TR4A Front shocks

[trchris]

Hi all

Has anyone fitted the KYB uprated gas filled front shock absorbers supplied from the TR shop? I am trying to cut down the scuttle shake of my 4a over the poor roads I have around here 

and make the ride a tad smoother I also intend to fit the uprated lever arm valves from Moss in the rears any thought would be appreciated 

Chris

[Malbaby]

Your front coil  springs are probably the culprit, being too hard. [Do you know their rating].

I would remove the front springs and check their rating, with the possibility of fitting softer springs along with new shocks.

[RogerH]

Hi Chris,

The front springs could be over rated and causing the stiffness. Or it could be a seized or badly adjusted shock.

What shocks have you on there at the moment - are they adjustable - if yes then slacken them off.

Can you identify the  springs - colour coding bands.  It is possible with heavy bags of sand to establish the spring rate.

Are the KYB shocks adjustable.

 

Roger

 

[trchris]

Hi Roger

The front springs were replaced in 2005 with Moss 310lb rated ones by the previous owner he also replaced the front shocks with standard ones from

TRGB also at the same time .Have removed and checked the shocks not bent or seized maybe slightly weak ?? The  KYB ones are non adjustable just gas filled and

 slightly uprated but reasonably  priced but have noticed in previous post theres a mention of size (being slightly too long) will have to confirm with the TR shop

Chris

[Z320]

Hi Chris,

are the coil springs lower than the original ones?

ciao, Marco

 

[trchris]

Hi Marco

I don't think so as the moss part number on the old original receipt is for standard 310lb front springs that's why Im suspecting the shock absorbers

hence the query regarding KYB front shock absorbers as I don't feel getting adjustable ones warrant  the cost for normal ride driving 

Chris

[Z320]

Indeed 310 lb is standard and dhould be standard long.

Do you own a pit to look and work on the front axle with the car on its wheels?

 

[trchris]

Yes I do have access to a pit and have checked most things all the joints have been replaced along with poly bushes to the top wishbones and standard rubber to the lower ones 

this is why I suspect the shocks and wanted some between standard black from usual suppliers and the adjustable ones hence seeing KYBs on offer from the TR shop I 

thought would be a good option unless told otherwise from you guys

Chris

[Z320]

The way of movement of the original front shock absorbers is very limited, only about 35  - 40 mm.

I own a pair of original Armstrongs, about 271-305 mm, a pair of period Monroes, about 258-302 mm, a pair of "suitable" Spax, about 263-310 mm.

 

You could do this experient:

drive the TR on the pit, don't lift it, keep it on the wheels,

disconnect the lower two damper brackets from the spring pan and open / pull the 7/16 bolt,

next bolt the two brackets back on the spring pan without the 7/16 bolt.

Now you can press the lower end of the damper up as much as possible and see how much way of movement you have for "down".

If this is only 5-10 mm you hop very fast on the rubber / bump stop inside the damper. That's very uncomfortable....

Ciao, Marco

Edited October 7, 2019 by Z320

[Malbaby]

310lb is standard fitment, although you could fit softer springs.

I concur with "Z320" comments on testing shock absorber travel. I fitted non TR shocks [more range of compression/extension] on my car.

Keep in mind that preferred ride height has to be considered in relation to choice of shock absorber travel.

[Z320]

One idea from tonight:

shock absorbers are only "movement dampers", they have no own compression rate.

I have only once been involved in gas absorbers, so: don't they have a own compression rate?

Then you have to add their rate to the rate of the coil spring. If this is the case - do you wat that?

With longer absorbers, perhaps in combination with a new steering rack or aluminium brackets on the rack, I would do another test:

do the coil spring pull on the track rods and bend the steering rack if you lift the front of the car?

For this disconnect the track rad balls from the axles, then lift the front of the car. Can you stick the tapered connection still together?

This all works in limited ranges.

I remember a sentence from a TR restauration book in the sence of: lower coil springs my coarse the need for modifyed lower brackets.

This is what I do at the moment because my standard springs are 25 mm lowered AND I have a new steering rack (I reported what happens)

Ciao, Marco

Edited October 8, 2019 by Z320

[trchris]

I will do the suggestions mention and let you know what I find Im not after a smooth ride as that would be impossible just one that is better than I have

The problem is Im compering the ride to the TR6 that I owned and Im sure it wasn't as stiff

Chris 

[Malbaby]

Z320 suggestion of modified lower brackets is a good idea.

[Z320]

22 hours ago, Malbaby said:

Z320 suggestion of modified lower brackets is a good idea.

Thanks, but not my idea.

I fitted the first pair of my brackets today, the dimensions suit lovely, the shock absorbers do what they have to do now, I'm very pleased with the result.

Ciao, Marco

[trchris]

OK so bit the bullet and replaced front shocks with adjustable gaz made a noticeable difference to the harsh ride now waiting for the 25% uprated lever arm replacement

valves for the rear which I will change along with 30w heavy duty fork oil will post outcome

Chris

ps noticed old units were 3cm longer than new ones

[Z320]

So you use oil filled shock absorbers of the trade mark "GAZ", not gas filled shock absorbers of KYB...

With the old ones 3 cm longer you probably hoped on their bumb stops all the time.

Could you tell us the GAZ model number, please?

Ciao, Marco

Edited October 10, 2019 by Z320

[trchris]

Hi Marco 

you might have miss understand the previous post I fitted GAZ adjustable front shocks and not the KYB ones and are uprating the rear lever arms 

Chris

[Z320]

yes I do understand, we agree with each other...

Edited October 10, 2019 by Z320

[Z320]

Hi,

that's how all 4 look now, ready to paint (no powder, please!)

Next photo expains the need for the offset of the construction and the soldered washers.

That was the plan, but pretty much more effort than I expected.

Ciao, Marco

Edited October 13, 2019 by Z320

[Z320]

Hi,

this are the new made brackets on the TR, I already drove some miles, I'm very pleased.

The old Spax squeaked horrible, now I use Monroes, got them used years ago from a friend.

I should have swaped over to them earlier.

Ciao, Marco

 

Edited November 23, 2019 by Z320

[RogerH]

On 10/10/2019 at 8:16 AM, trchris said:

ps noticed old units were 3cm longer than new ones

Hi Chris,

that was the problem found a couple pf years back by a forum poster (Richard)

Not a problem under normal driving conditions; but if you lift both front wheels off the ground the spring pan presses on the TRunion and the steering becomes quite stiff.

Both Moss and the original seller to Richard were contacted. This produced a couple of reactions but the bottom line was that nobody knew when the change  from 300mm to 330mm happened - and in that unknown time period (very possibly a couple pf decades) nobody spotted it or complained. 

Even a number of standard upgrades using Koni, Spax etc are 330mm

Roger