I had water/meth injection in my last car and there is likely no way I'll ever do it again. Yes you can get better performance but the associated extra maintenance and worrying about failure is not worth it to me. At the end of the day this is a daily driver for me so there is no need for it for me. By all means don't let me talk others out of doing it to their car. There are some great systems that work well and don't have failures. It's just not for me and this car in particular for what I am using it for. Also E85 isn't an option around where I live as it's not readily available and buying barrels of it doesn't sound like fun to me either.I'm also going to recommend water-methanol injection. A guy named Gary recently posted a dyno of his 2018 Forte5 SX DTC with at Tork SRI and axle back exhaust with a JB4 on E30. He made 176 whp stock, now makes 230 whp.
BUT, in Arizona his ambient (outside temp) was 108 degrees. His inlet temps (into the intake manifold via JB4 logging) were 150 degrees!
If you drop that down to 100 degrees via water-methanol (yes you can use them together and it's not overkill), the mass air flow will increase and it will make more power, my guess is around 250-260 hp. I made this suggestion to him and he said that somebody told him to upgrade his intercooler and that data driven information I gave him didn't move him off that.
But as I said above an intercooler upgrade in of itself won't help you very much when the weather is more than 80 degrees.
The way the JB4 controls water-methanol and their map sensor adapter they make for the Stinger works on the Forte GT, making it 100% plug-n-play, no wiring up anything more than the pump and no running vacuum line for a boost source, it works by using the OBD-II stream to detect boost and use the o2 sensor information to maintain ideal air-fuel ratio.
But that is also the core of the safety systems built into the JB4. Any fault with the WMI, it will bump you down to Map 0 which is the stock tune. The beauty is it doesn't take a flash tune to dial-in your water-methanol system, you do it via the app and everybody at BMS will help you get the most of it.
Some day I'll buy something ridiculously fast again but for now the Kia Forte Gt is mildly quick and inexpensive and I'd like to keep it that way.