HX's vs EX's

[HXCivic97]

Alright, maybe I'm starting to develop a bit of a complex about my car and it's label - HX. Don't get me wrong, I love my car, and wouldn't trade it for anything. But I keep sitting here wondering... why, god, why couldn't they leave well enough alone with VTEC? Why did they have to think about the environment and gas mileage and come up with the VTEC-E? Well, here's my question.

As far as my limited understanding of the way VTEC-E works, it functions exactly the same as VTEC, except that when the VTEC is engaged and the engine goes into 'race mode' (vroomvroom) two of the valves (one intake, and one exhaust) cease to function, hence giving a little performance boost, while maintaining a good gas mileage due to the lower amount of fuel being dumped into the cylinder. Now, like I said, this is a very basic understanding of the way VTEC-E works, and I might be completely wrong. If so, please educate me =). If I'm right, however, then read on -

The EX with it's VTEC and the HX with its VTEC-E I assume have essentially the same 1.6 SOHC engine. So what is it then that makes the two valves cease to function? And the more important question... how does one instill life back into those two valves which have slept for so long in those high revs? Is it a camshaft issue? Or somehow controlled electronically?

And one more thing. Why does everyone seem to forget the HX was ever created? Seems like every header or exhaust or tail light, or head lamp, or... well you get the idea... is made for '96-00 DX, LX, EX' or whatever. Seems to me it'd fit on the HX as well! But that's just me bitchin. Forgive the rant =)

If anyone can shed some light on my uneducated mind, I'd appreciate it - and any HX owners (or anyones else who knows i guess) that can tell me if I'm right in my assumption that whatever fits the EX will also fit the HX, I'd appreciate that too.

[piscorpio]

Ok, I broke out the Helms manual just for you.

At a glance of the engine specs, I can tell you that the d16y5 (HX) head is different from the d16y8 (EX). This includes the HX having only primary and secondary rocker arms, while the EX has an extra mid rocker arm. If you are thinking of a way around this, I would have to guess the only way is to replace the HX head with the EX. Whether this is possible, or simple, I couldn't tell you.

Another point of interest, if your HX is a manual transmission version, it wieghs the same as a CX hatchback according to Helms. Just something to consider if you catch the swap bug.

[HXCivic97]

Originally posted by piscorpio
Ok, I broke out the Helms manual just for you.

At a glance of the engine specs, I can tell you that the d16y5 (HX) head is different from the d16y8 (EX). This includes the HX having only primary and secondary rocker arms, while the EX has an extra mid rocker arm. If you are thinking of a way around this, I would have to guess the only way is to replace the HX head with the EX. Whether this is possible, or simple, I couldn't tell you.

Another point of interest, if your HX is a manual transmission version, it wieghs the same as a CX hatchback according to Helms. Just something to consider if you catch the swap bug.

Definately need to get some cash flow so I can get me one of those helms manuals... I must be the only person who knows about cars as much as I do without owning one - kind of embarassing actually

At anyrate, I do have the manual version of the HX (i wasn't aware that it came in auto)... and I'm definately considering the swap (B18C5). Once again, I need the cashflow though. Damn money. haha

Once again, gonna try to spout off some knowledge from memories long ago - isn't the CX the lightest civic made? I mean, it's practically got nothin on it. And how does my coupe even come close to being that light, apart from having the 11 lb carbon alloy rims? It's got power everything, and power steering, etc, etc ad nauseum, while the CX doesn't. Hell, it's below even a DX hatch in terms of bells and whistles, right? So maybe explain to me? I always enjoy learning about my car, cuz HXs don't pop up in AF too often

Thanks for bustin out that helms btw... what a good guy!

[Ebranste]

You should search throuhg the forums a little harder. I'm an HX owner and a few others here are as well. The topic you are asking about was discussed a few months earlier and explained. Give it a search for more info on the difference between the 2 models.

Also note that simply swapping a head will not convert you to an EX. You'd have to swap the head, header, ECU and probably the entire exhaust, possibly routing some new wires to the engine bay as well.

So if you're up to this, you might as well do a b16 engine swap instead. More horsepower and more choices in aftermarket support.

[95cvccvx]

i think he might be talking about gear ratio. The cx-vx has longer gear ratio as well as the hx transmission. That helps the car improve on gas milage but hurts in performance. Also i think that the vtec like you said earlier runs on 12 valves until 3000rpm than switch to 16. That also make the car slower in speed.

