Custom Transmission

[WillyK]

Would this be possible to do? Get a whole transmission custom made for the celica with better gear ratios and its stronger (no stupid syncro problems) Where would I even go about finding a place that could do it and how do you think something like that would cost? Thanks.

[autxr]

Figure $5000-10,000

[oldster]

Originally posted by autxr
Figure $5000-10,000

The cost for engineering time will probably exceed that, then you have to machine and manufacture the parts. That concept would be a megabuck undertaking. IMHO

[WillyK]

YIKES!!!

Thanks for the replies fellas...I appreciate it.

[t2000gts]

quaife can hook you up custom 6-speed tranny built to take abuse plus all custom gear ratios. you have to order a minimum run of 20-25 units i think though...so you need 20-25 other celica owners buy it with you.

[oldster]

Originally posted by t2000gts
quaife can hook you up custom 6-speed tranny built to take abuse plus all custom gear ratios. you have to order a minimum run of 20-25 units i think though...so you need 20-25 other celica owners buy it with you.

At what price?

[ishido]

hehehe, one way to test out gear ratios
Gran Turismo 3 on PS2

Seriously though, I tinkered w/ some custom ratios to keep all gears in 6K and they all had to be shortened dramatically. Shortening 2nd gear caused 3rd to fall short, so 3rd needd to be trimmed. The result was a car w/ some seriously close ratios, but w/ some sacrifice around the virtual track since the 6K boost was full on in every gear.

I did compare the ratio numbers in a magazine to the numbers in the game and they were accurate. Actually the game was more accurate as it went to thousanths (.xxx) vs. hundreths (.xx)

Just some fun tinkering. :p

[Jesse IL]

Quaife will make custom ratio GEARS, not the whole box. They will do whatever you want, but the minimum production run is 25 sets. They sell a Honda B16/B18 trans set for around $2500 list. The reason for the high cost is the high cost of the gear hobs necessary to machine the gears. Hobs like that would run roughly $1000 a piece and the trans might require 2-3 different hobs, plus materials, heat treating, other surface treatments of the gears, finish grinding of the teeth... Then the synchros require another special tool to make.

[oldster]

Originally posted by Jesse IL
Quaife will make custom ratio GEARS, not the whole box. They will do whatever you want, but the minimum production run is 25 sets. They sell a Honda B16/B18 trans set for around $2500 list. The reason for the high cost is the high cost of the gear hobs necessary to machine the gears. Hobs like that would run roughly $1000 a piece and the trans might require 2-3 different hobs, plus materials, heat treating, other surface treatments of the gears, finish grinding of the teeth... Then the synchros require another special tool to make.

Thanks for the information.

[t2000gts]

actually, they do make custom FWD 6-speed racing transmissions in addition to gears. it's a sequential tranny with a buncha little extras (like gear indicator light hookup).

www.quaifeusa.com

i think you need minimum 20-25 unit run on both trannies and gears. the transmission will obviously cost a helluva lot more.

[vvtlikick]

On the TRD Japan Website (http://www.toyota-trd.com/en/comp/drive.html), there are <b>3</b> different gearsets listed for the C52/C56 transmission (Doesn't the Celica 5 speed uses the C56?). For the C52/C56 trannies, the price is "Made to Order" but it hopefully isn't much more than the other trannies gearsets, which range from &yen;140000 ($1100) to &yen;210000 ($1670). They also offer two alternate final drive ratios for the C52/C56 trannies ("Made to order" and $780 for those two, respectively).

And if you were going for all-out performance, it would be worth it to put one of these close ratio 5 speeds and the shorter final drive in a GT-S, but driveability/economy would suffer.

[t2000gts]

and if you were running a turbo or s/c or something, you might wanna look into a slightly taller final drive to utilize that power better (less traction problems under 60mph, improved top end).

[WillyK]

You are guys are full of info, thanks for it. What about just getting stronger syncronizers for the gears? Or do the syncros come with the gears automatically? That is my biggest complaint with the celica is the syncros wearing out. I worry about what this car will be like 5 years down the road or whenever when the warranty is long gone and the syncros are still crapping out in it.

[Dealer Xing]

You don't necessarily have to shorten each gear, just change the Final drive.

