BTR for GKN

[Ozstyle]

Hi,
can anyone tell me if changing the the GKN diff for a BTR unit is as simple as obtaining the front and rear BTR diff chassis mounting brackets and bolting in. Will it bolt in, will the prop and drive shafts bolt up without modifcation etc? My GKN diff is shot so needs replacing and since I'm in Australia it may be the cheaper and simpler option. Appreciate any advice from anyone who has attempted or has knowledge of this.

thanks.

[lig]

Hi Fella,

I am sure that will be the case but give TVR Power a quick call on 02476 366177 (UK number), I am sure they will confirm.

Lig.

[IPAddis]

I asked about this when my GKN diff went and I was told it would be expensive with welding of new mounting points to the chassis and so on.

I'd be interested if you hear otherwise.

Ian A.

[v8sag]

Hi Ozstyle
The Holden BTR diff is a different housing to a TVR,although same internals,so either way you would have to change the mounts.
I wouldn't think it would a major to have the GKN refurbished in Aus.

[Ozstyle]

Thanks for the replies,
I had a feeling it was not that simple. My pinion has lost a few gear teeth so it's not a simple overhaul. I need to get a pinion and crown wheel set (new or used). I have contacted CTS to see if they can help out. If I can't source these then I think I will have to get a secondhand diff shipped over from a specialst breakers in the UK.

[IPAddis]

Try Bernie at Competition Transmission Services (I think). They were the only people in the UK who could supply parts for my GKN diff.

Ian A.

[Ozstyle]

Well now I am confused. After contacting Bernie at CTS he tells me the swap is straight forward and simple (after speaking to a customer who has done it). Just get the BTR mounting brackets from TVR and in it goes, with a bit of fettling for the speedo wheel. He can't help with the GKN crown and pinion set.

So some conflicting info - if it was that easy I thought it would be a common upgrade and there would be some threads on here. I don't want to go down the wrong path with this.

Any experts out there know the specific details on the BTR diff and which Australian donar car it comes off?? I figure its of the V8 Holden Commodore from the late 90's. May have to go crawling around some breakers!

thanks-Ozstyle

[mongoose]

What you could do with are some pictures and measurements from underneath the car,of the mouting bracket etc,to at least enable you to make a comparison.I'll be underneath mine next Tuesday,and could mail you some pics of the BTR set up if you like?

[Ozstyle]

I would appreciate that Mongoose.
My concern is the drive shaft lengths, bolt hole patterns on the drive shaft and prop shaft connections. If the BTR Australian diff casing is different as suggested, then that may throw up more problems. Shipping a secondhand GKN unit from the UK may be a simpler option although not the cheapest or the most desirable.

thanks, Ozstyle

[mongoose]

Ozstyle said:

I would appreciate that Mongoose. My concern is the drive shaft lengths, bolt hole patterns on the drive shaft and prop shaft connections. If the BTR Australian diff casing is different as suggested, then that may throw up more problems. Shipping a secondhand GKN unit from the UK may be a simpler option although not the cheapest or the most desirable. thanks, Ozstyle

No problem.Drop me an e-mail through my profile,so that i have your mail address,and i'll send you the pics on Tuesday evening

[v8sag]

Hi Ozstyle
Drop me your email,I have a bare chassis here and some diff's and can throw you some pics.
I would also invesigate the crown from the XJS as they ran GKN and similar ratio.I'll measure the commodore diff to for comparrison,handy having both cars

>> Edited by v8sag on Wednesday 3rd May 11:36

[Ozstyle]

Thanks V8sag,
I have emailed you. I see the XJS ran a GKN diff, but no idea if any parts are interchangable. Think a 2.88:1 ratio would not suit a Griffith.

thanks,

Ozstyle

[v8sag]

Hi Mark
Sent you pics yesterday,but their bouncing back.
Some off the Jag GKN diffs I were looking at were 3.54,might be worth investigating?