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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?

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!

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

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.

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

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.

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

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..

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.

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.

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)

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.

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.

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