[Melt]

I love HX's. If i were to get a 96-00 civic, I would most likely try to find an HX. Great gas mileage, and they have the vtec option, unlike the DX

[piscorpio]

Originally posted by HXCivic97


Definately need to get some cash flow so I can get me one of those helms manuals... I must be the only person who knows about cars as much as I do without owning one - kind of embarassing actually

At anyrate, I do have the manual version of the HX (i wasn't aware that it came in auto)... and I'm definately considering the swap (B18C5). Once again, I need the cashflow though. Damn money. haha

Once again, gonna try to spout off some knowledge from memories long ago - isn't the CX the lightest civic made? I mean, it's practically got nothin on it. And how does my coupe even come close to being that light, apart from having the 11 lb carbon alloy rims? It's got power everything, and power steering, etc, etc ad nauseum, while the CX doesn't. Hell, it's below even a DX hatch in terms of bells and whistles, right? So maybe explain to me? I always enjoy learning about my car, cuz HXs don't pop up in AF too often

Thanks for bustin out that helms btw... what a good guy!

Hmm, this wieght issue has come up before. Im just going by what it says in the Helms, which is the gross vehicle wieght, so perhaps it is a bit misleading? I would still guess it wieghs less than any other 6 gen. coupe at the very least, but that is just my guess based on the fuel effeciency focus of that trim. Oh, and the auto HX has the CVT (continuously variable transmission), which is gearless blah blah blah...

[Rice-Rocketeer]

Originally posted by HXCivic97
I must be the only person who knows about cars as much as I do without owning one - kind of embarassing actually

You should never overestimate yourself, it just sets you up for someone to knock you down. But I don't have one either so you can feel better.

If you're consdiering a swap and your financial situation isn't up to par, don't consider the most expensive engine you can get.

The Cx isn't the lightest civic made, there were 7 generations of civics made starting in the mid-70's. If you've ever seen a cvcc, you'll know what small and lightweight is.

Your rims are made out of aluminum, not carbon alloy.

The majority of a car's weight doesn't come from power accessories but from the steel frame and body panels.

I would give you a website so you can learn the ins and outs of the different types of Vtec but it's down right now. I'll work on that.

As for why Honda came out with a ULEV vehicle, because that's what Honda has always been about. They make extremely well built and reliable engines that always pioneer gas-efficiency and cleanlyness. As for why noone makes stuff for the HX, because in most every way, it was designed for fuel effieciency and not power. So it's very hard to make power adders for an ULEV vehicle and still keep everything CARB certified.

Originally posted by 95cvccvx
i think he might be talking about gear ratio. The cx-vx has longer gear ratio as well as the hx transmission. That helps the car improve on gas milage but hurts in performance. Also i think that the vtec like you said earlier runs on 12 valves until 3000rpm than switch to 16. That also make the car slower in speed.

No actually both have some of the shortest gears of the civics in thier generations because thier engines don't make much horsepower. So the short gears help bring more of the limited power out earlier and help the car feel a little less lethargic than it really is. And the 12 valve action actually helps low end power by swirling the intake charge a little more and that inturn helps the atomization of the mixture and that helps give the Cx engine its 90lb of torque at an impressive 2000 rpm. But I'm probably boring you now so i'll stop.

[HXCivic97]

You should never overestimate yourself, it just sets you up for someone to knock you down.

Um.. ok Don't really know what you're referring to, but that's cool.

If you're consdiering a swap and your financial situation isn't up to par, don't consider the most expensive engine you can get.

Yeah i know - everything right now is very very long term. I've been planning and learning and figgering out what I want to do for a year now without even touching my car, except putting a short shifter in there. Just hanging out until I have the money to do what I want. Not gonna settle for anything else. Whether what I want is the B18 or B16 or anything else, I haven't really decided. As days come and go, I change my mind often. So until I'm sure, I'm just hanging out.

The Cx isn't the lightest civic made, there were 7 generations of civics made starting in the mid-70's. If you've ever seen a cvcc, you'll know what small and lightweight is.

I guess what I said was a little misleading. I meant for any given recent generation in which the CX was offered, isn't it generally the lightest and whatnot. Whether that's accurate or not, I still don't know. But seems to make sense to me.

Your rims are made out of aluminum, not carbon alloy.

No, I'm pretty sure they're alloy. I'm pretty sure cuz that's the option I bought it with.

The majority of a car's weight doesn't come from power accessories but from the steel frame and body panels.

Yeah I'm aware of that. But my understanding was always that coupes or sedans are almost always heavier than hatches. I was simply pointing out that with the added bells and whistles, it didn't make any sense to me whatsoever that it would be the same weight. Once again, I'm not sure of that, and readily admit to my lack of knowledge on the issue, but I was just following my logic, wrong as it may be.