[Jesse IL]

The synchros are a separate part and have to be made softer than the gears in order to perform their function without damaging the gears. Stronger synchros is what is mostly needed on the Celica. Shortening the final drive will make the gearbox behave more like a close ratio box, but will not affect the RPM spacing between gears. This would require closer gear ratios. I've recently come across some unverified info that Australian Celicas have a shorter final drive gear and a taller 6th gear. This would make the trans behave better in gears 1-5 but would keep 6th good for highway cruising. I am seriously looking into importing these gears if what I found turns out to be true.

[vvtlikick]

Originally posted by Jesse IL
The synchros are a separate part and have to be made softer than the gears in order to perform their function without damaging the gears. Stronger synchros is what is mostly needed on the Celica. Shortening the final drive will make the gearbox behave more like a close ratio box, but will not affect the RPM spacing between gears. This would require closer gear ratios. I've recently come across some unverified info that Australian Celicas have a shorter final drive gear and a taller 6th gear. This would make the trans behave better in gears 1-5 but would keep 6th good for highway cruising. I am seriously looking into importing these gears if what I found turns out to be true. I don't believe the Aus. spec Celica has different gearing from what I read here (http://www.pressroom.com.au/pressroom/sample/presskits/99celicakit.htm#19).

[WillyK]

OK so let's move on to the stronger syncro's theory then. Does anyone know of a place that could manufacture strong syncros? I could get some and send to a place to make new ones. Any ideas?

[Jesse IL]

Here, I just copied this off that page you linked to:

The Toyota C60 transmission has ratios of: first, 3.166; second, 2.050; third, 1.481; fourth, 1.166; fifth, 0.916; sixth, 0.725 and reverse, 3.250. It is matched to a final drive ratio of 4.529:1.

OUR trans has a 3.91:1 final drive and something like a 0.81:1 sixth gear. First through fifth are identical to that box. Going through the calculations for the 4.529 final drive and a value of 11.1 in. as loaded tire radius, I got that with this trans, 4th gear will redline at just over 100mph, 3rd between 75 and 80, 2nd around 55, and 1st at about 35.

Now all I need to do is get my hands on the final drive gears and the 6th gear from that box. Group purchase anyone?

[Kit99bar]

sweet cakes :)


UOTE]Originally posted by Jesse IL
Here, I just copied this off that page you linked to:

The Toyota C60 transmission has ratios of: first, 3.166; second, 2.050; third, 1.481; fourth, 1.166; fifth, 0.916; sixth, 0.725 and reverse, 3.250. It is matched to a final drive ratio of 4.529:1.

OUR trans has a 3.91:1 final drive and something like a 0.81:1 sixth gear. First through fifth are identical to that box. Going through the calculations for the 4.529 final drive and a value of 11.1 in. as loaded tire radius, I got that with this trans, 4th gear will redline at just over 100mph, 3rd between 75 and 80, 2nd around 55, and 1st at about 35.

Now all I need to do is get my hands on the final drive gears and the 6th gear from that box. Group purchase anyone? [/QUOTE]

[vvtlikick]

Originally posted by Jesse IL
...

OUR trans has a 3.91:1 final drive and something like a 0.81:1 sixth gear.

...Nope. The Celica 6 speed has a 4.529:1 final drive and a 0.725:1 6th gear. And I believe the same ratios are even fitted to the Matrix XR-S and Corolla T-sport.

US specs at teamunison.com (http://www.teamunison.com/tech/2002celica.html)

Japan specs at toyota.co.jp (http://www.toyota.co.jp/Showroom/All_toyota_lineup/Celica/spec/sheet.html)

[Jesse IL]

I don't disbelieve you, but do the math yourself:

Max speed in gear = [(redline x tire radius)/(gear ratio x final drive ratio)] x Pi/528

Use tire radius in inches (I used 11.1, loaded tire radius for a Bridgestone RE730 in 205/50-16 size) and you get:

97.6 mph @ 7800rpm in 4th
103.8mph @ 8300rpm in 4th

I for a fact know that my 2000 GT-S goes alot faster in 4th. Now compare these numbers to a 3.91:1 final drive ratio

113.0 mph @ 7800rpm in 4th
120.2 mph @ 8300rpm in 4th

Seems more like my GT-S to me.

[Kit99bar]

man hitting 103 mph at the top of 4th would work perfect for the track :)

[t2000gts]

i get different results.

http://subzero.mine.nu/celica/topgearspeed/