Triumph tr6 rear damper conversion and general suspension set up

[Fredell1977]

Dear all,

I am aware that this topic was extensively discussed but I am still undecided on what to do on my tr6. I use it for the odd track day/hill climb. I started off by wanting to fit a rear shock conversion but I was intrigued by revington's complete suspension kits ( although extremely pricey). Did anyone fit the integrated suspension package offered by rev tr?

 

As for rear shock conversion, which one should I go for? It seems that ctm have a good kit. But what about the one offered by racetorarions? Should I also change anything from the front set up if I opt for a rear shock conversion?

[TriumphV8]

Oh! Opening a can of worms!

You will receive as much opinions as there are solutions on the market.

 

I personally would recommend to check the length of damper

when fully extended and the other way when axle hits the bump stop.

It is necessary that the damper leaves a few millimetres that the bump stop can compress.

Many sets are blamed to have wrong length.

 

I tried out several conversions and ended with number 3 from Rimmer:

http://www.rimmerbros.co.uk/Item--i-GRID600135

It is the stiffest version and also reinforces the rear end.

 

I found all offered dampers being not the best quality. If not sure

I would look for an adjustable damper. SPAX looks quite nice.

 

This is a modified "number 3" and a custom made German Bilstein damper.

I had a set of 4 made to my specifications and completed it with my spring setup.

Anti roll bars on front and rear are employed.

 

[Jersey Royal]

You pay for what you get.

 

Cheers

Guy

[Steves_TR6]

I'll give racetorations my vote.

 

Their conversion kit is not cheap but the brackets are beautify made and the spax shocks of decent quality.

 

I fitted the kit to a previous 6 and then found it already fitted to my current car.

 

Fit was easy and I've not had a problem with the current car in 12000 spirited cars.

 

For sprint/hill climb fun you might consider two other things, rear anti roll bar and LSD.

 

Rear arb greatly improves rear stability,many the LSD makes a big difference to traction.

 

Hth

 

Steve

Edited October 25, 2015 by SDerbyshire

[harrytr5]

Because of the state of our roads and we are getting older the North London Group (well a few of us) have gone back to lever arms. I have tried and fitted all kits and come to the conclusion Triumph got it right the first time.This is my own personal findings and of course fit what you like. Both of my TR,s have lever arms on and ride really well My concours winning one has standard lever arms and my other has 25% uprated and both are comfortable on the road.

Track cars are of course set up differently and would I guess be a nightmare to drive on normal pot holed crappy roads.

Just my findings for what that is worth.

Regards Harry TR5 Nutter

[RogerH]

When I finished my 4A in '98 I fitted the original lever arms. These were not good almost certainly due to their age (apprx 40 years)

 

I changed to the Revington strut in coil as theory suggested they may be better. In practice I found this not so.

The actual fitting is iffy due to space constraints and the bottom attachment is also prone to mis-hap.

 

I then fitted a bracket from the TRShop - a quite large steel support (I believe German - possibly from a battleship) that fits to the original damper attachment and also a third place. Koni struts fitted. This works very well indeed.

 

However I see no reason why the original lever arm dampers should not have work perfectly well - mine were very very old.

 

Roger

[TriumphV8]

Because of the state of our roads and we are getting older the North London Group (well a few of us) have gone back to lever arms.

 

In fact opposite would be correct with good dampers.

What a good damper has to do is damping the swinging of the axle

and open the valves over a bump in the best way not to let the shock

come through to the car and make it unstable.

 

Our lever arm dampers have small valves, too small for modern expectations on dampers.

They do not allow the axle to swing in quickly when an obstacle is on the street.

The whole car will be lifted giving high load on axle and frame and pass a shock to the driver.

If thicker oil is added the things get worse altough the normal riding becomes stiffer.

This was the earlier solution on race tracks where heavy bumps have been rare.

Actually many people lock their Spaxes too much in the same way, get a very stiff road holding

but on bumps they are close to be thrown out of the car. With opened Spax riding comfort and

road holding should be a little bit better but somewhat away from what could be possible.

 

The cheap KONI do not have damping valves for bounce at all, as they have two tubes in each other

there was no space for the bump valve in the piston. Bump valve is a simple one way valve with

a reduced diametre for oil pass.

 

The Spax have small tubes and from that also only small valves.

 

To be honest both companies have high priced dampers that work perfect but not offered stock for TR.

 

So the remedy might be to ask a local supplier to have dampers manufactured like SACHS,

KW and BILSTEIN can do if you are able to specify what you want.

 

You get a perfect riding comfort close to stock but the car is stable on the street like with a vaccuum

underneath and does not get nervous when street gets bad.

 

Anyway with the levers the owner is in a one way street, all the reinforced ones I bought have not

been worth the money spent, but with telescopic dampers it is possible to participate in the modern

damper development because that is the technic all use.

[ijonsson]

I had my front dampers made by this company http://www.protechshocks.co.uk/

[Steves_TR6]

Very interesting post by Andreas, and interesting link from Inge !

 

My gas spax shocks are looking tired so someday I'll replace them.

 

I like the idea of the bespoke ones in your Link Inge, but as a suspension numpty how would I know what model / specification to go with??

 

Steve

Edited October 25, 2015 by SDerbyshire

[TriumphV8]

Steve, if you go for Inges solution and they are really good dampers

you only have to get close to the perfect damping rates.

