Flirting with going high-comp on my turbo motor. Experiences?
 

I've searched a lot and seen a lot of opinions, but not a huge number of actual examples, especially recently. Sorry if this is a "duplicate", but there just aren't a whole lot of threads out there and I want to see if there is any new thinking on it.

Background - 1991 turbo. S4 irons, s5 rotor housing, FD internals, doweled. Rebuilding the engine after a particularly bad misfire cracked an apex seal. Motor was 3mm, and I've decided I'm going with 2mm seals on the build, so I've got a clean slate for rotors. I'm thinking s4 NA, 9.4:1. Running a GT35r (T4, 1.06 a/r) on a FD HKS cast manifold (extra T4 flange to make it fit). Running 50/50 water/meth injection (nozzle size TBD). I will probably be using Goopy seals since I like the extra detonation protection, and drive the car at most 2-3k miles a year and have no illusions of this motor lasting forever. I am open to suggestions, though.

My goal with the car is to have something that is fun to drive on the street, but can also drive on the track (road course or drag) for fun, not true competition. My previous car was a half-bridgeported beast that didn't come alive until at least 4k rpm, and could scare the piss out of anyone who rode in it, myself included. I want this car to be almost the opposite - quick and easy to drive with good response, but not designed to beat a corvette in the straightaways. 350-400 hp is the sweet sport I'm shooting for, maybe 450 with a good tune.

I know a lot of people say 350 is the most for a high comp turbo motor. Then there are some people making well over that. Thoughts?

Fire away!

I don't have any experience with anything other than high compression rotors. I am making well over 350 hp. Auxiliary injection and/or E85 make this very doable.

My previous setup was a stock s4 6 port block with a greddy TD06 turbo kit, running 14 psi, all the bolt-ons, no water meth, street tuned on an rtek, similar setups I saw made around 350WHP. I loved the setup. it was super responsive, full boost by 3 grand, better low end power than any rx7 i've ever driven, way more than enough power for the streets. I only replaced it because of a failing coolant seal and figured I would build a motor ready to make more serious power this time around.

doing the same thing with a fully built and balanced NA motor.. going turbo.. Knowing Im only going 10 lbs, I think a great tune and all accompanying accessories, you should be fine.