Crazyhorse

I'm looking in to buying a 97 civic hx. My question is will the dc sport header for the ex fit the hx? If the two engines have the same head I would assume it would work. I know both are 1.6 sohc vtec with the exception of the hx being vtec-e. Any help would be appreciated. Thanks!

steronz

the short answer is yes, it'll fit.

the long answer is that the heads are very different, as are the motors, and putting a dc-sports header on an HX is a complete waste of money no matter how you look at it. even if you're getting a rip-roaring good deal on the header, an EX head swap will cost about the same and might actually give you a gain you'll notice, instead of just making more noise and looking pretty under the hood.

Crazyhorse

Thanks man. Can a head swap be done like that? If so, what about the ecu and wiring harness as the vtec works completely different in the vtec-e? You said that the engines were different though. I have read in some reviews that if real horsepower was to be discovered to just ditch the hx engine and go for an ex/si engine as it uses the same engine mounts.

steronz

My cursory search just now didn't yield any specs on the HX pistons, so I'm not sure what compression ratio you'd end up with from an HX-EX mini-me like that. Offhand, I would speculate it would be lower than a straight-up EX motor, so the HX-EX won't be as powerful as a full-on EX, but then doing a complete motor swap and ending up with 127 crank hp is kinda silly... if you're gonna go through all that trouble, you might as well swap at the very least an LS motor or a b16, although you'll need to get new mounts and all that. The whole point of the mini-me is that it's relatively cheap, easy, and will give the car a bit more pep... nothing you should go around challenging camaros with, but it's better than nothing, and it's also better than throwing money away on bolt-ons.

wiring shouldn't change, but you will either need a new ecu or a vafc or something. of course, ultimately, if you actually want to go somewhat fast, your best bet is to sell the HX to someone who wants it 'cuz it gets 45 MPG and buy a different car. or just keep it stock and enjoy your 45 mpg until you can save up for a b18c hatch or something.

sk8rmike

.

Crazyhorse

Thanks for all your help! I'll probably just keep the HX just because of the gas. I was just hoping that throwing some headers on there would increase the exhaust flow and possibly increase the mpg a little, plus it looks pretty under the hood. I'm not looking to make tons of power, but a little wouldn't hurt the car. I mean 115 hp is respectful compared to my stock crx hf. A whole whoping 62 hp. So, just looking for a couple bolt ons to increase the flow and hp a little bit. It does have a akimoto ram air intake, I have heard of them that's about it. Don't know how good those filters are that come with it, but if you know anything let me know. Thanks.

Crazyhorse

I looked on msn.com and found out that the ex has 9.6:1 and the hx has 10.6:1 ratios (Don't know how reliable there source is). Would a mini-me swap be possible? I don't really know if the head and block will all line up correctly. But if they do it might be worth my while to spend a few green backs just to gain some hp, just for fun. Plus, with having higher compression ratio wouldn't that help hp, too? I'm not looking to race, just want that extra little grunt.

CavemanRacing

hx does not have 10.6 compression... the mini me is possible... the head and block will line up correctly... if your goin put a y8 head on there then get it shaved slightly and buy a crower 2 cam for it.. find a y8 intake manifold and buy a decent header... you will need to get the right computer also.. you will have your little extra grunt for a very cheap price as long as you find good prices.. this can be done for under 500$s

steronz

yeah, i think driveahonda is right... 10.6 doesn't seem right at all. but there's a ton of mis-information on honda-tech, and i'm sick of wading through it. some people said it was .2 higher than the ex, some said .2 lower. in any case, the difference is all in the head, 'cuz nearest i can tell the pistons are the same, which kinda surprised me.

there's a huge thread on honda-tech that i only made it 3 pages into about if the HX engine has more potential than the EX. it IS a more sophisticated engine in that it has roller rockers and a more aggressive cam lobe, but it's all detuned to make the best gas mileage. so the argument was if you swap out the ecu with a custom chipped p28 and get rid of the egr and some other crap, you should actually be able to make slightly more power than the EX. a lot of people also turbo them with much success. you can't swap cams between the HX and pretty much anything else, which sucks, but if you look real hard you may be able to find regrinds somewhere.

the only thing everyone was in agreement on is that the HX tranny sucks. so perhaps your best move would be to swap an EX tranny. although at the end of the day, i think you're best off leaving it stock. if it were a DX or an EX, i'd say mod the hell out of it, whatever, but this thing is actually very economical. You could probably sell it outright, buy an EX, and make a decent profit in the whole deal. i don't think it's worth tanking your resale value for an extra 15 hp. just enjoy your great gas milage, maybe do some visual mods to pick up the ladies, and call it good.

edit: just found out, block castings are the same, pistons are different but i don't have the specs. crank and rods are the same of course.

Crazyhorse

Thank you both for the good info. I couldn't imagine that msn was right on the specs for the hx. I though I saw somewhere else that they are like 9.4:1. I don't know I'll keep trying to find out. As far as the tranny that's fine having long gears, because if I get a turbo setup it might work out ok for me. Maybe stay in boost a little longer.