5th gear swap?

[nobodyhere671]

i'm going to put in a kia trans, but i want a taller 5th gear for better gas mileage. i checked the protege forums and they said the 626 gear would work and that the protege dx would be even taller. but then someone said it didnt work. does anyone know what 5th can be swapped into the gseries trannny for sure?

[Limegreen mx-3]

the 5gear on a kia g-series trans is a taller gear than that of the mazda g-series trans. but not my much

reason why i say that is 5gear at 3000 i was at 60mph on the mazda trans

where as on the kia trans on 5gear at 3000 i was about 70mph.

like i said not mch of a difference.

that a few things i notice since i have use boths trans kia/mazda

[nobodyhere671]

is there a 5th gear from another transmission that i could swap that would be even taller than that? because i use the highway alot and am usually goin 80-85 most of the time. by the way, since you have the kia trans... what clutch setup do you think works best with the bpt

[Limegreen mx-3]

not that i know of so i can't help u there.

the clutch i went with was a extreme act for the miata.

rated around 400 ft lbs or torque.

has done good for me. and i drive my mx-3 as a daily cause its just to much fun to drive.

and i do drive across town just to get to work m-f. i put about 240 miles just to work and home every week. thats on a kia trans. thats a lot of miles just for work.

[nobodyhere671]

the 1.8l 94-01 miata right?

[Limegreen mx-3]

yes thats right

http://www.advancedclutch.com/products/ ... =2816#2816

[Yoda]

i'm going to put in a kia trans, but i want a taller 5th gear for better gas mileage. i checked the protege forums and they said the 626 gear would work and that the protege dx would be even taller. but then someone said it didnt work. does anyone know what 5th can be swapped into the gseries trannny for sure?

I used the .67 5th gear set from an '80-81 626 with the 2L turbo. It is a complete bolt in for the G series MTX. Unfortunately this P/N# are no longer available in North America from Mazda since this parts are almost 30 years out of production. With the 4:11 final and the super overdrive 5th, I was turning around 2700-2750rpm at 130kmh. The only real problem I had was that I kept fouling plugs if I drove long distances in 5th.

There is a current production .68 ratio available in some markets outside of North America and Asia. Looking at them they appear that they will fit in a standard version of the G tranny although I have yet to take the time to test fit them.

[dutchboy]

does anyone know what 5th can be swapped into the gseries trannny for sure?

I used the .67 5th gear set from an '80-81 626 with the 2L turbo. With the 4:11 final and the super overdrive 5th, I was turning around 2700-2750rpm at 130kmh. The only real problem I had was that I kept fouling plugs if I drove long distances in 5th.

There is a current production .68 ratio available in some markets outside of North America and Asia. Looking at them they appear that they will fit in a standard version of the G tranny although I have yet to take the time to test fit them.

What's the cause behind the fouling with the tall gear? Does the engine just not like that rpm range/load?

How often did you have to clean them up? Any way to prevent/reduce the fouling by adjusting spark plug gap or type?

Would going lower with a taller Final Drive ratio just make it worse or is there a range on the low end that gets away from the cause of the fouling?

Was this in your built 2.0L zx2 motor? (think that's what it was?). Do you think the 1.6L B6 would suffer the same fate?

Dreaming of an RS with the 3.619:1 and a 5th gear swap (a .69 from a ford festiva that someone mentioned, or the .68 you are talking about). More on that on this other thread: http://www.mx-3.com/phpBB3/viewtopic.php?f=30&t=68036

[wytbishop]

wow that's almost a 4 year old thread revival.

Yoda doesn't live here anymore.

[Nd4SpdSe]

Sadly. Yoda was awesome!

People don't understand that lowering the revs doesn't mean you'll gain fuel mileage.

Fowling would come from the lack of revs and how hard the motor is working because you've divided your power even further.