Tyres rubbing with narrower VL diff

[greenfoam]

What he said ^^^^

Even for the LSD you should have just taken the housing out and swapped that over as all the VL LSD diffs were 4 pinion, 28 spline diffs just like the VL.

Im presuming its a VL Turbo diff to be 3.45 LSD, as the NA diffs were not LSD and the V8 LSD diffs were 3.08 ratio's.

The VN Group A and SV5000 used the VL Turbo diff to fit the wider rims under the guards, however they werent sitting on ultralows.

I blame the problem on your ultralows, either get superlows or put a VN diff back in your car.

The Group A ran mini tubs in the rear wheel arches to get away with it, also as mentioned earlier VP/Q IRS wheels might make it fit or swapping the center into the VN housing, I'd be cutting the wheel arches and welding in mini tubs and using it as a good excuse to fit 265s in there on 16x8 inch rims so it's all kinda legal !

 

[greenfoam]

The centres could be the same but in the wagon housing yeah, but it would need the VL Turbo/V8 axles also.

Hmm and generally, knowing Holden, they would have just put a complete diff in without changing bits around. Look at VB to VP with suspension, VN to VZ with chassis etc.. Carry over parts up until the VE were a shocking habit of Holdens (Same with Ford...such as the Territory being modified off the AU wagon).

The XM/P Falcons are just a different shell on a Mustang. And the Valiant Charger is the Valiant Ute with a sex body on top

 

[Cheap6]

Front Tr Rear Tr
VL Sed 1451 1433
VL wag 1451 ?
SV5000 1477 1468
VN Sed 1451 1478
VN GPA 1519 1502


VN GPA-VL Sed 68 69

SV5000-VL Sed 26 35

(mm)

This is from old Excel file I have where I was looking at various combinations of VL, VN, VP rear axle and wheel offsets. Assuming no changes in front end track width over VL/VN due to hardware, it would appear that the VN GPA does use the VL sedan axle housing with wheels with 34 mm (= 68/2) less positive offset than standard VN/VL wheels.

The nominal diameters of the two wheel tyre combos are for VN GPA and standard 15" are:

225/50/16 631.4mm
205/65/15 647.5mm

so no prob. with diameter.

Edited bit: [Thinking about it, I think that the track widths for the VN GPA may be wrong. There is no way that would fit within standard guards. They were pulled from a contemporary magazine road test spec. list so may be the result of an error in transcription (the magazine's, not mine ). They would make more sense if the total increase in track width over the standard 43P rims due to the wheel offset was 34mm, as per VP/VQ IRS. I'll see if I can find some more data when I have access to it. The increase in inside clearance would be 17mm (extra rim offset)-10mm (1/2 increased tyre width)=7mm for a 225/50/16 over the 205/65/15 combo on a standard width VL rear axle with 43P wheels.]

The VN SV5000 would appear to have a wider rear axle than the VN GPA but narrower than other VN's. I can't find VL wagon track spec's yet but if they are 1442mm (=1468-26) or so, that would indicate that was what was used in SV5000.

 

[Cheap6]

The centres could be the same but in the wagon housing yeah, but it would need the VL Turbo/V8 axles also.

So VL V8 wagon axles? I doubt the jig used when welding on the mounting brackets would need to be changed much if at all between wagon and sedan.

 

[Cheap6]

Weight; Track Front; Track Rear; Wheelbase; Source of spec.; Tyre size; Tyre Nominal Dia.;

VN GPA; 1557; 1519; 1502; 2731; Motor Oct '90; 235/45/17; 643.3;
VN GPA; 1477; 1466; -; Car Aust. Apr '91; 235/45/17; 643.3;
VN GPA; 1477; 1468; -; Wheels Sep '90; 235/45/17; 643.3;
VN SV5000; 1436; 1477; 1468; 2731; Wheels Jun '90; 225/50/16; 631.4;
VN SV5000; -; 1477; 1468; -; Wheels Jan '90; 225/50/16; 631.4;

Please forgive the formatting. I dug around and the data suggests that both VN GPA and SV5000 have the same front and rear tracks: F=1477 and R=1468. Assuming that the front suspension is unchanged, 1477-1451=26mm. For the rear: 1468-26mm=1442. I reckon that's a wagon diff. .

I also found prices quoted for VL turbo wagons, SL and Berlina. That was news to me too.

(I did find VK wagon rear track: 1440mm but that is a different type of diff.)

 

[defa]

series 2 vk's would be the same as vl's diff's wouldn't they. so i was told. a mate of mine had a series two vk and it had a borgwarner diff in it..

 

[1991_Vn2nV]

series 2 vk's would be the same as vl's diff's wouldn't they. so i was told. a mate of mine had a series two vk and it had a borgwarner diff in it..

Yes but smaller.

 

[bradj]

BW78's are all the same.
How can they be smaller?
There are a couple of good technical threads on diffs on here from genuinely qualified people, look them up or call Diffs R Us for the right answers.

 

[_R_J_K_]

This thread is almost three years old.

 

[Immortality]

BW78's are all the same.
How can they be smaller?
There are a couple of good technical threads on diffs on here from genuinely qualified people, look them up or call Diffs R Us for the right answers.

nice thread dig :bang: and there are differnces in width between VK/VL and VN diffs :thumbsup: