06 v8 rebuild questions

I have some questions about an engine rebuild on a 4.7l v8.

The factory divides the original pistons and bores into very small divisions of sizes. Likewise with the bearings. Aftermarket parts come in STD, 20 thou, 30 thou oversize. Do I need to bore each cylinder and grind each journal to match the desired clearance with the new Mahle STD pistons and bearings?

I am hoping to just do a light hone and place new STD pistons & rings in without having to grind the crank. Head was damaged only. Trying to rebuild on a tight budget.

Finding heads in Canada has been impossible. Have to buy Toyota new

 

If you're not going to overbore, then you can use STD pistons.

Clamp up your journal and rod bearings using Plastigage, and you'll get an idea about which size you need new:

https://www.plastigaugeusa.com/how.html

 

How many miles are on the engine?

 

200,000km 125,000 mi

 

I think with 125k miles in the engine you’d still be fine with just a hone and new standard pistons/rings, but since you’re going to be in there that deep anyhow AND that you’re planning on buying new pistons to boot, i’d be highly inclined to get the cylinders bored instead of honed. Have you looked to see how much more a shop charges for a bore than a hone?

 

Now this begs the question "why are you rebuilding it?" You said the head was damaged...how exactly? Why not reuse the original pistons? 125,000mi is nearly new for the 2UZ engine, often regarded as the million mile engine. Ultimately the reason you have the engine apart may inform your decisions about pistons and bearings.