specifically the vitara d16z6 build.
Got my z6 out of my wrecked eg ,waiting to be worked on.

 

if tuned and built well, and well maintained, you can get near-factory reliablility....but its also about how hard you push it.

 

i had great luck with my vitara build. put about 10 thousand miles on it in the year i had the car. never had an issue with the motor. was making between 240 and 275hp with it, just about daily driven, around 10 passes at the track. i did go 75.5mm and had the pistons and block at the machine shop bored out to achieve .0035" ptw tolerence. ran it with arp headstuds and eagle rods, stock head. my ONLY gripe is that you could tell it was sluggish out of boost(i even bumped timing a few more degrees), so most of my time in vacuum was spent driving around at like 5-10" instead of 15-20", and gas mpg suffered, ususally in the mid to high 20mpg range

 

Anything above 230 whp reliable with a d, I'd be statisfied seeing as I would use it as a daily and on weekend go to the pike for some street action.

 

that's about as far as you can get is 230whp. anything after that is very risky

 

d16z6 is the most reliable honda engine!!! i made 497whp with stock sleeves sliping the clutch

 

i think this is the best statement in here to base off of. it is very dependent on a few things; build specs, turbo size, and the tune.

 

nice! can you list your setup? what clutch are you running slipping at 497?

 

It will be as reliable as you build and tune it and as strong as its weakest link. So put some thought and research into it!