You’re asking noob/NickAlero questions pertaining to “boost”. 15lbs of boost on a HTA86 and 15lbs on a .50 trim are two different things. 15lbs on a K20z1 with it’s 11.0:1 compression vs. that 15lbs on a stock GSR B18c1 is going to produce different power and have different reliability.
The K series motors are pretty strong stock. There’s guys making 500whp+ on stock K20a2/z1’s and K24a2 bottom ends w/ K20a2/z1 heads and are reliable. Shit, my old K20z1 swap in my EG took a 100 shot of nitrous for a LONG time before something happened with the timing in the tune, and even then the bottom end was fine. I did Wiseco pistons and Eagle rods in that and that’s all you’d really need to do to one of those to have it be reliable. Definitely under $1,000 for the pistons & rods, then new bearings and any machine work you’d need to have done. You’d need to factor in the cost of K-Pro as well(~$800) which is a must need for tuning a K series.
Edit:IMHO, this car would be retarded and almost not even fun with a turbo K series.
Quoted for truth and my opinion as well. Car is so damn light that 250NA Hp in this thing is going to fucking rip and have great drivability to boot. Keep weight down and keep the car balanced with nominal power and it’ll probably be the most fun you;ve had in a vehicle ever.
I am a huge fan of, what I dub, “shitbox” cars like this.