the headswap and even some mustangs without the swap having some valvtrain noise with no power loss good luck make darn sure you post if they find it as no one else has yet
 

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Discussion Starter #3
I retorqued the cams after the lifter change and there was no change in the noise. I just received word from another machine shop that there is no (visual or noticable) problem with the heads. Any ideas?
 

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I have no idea there are so many parts in the overhead cam it could be one little lash adjuster a little out of whack everyone I have talked to cannot find this problem. I did see where 1 person changed the head and cured the problem but mine are staying put as there is no problem other than the noise. If I find anything on mine I will post it but dont hold your breath
 

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Discussion Starter #5
I think I found the problem. I just took everything apart again and noticed the cyl. walls had alot of wear on them (600 miles). I measured the piston to wall clearance and it is .007" to .0075". Stock is .0015" to .0026". Looks like I will be buying larger pistons and boring the block. Everything in the heads is up to specs.
 

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Yuck hope thats not my problem justed turned 2000 on my new block my oil pressure just started t go up so I think the rings are seated now moved from the r in NORMAL to the A now once the 4:10 are in this weekend I will stomp it and hope for the best. Keep us posted you are the only one that is making any headway on this issue
 
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