I answered your question in the pm i sent you. It might not be the answer you wanted, but its the truth.

There is no magic number. I ran my stock B20 for 3-4 years (daily driven and delivered pizza with it and ran high 11s at the track while i drove it to and from the track) at 1 bar (14.7 psi) with a t3/t04b 60-1 and had no problems. I got bored and upped the boost to around 18psi without changing the tune and ran it for a year or so till i burned up my piston rings.

The amount of boost the B20 can handle depends on the turbo size, how much fuel you have available, and who is tuning the car.

 

fuel and turbo are not my limiting factor at the moment. right now its the depth of my wallet and the size of my balls that are keeping me at 10lbs. i am not brave enought to turn it up with the stock sleeves. i might one day though. i want to reach the 400 hp mark. i think 14lbs would get me there.

 

Reliability is inversely proportional to how hard you beat on something. If you wail on a stock B20 the same as many people wail on a B20/VTEC, either one is going to fail. Reliability problems are usually caused by abuse, and there is no reason that a B20/VTEC should not be any less reliable than either the B20 that the block comes from or the B16/18 that the head comes from.

One thing is certain though: You'll make more power with the VTEC head, and the B20 head is pretty poor for flow. Really your only cash outlay will be for any conversion parts/lines that you need, and tuning. You should have everything else you need already if you're using a B17/B16 combo right now. You have the B16 head, why not use it and get all of the benefits from it?

 

that setup is still running and pulling strong as hell with no smoke whatsoever