View Full Version : new 2zz gear ratios??
GTS LAID
04-26-2002, 01:17 AM
what do gear ratios like this mean to you??? higher top speed, easier to stay in lift, faster 1/4 times, better suited for low speed auto-x .. what do you guys think
Ratio /2ZZ-GE
1st: N-3.166 C-2.929
2nd: N-2.050 C-2.176
3rd: N-1.481 C-1.7
4th: N-1.166 C-1.364
5th: N-0.916 C-1.167
6th: N-0.725 C-0.916
N is Normal c60 gearing and C is the C-ONE tranny
Phil C
04-26-2002, 06:43 AM
Let's see. In order of your questions:
Higher top speed: No change in top speed as the GT-S hits top speed in 5th and new 6th is the same ratio as the existing 5th.
Easier to stay in lift: Yes. Someone should check my math because I haven't had any caffeine yet this morning. This is an easy calculation to do...Existing 1st to 2nd shift: 3.166/2.050=~1.544. Shift at 8300: 8300/1.544=5375RPM. New 1st to 2nd: 2.929/2.176=~1.346 Shift at 8300: 8300/1.346=6166.
Faster 1/4 mile times: Very doubtful. All of your gears are going to run out sooner. IMO you'd be much more likely to spin off the line and ruin your 60' time and you would be probably be grabbing fifth gear at the end, one extra shift makes a much slower run.
Auto-X: Doubtful. In my experience this might lead to needing to shift to third in many courses which would be a real problem. It's one of the major reasons the SE-R Spec V is not considered a good autocrosser. Also keep in mind that this would bump you into a prepared or even a modified category, I don't remember which and don't have my rule-book here, and you'll get stomped.
What it would most likely do is crap out your gas mileage pretty nicely, essentially you no longer have a sixth gear for highway cruising. it also seems to me it would be cheaper and easier to change out final drive gear ratios instead of the whole transmission and you could achieve almost the same thing.
GTS LAID
04-26-2002, 06:51 AM
That useless huh??? hehe... thats what i thought... but i figured there must've been some kind of good ol' japanese ingenuity involved. guess not !
autxr
04-26-2002, 07:54 AM
Useless?
No, most certinaly not.
On a road course, those gears would rock.
The lower first ratio would make launching harder, and you would have more time before lift, so that would hurt a drag race, you would probably still finish in 4th gear, so there aren't any extra shifts (you would be at redline in 4th).
Kind of a wash, so long as you don't need 5th in the 1/4 mile (95 mph in 4th).
They would hurt gas milage.
Intersting if you look at those gears...
Stock 5th has been moved to 6th.
Stock 4th has been moved to 5th.
Now, order up a 3rd gear set from a GT (1.39), that is almost no difference from the C-one 4th... (the GT 3rd would make the top speed in 4th 93 mph rather than 95)
This leaves the C-one 1-3 as the "special" gears. Of course, if you plot it all out, 1-3 in the C-one set are just perfect...
Honestly, if I have my Celica long enough to prep it as a track car, I will probably look into the C-one gear set, even if it is $2000. It would make the car that much faster around a race track.
Scott
GTS LAID
04-26-2002, 08:02 AM
damn you guys thought i was clueless before now i'm really confused...
Auto[BoT]_GTS
04-26-2002, 08:25 AM
hhaha my brain hurts that looks like jibberish
NSX_GTR_LM
04-27-2002, 02:37 AM
Having those tighter gear ratios will definitely give you better overall accelleration. Your car wont be "geared" for 0-60 anymore, but:whogives: That would totally tear sheeit up on roadcourse. I completely agree with everything scott said.
t2000gts
04-27-2002, 09:11 AM
um...does the final drive stay the same?
if it's still 4.529:1 for final, then you'd have pretty bad gas mileage, it's like losing the current 6th gear.
otherwise, it's got the perfect balance just about.
1 and 2 have been made closer together so you can stay in lift for 1->2, 1st runs to 45mph, 2nd to approx 60mph, 3rd hits lift at 55mph around, so you're still easily in lift. and 3rd runs to 77mph, still enough because 4th hits lift at 69mph, so way into lift still...and 4th runs out at around 96mph, which is ok cuz 5th hits lift at around 81mph, so...damn. that runs to 112mph around and the new 6th hits lift at 103mph so that's still easily in lift...and 5th tops out at 143.
basically, they threw out the overdrive gear for highway cruising and moved the other ratios around to be more aggressive.
i think you would get a faster quarter mile time from this gearing if you launch well (near 6000rpm in first, so the taller first won't make much of an impact) and shift really fast (cuz of the extra shift to 5th at the end). i don't know about trap speeds, might be around the same. it just pulls harder.
best way to compare is that cartest program's gearing graph.
to put it in a nutshell
0-40: old GTS gearing has advantage but not much if you can launch well
40-45: new gearing by a lot
45-55mph: new gearing
55-65mph: old gearing by a lot
65-77mph: new gearing
this next part is key where you think the old gearing might come out on top with a BIG advantage:
77mph-87mph: old gearing by not much
87mph-97mph: new gearing by a lot
97mph-115mph: new gearing BARELY
115mph-140mph: dead even
0-60 times get hurt a little, everything else improves.
PorkchopSpecblue GT-S
05-01-2002, 01:56 PM
Does this c-one trans actually exist??
C-one gear ratios...whatever, is it out there?
Blue Bomber
05-01-2002, 02:25 PM
http://www.c-one.co.jp/C-ONEPARTS/cross_mission.html
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