Why do people favor the longer geared mx6 tranny?

mxmaz · Post by **mxmaz** » February 7th, 2006, 10:25 pm

I dont get it. You accelerate faster with the sportier shorter geared mx-3 and pgt tranny. So to the guys who favor the mx6 tranny, why do you? Are you really that concerned about the little fuel you would be saving on the highway with the mx6 tranny or something?

Aston Wards · Post by **Aston Wards** » February 7th, 2006, 10:31 pm

if i'm not mistaken (and i could be) it's only 5th that is taller...., after travelling 800k's on Monday, with a loud exhaust, i would've loved a taller top gear!

fieromx3 · Post by **fieromx3** » February 7th, 2006, 10:43 pm

higher top speed to!

well the longer gears can make u benefit from it during acceleration if u have alot of power u can find urself shifting sooner than u hope as to the mx-6 tranny u dont shift as soon and u can make more use of the power you have although as so ive heard its not much taller but you can still benefit from it

Drewation · Post by **Drewation** » February 7th, 2006, 10:53 pm

i already hate how quick i have to shift with my k8 in the first 3 gears or so, i cant imagine it with a klze i think id have to shift way to quick.

hppwdn · Post by **hppwdn** » February 7th, 2006, 11:12 pm

For guys making a decent amount of power the MX6 tranny makes it easier to launch at the track.

jschrauwen · Post by **jschrauwen** » February 7th, 2006, 11:15 pm

Maz, I guess it may depend on individual's needs. In my case I had a couple of reasons for opting for the ZE tranny. First off, my MX3 tranny will be hitting 300,000kms this summer and although it shows no signs of fatigue (good preventative maintenance over last 11 years I guess), I don't relish the idea of it suddenly giving out on me on one of my longer drives. Second since it is a summer car, it tends to go on longer drives and isn't relegated to short little hops as much any more. Third, I live very close to the 401 highway (biggest in Canada), and frequent trips down that highway to visit family or to go to meets or just about go anywhere in Ontario, I'm going to spend a few hours on the 401. That said, I don't relish the future of driving at 130kph - 140kph while my tranny is singing at 4500rpm plus. In my mind, the ZE's in Japan were mated to tranny's with a final drive of 4.11 MTX and ATX or there abouts. Subjecting that same ZE engine to a much higher than normal, much higher than specified, much higher designed rpm for prolonged periods of time - to me that's just asking to shorten the life span of a ZE. For the more younger crowd, which apparently (confirmed in another thread) don't do that much long distance driving or don't really venture too far away from home, or use it to get back and forth from school or work, or live within the confines of a city where one doesn't need to travel very far to get everything they need on a weekly basis, then I can't see a need on their part for a taller geared/ final drive tranny either. Living out in the country near the biggest highway and my lifestyle says, a taller geared tranny is best suited to my needs. And like Aston said, I like to keep my hearing in tact too.

PATDIESEL · Post by **PATDIESEL** » February 8th, 2006, 2:27 am

It is only about a 300 RPM difference per gear.
Not worth the trouble IMO for that little change. It is a bit easier in 1st gear with a ZE, but other than that the shifting is about the same. Plus in the ZE unless I'm trying to accelerate fast I go from 1st to 3rd to 5th, and sometimes from 2nd to 5th if I'm pointed downhill a tad.

Yoda · Post by **Yoda** » February 11th, 2006, 2:08 am

It also has to do with keeping the the sweet spot within the rpm range and acceleration as well. Plus or minus 200-300rpms can make a big difference how the car performs. My car was fast with a -DE and 4.11 than the -ZE with 4.38. A lot of it has to do with the -DE making more torque at a lower rpm and different power curves. If it were the other way around the -ZE would be running closed to it's sweet spot on the power curve. Almost everyone that drag races a FWD Mazda seriously, is wishing for a 3.72 or a turbo friendly 3.42 final drive for the V-6.

Unfortunately there isn't as many options for the V-6 as the is for the 4 cylinders. At least with the 4 cyl you can convert to one version of the Ford MTX-75 that is compatible with the 323 (MX-3) chassis and shifter or to find a Toyo Kogyo G15-M tranny used in the 323's with the RF-T 2.0L. This tranny has a wider step between 1st and 2nd gear, 2nd to 3rd and a much taller 5th gear. (.68 vs. .80 in the G25-M) The final drive is a turbo friendly 3.41 and the one built after 2/2000 are much beefier than in the G25 used with the V-6, due to the amount of torque these engines make fron 2000rpm and up. If guys like Dave Lauzier, Sean Matthews and others had this tranny 8 or 9 years ago import drag racing would have a different look today.

