So I have an H23a Bluetop (H23a VTEC) and today I found a used Drag Turbo kit for $350. How reliable would it be to low boost the stock H23a with the t3/t4 turbonetics tubro?

 

Reliable.

with a good tune.

and not stock pistons.

 

See what sucks is that the sleeves eat up aftermarket pistons and I do not want to have the block resleeved yet. I'm just looking for small power gains not anything huge. I'd be fine with 250 whp for now.

 

Search around some more. I am sure you can find some other stock builds on H23a's. Seeing that they make 200bhp which= about 170-175whp stock, obtaining 250 is not a stretch. Do a compression and leakdown test and see if the motor is healthy enough for it. Also, you will need other supporting parts such as injectors, EMS, etc...