Engine intake manifold

intake manifold

Anyone compared the intake manifold on the 2000ish vvt-i and ours? Although i havnet had mine off, the plastic seems like it could be more restrictive than the older metal tubular one. Just an idea of someone running out of mods fast... ha

Clay Sanderson

actually our intake is probably better. The plastic won't conduct heat, therefore our intake temp is cooler.

the plastic ones can be made smoother for better flow compared to metal..they can also be formed better

Is our intake manifold really plastic? Or is the plastic just a cover. And yes, the plastic COULD be formed better then the metal, but its only a factory intake manifold. so IS it formed better then the metal one?

Yeah, it is plastic and they can mold it better and smoother than the aluminum ones.
I've taken mine off and removed many restrictions with my rotary tool. I smoothed down 2 vaccum line fittings protruding about an inch in near the inlet and a few ridges near the inlet and in both outer outlets. I enlarged the outlets to match the intake ports (over 1/8" wider and 1/16" taller). I also cleaned out imperfections and polished the intake ports down to the injector lump, about 1-1/2" in. I then bored out and polished the TB and rerouted its coolant lines. All this gave me an impressive gain in torque and max power....more than with the CAI alone.
By the way, I've recently also smoothed out and polished the exhaust ports about 1-1/2" in. They are rougher than the intake ports and have a big ridge on the upper and side edges. I've improved the puny exhaust manifold and its collector as much as I could but it's clear to see that it would benefit greatly from a header. Slapping on a $33 2" Cherry Bomb muffler and a 2-1/2" S.S. tip really did the trick for now too...

I don't know if I care for the plastic manifold, a lot of buicks had problems with theirs,we'll see, but if you're looking for power than porting is a good way to go. I've read many times that the bottleneck for many engines is the heads, port matching the heads to the intake is a great way to make power on any engine. I haven't looked inside the 1ZZ yet so I'm not sure how well it would respond to a good port job

i have mine sitting in my garage you can buy it and you can mess with it. i have all the parts from the supercharger install sitting in my garage. spark plugs etc the plugs only have about 7K on them and the manifold could be smoothed out to get even better response. email me if interested