[FuntanaS]

I was wondering about the automatic transmissions in the 8th gen verses the 6th. In my 1998 auto the transmission has 4 speeds plus an overdrive. Does the 8th gen have 5 speeds plus an overdrive? Or just 5 speeds and no overdrive?

Thanks

 

[Civak]

Alright, so for the 8th R18 automatic Civics:

5th: 0.525
Final Drive: 4.44

So the overall reduction ratio in the highest gear for the 8th Civic Automatic is (0.525*4.44) = 2.331

The 6th Generation Automatic Civics had a 4th Gear ratio of 0.638 and a final drive of 4.357.

So the overall reduction ratio in the highest gear for the 6th Civic Automatic is (0.638*4.357) = 2.780

It's irrelevant what you want to call it; overdrive or whatever. The 8th Civic has a gear more "overdrive-ey" than the 6th gen.

This is to speak nothing of the difference in the wheel diameters of the cars.

 

[Civak]

Sorry for the double post, but as well:

You are mistaken that your transmission is a 4 speed plus an overdrive.

Your 4th gear is the "overdrive" gear. You have 4 available gears.

 

[FuntanaS]

Maybe I am screwing up the terminology but starting from first gear the 6th gen shifts 4 times. It shifts through the 4 gears and then around 52 mph the torque converter locks up which feels just like another gear shift.

So my question is, does the 8th shift though its 5 gears and then the torque converter locks up?

 

[leveldowen]

Yes, the 8th gen has a five speed automatic. You might compare this to many other compacts now coming with six speeds and CVTs, and wonder why Honda opted for less gears when most manufacturers boast about how much a six, eight or now 9 speed trans improves fuel economy. The answer is quite simple, less rotating mass means less lost energy, and good old reliable 5 speed automatic transmissions cost less up front, and cost less in potential warranty repair costs. Honda has opted to improve fuel economy by producing an engine that is highly efficient throughout a wide rev range (think VTEC and variable intake runner length), instead of trying to add more gears to keep the engine operating in a small speed range where it operates efficiently.