RT142 diff in TA22

[volpe]

Let me start by noting that the BW diff in a live axle RT142 is often slagged off as being weak as (i think "poo" is the most common term!). Considering the OEM application, would agree.

However, cheapness, availability & disk rear end is tempting, along with possibility of only a bit of work required with mounting points to fit to a TA22.

Can certainly understand they would be trash under a heavier Corona or later Celica with boosted 1G or 22R, but can't help but think they should be more than OK with a lighter TA22 and low boost 2TG (i.e. generating not much more torque than a Corona's "Super Responsive" [LOL ] 2.4 EFI)????

Been lots of talk, but has anyone actually run a corona BW diff assembly in an earlier toyota?

Cheers.

[Screamn_Sleeka]

One of their issues why no one likes them is there inherent difficulty to get a LSD.
The BW might be longer than your TA22 diff, if so it wont be as easy as you think.

The disc brakes that appear on the corona Avante's can be put on most toyota diffs (most of the small diffs). Im sure its easier to adapt the brakes to your stock ta22 diff than put in a BW.

[thechuckster]

They'd be too wide for a TA22 - so if you're paying a workshop to cut down and re-weld mounts onto a diff for you, you should weigh up the cost of using a stronger donor diff.

fwiw: GTA22 (simon) on these forums has a cut-down Commodore BW diff in his TA22 with 3TGTE in it - so if budget is an issue here, then perhaps a bogandore might be a useful donor vehicle.

[yoshimitsu9]

One of their issues why no one likes them is there inherent difficulty to get a LSD.
The BW might be longer than your TA22 diff, if so it wont be as easy as you think.

The disc brakes that appear on the corona Avante's can be put on most toyota diffs (most of the small diffs). Im sure its easier to adapt the brakes to your stock ta22 diff than put in a BW.

they have 28 spline axles just like the vl turbo. they have a factory 1.0 way lsd

[Matty]

Hey guys im in the same position here as volpe, what diffs are the simplest to throw under the bum of a 22?? I know a lot of guys have spent a fair bit on diffs but im spending heaps on the motor and wouldnt mind putting something a bit stronger till im cashed up again.
Any advice is always appreciated
Matty OTA22T

[o_man_ra23]

Ok... where do I start??

Yoshimitsu, the RT142 avante which I pulled apart had an open centre diff... not sure where you get the factory LSD from?? Perhaps this was an option?? (so hit and miss if you get it)

The brakes are easily adaptable to your standard diff, or if you want to make sure it's semi strong, then you can use the RA23/RA28 diff, which has bigger axles than the early TA22 diffs. Brett_Celicacoupe gave his T series 8 months of pure hell and torture before the spider gears let go... so on a low boost 2TG, a T series in decent condition should last fairly well if you don't drive like a tool.

Bog Warmer diffs have a rear feed centre. To lash them, you need to play with shims. Unless you have a collection of these, you will have to take your diff to a specialist, and this costs big coin. Toyota diffs are banjo style, where the centre is lashed by adjusting big screws to move the bearings side to side. This can be done on a workbench at home, rather than under the car in a workshop.

As mentioned by Chuckster, they are WAAAAY too wide, so again you have a costly trip to a specialist.\

You will also have to modify your tail shaft, another costly trip to a specialist.

In short, if your on a budget, a good condition T series from an auto RA23/28 with the brakes from an RT142 avante, and don't drive in a manner conducive to breaking diffs (ie, take off smoothly, no flat changes etc) and you will have no issues with it. Heck, they will still take a reasonable few big burnouts etc, and aren't exactly hard or expensive to repair/replace if you break it.

I personally will be doing exactly as I have just described for my RA28 with 18R-GTE with low-moderate boost. Of course for my RA23 with moderate-high boost 3S-GTE, a G series will let me perform hard launches and flat changes without issue!! But that's a lot more expense and weight.

EDIT: if budget isn't a huge problem, then with all the effort you are going to put into the BW diff, an F series has all the advantages of the T series (except width), and none of the weaknesses. They need to be shortened and mounts swapped, have a strong centre and axles, the RT142 brakes fit, LSD - take your pick, Torsen, clutchpack, 1.0, 1.5, 2.0 way etc etc. Far better diff, and around the same money. Plus they are available 4 or 5 stud for your convenience.

[3jcelica]

they have 28 spline axles just like the vl turbo. they have a factory 1.0 way lsd

Are you sure about that, if my memory serves me correct these are not the same Bog Warmer diffs as a VL or a skyline, they have less splines if I rember correctly they are 22 or 24 spline axles and the centre is smaller, similar to a 'T' series in terms of axle size and centre size, The end difference being that LSD are not avaliable as far as I am aware. But I am happy to be disproved because I would like to simple bolt in a 28 spline BW into my corolla.

BTW take a look at the volvo diff conversion thread, strong as an ox, closer to the size you need, disk rear end, and probable a similar weight to an 'F' series, dime a dozen and the price is good (usally very cheap).

Roger

[o_man_ra23]

3J Celica, the ovlov diff has a wierd stud pattern, so that needs to be changed, then brakes to suit, they are reasonably heavy (more than likely heavier than F series), and again you need to modify your tail shaft. Certainly an option, and it has been done, but not a good option IMHO.

[yoshimitsu9]

sorry, i didnt make my self clear enough.

the avante coronas come with a borg warner which has the 28 spline axles, no lsd option to my knowledge. vl turbos come with 28 spline borg warners which have a factory 1 way lsd (i hear they are absolute poo and wouldnt even bother with one) skylines and pintaras also come with the same spline axle borg warner too (i imagine they are all made to different widths however, i beleive the pintara diffs come in 4.1 ratio as well).

[3jcelica]

sorry, i didnt make my self clear enough.

the avante coronas come with a borg warner which has the 28 spline axles, no lsd option to my knowledge. vl turbos come with 28 spline borg warners which have a factory 1 way lsd (i hear they are absolute poo and wouldnt even bother with one) skylines and pintaras also come with the same spline axle borg warner too (i imagine they are all made to different widths however, i beleive the pintara diffs come in 4.1 ratio as well).

Agree with the VL having 28 splines axle and a poo LSD, Agree with the skyline and pintara having 28 spline (better LSD in the skyline GTS), and pintara have the 4.1. However I am yet to see a corona with a (st141,RT142 australian delivery) with a 28 spline. If anyone else can confirm that there is a 28 spline corona avante out there that would be great. All the BW diffs that I have seen out there in coronas are 23 spline (previously I said 22 or 24 but just confirmed 23). But the Avante did range from 84-87 so maybe some of the later ones got the bigger BW diff. Again if anyone can confirm that would be great.

Roger

[o_man_ra23]

Nope, later ones got toyota IRS. From late 85 to 87, they were all IRS. Also the axles I pulled from the last RT142 I saw didn't look all that much better than the T series, so would hardly think they were 28 spline, or worth the effort of installing.

[Norbie]

Corona BW diff is definitely the smaller poo version with no LSD option. They are NOT the same as VL/Skyline BW diffs.