Jump to content


Photo

Fitting a Nine-Inch


  • Please log in to reply
31 replies to this topic

#1 enderwigginau

enderwigginau

    Admin Wrangler

  • Moderators
  • PipPipPipPipPipPipPip
  • 2,000,527 posts
  • Name:Grant
  • Location:Brisneyland
  • Car:76 LX Sedan, 4 seater
  • Joined: 04-February 07

Posted 30 September 2008 - 09:16 PM

Hi All,
After some info on issues you have had/seen/heard of when fitting a nine-inch, even if not to a Torana. Things to get right, and what happens when you don't!!
Or what to use to get something right.

Things like:
Control Arm mounting location
Pinion Angle
Pinion's hit floors
Adapting stock brakes
Adapting aftermarket brakes
Wheel PCD's
Tailshaft and exhaust clearance
Housing straightness
Widths
Available axles
Wheel bearings

All responses appreciated.
It will definitely be a big help to everyone in the future.

Grant..

#2 enderwigginau

enderwigginau

    Admin Wrangler

  • Moderators
  • PipPipPipPipPipPipPip
  • 2,000,527 posts
  • Name:Grant
  • Location:Brisneyland
  • Car:76 LX Sedan, 4 seater
  • Joined: 04-February 07

Posted 01 October 2008 - 12:56 PM

Bump

#3 bullitA9X

bullitA9X

    Oh My, Don't you post alot

  • Members
  • PipPipPipPipPipPipPip
  • 4,129 posts
  • Location:south australia
  • Joined: 08-November 05
Garage View Garage

Posted 01 October 2008 - 03:14 PM

Hi in relation to exhaust and 9inch on lc-lj the biggest problem i have come across is anything bigger than 2 inch gives major headaches to clearance as with the 9inch there is not much room i have a 9inch with custom twin 2 1/2 inch pipes on my lj and it bangs on the top control arm and you can not stop it but with the 2inch no problem so there is one for ya :spoton:

#4 _waz355_

_waz355_
  • Guests

Posted 01 October 2008 - 03:31 PM

Some of you have probably read in another thread I have had problems with a 9 inch in an LX with the diff housing sitting to one side, which I haven't had a chance to get to the bottom of it yet. This weekend the wife is allowing me to work on my car so will let you know what I find.

This is the 3rd nine inch conversion I have done the other 2 were on a HG and a HK. I have always had a play down the strip with my cars and pinion angle is something I always adjust. All the conversions I have had did not have the correct pinion angle to get the traction required to get off the mark. So adjustable top arms are great for that, which is what I have always run.

Obviously exhaust clearance is a problem with 9 inch's in torana's mine goes under the diff as I would imagine everyones would??? This is a real hassle with putting the car on a 2 post hoist as the suspension hangs on the exhaust system.

I had a set of billet axles made with the diff housing the whole lot cost me $1500 without the centre for those wondering about cost. If you want I can give you his details - in Brisbane.

I run the standard rear drum brakes, but will go to bigger brakes later. The axles I had made have both the torana and the HQ stud pattern you just have to move the wheel studs to change stud pattern so changing to HQ brake is not a big deal.

I know adapting the standard sway bar can be an issue sometimes, but mine just fits.

Haven't had too many other problems will keep you posted on my current one anyway.

Edited by waz355, 01 October 2008 - 03:33 PM.


#5 _lx-304_

_lx-304_
  • Guests

Posted 01 October 2008 - 07:14 PM

when fitting vn- discs to replace drums,i had axle play in and out of the diff.i was told this is because there is a seal for drums and a seal for discs.



dave

#6 Bomber Watson

Bomber Watson

    Not nearly as smart as Lazarus

  • Members
  • PipPipPipPipPipPipPip
  • 20,583 posts
  • Name:DJ
  • Location:Rockhampton, the exact center of my own TINY universe. Also the home of the worlds longest location.
  • Car:Mixed fleet of Taxi's and hair dresser mobiles.
  • Joined: 07-November 05

Posted 01 October 2008 - 07:38 PM

The shank on the axel is a different lengh. Its not a strait swap.

