i have a 93 civic coupe ex with 250,000 miles. its my DD and i love this engine but i feel it doesnt have much left. its a new distributer, timing belt, water pump, I/H/E. so i was wondering what do i have to do to it to bring back to how it at least felt like when it had 100,000miles? i also want some power.
can i boost the engine with this many miles?
would it be cheaper just to get another d16?

 

well I had a 93 Ex Coupe with around that in mileage, it needed a lot to make the engine reliable. I called up Steve at Hmotors and just bought a d15b for 550 and was all set.. by the way.. the motor he shipped to me looked like it had no more than 20k miles on it.. beautiful for a single cam and 130 hp.

 

bore it, new rings and pistons(higher compression ratio) tune it, plus other goodies like IM, cam and youll have probly close to 150ish at the crank.

i personally would not boost a motor that has that many miles on it without rebuilding it first. for that, id put new bearings, pistons(might as well bore it while ur there), and rings in it........leave the compression the same. boost it on 5-8 psi with a small-medium size turbo....and as long as assembly is correct you should have something like 175hp(5psi)-205hp(8psi)(there are other variables involved but a general rule is that 1psi of boost is good for about 10hp) at the crank and it should still get good mileage and hold together just fine. ive heard the stock D16 bottom end is good for about 250hp so you wouldnt be pushing the limits there.

the biggest factor in having a reliable boosted engine is the tune............get it tuned on a dyno, by a reputable tuner and it should last, the second most important thing is assembly.

if you want a reliable DD with some better(not a whole lot) performance then you can do some N/A upgrades to the D16. if you want a significant increase in power then you need to boost the D16(or swap in another one in better shape) or swap in another engine series.

hope this helps