I would give you a website so you can learn the ins and outs of the different types of Vtec but it's down right now. I'll work on that.

I'd really appreciate that =) pm it to me as soon as the site comes back up - i"ll be looking out for it.

As for why noone makes stuff for the HX, because in most every way, it was designed for fuel effieciency and not power. So it's very hard to make power adders for an ULEV vehicle and still keep everything CARB certified.

Yeah makes sense. I guess what puzzles me is that as far as the block goes, the EX and HX are nearly identical, right? both D17 series. So I guess I'm curious why a header which fitx an Y8 block wouldn't fit a Y5 block? Are there actual size differences? Or is it not a matter of fitting, really, as it is that those parts simply weren't designed for the D17Y5's different tuning, and therefore wouldn't benefit it as much?

Like I said before, I'm definately seeking to learn as much as I can, and I'm trying to suck as much nfo as I can out of you guys. I just hope I'm not pissin ya off with my questions and arguments. Just that that's the best way to learn for me. Teach me by tearing me down, guys - do your worst! =)

About that overestimating myself rocketeer... did you think that my 'I must be the only person who knows about cars as much as I do without owning one' meant that I thought I knew everything about cars? If so, that's not what I meant at all - I just meant that for knowing what I do know, I really should have a manual. I never try to spout off knowledge that i'm not sure about, and if I do say something that I think might be wrong, I say so, just like I did in this thread. I dunno - maybe I just took what you said all wrong, and if so, I apologize, but when you say something that makes me sound like I'm this new kid on the scene that doesn't know the first thing about cars, it really bothers me. Am I the smartest guy on AF? No, not even close. Do I know enough to do an engine swap all by myself? Nope. I know I don't know everything there is to know about cars, and its for that very reason that I come here to AF - I look up to guys like you who have this unbelievable amount of knowledge about cars in your head, and that's why I come here - because I think that I can learn the most by reading a talking with you guys, instead of flipping through magazines and not talking with anyone about what I learn or think i learned.

Anyway, sorry to go on that rant, and hope I didn't piss you off with this reply, rocketeer - You're definately one of those guys who I don't want to lose the opportunity to learn from. Later -

[Ebranste]

OK, the difference bewteen the HX and EX. Here I go:

Since the thread seems to concentrate more on the difference between the head of the Y8 and the Y5 engines, Ill start there.

As mentioned before the Y5 engine operates on only 12 valves, but up to 2500 rpm's not 3000. It does this by only using 1 pair of rocker arms on the intake side while the 2nd intake rocker arms per cylinder remain unused. At 3500 rpm's, the ECU activtes the VTEC solenoid which in turn activates the additional 4 intake rocker arms, therefore running in 'normal' mode afterwards.

As for the straight VTEC found in the EX, it operates on 16 valves normally, but when the engine reaches 5500 rpm's, the VTEC solenoid switches one of the rockers on each cylinder to an extra rocker located on the head and modifies the air/fuel ratio. To keep this thread from getting to long, I'll just say it's tuned for high rev's after that, makes a nice sound, and makes more power from that point on.

Other differences include the size of the front brake rotors, the size of the power brake booster, the aster cylinder, the ECU, location of the catalytic converter, the header, exhaust pipes, and the HX doesn't have a sunroof. But who give a rat's a$$.

The only reason anyone should get an EX over an HX is if they plan on doing alot of power mods without swapping the engine. Reason being that engine and exhaust mods available for an HX are very rare if existent at all. Why you ask? Simple. Look at where the catalttic converter is on an HX and compare it to an EX. On the HX the cat is right after the header in the engine bay. This helps the engine warm up faster from a cold start, but generally makes aftermarket headers impossible to install and useless as well casue the HX header is much shorter that an EX. Also, if you look for mods for an LX with a non-vtec engine, you'll notice the same rarity. An HX engine basically operates as a normal non-vtec engine when it breaches 2500 rpm's. It saves fuel by only operating on 12 valves(3 per cylinder) in stop and go or idle speeds under that rpm.

And that's basically the scoop there. If you plan on staying stock or doing mods that are everything but enine related, get an HX.You can still do wheels, suspension, electronics, body kits, air intake, muffler, but you pretty much have to leave the engine alone as there is almost zero support in the aftermarket world. One can still upgrade the rear brakes to disc and weight between the models is virtually identical.

I know a few guys with stock EX's, and they think I got screwed with my HX, but with the suspension, wheels, tires and other work I've done, it looks better. It's faster when I drive it hard(they have automatics), and only makes 10 less horsepower, not to mention it drives and corners like a beast. Also, I never heard one of them say they got 350 miles on half a tank before either

Hope all this helps and sorry if I ran on too long.