Be carefull how much narrower than standard you go if your fitting the disks, i had to get custom smaller springs made up and cant fit hand brake cables.....

Cheers.

#7 _kolman_

_kolman_
  • Guests

Posted 09 October 2008 - 12:46 PM

I have a 9inch in my LX hatch with billet axles, disk brakes and exhaust going over the diff.

Control Arm mounting location
who ever you get to do the conversion should get this right or there will be problems

Pinion Angle
not an issue, i guess this would be set by the above

Adapting aftermarket brakes
If fitting commodore disk brakes a bit of modification is required but nothing to difficult for the average home mechanic. From memory you need to swap brakes from left to right side to avoide the shocks. if preferred you can modify the backing plates with a bit of cutting, bending redrilling to suit. If you want a handbrake you will need to swap the left and right handbrake mechanisims over so they are activated by a cable pulling the lever. I found that I was unable to get the cable and lever 100% perpendicular so not as effective as it could be but it still works.

Wheel PCD's
Depends what you want, you can use the ford axles you might get with a 9" but then you will need ford rims. Some rims have multi stud patterns (ford 5x4.5 / chev 4x4.75 ) such as convo pros so this can work if you have chev pattern front and ford pattern rear. Get holden axles resplined / modifyed so you have holden PCD. Get billet axles made to suit diff with what ever PCD you want.

Tailshaft and exhaust clearance
Should not have an issue with the tail shaft, I run a 3" shaft with no clearance issues. Exhaust is an issue with no easy solution, there is not to many installations that I have seen that have been done the same. You can go over but there is not much room with a 9" and you are limited to what size exhaust you can use. I run a 3" system to the mufflers, then have a flange so I have a couple of options.(1) I can run 2 1/4" inch over the diff which is good for the street but is quite restrictive and you can notice the power loss. (2) bolt on 3" tail pipes that go under the diff which causes ground clearance problems and is a pain when jacking up cause exhaust his diff. (3) chuck on some dumpers, not police friendly

If you want to attemp the conversion yourself you will obviously need to know a bit more. The best thing to do is work out want you want and how much its gonna cost. Also triple check any measurments cause if you get it wrong it will end up costing double.

rough estimate of what i paid.

complete 9inch minus centre to suit torana with HQ axles and drum brakes. $700
Sold axles and brakes for $200
Shorten the housing couple of inches and determine axle measurments. $500
Billet axles. $500
commodore brakes second hand complete. $70
New rotors. $110
Hand brake cable modified. $200 I think??
Centre $1000

Just under 3K all up.

Hope this helps.

cheers,

#8 _moot_

_moot_
  • Guests

Posted 09 October 2008 - 01:21 PM

axles: be careful in how much you can shorten your diff to suit. factory 9" axles taper,and you cant cut a spline into a taper. i had to get billet axles (which dont taper) to get the axles short enough.though my car is tubbed with no flares.

brakes: i used vn discs on mine and i have moved the lower control arm mounts in 15mm. i had to mount the caliper on the top (in the 12 o'clock position) of the brake disc,where the factory spring used to be.i have 10mm between the lower control arm and the disc with no backing plate.and therefore no internal drum for a hand brake.
i have nissan pintara rear calipers and brackets,it bolts straight on and the calipers have a mechanical handbrake built into them that are attached via torana hand brake cables.as pintaras an commodores use borg waner diffs some brake bits interchange

bottom bit in bold text worked out really well.

also vn and hq stud patterns are very close,by the time i drilled the vn discs to suit 1/2" wheel studs they'll fit nicely on hq pattern axles

Edited by moot, 09 October 2008 - 01:28 PM.


