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whoever says a LS/VTEC is unreliable is totally misinformed. What happens is people skimp when building them and THAT causes the problems. The biggest things people skimp on are not really that expensive, but they do it anyway. First people try to run the LS (B18B) water pump, this pump has 19 teeth, when you need the GSR water pump that has 22 teeth. This allows better cooling at the higher RPM range where the VTEC allows the engine to go, it is a $150 part. The next thing is they try to make their own dowel pins, instead of getting a complete gasket/dowel pin set from a place like Golden Eagle. Their kit has the head gasket for the swap, a regular LS, or GSR gasket has to be modified to block certain oil orifices for the head not to leak. This leads to the other major thing, they fail to take the head and block to a machine shop to get surfaced so they seat properly. And last but not least they seem to forget to replace the timing belt, and oil pump. All these thing will lead to failure of the engine, causing people to call them unreliable. I am proof that if it's built right it will last. I have a 99 civic coupe with a JG Engine Dynamics bottom end (B18B1) and a fully built Skunk2 head from my old B16, making a LS/VTEC engine. It is running a Peakboost GT35R turbo kit, snow perfomance methanol, AEM EMS, LSD, and other stuff (too much to write) and at 40 psi it makes a little over 700 fwhp. It runs 15 psi for daily driving and makes 419 fwhp and has been this way for over 2 years. I have had no problems, except for traction, and it has never let me down. As for the power it makes, a stock GSR puts down right at 145-150 fwhp on a dyno, and a basic LS/VTEC will make around 175 on the same dyno.