custo at the shop is getting the aebs stroker kit for his 350z. thinking about picking up the crank, rods and pistons. would this be a drop-in into a vq30de 4thgen block? only con i have heard yet is that the rods from the vq35de are somewhat weak?

 

please note that the vq35de has a longer bore and stroke than the vq30de, hence the larger displacement

i do not know the technicalities on the rods, but the pistons will be larger than your vq30 ones, no drop in.

 

It's also been proven that an increase stroke on the VQ30 (i.e. the VQ33 stroker setup) will cause the pistons to hit the head. So either way, it's not happening.

 

VQ35 rods are stronger I hear. It is the rod bolts that are weaker and failing at high rpm as I understand it.

 

That's how I understand it, too. SR20DEN was supposed to be testing stronger ones from ARP, right?

 

The difference in deck height is only .6 mm, less than the thickness of the head gasket. All it would take to work is a custom gasket, or have the wrist pin holes offset drilled, or maybe mill the tops of the pistons.

 

Could we run a double gasket?

 

I think this is the second time all of this has come up. The problem with running a thicker gasket, is that it would alter the valve timing. Advancing the timing on one bank, and retarding it on the other. I am pretty sure I am recalling this correctly. Milling the pistons could be a possibility, though it seems that if you were doing such a setup, that you might be able to spring for a set of custom forged pistons built to your specs.

 

You do remember correctly, and admittedly it is not the most elegant solution, but let's see how much of a difference it is going to make.

A cylinder head is moved out by .024" (.6 mm). The radius of the primary timing gear is about 3 inches. .024/3 = .008 radians, or less than half a degree. So the timing of one bank would be less than 1 degree different than the other bank. I doubt that would be noticeable.

 

But the engine would still run smoothly?

 

Probably so, but by doubling up the head gaskets, you would be sacrificing your compression ratio, though this might be negligible as well de to the added deck height. Custom pistons would be the best all around. Then you would have the benefits of added displacement, higher compression ratio, added reliability as opposed to a dual gasket/thicker gasket configuration, and you would not alter the valve timing at all.

 

Which head would the VQ33 have? The VQ30 or VQ35 heads?

 

The VQ35 heads would result in 10.3:1 (slightly less if a thicker head gasket is used), higher for the VQ30 heads (over 11:1, iirc).

Using the VQ35 heads on the VQ30 block results in an altered squish area, which may be detrimental.

 

I would assume VQ30. Ported I would also hope.

 

It advances bank 2 by X and advances bank 1 by X+Y. If Steve is correct the difference could be removed by adjusting the chain guide between the banks.

 

So if the 3.3l is .6mm over from the deck height, then doing the 3.2 is .6mm under? I don't have a copy of the 2002+ FSM, anyone want to tell me what the CR would be in a 3.2l? I've read a couple of the VQ33/VQ32 threads, and never saw anything definte, although http://forums.maxima.org/showthread....light=destroke
did have some intresting information overall. Any help is appreciated as always senors.

 

If you lay out the cams and gears on a bit of paper, they would both advance, as it is 60 degrees between banks you will find that Y from SR20DEN's post is about half of x, so approx 0.5 degree error.

Mike