I searched and read some good posts like this.
https://www.honda-acura.net/forums/s...ighlight=turbo

I was originally swap H22a to my Acura 1.6EL(EK civic) but changed my mind to boosted B18.
People say LS engine is better cuase of the lower Compression Ratio and it's cheaper. But what if I get GSR engine and lower compression Ratio pistons and build up the engine. Isn't it alot stronger(power and reliability) than LS engine, it just costs some more $$. Is it even necessory to lowerer CR if I'm buiding up the GSR engine( piston, rods, gasket, engine management)?

 

It all depends on what you desire out of the car.

GSR + stock internals + stock CR + properly-installed turbo kit + hondata = reliable 8PSI daily driving.

Go with the GSR motor if you can afford it, most definitely. Small boost and high boost will both yield better numbers.

 

I want some high boost like 15 - 20psi.

 

OK before you decide you want a ton of boost or whatever--how fast do you want the thing to be and how much power do you think you need to get there?

 

Hoping to do low 12s.

What does a heavy Civic(mine) with a stock GSR motor do? Med15?

 

GSR's with i/h/e are capable of running mid-high 14's, I would expect similar or slightly better results in the EL (I'm not sure how much the thing weighs but I doubt more than a GSR).

If you want to hit 12's it's essentially not going to happen on street tires. Realistically speaking, you have a front wheel drive car with an open diff. Now if you want to just get any sort of 12-second timeslip you could probably pull it off with around 240 hp at the wheels and some slicks combined with a good launch. To get into the low 12s range however, you'll need much more than that.

I mean, do you realize just how fast a low 12-second car is? That's like Z06 and Viper territory. To accomplish the same thing in a front wheel drive car with less than half the displacement with skinny tires is a helluva lot harder.