#9 ass308

ass308

    SSTORY

  • Members
  • PipPipPipPipPip
  • 1,058 posts
  • Location:NEWCASTLE
  • Car:3/76 SS hatchback
  • Joined: 16-August 08

Posted 09 October 2008 - 01:42 PM

why go over the diff with your exhaust when u can go under.i had a 2 and a quater inch duel system that went under my nine inch.i was skeptical about it at 1st,but exhaust guy told me, he would redo it if it hit.it didnt and was no problem at all.
acording to my nine inch builder,the best way to get your nine inch shortened is to give the builder your car, nine inch ,and wheels.he puts wheels under guards where u want em and makes it suit.
in sydney if u want to run a nine inch with ten inch rims see http://www.consulmotive.com.au/ before u do anything

Edited by ass308, 09 October 2008 - 01:44 PM.


#10 _moot_

_moot_
  • Guests

Posted 09 October 2008 - 01:44 PM

Posted Image

#11 _cruiza_

_cruiza_
  • Guests

Posted 12 April 2009 - 08:21 AM

I ran a 9 in with HQ front Disc's and standard Ford calipers cost was $1500 to get it made up, I suppied them with a complete diff out of a XB GT coup clutches were shot so had to spend more on reconditioning the center as well, then then there was the custom tailshaft but I had off the shelf bearings, common cheap, same with brake pads drive shaft Crosses etc , 120,000 km later of hard use I was replacing those parts so glad I had the setup I had, and I had a custom 3inch mandel bent exhast going over the diff no problems, no knocking with car fully loaded or empty, took exhast guy 8 hours working on my car to do, I was there watching him do it.

So yes it can be done but it was expensive

#12 bathurst-racer

bathurst-racer

    Forum Fan

  • Members
  • PipPipPipPip
  • 342 posts
  • Location:Central West NSW
  • Car:1972 LJ XU-1
  • Joined: 13-August 08
Garage View Garage

Posted 12 April 2009 - 09:01 AM

I'm curious as to why you would run a 9" in a road going Torana. As it has been mentioned there are clearance problems and great expense involved in this conversion. Surely the weight issue and drain on horsepower would concern anyone who covers a big mileage due to increased fuel consumption and ill effects on handling.
We found that most cars are much better off using the Borg Warner LSD as found in later XE/XF Falcons and Fairlanes. Its a smaller diff, much lighter with many ratios available and able to cope with the torque of most cars running down the strip. I know the 9" is very popular and almost everyone will jump up and down at my suggestion but I hope to learn something by asking the question.

Edited by bathurst-racer, 12 April 2009 - 09:03 AM.


#13 wot179

wot179

    Green Eggs and Spam

  • Members
  • PipPipPipPipPipPipPip
  • 6,766 posts
  • Name:Jesus Bloody Christ
  • Location:Sunny Santa Maria
  • Car:Goon
  • Joined: 06-February 09

Posted 12 April 2009 - 09:21 AM

I'm curious as to why you would run a 9" in a road going Torana. As it has been mentioned there are clearance problems and great expense involved in this conversion. Surely the weight issue and drain on horsepower would concern anyone who covers a big mileage due to increased fuel consumption and ill effects on handling.
We found that most cars are much better off using the Borg Warner LSD as found in later XE/XF Falcons and Fairlanes. Its a smaller diff, much lighter with many ratios available and able to cope with the torque of most cars running down the strip. I know the 9" is very popular and almost everyone will jump up and down at my suggestion but I hope to learn something by asking the question.



Excellent point.

To my mind,if the conversion is done for strength,it is a pointless excercise using resplined axles.Many other lighter conversions will do the same job if you are using resplines.

If the conversion is done for ease of ratio change,then I guess thats fair enough.But how often do you swap centres?

If aftermarket axles centres and/or brakes are to be used,(Mark Williams,Strange etc) why not stick a Chev 10 or 12 bolt in it?All the aftermarket stuff is strong as,and at least it will all still be GM.
Im not saying 9inches are crap,but they are far from bulletproof.If you are doing a conversion,keep the faith,keep it GM.

