Engine swap question

So according to the dealer, Gen 4 uses silicone gasket maker for VC gasket. No actual gasket. But the cylinder head is the same part number from 10 to current. There have been three revisions to the head gasket. Dealer says that the mechanics of the engines is the same. Subtle differences in PCM calibrations give the 16 and newer engines 40% volumetric efficiency. Versus 37.5% on the 10-15 engines.
LKQ will give me 100% refund if the engine is not correct. Their interchange says that it will work. They do say to use all the sensors and external parts from my old engine to keep the electronics happy. Seems that there is an almost endless supply of low mileage engines in the LKQ inventory.

 

So another week down in the search for the right engine. I have noticed something very peculiar. I have been in touch with LKQ on a couple of occasions. The following has caught my attention. Gen 3 engines, even lunar mileage ones are getting premium prices. But, especially in Cali, which I would gladly pay shipping to Indiana on, a Gen 4 engine can be had for as little as 800 dollars. Compared to prices on the Gen 3 in Indiana are 1250-1700. Does anyone have any insights on this? It makes no sense to me, but maybe someone else can understand it.

 

I’m still not entirely convinced that a Gen 4 couldn’t be used in a 3. Problem is that no yard in a 200 mile radius of me has a Gen 4 out on a pallet or shelf to lay hands on. I had a Gen 3 that did not pass a leak down test. I have a portable compressor and the hose to my compression tester that I used. Found a blown head gasket on the engine I was ready to buy with cash in hand.

 

A shop near me has a Gen 3 engine that tossed a rod out and on a pallet. I took some pictures of the mounts and such. The pictures of the Gen 4 engines on eBay and other sites put mount flanges and sensors in similar locations.

The yard that had the Gen 3 engine I was looking at disassembled the engine that I was going to buy. It got tossed in the scrap bin. They wouldn’t even let me buy the short block. I’d have thrown a head gasket on it, but the yard owner said that he’d rather not try and find me another engine in 90 days.

 

I do know the intakes are different, but sealed with the same o-ring style gaskets. The exhaust manifold is different due to change in EGR tubing exit from converter versus manifold. The valve cover has a vent(?) below and forward of the oil cap the Gen 3 doesn’t have. However that is under the engine cover that sits farther forward of the Gen 3 cover.

 

If I was 95% sure it would fit, it would be on my engine stand getting parts changed over. As it stands I’m at 65%. I’d like to put my own eye on it to see. I am thinking of visiting a Gen 4 and doing my own underhood inspection. Not sure how my local dealer will respond, but I’ll take that chance.

 

Holy hell! I’m going to have to drive over just to look at some of their custom work. A Pruck as they call it, a couple of Gen 2 limos. A boat-Prius. Wow. Now I have seen it all.

 

They have several damaged Vee Prii on their site too. Some of them maybe terminal, but not engine end damage. Fallen trees and rear end damage. Might be worth a look.