why would the car need oversized valves for an NA setup? At the power levels even the most extreme NA car can dish out, the stock valves are fine.

GY-Z - rather than going off of internet knowledge, you need to sit down with a reputable engine builder and go over your goals, budget, etc etc.

 

I never said he did. That is what comes with the Nismo package.

 

I see what you mean

Do we know for sure that the "NISMO USA" heads are in fact just VQ30 ones?

 

Do the oversized valves fit the NISMO head perfectly or do you need heavy porting before they would fit?

The Alu valves would wear downe quicker than the Ti ones due to steep angled camshafts, so strength would be a benefit for running the Ti ones. Alu is probabally about as lite as Ti so I dont think weight would be as much of an issue in our case.

 

then shouldn't swapping my piston to a 11.5:1 forged piston had the same amount of gain? altough itz a lot more $$.

 

thatz sounds a good advice, but i'll have to know what i want at the first place, isn't it?

 

I would just change the heads, why spend more money than you need too. It is up to you. But switching head is alot easier than swapping pistons. Can you do the work yourself on the piston swap? I am sure you can do the headswap.

 

Does anyone have more info on the VQ30 head?

 

Yes does anyone have anymore information on this? Also how hard is swapping the head? Swapping the head along would raise my compression and thus raise hp correct? I'm just trying to make sense of all this.

 

Jason, Are you guys going to finish the install of the nismo 46cc heads on your vehicle(s)? I sure hope so. I'd like to know how it turns out and if it will work without any other engine (physical) modification. And I'm wondering if the compression is too high to run on 91 octane (crappy CA grade) and will cause early detonation? Concerned partly do to the quotes below.