98 civic ex tranny swap to lx - Fuel Economy, Hypermiling, EcoModding News and Forum

pdq54 · 04-21-2012, 08:52 AM

I have access to a civic lx that is being parted out before going to scrap. Is it worth the effort to swap my civic ex tranny with the lx for lower rpms, fuel savings?(I think the lx has taller final gearing) 98 ex final ratio is (1)4.25, the 98 lx final ratio is (1)4.058. Your input is appreciated.

MetroMPG · 04-23-2012, 01:13 PM

It depends: how much work is each 1% improvement in cruising fuel economy worth to you?

I'm not familiar with the Civic drivetrain lineup -- is there an apples:apples comparison between 2 models that shows the MPG benefit of this final drive?

I made quite a large change to my final drive -- went from 4.39 to 3.52. It made about a 5% improvement in fuel economy in my Metro/Firefly: Project 'nerd gear': taller tranny transplant nets +5.2% MPG - MetroMPG.com

drmiller100 · 04-23-2012, 11:10 PM

lots of people will trade you trannies, and maybe even do the work.

the ex trannies are desirable.

The only REAL difference is in first gear, and fifth. and of those, fifth is the only real difference, which will only make a difference cruising down the interstate.

California98Civic · 04-24-2012, 01:10 AM

Quote:

Originally Posted by drmiller100

lots of people will trade you trannies, and maybe even do the work. the ex trannies are desirable.

I second that. EXs are desirable for lots of the racer kids. Post a desire to trade on the honda forums. See who bites.

My DX also has the same final drive as the LX. Better if you found an HX (3.750?), VX (3.250), or 5th Gen CX (3.250).

AntiochOG · 05-01-2013, 01:05 PM

I've swapped a few civic transmissions and it isn't terrible, but it is a good deal of work. drmiller is right though, EX transmissions are desirable and I wouldn't be at all surprised if you could find someone with a CX/VX transmission who wanted to swap. I'd try that route first, but if you are planning on keeping the car for a reasonable amount of time, swapping transmissions would be worth it IMHO.

PaleMelanesian · 05-01-2013, 03:36 PM

What Cali said. If you're going to the effort of a swap, go for the taller HX or the even taller 92-95 VX/CX.

What kind of driving do you do? I didn't think it worth my while on my commute that tops out at 55 mph on one short segment. If you're on the interstate it'd be a huge help.