Get it softer than estimated and with the independent bump/rebound setup

you can get closer to the individual perfect solution.

[ijonsson]

Very interesting post by Andreas, and interesting link from Inge !

 

My gas spax shocks are looking tired so someday I'll replace them.

 

I like the idea of the bespoke ones in your Link Inge, but as a suspension numpty how would I know what model / specification to go with??

 

Steve

I had old shocks to take measures from.

/Inge

[Andy Moltu]

I would go for the type that mounts back to the original mounting on the chassis. The version sold by many does this and also has a bolt that goes through the wheel arch for extra strength (I got mine from the TR shop they do two versions - one in alloy which I think has TUV approval and a version in mild steel)

 

The Rimmers version 3 is an old design - the first of which to transfer the load back to the original mounts but is a pain to fit.

 

The Revington ones ideally need the upper part of the chassis cross member reinforcing as they use a relatively short shocker which has to offer more resistance as it does its damping through a shorter range of travel compared to the others which attach to the original shocker mount on the trailing arm.

[HarveyCoppock]

I have something like the type 2 steel - just brackets back to the chassis lever arm mounting point - with Konis, but tyres sometimes rub slightly - 185s though. Main reason I changed was lever arms always coming loose... though that was probably not their fault. Put a locking nut on the back of the bolt through the chassis this time, though that's not in the parts book.

[stuart]

I have something like the type 2 steel - just brackets back to the chassis lever arm mounting point - with Konis, but tyres sometimes rub slightly - 185s though. Main reason I changed was lever arms always coming loose... though that was probably not their fault. Put a locking nut on the back of the bolt through the chassis this time, though that's not in the parts book.

Thats the point of the type 3 brackets as they allow for wider wheel/tyre combination and different offsets too without rubbing.

Stuart.

[RogerH]

Hi Harry,

I had a problem on my 4A where the tyres rubbed on the koni struts - (165 tyres).

The quick fix was a 6mm spacer - quick was about 5 years.

 

However this year I had all my wheels measured and the rears had a far too much negative camber (tops leaning in).

I sorted the camber - new TA brackets and 3 hard days work.

 

If I had to do it again I would probably go back to new, quality lever arm dampers.

 

Roger

[Fredell1977]

Dear all. Thanks for the feedback

[HarveyCoppock]

Investigating a knock from rear end, over bumps, gets worse as car warms up, can't find a thing wrong, t/arm bushes a bit rough perhaps, but I can feel it most through the body of the Koni dampers, these are on a fabricated steel bracket onto the chassis. Anyone else had these do this? I might have to go back to lever arms, seeing as they rub on the 185s slightly anyhow.

[stuart]

Investigating a knock from rear end, over bumps, gets worse as car warms up, can't find a thing wrong, t/arm bushes a bit rough perhaps, but I can feel it most through the body of the Koni dampers, these are on a fabricated steel bracket onto the chassis. Anyone else had these do this? I might have to go back to lever arms, seeing as they rub on the 185s slightly anyhow.

If they are rubbing at all then change them immediately.

Stuart.

[HarveyCoppock]

Thanks Stuart, think I will, its just on full deflection and not ripping the tyre up but still, don't think I'd give it a test like that. Main reason I changed to telescopics was that I could never keep the lever arm fastening bolts tight, though I did just have a normal spring washer under the bolts.... - the part number for this doesn't appear to be a normal spring washer... The telescopics brackets I put locknuts on the back.

 

I have the old ones still - will prob exchange them.

[TriumphV8]

It is all not plug and play.

 

Although telescopic dampers can be superior to the levers

all the setup must be done properly to obtain good benefit.

That is why so many people claim levers being better and go back.

They simply could not tweak all the details to make it right.

 

As I have the 205/65 15 on 6" together with bigger telescopic dampers

fitted and nothing rubs that must be possible at 185-15 without trouble.

 

First the camber of the rear must be set properly and also the toe in.

Both has big influence on the space in the damper area. If nothing

helps the wheels should be checked for spacers. If they still fit nicely

under the wheelarch that is an option, too.

 

As many dampers are on the market that have the wrong length I would

check that by removing the spring and compress the rear to the bump stops

and test if the dampers are short enough not to block.

 

Just from my experiende I can tell it is possible to get a Triumph that has

the comfort of the weakest dampers yet driven and also a perfect roadholding

without jumping on dimples with a good modern damper.

All that fiddeling with the damper setup becomes less important when both

comfort and good roadholding are offered from one modern damper.

[stuart]

Thanks Stuart, think I will, its just on full deflection and not ripping the tyre up but still, don't think I'd give it a test like that. Main reason I changed to telescopics was that I could never keep the lever arm fastening bolts tight, though I did just have a normal spring washer under the bolts.... - the part number for this doesn't appear to be a normal spring washer... The telescopics brackets I put locknuts on the back.

 

I have the old ones still - will prob exchange them.

I tend to fit lever arm shocks with longer bolts and then fit extra nuts on the back side to lock them in, that way they dont come loose. Often the thread in the chassis mounting block is worn which doesnt help either.

Stuart.

[Tim D.]

+1 on extra bolts. Also for tube shock conversions that use the existing bracket.

Tim