think about it... that doesn't make sense, why would older technology(d16z6) be better than the newer motor(d16y8 )??

 

Because they weren't redesigning for performance, they were making technology advances in FUEL ECONOMY and EMISSIONS.

 

both heads are ALMOST the same because the compression height of the piston in inches are the same(1.154 in.), the cylinder head volumes are the same,(32.8cc's), and the valve sizes are the same too(30/26). i think the only differences are the Y8's intake manifold and cam profile. lift, grind, duration ect. SO the heads are TECHNICALLY the same, I say get the Y8 for that 2 extra horses!!!

 

WRONG, they aren't even close to the same. The compression height of the pistons is different the Y8 is 29.5mm and the Z6 is 30mm. The piston dome displacement is different as well. The cylinder head volumes are different, teh Y8 is 32.8cc, the Z6 is 34.6cc. The valves are the only thing that are the same. Please check your facts before you post. http://www.knology.net/~jediklc/D.htm

Also, check these pics out taken from http://pub143.ezboard.com/fhondadser...cID=672.topic.

 

ok so the z6 head flows better, but wouldnt you want higher compression from the y8? because yes, the z6 head does have greater combustion chamber volume, but smaller quench pads wich gives greater risk of detonation. The y8 head on the other hand, gets a boost in compression because it has less combustion chamber volume, and squared combustion chambers. a plus to the y8 head is the larger quench pads to help reduce detonation from the high compression when the head and block is mated. so it boils down to either better top end(z6) or somewhat less of a risk of detonation associated with higher compression with the y8. But thats just my opinion. Sorry for posting the wrong info about the head comparison, I was looking at the wrong engine when i was getting my sources!:o

 

Now you got it!

It's all depends on what you want to do. Sometime the lower compression is what you want, i.e. turbo setup. I am not saying a Y8 head is worthless, I am using one for my setup.