Water/Meth injection

Jordo!

Well -- few things to keep in mind...

(1) The ECU will have no idea the intake temps are cooler unless it measures air temps post W/M jet. You'd be better off spraying post compressor (without getting into a whole other topic -- the W/M spray can damage and pit the compressor wheel if sprayed pre-) to cool the charge temps, but I'm pretty sure the ECU will have no way of knowing post-compressor temps without some sort of custom set-up...

(2) The actual degree of cooling afforded is debateable, and certainly less effective than a good intercooler. The major advantage is that a W/M mixture (even just plain water) is an excellent anti-detonant -- but again, if you aren't getting knock, you won't really see any benefits.

Much of the gains come from running more ignition advance (the idea being that previously running that much advance resulted in pinging), but you don't really have any reason to assume that you will see gains from running more timing anyway until the whole turbo system is installed and tuned. There are limits to how much advance you can run before you just aren't going to make any more torque...

Now, if you found that the compression ratio of the pistons was holding you back from running more boost or more timing, then maybe it would be worth experimenting with W/M -- I don't know that you want to start out assuming you'll need it, because you probably won't.

Also, if you add it in, now you have another system that can fail and will need monitoring...

I suspect that the limiting factor on this motor will be how much power the motor can make before busting a ringland just from cyllinder pressure, and W/M won't prevent breaking from overpower.

(3) W/M kits are nice if you have cramped space and no intercooler -- a bit overkill if you do have one. I ran one for some time on my old car (before I had an intercooler), and I did pick up some power, but this is because the ECU was definitely pulling timing. But... I probably shouldn't have pushed it so far, because eventually I broke a piston and had to do a rebuild

Live and learn.

I say, get the turbo on there, tune it, and then decide. If this is your DD, you may not want to push it to the ragged edge anyway, which is the other nice thing about W/M -- if you do push it close to the limit, it acts as a good failsafe for a sketchy tune (unless of course a water jet clogs or you run out of mixture...)

If you want to read more about W/M, check out this link -- cool stuff, with a long and interesting history waterinjection.info - Powered by vBulletin

Anyway, it might be less of a hassle to develop a "track tune" using, say, 100 AKI octane fuel and a "street tune" that is a little more forgiving for 91 or 93. Fewer surprises that way.

I can't say for 100% certainty without you being on a dyno, but my guess is -- none. You probably won't see any appreciable loss in whp until you creep up to 230 - 240.

Also, there's no reason to assume the engine is pulling timing unless you see it on a datalog. It probably doesn't do that until oil temps approach 280, which can get a bit risky at full tilt for sustained periods of time.

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