33 replies to this topic

[tsn007]

asking for a friend vehicle-Torana lx sedan SL Behind a worked 308 and a Celica 5 speed what is the better diff, say in value for money, strength, weight, drivability , occasional skids lol.......etc etc 9inch with tru trac and 31 splines or Banjo with Harrop tru trac 28 splines 9inch for $3000 or Banjo for $2300 thanks

[76lxhatch]

The nine inch will take anything you can throw at it, it is a bit heavier but main drawback is clearance issues with exhaust and sway bar that may require extra work. Will also require driveshaft change and depending on the housing and what the car has already brakes could also need additional work. So its likely to cost a bit more than advertised but once its done you know it won't break.

 

Provided it includes a good axle upgrade, the Banjo would be attractive because there are no surprises with fitment. The housing and caps are still a bit of a weak point but my money would be on the Celica box being a problem long before the diff. If that's really the all-up price (seems cheap?), and there are no plans to upgrade the gearbox I'd be quite tempted by this option.

 

This assumes that either option is a straight bolt-in replacement, as far as it can be. Any differences mean extra work and cost to consider.

[Bigfella237]

As above, if that $3000 for the 9" option is "bolt-in" (already converted) with a Tru Trac centre then that is cheap-as. If it were me I'd definitely be paying the extra $700 just for the peace of mind. (You only need to call a tow truck once and the difference would've paid for itself!)

 

We played all those games with Holden Banjo diffs back in the speedway days and they still weren't anywhere near bulletproof. Even if you beef up the centre and axles they still bust the main caps off and leave a nice impression of crownwheel teeth in the back of the pumpkin!

[Ice]

9 inch 

[LXCHEV]

Yep, for me - 9” for sure. Do it once and never ever have to revisit again.

[RallyRed]

Not sure of your application...but I run Banjo + Detroit Locker. We have 3 ratios , complete housings, ready to bolt in, for different tracks. We run in track events. I have had 4 diffs rebuilt in 4 years. Apprx 300hp 202.
The Detroits are great, just the Banjo C/W and pinions were never design for big power. They just wrar really quickly.
Being a bit of a purist, the 9" thing doesnt sit well, but from what we hear, if you have freedom to use/ no class rules, then they are prob. a good solution.
My 2 cents.

[Heath]

Borg Warner is a more weight-efficient design, and has a more mechnically efficient gearset.

 

Unless you're throwing the book at a 9" it with all the upgrades like ally 3rd member housings, needing weird diff ratios, wanting to weld weird shaped stuff all over the pumpkin or buying some pre-assembled full-floater housing that's easy to buy off the shelf in America, I'd go Borg Warner.

 

BTW 31-Spline is not just for 9"s. My Borg Warner is 31-Spline.

 

They are both "set and forget" for a "worked" 308. I don't really know how hot "worked" is, but both of these diffs have plenty of torque capacity for a strong Holden V8.

[ls2lxhatch]

If you are considering the Borg Warner then have a look at the KAAZ.

 

A KAAZ will give you even torque to both wheels. The TruTrac splits torque roughly 70/30.

[Dr Terry]

BTW 31-Spline is not just for 9"s. My Borg Warner is 31-Spline.

The Holden 10-bolt Large Salisbury has the same 31-spline axles as well.

 

Dr Terry

[Redslur]

The Holden 10-bolt Large Salisbury has the same 31-spline axles as well.

 

Dr Terry

I am pretty sure the large 10 bolt Salisbury is only a 28 spline axle design. Never heard of a 31 spline one.

[Dr Terry]

I am pretty sure the large 10 bolt Salisbury is only a 28 spline axle design. Never heard of a 31 spline one.

You are correct, I was thinking of the M80 late models with the 30-spline axles.

