1ZZ TB without intake???

[tmontague]

I have a 1zz TB, and to be honest if you have no other supporting mods then the only advantage is an increased throttle response (this is not an increase in HP). I noticed a very significant difference when I ported my stock intake manifold (which I'm now selling). I now run the MicroImage/Golden Eagle manifold which is also built to match the size of the 1zz TB.

I personally don't think the stock airbox will be restrictive. The engine is a vacuum and i feel the stock airbox is large enough for the amount of air the 1nz needs even with the 1zz TB. That being said this is because even with a 1zz TB, you are still severely limited with the stock intake manifold. The engine is can not use more air because of a 1zz TB, it is still limited by intake and exhaust manifolds.

IMO, the 1zz mod is useless (except for throttle response) without porting your intake manifold or running the microimage manifold. In your case the restriction is not the airbox but the stock intake manifold.