Jump to content
The mkiv Supra Owners Club

Gearbox strengths


Guest suprawannabe
 Share

Recommended Posts

Guest suprawannabe

Guys a quick question as been searching but not found anything that helps yet and not 100% sure where to look. Is there any detailed info on here that states roughly what power and torque the gearboxes will take before mods required. After info for the TT and NA for manual 5/6 and auto box options. Also is the autobox different from the NA to the TT. SOrry for the nebie questions but looking at a few options and this info would be reet useful.

 

Cheers in advance.

Link to comment
Share on other sites

IIRC the Auto box is good for about 450rwhp

 

use this as a benchmark, its going to be the torque being put through the components thats going to make it fail in the end!! basically the harder the box works the hotter the transmission fluid gets so cooling is vital if your thinking of using an auto!

 

the w85 manual N/A box I would'nt fancy running higher power on, I would say its russian roulette time if your using it, although some member are and there holding up fine!

 

the 1jz r154 box (5 speed) is slightly stronger and should hold a very mild power upgrade, the getrag 6-speed box is almost invincible if maintained, the clutch being the week link and is the way to go in my opinion!!

Link to comment
Share on other sites

what caused this, lack of oil ?

 

No, it had been changed by Toyota 3 months prior to the incident, and judging by the amount of oil that went everywhere it was full, after a good examination, a gear had decided split in two and blew a hole straight through the bottom of the gearbox!, took pictures but can't find them!!

Link to comment
Share on other sites

Really?? What models? I never knew this

 

Also where was your new one sourced from??

 

The same FAMILY of Getrag 6 speed is used, but it has different ratios, different bellhousing, different input shaft, different tail shaft and other differences, so it is NOT a swappable item.

 

Whilst a given gearbox MAY hold up under say a torque rise of 20% for a while you can rest assured that it won't like it, wear will increase and it could suffer catastrophic failure. To say that the stock box is "good for" 1000 BHP is patently ludicrous.

Link to comment
Share on other sites

Chris what are your views when it comes to using the getrag on a mild single application on a supra?? surely a smallish single gt35r or similar would not overpower the box? How would you set the car up for the power say for a track car/road + race, not a car being ragged up a drag strip and holding huge burnouts on the clutch every 5 mins?

Link to comment
Share on other sites

It will handle it, but like any transmission, increase the torque or the rpm's and it will wear faster or eventually break. It's a strong box, with a lousy gear shift quality, if I was pushing more torque through one I'd use a different oil in it. But it would be MY box and MY problem if it failed ;)

 

I put near double the torque through a Hewland LD200 transaxle, but i life all the gears religiously, and the CWP, and the life is in terms of about 3 hours running time on the intermediate gears and CWP, and first gear gets changed every 5 race starts. The car should have a much stronger transaxle, but weight was paramount, and the LD is a very light transmission. i have only had one failure, and that was when I had to use a 3 rd gear ratio that should have been binned on its hours run. So, you take a gamble, but used like a Christian, with no race starts, it should handle a small single, with no real risk of total sudden failure, with luck.

Link to comment
Share on other sites

This car is for the drag strip I take it??

 

Yap :D :d

 

The yellow one has had NO expenses spared from a full race head to the bottom end . The turbos the intake the motec etc etc etc . If there was something to add i told them to put it on !money was not a issue when you go such lenths. On if it makes a 1000hp ?? well no i does not , it makes a hell more than that:D :D . And to see it on a uk dyno ?? the speck list tells its own story , It has all the wish list and more.

 

The new car will be just a Drag car :D

Link to comment
Share on other sites

Yeah.. Titan have no idea when it comes to Supras do they :innocent: :blink:

 

Lol, thats not what im saying, what im trying to say is that there is always loads of talk that yank dyno's read different to uk dyno's.

Eveyone on here is always saying dont belive yank figures:search:

I for one hope the car does make over a 1000bhp Baz, good luck with it:)

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.