so i tried searching the board using words like "port", "polish" and "gasket" and i didn't find what i was looking for which makes me wonder if no one recommends it or no one's attempted it.

one of my previous vehicles was a 94 taurus SHO with a 3.2L yamaha V6. it took well to mods and in the later stages of my ownership i personally ported & polished the intake manifold and then gasket matched the heads and intake ports to the stock gasket dimensions (the yamaha engines were actually quite a bit off from the gasket openings).

has anyone done this to a 07+ g35? is it just unnecessary? i'm not afraid to do it myself obviously but if it's not worth anything then why bother.

obviously i know there used to be pitfalls of not having the correct surface pattern on the insides of the manifold and not getting proper air movement into the heads but does this even apply to an engine like the vq35?

cheers!
Bob

 

The HR engine in your 08 has a plastic manifold. The walls may not be thick enough to port.

 

hot damn, plastic manifold? now i know. thanks. guess ill go for spacers instead. or maybe ill buy a spare and see what i can do. very interesting.

 

I have taken the manifold out and injectors and even bottom manifold before. Its all pretty much well matched. There is only minimal improvements you can do, the biggest in my opinion would we to smoothen out the walls in the bottom manifold runners. With all of this said, I don't believe the end would justify the effort. As for the headers I am sure there would be a place for improvement but changing the headers to better ones would be your best bet I think.

 

If you mean the plenum, then yes it is plastic and actually flows very well. However under the plenum is a cast aluminum intake manifold (runners) where the injectors are mounted. The ports are not polished or anything but they are well matched to the heads and the plenum as well. I don't see any way you can improve over the stock design TBH. I think you'd gain more power by running seafoam and cleaning out all the carbon from the injector "nozzle" and runners than polishing the inner walls. The VQ's seem to collect quite a lot of carbon compared to other engines. I cleaned the inside of my plenum along with the aluminum manifold and there was quite a lot of black carbon deposits that came out. I could see the valves liberally covered with this stuff as well.

 

fair enough. i guess ill go for the cleaning but forego the porting and matching. thanks for the info guys. i'm still learning alot about the vq construction and how our engines are designed, thanks for your patience with the noob questions.

 

Bob,

I also am a previous owner of a second gen SHO and had intake manifold/porting done on that car. Really opened it up! As stated, the actual manifold is plastic. .

I miss my SHO and will probably pick up a 91+ next. Were you on SHOforum?

Enjoy your G35!!

 

i loved my SHO. the transmission was junk but i had done alot to that car. i learned so much by working on that car. and yeah porting that manifold was a giant leap. i always considered going to the contour SVT since it was basically a baby SHO.

i was on the SHOforum, my handle was BlackOnBlackATX.

love my G, i can't wait to start putting bolt-on's on it.