Efficiency swaps in 96–00 Honda Civic CX or HX
 

Has anyone done any efficiency swaps with 1996 – 2000 Honda Civic CX’s or HX’s?

It is my understanding that the legionary Civic VX got split into two different cars.

1) The CX retained the small hatchback with the efficiency transmission, but it shares the same engine as a DX and LX.

2) The HX retained the lean burn future (in 1.6 liter form) but was put in a 2 door Coupe and shares the same transmission as the DX and LX (possibly others???)

In any case, I currently have both cars and was wondering what effect they would have if they were every combined?

Have any 96-00 HX owners swapped in a VX or CX transmission into their Coupes?

Or have any 96-00 CX owners swapped in a HX engine into their Hatchbacks?

Or has anyone done this swap HX/CX swap in anything else?

I am pretty excited about the potential swap and also looking forward to swapping over some of the HX’s “luxury” features. (i.e. power windows, locks, wheels, armrest, (wiring for mirrors but both will be removed.) Especially when there really is no cost to doing all this as I will be putting the HX back together with all the leftover parts and selling it. Just the cost of my time, which I enjoy doing this stuff as a hobby so it’s a win win!!!:thumbup:

Anyone? or do most people just sell the cars and go after the VX platform?

I have officially started to swap parts over from the HX to the CX. My CX now has a center console with an armrest! I know its trivial and a simple swap, but hey, comfort is worth it!

If I was doing any regular highway driving I would be shopping for a CX/VX transmission. As it is only one point on my commute takes me to 55 mph, which is the perfect top end for my DX - 2100 rpm.

The majority of my commute is 80% + highway. Taking backroads would more than double my communte and I can not afford to give up that much time. I love the hearing of the CX, just really wanting the lean burn 1.6 in the CX too.

Sorry I missed this!

Lean burn would be one thing that would benefit the CX for your mode of driving, but two things you need to think about carefully. First, I think you re mistaken that the CX had taller gearing than the HX. Best indications are that the sixth gen CX Hatch and the HX had the same 5th gear and final drive ratios. Also, I believe the coupes have lower drag than the hatchbacks. Finally, the HX got the lightweight wheels, whereas I think the CX got steelies (about twice the weight).

If all or most of the above is correct, you are better off modding the HX with mods like a power steering delete and aero mods--all of which might make it easier to stay in lean-burn longer and at higher freeway speeds.

Is there much of a difference in the condition of the two cars?

No problem. I am pretty sure I am right about the transmissions. Feel free to check it out. I bought my CX from the original owner with a bad input shaft bearing. It still ran and drove fine, just ridiculously loud. It was the original transmission as well as the clutch. Having owned several DX and LX civics before, I can say without a doubt this has the VX highly geared trans. In fact I actually replaced the trans with one from a 94 VX. It drives identically.

I plan on improving the areo of the hatchback by adding a Kammback or a tail. Probably Kammback for the short turm.

I just sold a set of VX wheels I had been using. Those wheels were ok, but I dislike the options for 13 inch tires. If you did not know both the Honda VX and HX wheels were both manufactured by Enkei (stamp is on the inside of the wheel.) I am now trying to decide what wheels to use. I have the 14 in HX and some 9.5 lb 15 inch enkei RPF1 wheels. So now I am weighing my options. (sorry bad pun)

As for the condition, I will post pictures later. As stated before, the CX came from the original owner and was 100% stock. It was well maintained and garaged it whole life and still has glossy red paint. Also rust free which is pretty rare over here. I am pretty partial to it.

The HX I bought from the second owner. It is pretty clean but not maintained as well. Completely stock with some rush on the rear quarters and above the windshield (which is odd.) It is also red, but has faded due to being stored outside.

I guess a 3rd option would be to pick up a blown engine sedan and swap over the HX engine with a VX/CX trans into it. Reason being, I have a 4 month old and the car seat would be easier to deal with. Then keep the CX as is as a extra vehicle.

If you have a 5th gen VX (1992-1995) trans in your sixth gen CX (1996-2000), then you do have very good gearing: it should be 3.250:1 instead of the HX's 3.750:1. Swap that VX trans into the HX and use your 15" lightweight wheels and you will have highway cruise gearing taller than the original VX and approaching the 4th gen HF. You could put a Kamm on the HX much more easily than you can swap that HX engine into the VX. But I understand the passion for the better looking car, so if you feel confident and can spend the time, go for it. Have you studied aerocivic's mods to his CX/VX? You could do a lot. Also 3wheeler's insight boat tail -- both are amazing pieces of work.

Yep. I have a 5th gen VX (1994) trans in my sixth gen CX (1997). I bought it for $150 on CL and it is great. It performs the same as the CX did with the factory 6th gen CX trans but without the bearing noise. Both ran 1700 RPMs at 55 mph. in my opinion, they are the same transmission. I think there is a lot of misinformation on the 6th gen CX gearing on the internet. Probably becasue there are so few CX's and the majority of them get swapped with a faster engine and trans. There are also many debates on what the differences between a DX and CX hatchback. The CX is lighter and gets much better gas mileage. The trans is the main reason why.

I still have the old CX high geared transmission. If there is a way to identify them as high geared, just let me know. I was hoping to rebuild it and swap it into the HX first. It might be more cost effective to pick up another used 92-95 VX trans though. Swapping the transmission takes very little time and would be a good test of the cars efficiency. Then when I have more time, I will swap the entire dropout over to the CX.
I have been a long time lurker on this website. I joined back in 2008! I have followed both of those cars for quite some time. In fact, 3-wheelers car is actually the desktop picture on my computer. lol

That's a surprise. Very nice.

Sounds like they are... that's the ~20% reduction from the DX 2100 rpm @ 55mph I expected. Would you get the part numbers off them for me, especially the 6th gen CX? I have been shopping for a VX transmission without luck for a couple months. I have a final drive from one, and I want to pull my DX trans and play around with swapping the final drive, but I would like not to lose my daily driver and so I need a second transmission. Part numbers would be way cool.

Very interesting. This suggests Honda broke up the 5th gen VX exactly the way you suggested earlier. I get it now. The CX became a cheaper higher FE car at the cost of "performance" while the HX with VTEC-e and shorter gearing (though still kinda tall) was the costlier way to FE with somewhat better power.

Great skill and patience 3-wheeler has. Nice work.