please help.......I have a 2005 gt with a 4.6 3-valve, is there anyway to repair a cracked cylinder wall. Any suggestions would be helpful.

 

I'm not very familiar with the 4.6 engine block, but I would think the block would need to be replaced.

 

Yep, need to replace the block if it's cracked.

 

that doesn't happen to often but yea I would say it needs to be replaced.

 

all this from a plug change...I think you might be ahead to just pick up a used motor- theres enough wrecks by now, they are not that hard to come by. broke plug, ceramic in motor, broke valve, unsure if gaskets were ok or timing, now maybe busted block...sorry, but even as 'save everything' as I usually am, I'd say stick a fork in that one, its done
replacing a block is way way more than just a swap, should have a whole new shortblock(pm rod mighta been damaged when it hit the valve, crank could be twisted/stressed...), and at least the one head is probably 'iffy' at best... a longblock wont be cheap, still a fair bit of parts to swap, a complete pull could be a afternoon job to swap/drop in.

or if you dont want to mess with it, see what kinda offers you can get, I always wanted to drop a 429 in one, bet theres a lot of others out there thinking similarly... If I saw a GT local with a popped motor, I know I'd be eyeing it

whatever you decide, good luck on it- but I really think if you can find a running/wrecked one you could get a good pull that you could hear run first, for the least cost... I think Corostang in here sold his motor for like 1500 IIRC and it was a super low mile one...