Question about piston replacement

[Seawulf]

Well, with the nitrous and boost going up soon; I've started thinking about upgrading the internals but I wonder what exactly is involved in doing it.

On the Focus forums they say that to replace the rods and pistons you have to take the engine out, get it rebored, get the whole "rotating assembly" rebalanced. Huh?:confused:

Now, my dad who's been wrenching for 30 years or so says you don't need to do all that stuff, just drop the oil pan, take the head off, slide the pistons and rings in, hook it up at the bottom to the crank, bolt everything back up and start'er up.

What's the deal?

[overfiend]

pulling the engine? maybe...boring? dont think so. i think it'd just be the time to do it if you were going to. but to my knowledge it's pretty much just a direct swap. you may want to rebalance as well...i want to say that is what's recomended for the v6, and i think its pretty universal. i dont think i helped any hehe

[Jagular]

you can change the rods and pistons with the engine in the car, BUT, you have to make the rods and pistons that you get weight within 2 grams of what the factory stuff weighs. That is near impossible as the aftermarket stuff is almost always lighter than the factory stuff. Another thing to consider is changing the main bearings. I would definatly pull the engine or get a donor engine and rebuild it. Those engines are a dime a dozen around here. I was at the yard the other day and counted 6 with the VCT and 15 wihtout. If you get one that has been blown up or is missing parts and is in the core pile you can get one really cheap. I can build you an engine if youd like as well. I sell all kinds of those parts and have built one of those enignes before. They really run well once you redo them and port the head and stick some cams in them, especially with a turbo and nitrous...

[NKTasty]

i agree....

if you're going to start doing internal work, just scrounge up a few bucks to get a spare motor and take your time building that so you can do it all right. nobody wants to do major engine work, and have something go wrong in a week and then your car is down. zetec motors are cheap, you can easily get one for a couple hundred bucks in perfect working order from a junkyard

[Ness1216]

So how much would it cost to rebuild an engine if you were doing most bang for buck? Also when rebuilding an engine what needs to be replaced and what stock stuff can stay? I was thinking valve rings, retainers, springs, camshafts, pistons, connecting rods. Do you have to get the crankshaft replaced and is it expensive to replace? what parts am I missing out on for a good rebuild to make the motor stronger internally for boost or nitrous etc.? Sorry if Im asking dumb questions but I will feel a lot better knowing this.