Hybrid Vg...sort Of

[180sx]

So I've been doing some research to help my pathy with power. Obviously there's VG34 and ET, but in the mean time, I've been thinking about VG30 heads. From what I've found, the valves are the same size, but the combustion chamber itself is smaller. Couple this with the 3.3 bottom end, and the compression ratio would raise a little (maybe by like .3 or something) but I have yet to confirm this. The heads are supposed to have a better flow design also, but again, I have yet to confirm this. One thing though, if the heads are the same, then the cams could just be used. They have higher lift and duration then the 3.3 cams. Anyone have insight to any of this?

 

Jose

[MY1PATH]

you're a little backwards, the 3.3 heads have a more efficent flow design due to a more advanced casting process that was intoduced in the early 90's. These newer castings also allowed more thruough combustion. despite the slight differances in chamber the compression remains 9:1 reguardless of combineation.

Yes running a 3.0 cam on the 3.3 is a good idea.

all internals on the 3.3 and 3.0 SOHC heads are interchangeable.

 

 

[BowTied]

Make sure to know if there is any valve interference when changing heads. Make sure you are referencing stock height head gaskets or know the difference. I have no idea if this is really necessary or not, but if information is lacking play it safe. g/l

[MY1PATH]

that reminds me, valve clearances are the same but if you mix vg33 and vg30 block and heads you will need to get a small rotary file like on a dremel and walk the holes over in the gasket for the water jacket as they are just slightly differant.

[Tungsten]

use vg30e cams on a vg33e

if you get a check engine light good luck