#14 Statler

Statler

    Heckler Extraordinaire

  • Moderators
  • PipPipPipPipPipPipPip
  • 6,036 posts
  • Name:Col
  • Location:Mackay Qld. Whitsundays for all you back packers!
  • Joined: 20-May 06

Posted 12 April 2009 - 09:36 AM

Control arms:

I have noticed when fitting the 9" into LH/X, that the top p/s control arm may need a small amount of metal ground off to allow the control arm to pivot.

This has been the case with both my diffs.

#15 ls2lxhatch

ls2lxhatch

  • Members
  • PipPipPipPipPipPipPip
  • 5,293 posts
  • Location:Perth
  • Car:LX Hatch
  • Joined: 29-May 06

Posted 12 April 2009 - 12:15 PM

The BW M78 is a good value for money diff conversion but it has its limitations.

The LSD is the weakest point in a BW M78. If you have 300 HP+ then the BW LSD will not last long, you would have to look at replacing it with either a KAAZ, Lokka or spool.

The next weak point is where the axle tubes are plug welded into the cast iron centre. If you have 500 HP+ and run slicks on the weekend then this may be an issue.

#16 _cruiza_

_cruiza_
  • Guests

Posted 12 April 2009 - 03:23 PM

I'm curious as to why you would run a 9" in a road going Torana. As it has been mentioned there are clearance problems and great expense involved in this conversion. Surely the weight issue and drain on horsepower would concern anyone who covers a big mileage due to increased fuel consumption and ill effects on handling.
We found that most cars are much better off using the Borg Warner LSD as found in later XE/XF Falcons and Fairlanes. Its a smaller diff, much lighter with many ratios available and able to cope with the torque of most cars running down the strip. I know the 9" is very popular and almost everyone will jump up and down at my suggestion but I hope to learn something by asking the question.


I can not really answer that question for everyone, obviously, but in my case I had the option of Borg warner or 9 inch both were disc braked and out of Falcon coupes, knowing the 9 in had the ratio i wanted and was Limited slip and lets face going 9 inch is not normally going to be a mistake. It never gave me any trouble the limited slip was perfect for the car once setup correctly and the brake balance was spot on too. Also at the time it gave me the option of later on going to a big horse power motor although in the end I found nearly 400hp to be enough for general street duties, AS for fuel economy I used to get better then 20MPG, which was way better then any of my mates could do with standard Banjo diffs and less power. Mind you they did not spend the money I did on reseach and building the thing.

I think though if the cost of converting a 9inch or any other diff are simalar then most would opt for the 9 inch

#17 bathurst-racer

bathurst-racer

    Forum Fan

  • Members
  • PipPipPipPip
  • 342 posts
  • Location:Central West NSW
  • Car:1972 LJ XU-1
  • Joined: 13-August 08
Garage View Garage

Posted 13 April 2009 - 10:30 AM

Hi ls2lxhatch

You're right in pointing out that the BW diff isn't for everyone. I only wonder why people would run one in a Torana size road car which may see some strip action. A well built BW can handle up to 300hp on street tyres and most of us fit into that category. With 500 hp and slicks, particuarly in a heavy car then the next 9" problem arises, that of the pinion winding up on the crownwheel and pushing the bolts out of the housing where the front pinion bearing carrier mounts up.
Then its time for a Dana.
What actually made me curious about all of this was a LJ, stove hot six, Aussie 4 speed and 9". The rear end groaned everytime we had it on the hoist. If that car had a decent V8 and a proper rear suspension set up fair enough but as a street car and potentially a 14 sec time card to its credit the 9" was a very poor choice of components.

#18 _studricho_

_studricho_
  • Guests

Posted 28 April 2009 - 08:35 AM

After blowing many standard diff in my UC I was recommended to run a 9". Bear in mind that I ran a hot red 6 at the time.

