I've seen a few V8 FDs at the track and they seem to be really neat cars. However, when it came time for me to purchase one I went with a single turbo rotary. Though the weight difference may be minimal, a quick peek in the engine bay will reveal how much engine mass is further forward in the swapped car. A stock 13B will have a CG clearly behind the front axle. I'm not a suspension or engineering specialist but I can see how that could adversely change the cars driving dynamics and I'd rather try to preserve that balance.

If I was not tracking my car, I definitely would consider a V8 FD. A turbo S2000 would be similar to FD and overall speed would be determined by money alone, same as any other car. I prefer the complete package of the FD over the S2000. Fun Fact: Did you know that when the suspension of the FD is compressed 2 inches it gains -3 camber to aid in handling?

One thing I can attest to though is that FD stands for "financial disaster". It cost a lot of money to mod and to keep it running properly. If you are not making big bucks I would advise you to stay away from this car. But if your pockets are deep enough, you too can be rolling around on 400whp with a smile on your face. I think of the V8 as cheating in a good way because you get the gas mileage and reliability. You just won't be rolling around in the "intended" package, which is what attracted me in the first place.

 

If you really want a FD my advice would be to pick up one with a blown engine for under $10k then spend another $10k on a rebuild/turbo upgrade/tune. Then you'll have a nice, trouble-free ride for atleast 80k miles depending on how high you boost on pump gas, 450whp should be max at 91 octane without water/meth injection. Each consecutive rebuild should be $5k or less which you should have sitting around in case your oil metering pump dies (w/ no premix) or your engine builder does a sub-par job.

Don't skimp out on the rebuild or a $10 part can make you start over from scratch.

 

Another option, but only if you want to keep it for more than a year or two:

If you don't trust your car with boost, you could get a new or barely used MY06-MY08 for $25-30k, drop $8k from the sale of your car on the boxed rotrex high-boost kit and clutch, and then put the other $8k down on the new/newer car. You'll have a brand new car with 375whp, and even if you get a brand new CR you could probably keep the payments under $500/month.

You might be able to find a C6 for similar money, but you might have to keep it stock or very near stock to afford it.

Either way: Reliability? check.

I'd almost bet that on cradle-to-grave costs for the car, you'd end up about the same after 5-7 years. But your payments would happen monthly at scheduled intervals instead of whenever the car leaves you stranded because of a worn or broken part.

 

One of the members in the Upstate New York area did just that - he sold his S and built an LS1 FD. The build thread can be found here, if you want an idea of what you'd be getting yourself into:

https://www.s2ki.com/forums/index.php?showtopic=464581