New rear axle or brake conversion??

[Lewie]

Gurus,

I've been doing some research for doing a rear brake conversion from drums to discs on my 83 6cyl VH commodore.

I've rang a few places in the Adelaide area for parts and I've come up with some varying options.

What I want to do is convert from drums to discs because, down the track, I'll be putting in a 308 and I'm re-furbishing/upgrading with that in mind.

Now my question is that because I'm going V8 down the track, would I be better off swapping out the entire rear end for one with discs on it already or just sourcing the parts (calpers, rotors, backing plate, bearings etc) and going at it that way. If I do swap the rear end I'll have to swap the drive shaft, true? and if I do that I'll have to swap the gearbox aswell? At the moment it is completely standard with the trimatic box and 6 cyl everything. Although I'm able to swing spanners to a reasonable standard (enough to keep me out of trouble) I've never done something like this before and I'd love to hear from you gurus about the best way to proceed. I want to do the work myself as this is a learning project for me aswell as a daily driver.

I'm happy to pick up parts from the wreckers/U-Pull-It/Just Commodore Spares as I'm on a budget.

Also, I'm a little confused as to what is compatible with VH's. Are they all exactly the same through to VL?

 

[DANNY8]

Definitely change the whole diff. Your car would have an 8 bolt Salisbury under it, which would break easilly enough trying to handle the 202. Source a borg warner diff out of a VK (more then likely will be drums), and use the VK tailshaft out of the same car (to suit as borg warner diff). You only need to swap the rear half of the tailshaft.

Then source a cheap VN diff and use the disk brakes off of that to put on ur VK borgy diff.

 

[Lewie]

Definitely change the whole diff. Your car would have an 8 bolt Salisbury under it, which would break easilly enough trying to handle the 202. Source a borg warner diff out of a VK (more then likely will be drums), and use the VK tailshaft out of the same car (to suit as borg warner diff). You only need to swap the rear half of the tailshaft.

Then source a cheap VN diff and use the disk brakes off of that to put on ur VK borgy diff.

Do I need to get the diff out of a V8 VK? Will the VN brake setup go straight on? Does the drive shaft pull straight apart (like my old land cruiser shaft) and will it fit onto the back of the standard one or will it need modification?

Thanks for the info to.

 

[DANNY8]

Do I need to get the diff out of a V8 VK? Will the VN brake setup go straight on? Does the drive shaft pull straight apart (like my old land cruiser shaft) and will it fit onto the back of the standard one or will it need modification?

Thanks for the info to.

No the V8's will have a 10 bolt Salisbury (which u may as well get if u can find one, they'd have discs as well). The 6's used an 8 bolt Salisbury and a Borg Warner, you'd have to check out the plates or look under it to know which diff is under it.

I'm not 100% sure if the VN brakes will go straight on, but I presume so, apparantly ya need to use a different oil seal, but I haven't done the conversion yet so not sure.

The tailshaft is a 2 piece, and it pulls apart by removing the allen bolts in the middle, there's 6 i rekon....and normally they're an absolute bitch to crack. Best thing to do is spray them with WD40, tap the heads with a hammer, then use one of those right angled allen keys, put the short end in the bolt, and on the other end use a spanner or some sort of device to put over the end to lengthen it to apply more force. Or sometimes I just do all that but hit the allen key with a hammer to try and crack it!:thumbsup:

If you've got a 6cyl trimatic, well u prolly wont even need to stuff around changing the tailshaft bits, as the car u pull the VK borgy tailshaft out of would probably be a trimatic also, so all you'd have to do is pull ur tailshaft out and fit the vk borgy tailshaft, it will fit no worries......i forgot to mention that earlier....we were using manual boxes so always had to put the front section of our tailshafts onto the borgy rear sections.....but yeah if they're both trimatics ya shouldn't have a problem.

Also, ya could use a VL diff (which is a Borg Warner also), but it's about an inch. It will work but will scrub out depending on how low ur car is and wat size tyres u have. The VK borg warner diff is narrower, which is why it's best to find one of those. A VL diff would be easier to find, but as u need a VK borgy tailshaft, you may as well find a car with it and grab both the diff and tailshaft.

 

[VRSS]

vn brakes will physically bolt on, but you'll need VN oil seals and maybe bearings too, you will find if you bolt them straight on you will have excessive play in the axles, and if you use a shim to space it out it'll leak. so VN bearings and seals should give it the proper clearance.

 

[Lewie]

Thanks for all the info guys. I've got myself a 10 Bolt Salsbury Diff from a V8 VK. Just need to get some replacement bits for the brakes and I'm good to go.

Thanks again.