So here's my situation guys...

I currently have a 5vz-fe with 160xxx miles on it. So far, it has blown 2 head gaskets (both under previous owners, one in 2002 and the other in 2010) the heads were warped and resurfaced. As of now, it runs strong. Kinda. It has a piston slap due to being driven while hot. After I purchased it, it overheated and the seller had it towed to his mechanic's shop. These people were idiots. Didn't fix a thing, and ruined the piston skirts in the process. Took it to my mechanic. Had it running well with a few cooling system flushes. But now I'm stuck with the piston slap. I have noticed lately white smoke on cold starts. It's not a lot. Only noticeable in little puffs that come out when the motor is revved. The exhaust has a weird, almost coolant like smell to it. So I'm thinking, damn, blown HG. But as far as I can tell, no fluids seem to be mixing. And there's no other symptoms. Just the exhaust. But the piston slap alone is enough for me to want to rebuild down the road.

My question is, should I rebuild? Or replace? And when? I am on a tight budget, being a student in high school making minimum wage. Money is light most of the time. I have a 97 Geo Prizm as a reliable back up. So, should I drive it till the motor blows? Then drop a new one in? Or try to salvage this one while I can. Either way, I won't be doing this work anytime soon. I only have about $400 saved for any engine work. And it's running strong now. So I'm not worried about doing anything immediately. What do you guys think?

You already know that engine has been abused for years. I'd say start fresh.

Normally I would vote for a rebuild, but not in this case. That motor has been too abused for too long.

I say find a used engine. All day long you can find them for 800-1200 from a crashed truck. You might even be able to find one that is still in the truck and runs before pulling it. With that slap in the piston it is only a matter of time. Think of this way, you will still have extra parts off the other block when you are done. Not a bad thing.

Blue

What would u suggest on my2000 sr5 4 runner should i rebuild it or jusy buy another5vz and pop it right in whats better and cheaper?

If I were you, I'll buy a used Toyota engine (of course low miles!) over a rebuilt engine. If it is from Japan, I'll buy it right away. If it is domestic, miles + check inside valve cover gives a good idea about the engine

Rebuilt engines will run about 100-150 K miles and will start burning oil after that.
If you check the compression on a rebuilt and a good used engine, the used engine will show better compression. I rebuilt a 3L hilux engine with genuine toyota parts, yet, it takes extra turn or two to start over a used (JDM) engine.

Go for a use JDM engine. Do a compression test before making your purchase.

I would suggest you stop giving flat-out false advice such as this. An engine that is rebuilt properly, can last just as long or longer than a factory built engine.

Properly rebuilt is the key.

There are people out there "rebuilding" engines, that are barely qualified to change oil. Obviously an engine that is "rebuilt" by one of those clowns, will not last like a properly rebuilt engine.