Over kill? Yes, but I was sick of changing diffs. Also they add up after a while too.

Extra weight? Yes, I noticed that the car behaved different with the extra weight, but no more blow diffs.

The guy that did my conversion was rough. It was about 14 years ago, but I have had all the faults fixed and it's working well for me with the RB25DET power plant. It also gives me piece of mind that it won't break as I squeeze more power in the future.

Having said that. If I had my time again i won't go 9" again. Many people are using different diffs that are strong enough to handle the power like said before.

I'm running a 3" exhaust over the diff. It's tight, but works okay. I have no issues with tail shaft or pinion hitting.

I guess that's due to the different floor plan in the UC.

#19 arrimar

arrimar

    Lotsa Posts!

  • Members
  • PipPipPipPipPipPip
  • 3,001 posts
  • Location:brisbane
  • Car:Salamanca L34, Absinth LH SLR/5000, Caribean Blue LH 5.0
  • Joined: 13-January 06

Posted 28 April 2009 - 06:01 PM

Put a drain plug in the bottom and make sure the bush in the top control arm mount is either removable or in good nick before welding the mount on. (the mount that sits closest to the centre)

#20 tefa

tefa

    Forum Member

  • Members
  • PipPipPip
  • 191 posts
  • Name:Teflon
  • Location:Belgrave South
  • Car:LX 4 Door SL
  • Joined: 12-February 09

Posted 01 March 2010 - 04:33 PM

Anyone fitted a Mcdonald Bros Rear Chasis clip??file:///C:/DOCUME%7E1/Tefa/LOCALS%7E1/Temp/moz-screenshot-5.jpg

#21 brendan_h

brendan_h

    Forum Fan

  • Members
  • PipPipPipPip
  • 320 posts
  • Name:Brendan
  • Location:sydney
  • Car:lj torana
  • Joined: 26-October 09

Posted 02 March 2010 - 08:31 PM

im curenty getting a 9inch made for lj

as for exhast is there any legal issues with going under the diff?

what about dumping it before the diff? i have herd its exhasut must finish some many MM after the last opening window

this is for NSW

Edited by brendan_h, 02 March 2010 - 08:31 PM.


#22 Statler

Statler

    Heckler Extraordinaire

  • Moderators
  • PipPipPipPipPipPipPip
  • 6,036 posts
  • Name:Col
  • Location:Mackay Qld. Whitsundays for all you back packers!
  • Joined: 20-May 06

Posted 02 March 2010 - 09:25 PM

i have herd its exhasut must finish some many MM after the last opening window


I can't wait for the english translation! LOL

#23 brendan_h

brendan_h

    Forum Fan

  • Members
  • PipPipPipPip
  • 320 posts
  • Name:Brendan
  • Location:sydney
  • Car:lj torana
  • Joined: 26-October 09

Posted 03 March 2010 - 02:03 PM

i have herd its exhasut must finish some many MM after the last opening window


I can't wait for the english translation! LOL



i realy need to re read what i write.

i have herd the exhaust must finish so many MM after the last opening window

#24 mello92

mello92

    Everything Torana, and much much more

  • Members
  • PipPipPipPipPip
  • 1,930 posts
  • Name:Carmelo
  • Location:Townsville 4818
  • Car:LX Sedan
  • Joined: 22-March 09

Posted 03 March 2010 - 02:06 PM

Brendan - Ive got a cousin in NSW who has dumped the exhaust on his ute. He told me that its 600mm after the last opening, whether it be a window or door.

#25 brendan_h

brendan_h

    Forum Fan

  • Members
  • PipPipPipPip
  • 320 posts
  • Name:Brendan
  • Location:sydney
  • Car:lj torana
  • Joined: 26-October 09

Posted 03 March 2010 - 05:45 PM

thanks for that, basicly the exhaust will need to go over the diff then in a lj torana 4 door




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users