[Rice-Rocketeer]

Well if we're gonna technical about the weights of the 4th 5th and 6th generations, then yes it comes down to the accessories. Cause all 5th gen hatchbacks have the same steel frame and body panels. All 6th gen coupes have the same..etc. So in the 4th gen the CRX HF took the lightweight trophy. The 5th gen Cx took it as well. As for the 6th gen frankly, I haven't cared so I haven't bothered to look it up But you can check out carpoint:

http://carpoint.msn.com/vip/overview...=Home&pos=Find

for the weight that you need. They give you the curb weight as opposed to the gross weight. The gross weight is the weight of the car with it's maximum human occupancy, liquid occupancy and cargo occupancy. Basically, that's as heavy as it can safely get.

Now, if you have the stock HX rims, I can garauntee you they are not made of a carbon-based alloy. Honda never made it an option for the lowly civic. It is an alloy, but it's mostly aluminum. They were made by Enkei.

As far as the block of the HX and the EX, as far as I know, yes they are mostly the same. But they're 1.6 liter D16's. So given that they're the same block series, yes the headers are interchangable. Problem is the HX has the catalytic converter located on the header itself while the EX has the cat located further down the line past the oil pan. So putting an EX header on an HX block creates two problems, One: you remove the cat and in the process confuse your secondary 02 sensor an that'll throw a check engine light and force your engine into "limp home" mode. Two: The EX downpipe won't bolt up to your HX cat-back exhuast. So you'd need to get a full EX catalytic converter and cat-back exhuast as well and relocate the 2nd 02 sensor and THEN the Ex header will fit. You will however screw up your HX emmisions by doing that.

Finally, don't take anything I say personally. Everyone seems to do that with me. I don't know everything either, I've just been wandering these boards for 2 years now, so I've picked up a few things.

Originally posted by Ebranste
It's faster when I drive it hard(they have automatics), and only makes 10 less horsepower, not to mention it drives and corners like a beast. Also, I never heard one of them say they got 350 miles on half a tank before either

The CVT is a beautiful thing.

[HXCivic97]

Also, I never heard one of them say they got 350 miles on half a tank before either

Ain't it nice?

That's pretty interesting tho, All this stuff about the HX i was unaware of =)

But I think the stuff about the lack of aftermarket support has definately made my mind up to go for a swap... When I can get the money. Now, with all this newfound knowledge of the differences between the EX and HX trims, I'm beginning to doubt the relative ease of dropping in a B16 or 18 engine into the car. Seems like it's fairly easy for an EX, having talked to ppl who've done it... but I haven't spoken to anyone with an HX who've performed a swap - any forseeable problems there that you can think of?

[Rice-Rocketeer]

It shouldn't be much harder to swap it in, it's the same chasis.

[piscorpio]

Originally posted by Rice-Rocketeer
for the weight that you need. They give you the curb weight as opposed to the gross weight. The gross weight is the weight of the car with it's maximum human occupancy, liquid occupancy and cargo occupancy. Basically, that's as heavy as it can safely get.

Finally, a clear explanation. I think Ive heard this said before, but I just didnt understand what exactly the gross weight was, maybe it was worded funny.

Incidentally, here are the curb weights of the 6 gen. Civics (as listed in the brochure):

MT/AT
DX coupe - 2359/2405
HX coupe - 2370/2445
EX coupe - 2513/2560
Si coupe - 2612

CX hatch - 2359/2423
DX hatch - 2388/2434

DX sedan - 2339/2388 ????
LX sedan - 2410/2456
EX sedan - 2513/2562

Now something interesting has come to my attention, could the DX sedan actually be the lightest 6 gen. or is it a typo? Very odd. Now, can a moderator put this in a FAQ somewhere maybe, I think I collected a nice little reference here.

[Ebranste]

Originally posted by HXCivic97


Now, with all this newfound knowledge of the differences between the EX and HX trims, I'm beginning to doubt the relative ease of dropping in a B16 or 18 engine into the car. Seems like it's fairly easy for an EX, having talked to ppl who've done it... but I haven't spoken to anyone with an HX who've performed a swap - any forseeable problems there that you can think of?

As to the difficulty of swapping an engine into an HX, its the same procedure as an EX. Shouldn't be any different assuming your dropping an OBDII into a 6th gen Civic. I belive a problem only wxists when doing a swap into a DX or LX cause you have to run a wire for the VTEC solenoid.