Mr. Dabolina

I've seen and read about a lot of random rigged together bullshit on Hondas but I've got a weird one for you all:

I helped my friend pull an engine at a local junkyard. Car was a 96 EX Civic with what appeared to be a D16Y8. The stamp was all gummed up from a leaking dizz o-ring so I just did a quick look over of the engine. Everything looked familiar to me from my days with a D16Y8 and the car looked pretty much unmodified except for a fart cannon and a smashed up rear end.

I checked the ECU like I always do. Factory D16Y8 5-speed ECU:



We yanked the engine. Got it home and started cleaning it up. Uncovered the block stamp and:



We were kind of shocked for a minute and then the "Oh ****" set in. The engine had a CKP sensor and a knock sensor so it was OBD2, which also means 3-stage VTEC-E, and a dual VTEC solenoid. But the solenoid was a single.

We took it off and found this:



The 3-stage solenoid had been switched with a 2-stage one off of what I assume was the original Y8. You can see the outline of the gasket for the old solenoid against the oil film from the new solenoid.

I'm a little unclear about how exactly 3-stage works but from what I'm reading it looks like when running on the D16Y8 ECU, the engine will either be in 12valve or 16valve low cam until the solenoid is activated then it would go into 16valve high cam mode.

Does anyone know what the default for the D15B valvetrain is? Is it normally in 16valve low cam? It looks like a Y8 head and this head have the same number of oil galleys and they're in the same place. It makes me wonder how all of this works if the heads have the same casting and oil passages.

From the picture below. It looks like there is only one synchronizing pin, just like a normal Y8 but I dont remember seeing a timing piston or timing plate on an Y8 rocker assembly.



I'd really appreciate a BRTUALLY technical explanation of how VTEC-E works in these motors.

I'm just absolutely mind-fcked by this. Logic tells me that just slapping a two-stage solenoid onto a three stage head shouldn't work but apparently is does to some extent because the car was driving around.

I like to ramble a lot so I digress, I'm going to keep reading into this, but I just wanted to see if anyone has seen or tried this before and with what level of success.

Thanks a lot HT.

kfish

This is actually my engine, but Mr. Dabolina is helping me out. Just to confirm it is indeed the 3 stage VTEC, I removed the valve cover and rotated the engine CCW, and indeed only one intake valve opens per cylinder.

This engine will be going into a 1994 Civic EX, my question is can I actually make this engine work properly in the car without a bunch of rewiring and a tuning nightmare?

If not, I have a known good Z6 head laying around collecting dust. I've done a bit of reading on the OBD1 VTEC D15B's and I know that the head casting is the same between the D15B and the D16Z6. So in theory wouldn't swapping the 3 stage head out for a Z6 head basically yield an OBD1 VTEC D15B?

Any help is appreciated here. This whole deal has been a slew of mixed emotions for me haha.

HondaPartsHero

Swap heads and save yourself the headache.

kfish

That's pretty much my thoughts. I got the 3 stage head taken off tonight, and for fun I just sat my z6 head on the block. Everything sat down and lined up perfect. I assume as far as timing components go I'll use D15Z1 stuff like a normal D15B?