VG30 stroke, bore, displacement questions

[scottgas]

How much displacement can a healthy VG30 block support if not running boost and wont be on a race track?

The reason I ask is my son's car is a bone stock '96 Base Coupe. I believe it is a California model. Engine has 93,000 or so miles and runs perfect. For just in case something ever happens to the engine, it's good to have options. My son doesn't believe in LS swaps for his "90s Japanese super car"...lol. He really loves his car. He also, at this time, doesn't want turbos, doesn't want a VQ swap, or a turbo swap. I said we could always rebuilt the engine for boost and convert it to a turbo engine. He said no and said that he wants ITBs. If we have to go full N/A with ITBs, we might as well also go bigger cubes.

How much stroke can a VG30 block support?
How much bore can a VG30 block support? NO BOOST

[VStar650CL]

The folks I know generally agree that a 2mm overbore (87mm -> 89mm) is safe, which would give you a VG31. Some say 90mm, but the VG30 has relatively thin walls compared to the VG33 so you might be asking for trouble. They break through at 96mm.

I never heard of anyone making a stroker crank for the VG30, although maybe one of the Z mavens in here will correct me.

[scottgas]

If I went down this path I'd probably replace the crank. Not a fan of bolt on counter weights. I remember back in the '90s people with high powered Z32s found out about bolt on counter weights the hard way. I just wonder how much stroke a stock block can support

[itsa300zx]

I don't under stand why your son wants to waste so much money???LOL.
What are his goals for the car???

Crank shafts (stroked) for VG30 can't be bought off the shelf. Custom JUN cranks are the only ones I've heard of, those start at $15K +.
IIRC they were 3.2 or 3.3L displacements. And remember the larger the bore, the less RELIABLE power.

[scottgas]

It was a conversation over whiskey...lol. he like high revving na power. Honestly, you could probably have a custom crank made for far less than $15k. When he got the car in Jan, 2018 he took a dive into Z32 history and it's competition success. The heart wants what the heart wants. If we ever go down this path, it WONT be his daily. By then it will be a 2nd car for him. I remember back in the '90s, in either Sport Compact Car or Turbo and High Performance magazine, there was a story about 2 close friends that had Z32s. 1 had a turbo and the other an NA. They both built their cars. The na guy ended up making just over 300hp and the turbo guy was making 500-600. My son's car is pretty light being a base na slickroof with cloth seats. 300hp would be pretty fun in his car

[VStar650CL]

You could always swap for a VG33. They fit, albeit with some expensive tweaks like a modified harmonic balancer. The payoff is that there's a lot more metal for making mods (and a lot more mod parts, or a least there were back in the day).

[scottgas]

and youre stuck with 2 valve heads. One of the things my son wants to keep is the look of the factory engine. He loves how the engine looks