JZA80 tailshaft lengths and differences

**midnight_purple_GA70** · 09-05-2010, 04:42 PM

Ok im in a bit of a situation here where i need to find some info on tailshaft lengths etc...

to summarise a mate is doing an NA auto aerotop conversion to a tt auto aerotop... the driveline out of the aerotop has been transferred into the old tt 6speed shell and car has been sold... the 6speed conversion has also been sold...

now he is planning on using the manual loom and ecu with a shift box to control the auto... after having troubles finding a tt auto jza80 tailshaft to suit the gearbox (electronic kickdown a340e) and a tt b series diff i suggested he buys my entire driveline from my soarer to slot it in...

this is the point where the trouble arises...

the soarer tailshaft is about half a foot too long between the center bearing and the diff...

so from my understanding there are the following tailshafts for the jza80 supra...

6speed tt = 4 bolt flange to gearbox and 3 prong donut flange to diff (diff flange is the slightly larger of the 2)
auto tt = 3 prong donut to gearbox end and same to diff... same diff flange as the 6 speed
5speed na = spline to gearbox and 3 prong donut flange to diff (smaller flange on the diff)
auto na = spline to gearbox and 3 prong donut flange to diff... same diff flange as 5 speed...

so does anyone know what the differences in lengths the above have... more importantly which can be used with the combination of parts already in the car... (i am having a guess that an na auto tailshaft might work but ide like to confirm this 1st before spending any money...)

**wilbo666** · 10-05-2010, 08:39 AM

My understanding is that the auto TT run a 4 bolt flange out of the gearbox... not a 3 prong donut.. I.e. as shown in the below pic taken from here: http://www.supras.nl/index.php?optio...d=35&Itemid=52

Another thing to note is that the early 6speed TT's came with B series diffs, and the later 6speed TT's came with A series diffs.

All NA's had the smaller A series diffs, and I was under the impression that all auto TT's also ran A series diffs, but I haven't confirmed that 100%.

Cheers
Wilbo

**midnight_purple_GA70** · 10-05-2010, 11:28 AM

hmmm well they might actually have an aristo tt auto box then... which i thought was the same as the supra tt auto box... grrr why couldnt they make this easy like mk3s... one tailshaft to suit all with just a varying front shaft length... all interchangeable...

**brett_celicacoupe** · 10-05-2010, 08:21 PM

i can confirm most of wilbos stuff.

also note that there is 2 sized PCDs on the diff flanges of the JZAs

the NA diff flange is slightly smaller PCD than TT6speed PCD.

just to complicate things further, the TT auto (at least in my case, GZ model) diff is an A series with the larger PCD on the diff flange.

**midnight_purple_GA70** · 11-05-2010, 08:56 AM

Originally Posted by brett_celicacoupe

i can confirm most of wilbos stuff.

also note that there is 2 sized PCDs on the diff flanges of the JZAs

the NA diff flange is slightly smaller PCD than TT6speed PCD.

just to complicate things further, the TT auto (at least in my case, GZ model) diff is an A series with the larger PCD on the diff flange.

i know there are the 2 sized PCDs on the diff flanges

to complicate things further does anyone know if it would be possible to knock the front half off the soarer tailshaft and mate it up to the rear half of the jza80 tailshaft to create one that will bolt to the B series diff with larger PCD and then mate up to the soarer auto with the splined output?

**brett_celicacoupe** · 11-05-2010, 05:47 PM

yes you should be able to.

i am using a MX83 front section onto a NAJZA80 rear section. this allows a bolt in arrangement with the R154.

you will need to swap the centre bearing housing with the supra one also (10min job)

**midnight_purple_GA70** · 12-05-2010, 09:30 AM

Originally Posted by brett_celicacoupe

yes you should be able to.

i am using a MX83 front section onto a NAJZA80 rear section. this allows a bolt in arrangement with the R154.

you will need to swap the centre bearing housing with the supra one also (10min job)

ok so ill tell him he needs to get the front section off the soarer shaft and combine it with the rear section of the supra shaft as well as swap the centre bearing over to the supra one...

thanks for the info

**manny** · 12-05-2010, 09:56 AM

JZZ30 Soarer and JZA80 Supra centre bearing are the same

**brett_celicacoupe** · 12-05-2010, 01:35 PM

Originally Posted by midnight_purple_GA70

ok so ill tell him he needs to get the front section off the soarer shaft and combine it with the rear section of the supra shaft as well as swap the centre bearing over to the supra one...

thanks for the info

you just need the centre bearing housing.

you dont actually need to change the bearing

**midnight_purple_GA70** · 12-05-2010, 01:42 PM

ah ok no worries so front section of soarer shaft and rear section and centre bearing housing off jza80 shaft... good stuff should be able to get the car up and running soon

**midnight_purple_GA70** · 13-05-2010, 12:44 PM

i can now confirm the difference between the aristo auto and the supra tt auto is the 3 bolt donut style flange or 4 bolt flange as pictured above... never actually knew there was a difference there... flanges are however interchangeable... not that it helps the current situation as we dont have a 4 bolt gearbox flange...