Difference in cylinder heads... best one?

97 Passat tdi.. ahu, right? Is the 1z head better? If so, why? Does the euro version have the same head? If not, which is it? Basically, which is the best oem head that will bolt to the 1.9 in my 97? If valve sizes and angles are different that's ok. I'll just get the correct pistons and hone the block if necessary.

My goal is to get the best casting to start with and CNC it. I'd prefer something that would bolt right on my 97 Passat, so the engine didn't have to come out.

Which head came on the 130 hp Passats in Europe? Does it have bigger valves?

Thanks,

Chris

I would contact Franko6...see the 'cylinder head repair' link in my signature for contact info.

Frank is a 'god' when dealing with these heads, in repair, and knowledge.

Tony

130hp Passats in Europe are a whole different animal. They are PDs. You have an injection pump. Completely different animals (and PDs like to eat cams/lifters).

Your '97 Passat should have a 1Z. The AHU is the later revision of the 1Z engine that mostly came in Mk3 Jettas here in the U.S.

As far as differences in the cylinder head go, the 1Z has larger valve stems. That's about it. The larger stems may actually limit flow just a touch more than the AHUs.

If I recall from a past discussion with Frank, you can't get the larger stem 1Z valves anymore, however you can retrofit the smaller-stemmed AHU valves no problem. Otherwise, the heads are identical. So the best head for your car is the used OEM head you find in the best condition.