Suspenders

[Lebro]

Now I've got your attention !

 

Been reading the various posts about improving the front suspension on early TR's, & got to thinking that it would probably be a good idea to improve my '3.

 

I want to stick with the original steering box as I don't find it too heavy, and it is a good one with not much play.

I have steel 4½" rims with 165R80 radial tyres.

I'm thinking alter camber angle to 0° to improve the look of the car, & to improve cornering ability.

Alter castor angle to whatever the later cars are 3° is it? to improve the self centering of steering.

Fit the Revington sprung peg to the steering box, & the replacement peg & bushes for the centre tie rod to further reduce steering slop.

Possibly fit the "reduce bump steer" kit (longer outer tie rods, & special steering arms) from Revington.

 

I don't particularly want to adjust the camber angle, just make it 0°

 

So question is do I just get all from Revington (quite expensive), or would I be better off using standard (later car) parts where appropriate.

Edited January 30, 2016 by Lebro

[marki]

Yep that worked.......

[james christie]

I've had the Revington ssuspension package on my 3A for about 25000km now and it makes me more enthusiastic about it every time I drive it. I fitted it to replace a clapped out original arrangement and also fitted R & P steering. The result is better roadhlding, bump steer is eliminated and the steering even self centers. This may be a touch too modern for some.......

As for cost, you pays yer money and you makes yer choice. Neil spent a lot of time developing his suspension packages and has proved them with his hand on experience, as have his customers. There aren't many suppliers around where you can buy something that has been properly tried and tested by the outfit that sells it to you ? But that comes at a price,

It would seem to me to be a mistake to buy the parts here and there just because they were cheaper.

 

FYI before going over to R&P steering, I too fitted the spring loaded peg to the original steering box and also the bronze (?) Delrin bushes. This helped a lot to tighten things up but if the bronze bushes lasted well , the spring loaded peg only puts off the day of reckoning. In my experience once the worm begins to wear there is not a lot will stop it.

 

 

James

[iain]

Bob, I'm very much thinking the same, I have the Box top and centre bushes, these made a dramatic improvement. I also swapped out the idler arm for a better original, mine can only be described as routed!. I believe Revingtons do a nice bushed version which might also be worth considering. As regards reducing the bumps steer with the new arms Peter W's analysis and feedback was very positive.

[Lebro]

Thanks for that both James & Iain.

 

My steering box is actually pretty good as they go, & I can see how the sprung peg, along with bushed pivots on the centre arm could improve things further. I am sceptical about replacing the idler, because I think it would have to be extremely sloppy before it makes any difference.

I have (this afternoon) been reading up on exactly what needs to be changed, & was surprised to read that the early vertical links can be retained. I had always thought that on the later cars one of the links (& trunnion) were the opposite thread direction. Not sure where I got that from though.

 

Anyway - still in the planning stage. Watch this space !

 

Bob.

 

P.S. James do you still have the sprung peg & bushed pins ? if so could they be for sale ?

[james christie]

Yes - I still have all the parts but am keeping all the bits and pieces including the steering box in case a future tenant wants to change it all back

 

James

[Lebro]

Fair enough !

[Drewmotty]

TR4s use the same vertical links as the side screen cars together with 3 degree trunnions and TR4a/6 top wishbones.

TR4a onward uses a beefed up vertical link with left hand thread on one side and right hand thread on the other. These later vertical links have the stub axle about an inch higher relative to the trunnion pivot bolt and so will lower the car by that amount if fitted to an earlier car.

Andrew

[Lebro]

Thanks Andrew.

So, it sounds as if I may not need the adjustable upper fulcrum, but instead use TR6 type upper wishbones on my existing fulcrum, together with the TR4 3° trunnions. would that give me 0° camber ?

 

Bob.

Edited February 1, 2016 by Lebro

[Drewmotty]

TR6 upper wishbones are the same length as the ones fitted to TR3s but offset towards the rear of the car to take account of the 3 degrees castor. They wont alter the camber.

As I understand it the adjustable fulcrum has a 12mm higher axis to help with the roll centre and camber gain. A 12mm spacer under a standard fulcrum will pull the camber in about 1 degree to +1 degree but the other one or two degrees you need for a road car with radial tyres (maybe 0 to -1 degrees) will need the sliding adjustment or shortened arms.

The adjustable fulcrum also spaces the top arms out a bit wider leaving room for shims each side of the ball joint so that the arms can be assembled without any strain on the vertical link.

Revington has thought about it more than a bit

Andrew

[Lebro]

Thanks Andrew, it's all becoming a bit clearer now.

 

Bob.

[stuart]

Im not a big fan of the brass bushes on the centre link and prefer the Moss Delrin bushes instead.

Stuart.

[Lebro]

Interesting - I would have thought brass would last longer & be more precise ?

 

Bob.

[PhilipB]

I believe OGB was Neil's test bed for his suspension package. Others can list out the techy bits and the spec etc but from the driving seat, it's hugely effective and I can only repeat James' comments except that OGB still has the steering box but with the sprung peg. I've wondered about R&P steering but once moving (5.5" rims) everyting lightens up and is just so positive and predictable with loads of feedback.

 

Recomend it

 

Phil

[Lebro]

Thanks Phil.

 

That's the way I'm heading

 

Bob.

[stuart]

Interesting - I would have thought brass would last longer & be more precise ?

 

Bob.

You probably dont want the race car feel do you?

Stuart.

[Lebro]

Hmm probably not, so how do the delrin type work, is the delrin simply a replacement for the rubber part of the original type, only the pin can rotate in the delrin ? I would not have thought that there was much give in the delrin. ?

 

Have not ordered anything yet, so just trying to make sure I get what I need.

 

Plan so far:

 

Adjustable front upper fulcrum kit TR2-6

Lower trunnion Late TR4 133838 (RH )

Lower trunnion Late TR4 133839 (LH )

Top ball joint Late TR4 - 6 GSJ131 X 2

Upper wishbone rear Late TR4-6 133507 X 2 Second hand OK

Upper wishbone front Late TR4-6 133504 X 2 Second hand OK

Steering geometry kit

Sprung peg mod for steering box

Replacement central tie rod pivots - brass or delrin ?

I'm happy that my steering box is a good un (very little play)

Also that my vertical links are good

Steering idler is a tiny bit loose on the thread, but no where near enough to make any difference to the position of NS wheel

 

Bob.

[stuart]

You are correct in your assumption of how they work, they just dont transmit like brass does being harder. The old trick to refresh the idler was grind the body down a tad so you can screw it in one more turn onto unworn threads.

Stuart.

[Lebro]

Thanks Stuart.

 

Bob.