 

Dr Terry

[ozyozyozy]

Will depend on your end game really.
Will you build more hp, will you be doing more than cruising.
If your going to go bigger later, beat up on the car alot then 9 inch otherwise BW with a KAAZ is a pretty good option/allrounder

[tsn007]

has anyone had a Banjo diff with a trutrac conversion blow up

[RallyRed]

No. Had a banjo with Trutrack. I guess you already know that the T/T is just the centre. You are stil using your factory crown wheel & pinion. Thwy seem to be the sacrificial bits in my experience. Regardless of T/T or Detroit locker centre, high HP / competition type use just wears them out.

[claysummers]

Axles as well. I suppose the fine splines may solve that, but yes the gearset. Same deal with the UC VB-VK Salisbury's.

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[yel327]

Not VK Clay, and add WB.

[claysummers]

Thanks Byron. Didn’t know about WB, why they didn’t use the big Salisbury I wonder. Not that they are that much stronger. The VK were all BW then?


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[Statler]

I went with the Ford truck diff.

Besides an almost never ending choice of ratios , & parts availability , it was an opportunity to upgrade to a thicker wall tailshaft & a larger Uni. 

[yel327]

Thanks Byron. Didn’t know about WB, why they didn’t use the big Salisbury I wonder. Not that they are that much stronger. The VK were all BW then?

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WB did use large Salisbury behind V8. VK 6cyl were Borg Warner, V8 was large Salisbury.
You’d think a large Salisbury would have to be rated for at least 150% torque of a banjo or disguised banjo.

Edited by yel327, 04 June 2023 - 07:51 AM.

[76lxhatch]

VKs here came with small and large Salisbury, only the EFI sixes were Borg Warner

[Bruiser]

Copied and pasted from a commodore forum:

Up until Feb/March 85, all commodores had salisbury diffs
These were available in 2 sizes - the 178mm ring gear version (the small sals - identified by a round cover plate) and the 190mm ring gear version (the large sals) identified by an egg-shaped cover plate.

Tha large sals was only available with the 5L
the small sals was put in all others, 4 cylinder, all 6 cylinders, and the 4.2L - the 4.2L had a larger yoke than the 4/6 versions.
Apart from the first 200 VB 4.2L diffs, all 4.2L diffs have disk brakes.
The only way to get discs on a 6 cylinder diff was in an SL/E or Calais - but the VK Calais 6s were all EFI, and the EFI ran a 4.2L size yoke...
Apart from that, it was a costly option available only on the mid-range models.

Confused yet?

Now, the small sals had the following ratios (extremely rare LSD optional):
2.78:1 (generally fitted to SL/E 6 & 4.2)
3.08:1 (generally fitted to VB/C SL & VH SL/X 6 & 4.2)
3.36:1 (generally behind base model 6s, and most 2.85s)
3.55:1 (much rarer, only optionally available)
3.9:1 4 cylinder only - torana stud pattern.

The big sals (both with optional LSD - relatively available):
2.60:1 (VH SL/E 5L only)
3.08:1 (most other 5L)
I have never seen one, but some people reckon a 3.55:1 large sals was made, but I have absolutely no part numbers in any listings for one.


Seems borgwarners appeared during the run of VKs

[yel327]

Yes, that is right I think, early VK still had the small Salisbury, change to BW mid Series. The ratios on small Salisbury used were no different to how they were with banjos, as in you shouldn't find 3.36 or 3.55 or 3.90 behind V8 (4.2L) in VB-VH, only 2.78 and 3.08 - same as banjo was in HK-LX. However, you will find 3.08 and 2.78 behind some 6cyl (not 2.78 in HK-HG).

[rexy]

has anyone had a Banjo diff with a trutrac conversion blow up

 

No, but I have broken gearsets (3.08 and 3.36) using a 175KW at the wheels 308 manual.

 

I wish I had spent money earlier on the nine inch than the money I wasted on tow trucks!

[Uncle Chop Chop]

VK series II went to BW diff. Not sure of the production date, though.

[claysummers]

I had an injected VK Berlina. Diff plug was rubber. Methinks BW?


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