2 ways to increase displacement are to either increases the bore or the stroke. No way you can bore an engine to gain that much displacement. I've never heard of anybody building a stroked 3.4 but it would be possible. I still don't think you'd be able to get to 4.0 litres. Realistically though if you were just to increase displacement without upgrading anything else, you may be able to gain about 30 horsepower or so, but you'd also be making a decent upgrade in torque. Now the reality check is that this would probably be very expensive since you're probably talking about completely custom crank, rods, pistons, etc... the obvious alternative to me would be to forget the displacement and add a supercharger. Probably make more power anyway, be more reliable, and a great deal cheaper.
I called LC this morning and they said that the race motor is going to run 15k, street/strip motor is going to be around 12 and their rebuilt is going to be 5-.6k. Thats some $$$ but im sure some people are willing to pay it.
Other than LC is there any one else out there that is working on parts for the 5vz?
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