I know it can be done, thats not my concern. I am going to smog this engine in California, which means I must run the stock D16Y8 OBD2 ECU. As I am sure most of us know, the stock ECU has different base timing for the Y8 vs the Z6. I know the changes are in the cam gear. With this in mind, would I simply swap to a Y8 cam and cam gear and be good? I'm trying to determine if I should toss the current Z6 head I have and just source a Y8 one to avoid problems down the road.

 

use a z6 cam in z6 head i tryed and z6 cam in a y8 head and didnt pull for **** so i put a y8 cam in it and it pulled fine and spooled up the turbo great

 

I don't think you understand what I am asking here... The base timing maps on the STOCK Y8 ECU are set for 12 degrees. The base timing maps on a Z6 ECU are set for 16 degrees. I need to smog this engine. If I leave the Z6 cam in there but run the Y8 timing maps, I think its going to cause problems with the results out the tailpipe. Remember, California smog here. Its a lot more technical then the other states. I think I am going to need to run the Y8 cam and the Y8 cam gear... then the only other concern is the smaller combustion chambers (quench pads) in the Y8 head vs the Z6 head. Obviously this will effect emissions to a point also... is it enough to fail me though?

 

I don't have experience with the cam swap but I've heard it's interchangable. The distributor will also have to be changed since the Y8 and obd2 ecu uses a crank angle sensor while the z6 does not. *edit, shifty35 is right, dizzy not interchangable.

 

^^ Distributors *not* interchangeable. The Z6 / D15B vtec has a unique bolt pattern. The Y5/7/8 has the same pattern as the old D15B2/7 D16A6 dizzies. You'll have to fit the Y7/8 electronics into the Z6 housing.

You can run the Z6 head, I'd even be comfortable using the Z6 cam. Make sure you use the cam gear that is the same as the cam to avoid timing errors. Z6 gear with Z6 cam, Y8 gear with Y8 cam. They are 4.5 degrees different.

Put it all together and sync the dizzy so you get 12* on the Y8 ECU - it should run fine and throw no codes, provided all the other OBD2 bits are in place - crank sensor, knock sensor, fuel tank sensor.

 

I know it will run fine. The timing events will however be incorrect as the cam timing will be off. That combined with the larger combustion chamber might be enough to throw off smog.

 

The timing events will be darn near identical if you use the correct cam gear and sync the distributor properly. Z6/Y8 cam have lift / duration that are almost the same, as well as identical centerline / lobe separation.

I don't imagine that it would be a problem.

 

u can us a obd2 dizzy on obd1 car all u do it repin the plugs the white piece coms out and us a pic to push down on the pins they should slide out i had to do the same thing with mine when i put a y8 head on a z6 block in obd1 car

 

z6 and y8 cams are the same just the gears are diff u run a adjustable cam gear and have the cam degreed to correct the diffrance if u change cams

 

love the cc design of the y8 head, hate the swirl ports : (

anyway, don't worry about it. just stick with whatever cam and its corresponding sprocket, make sure you have the proper base ignition timing as per the distributor, and run the p2p without fear. it'll be fine.

 

Now when ordering ARP head studs I match the studs to the head in use, not the block, correct?

 

hmm...man it's been a while!

i think with that setup you need one stud for a z6 and the rest for the y8.

if i recall the lone z6 stud goes in the passenger side rear corner.