JZX NZ

I'm curious because I have never heard of this but worth a shot to see if anyone has ever seen it done,
ported polished flowed? has anyone ever heard of a vvti 1jz head having this done and results?

I read somewhere that on the Yamaha head, you can only make them worse if you muck with them?

I know someone who built a 1.5JZVVTI and it was mint until he got the headwork done, after that it ran like a pack of ... You get the picture.

I may be wrong, however.

Relatively rare on the 1J VVTi heads, a lot of guys at that stage are using non VVTi 1J heads and modifying them- the initial port shaping & valve shrouding etc is very useable.
JZ heads are a great design in factory form, hence the awesome power most people get with an unopened package. Ive found the later model heads are so well finished from factory, they only require a light clean up & possibly a CC check to make sure all chambers are within tolerance- hardly worth it!
Factory porting will get you past 600hp easily & yeah unless someone knows what they are doing, it can completely change your engine characteristics for the worse.
The crew in Aussie with the JZ Celica (6 sec?) thingy do a bolt on 1000hp race prepped head! Awesome!