If the only concern was gas milage then it would be easier to just swap the 5th gear set from the .80 found with the V-6 to the .68 gear set found in the older 2.0L (FE) 626 or a BJ 323 with the RF-T

bigtime · Post by **bigtime** » February 11th, 2006, 5:37 am

I think the klze is quite happy to be revved to 7000rpm..
my buddys' is

with the 4.39 tranny I believe in 2nd gear you would be doing about 90-95 km/h. ( about 55 mph ) at 7000 rpm..

with the 4.11 tranny at 7000 rpm in 2nd gear you would be doing about 100- 105 km/h ( about 60 - 63 mph )

So with the 4.11 tranny, your 0-100 km/h ( 0-60 mph ), should be more impressive because you only have to do 1 gear change..

The 4.11 is about 7% taller in final drive ratio and 5th gear is slightly taller also..
So basically you can rev it a little "further" in each gear and when you got such power, torque, 16lb flywheel and 10.0 compression pulling not much weight, it does rev quickly !!
Not a big difference between the 2 trannys tho ..
not worth screwing around with gears inside, just chose 1 or the other in good condition & go with it..

jschrauwen · Post by **jschrauwen** » February 11th, 2006, 10:58 am

Yoda wrote:It also has to do with keeping the the sweet spot within the rpm range and acceleration as well. Plus or minus 200-300rpms can make a big difference how the car performs. My car was fast with a -DE and 4.11 than the -ZE with 4.38. A lot of it has to do with the -DE making more torque at a lower rpm and different power curves.

I would imagine that having the KL31 cam'd ZE vs a KL01 cam'd ZE would be a factor here when comparing final drives. Wherein the KL01 cam'd ZE would hit it's sweet spot sooner than the KL31 cam'd one would. That said, by having a 4.11 final drive would mean being in a KL01 cam'd ZE's torque sweet spot similar to or the same as a KL31 cam'd ZE would by running a 4.39 final drive. Just theorizing here though.

Gro Harlem · Post by **Gro Harlem** » February 11th, 2006, 3:48 pm

My reasoning is this:

The 4.39 gearing was designed with the K8-DE in mind. Since that engine lacks torque the gearing makes up for it by keeping it in higher rev's.

My KL-ZE, having more torque, hp across the band, simply accelerates TOO fast through the gears for my car to be "fast" in the 1/4 mile.

The KL-ZE's powerband isn't exaclty flat. If it were, it wouldnt' matter if the gearing was short. But since its sweetspot is between 4000 and 6000, keeping it in that band longer makes the car accelerate faster. At least in theory.

After doing my 4.11 conversion I don't know if it was the LSD or the gearing or both, but the car DOES feel substantially quicker if I push it to the limit.

bmwm3guy · Post by **bmwm3guy** » February 11th, 2006, 6:51 pm

Quite simply even with the MX6 tranny I feel that the gears are somewhat short. I woudl highly suggest an MX6 tranny if going to ZE... Its not like the motor cant take the longer gearing, it has nearly twice the torque (not quite, but u know what I mean)

XxantwawnxX · Post by **XxantwawnxX** » February 11th, 2006, 6:57 pm

PATDIESEL wrote:It is only about a 300 RPM difference per gear.
Not worth the trouble IMO for that little change. It is a bit easier in 1st gear with a ZE, but other than that the shifting is about the same. Plus in the ZE unless I'm trying to accelerate fast I go from 1st to 3rd to 5th, and sometimes from 2nd to 5th if I'm pointed downhill a tad.

i actually go from 1st to 5th alot....2 gears is al i need lolo.

mxmaz · Post by **mxmaz** » February 11th, 2006, 9:48 pm

Gro Harlem wrote:My reasoning is this:

The 4.39 gearing was designed with the K8-DE in mind. Since that engine lacks torque the gearing makes up for it by keeping it in higher rev's.

Thats quite possible, but the pgt also uses the same tranny. The klde has pretty much as much torque as the ze, so why do you figure the pgt didnt use the same tranny as the mx6?

I personally find the shorter gears more sporty and fun to drive.

Juans_93_MX3 · Post by **Juans_93_MX3** » February 12th, 2006, 12:41 am

4.39s must be great for K8s and KLDEs because they dont have as much HP as the KLZE
However, in the end, 4.11s>4.33s
Less shifting = better times