TR6 Wishbones

[T Robinson]

Hi All,

 

Does anyone out there know if TR6 lower wishbones will fit a TR3 as I wish to fit TR6 Urights and trunnions?

 

Thanks,

 

Tony

[Bob Smith]

Hi All,

 

Does anyone out there know if TR6 lower wishbones will fit a TR3 as I wish to fit TR6 Urights and trunnions?

 

Thanks,

 

Tony

 

Tony, Yes it is possible to do as you suggest but you need to fit later upper wishbones and the later top ball joint as well. Remember to retain your old shock absorbers springs and rebound rubbers - the later shock absorbers will not be suitable as they will damage the chassis.

[T Robinson]

Thanks Bobby,

 

Appreciate your reply,

Tony

[jean]

Another suggestion .I modified my TR3A suspension by retaining the original lower wishbones and uprights. I did fit 3 deg trunnions, TR6 upper wishbones and balljoints. For a 1,5deg camber I fitted the Revington upper mod. kit. All works to my great satisfaction. If you fit more TR6 parts you will probably also have to modify or replace the steering arms and brackets, do not know in how far they match with the TR3 steering components, but the TR6 steering arm's eyes will probably not fit

 

HAPPY NEW YEAR to ALL

[john minchin]

Tony,

 

In my experience as I have tried this on my TR4 you have to fit the lower wishbones and vertical link as a set. The TR6 wishbones leave a gap too small for the TR2/3/4 trunion and the bushing is different at the trunion end although the inner (chassis end) is the same for both top and bottom.

 

But this biggest problem is the different ride height given by the TR6 trunion and vertical link. The hole for the wishbone and axle pins are at very different heights between the TR2/3/4 and TR4a/5/6 uprights. My TR4 with TR6 front suspension (top and bottom wishbones, shock absorber, spring pan, trunions, uprights and ball joint) gave a ride height which meant the chassis was very low to the ground.

 

I changed the spring pan back to the TR4 original as this was different with no real improvement.

The shock absorber, although on a TR6 provides bump stop control on a TR6 does not work on a TR2/3/4/ chassis as the wishbone hits the chassis (as mentioned previously). So I now have TR6 shock absorbers, TR4 lower bump stop, TR4 spring pan, TR6 trunions and upright, standard TR4 spring 210903 and rubber collars PLUS a 22mm spacer made out of a spacer 107682 (from a kind forum user) used for the shorter spring TR4 set up and hacksawed off and then releived on the inside with a series of drill holes to provide the seating into the top of the suspension turret.

 

The 22 mm spacer thickness was derived after many trials with no spacer, full 107682 spacer and bits of MDF then plotted on a graph and cut as I had one chance to cut the spacers and now it rides a fraction lower than my TR3a but looks OK. The TR6 engine in my car apparently wieghs no more than a TR4 engine as the TR6 front spring rates are the same.

 

So in my experience yes it can work and the above should short-cut you to the desired set up. No one else has mentioned the trunion and vertical link difference which intriges me as the difference between trunion pin (the wishbone link) to axle pin centres is 68mm on a TR2/3/4 and 101mm on a TR4a/5/6 according to my measurements and this must make a difference !

 

Any questions please ask.

[T Robinson]

Tony,

 

In my experience as I have tried this on my TR4 you have to fit the lower wishbones and vertical link as a set. The TR6 wishbones leave a gap too small for the TR2/3/4 trunion and the bushing is different at the trunion end although the inner (chassis end) is the same for both top and bottom.

 

But this biggest problem is the different ride height given by the TR6 trunion and vertical link. The hole for the wishbone and axle pins are at very different heights between the TR2/3/4 and TR4a/5/6 uprights. My TR4 with TR6 front suspension (top and bottom wishbones, shock absorber, spring pan, trunions, uprights and ball joint) gave a ride height which meant the chassis was very low to the ground.

 

I changed the spring pan back to the TR4 original as this was different with no real improvement.

The shock absorber, although on a TR6 provides bump stop control on a TR6 does not work on a TR2/3/4/ chassis as the wishbone hits the chassis (as mentioned previously). So I now have TR6 shock absorbers, TR4 lower bump stop, TR4 spring pan, TR6 trunions and upright, standard TR4 spring 210903 and rubber collars PLUS a 22mm spacer made out of a spacer 107682 (from a kind forum user) used for the shorter spring TR4 set up and hacksawed off and then releived on the inside with a series of drill holes to provide the seating into the top of the suspension turret.

 

The 22 mm spacer thickness was derived after many trials with no spacer, full 107682 spacer and bits of MDF then plotted on a graph and cut as I had one chance to cut the spacers and now it rides a fraction lower than my TR3a but looks OK. The TR6 engine in my car apparently wieghs no more than a TR4 engine as the TR6 front spring rates are the same.

 

So in my experience yes it can work and the above should short-cut you to the desired set up. No one else has mentioned the trunion and vertical link difference which intriges me as the difference between trunion pin (the wishbone link) to axle pin centres is 68mm on a TR2/3/4 and 101mm on a TR4a/5/6 according to my measurements and this must make a difference !

 

Any questions please ask.

 

 

Thanks John,

 

Here's how I will tackle it now............

 

I will use existing lower wishbones, spring pan etc.

I will use the TR6 (TR4A) uprights with 3deg offset along with TR6 upper wishbones, shortened by 6mm to give aprox 1 deg negative camber.

The bottom trunnions will be the early 4A ones that will suit the existing wishbone assembly.

 

Here's hoping..........

 

Regards,

 

Tony