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PaulAA

TR6 ride height

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Chaps

I know this will probably attract howls of laughter, but...

I have 195/70-section tyres on the '6 and the rolling circumference is almost identical to the 185s that were standard on the US cars (which it is).  But the car sits high (27" ground to top of the wheel arch front and rear).  Since the rear end is being dismantled, I am tempted to take the opportunity to swap to uprated springs and lose an inch of that height front and rear.

I know that this will mean that I slap the straight silencer boxes on ramps and sleeping policemen more frequently, but does anybody hereabouts have experience of living with lowered springs?  Is it a real handicap?  Is it the pure folly that my son predicts it will be..?

Comments and advice welcome.

Paul

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What problem are you trying to resolve?  Is it purely visual "arch gap" or are you wanting a lower COG and stiffer springs for handling reasons.  My thinking is that you may sacrifice "comfort" (all relative!) and ground clearance for minimal gain.  Two caveats being.....

I'm no TR6 expert and have only driven one - a bog standard and very original early UK car which suffered the most amazing "squat" under even moderate acceleration that I have ever encountered.  Damping also seemed minimal but not doubt the original lever arms were still in place.

I swapped the standard front springs and Spax dampers (adjustable but set near minimum) for 330lb  (50% uprate) TT springs and Koni dampers (adjustable, set to 25%) and achieved a marked improvement in ride quality.  This doubtless "because Koni" with the Spax managing to be both harsh and wallowy somehow.  I could have tried turning them so they were just harsh I suppose.....  If buying Konis (and maybe springs) I suggest Bastuck as they are less expensive, even with a pig-sick pound.  Though perhaps as you are starting in Euros the reverse applies.....

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Thanks, Nick

The reason is two-fold.  Firstly, to reduce roll and pitch and secondly to improve appearance.  There is indeed a lot of give in the rear suspension under acceleration, resulting in considerable squat.  The springs are relatively new and I'm hoping that uprated springs will reduce this.

Paul

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Hi Paul, I have the tr shop springs which are slightly lower and uprated (Front TT4001PR: Fitted Length 6,65, 390 Lbs/in and Rear TT4212PR: Fitted Length 8,85, 420 lbs/in) Boxed up as Classic Gold. The stance I’m very happy with and I have no problems with speed humps. I have 25% uprated rear lever arms and standard shocks on the front, which I may change to koni’s later. No real squat and the ride is comfortable for me, in comparison with my Z4 with 18” wheels it’s about the same. I have 165 x 15 Michelin XAS tyres. I have the standard exhaust system.

887AFBF1-6D20-43C1-9077-724B4D5CAFD8.jpeg.535cee8a063a318fa4ddeb3398dd1a9f.jpeg

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I bought a TR6 fitted with shorter stiffer springs. Complete pain, front , middle and rear all smacked speed bumps and one street I drove down frequently had three sets of speed bumps. Ok possible to live with that but driving along a street and approaching a speed bump I would slow right down and the number of times a car behind me who had not been paying attention almost came in the boot. Things had to change. I went though three sets of new springs each longer than the last set. Eventually I ended up with the original lengths which were not easy to find.

These were softer than the intermediate sets however the road handling of the car vastly improved, I can take speed bumps at 30mph with no issues. On the rubbish roads around here with potholes particularly whilst cornering the car handles must better staying on track even if there is a wayward tyre exploring a deep pothole. Whilst driving over a pothole the tyres /wheels drop then hit the rear of the pothole and climb out and the impact on the car is much less. With hard suspension potholes kicked the car very hard and seemed to have an effect on the remaining tyres unsettling them whist they were still trying to grip the road particularly in the wet.

So on rubbish public roads I think my TR6's handling has improved - think of the suspension on off-road rally cars. However I have absolutely no doubt that on good quality roads, or tracks a lower ride height with stiffer suspension would be a definite advantage.

By the way if you change the height of the springs spend two minutes measuring the suspension travel and ensure that the range of suspension travel is within the operating range of the shocks. Mine wasn't and the shocks topped-out - dangerous as it "lifts" a wheel off the road. I had longer shocks made and they actually cost less than the "standard" product from the same manufacturer at the usual stockists.

Alan

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Thanks, Kev - very helpful.

I see that the TT4001PR / TT4212PR is currently not available through any of the usual sources, so this might be longer-term plan.  I checked the front tyres on full-lock and it does look to me as if the uprated springs, at 1" shorter, might result in the tyre contacting the wing when the suspension is partially compressed (such as mounting a kerb).

Thanks for the comment about shocks, Alan - are you willing to say which make you ended up with?

Cheers

Paul

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Paul,

 

Gaz and delivered in ten days of order,

Alan

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Paul,  if squat under acceleration was significantly greater than dive under braking, when the acceleration under the second is greater (when pushed hard), then the front and rear springs are out of balance.  Stiffer rears required.

Dampers will not prevent squat, or dive, they will delay them, but worth considering stiffer dampers too for transients like these.

John

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Hi Paul,

 

Before the Club Triumph 10 Countries Run I fitted some new road springs from Revington TR, these being recommended by my mate, Tom Keys

Front: RTR3665 540lb/in 224mm free length

Rear: RTR3666 600lb/in 257mm free length

These fitted in conjunction with Koni telescopic dampers and TUV rear brackets have made a very good contribution to the way my TR6 handles, the car now drives very predictably and was a delight in Dolomites.

Only snag, price of the springs from Revington TR, still fit and forget!

 

Pic below is one of her parked, looks like she has a touch of positive camber at the front???

IMG-20190906-WA0000.jpeg

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Neil is not shy with his pricing......

But if we know the rate and free length we can ring Faulkner springs, who are very reasonable......

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On 10/24/2019 at 11:54 AM, JohnD said:

Paul,  if squat under acceleration was significantly greater than dive under braking, when the acceleration under the second is greater (when pushed hard), then the front and rear springs are out of balance.  Stiffer rears required.

Dampers will not prevent squat, or dive, they will delay them, but worth considering stiffer dampers too for transients like these.

John

John

Thanks for this.  The car currently has standard 310lb front / 350lb rear springs, but the squat under acceleration appears to be significantly greater than the dive under braking.  One of the question (a rhetorical one, I admit) is whether the uprated rears, at 420lb, would help to keep the silencers off the deck when accelerating up the exit ramp from the underground parking where the car lives...

My spanner man visibly shuddered when I discussed changing the original spec with him last week.  But ground clearance when loaded with 85kg of Junior and 80kg of me is still 6"/15cm to the lowest point of the exhaust pipes.  Hell's teeth, worth a try.

Paul

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Paul, in the situation described, you have the sudden change of angle, from floor to.slope, as well as acceleration, but I suspect the first is more to blame.     Would slightly shorter tail pipes help?

Jo VM

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John

The point of contact is the end of the silencer box, as in the picture below.  Trouble is, it's tight to the boot floor so there's no space above it and it's tight to the rear suspension, so there's no room to bring it forward.  In the spirit of our simian ancestry, it is a bit of a baboon's rear end and I think that replacing these two hanging... things... with a conventional cross box and side exit is becoming a necessity.

Paul

DSC_4098.thumb.jpg.39f22d77a48f42cf3418ea2001583e12.jpg

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That looks pretty well tucked up for one of those......

Even though the up-rated springs may give a resting height lower than standard, the increased rate means that it may not end up lower when laden/under acceleration.......

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Thanks, Nick - that's my guesstimate.

However, I have just become slightly confused... for the rear, I ordered Rimmers part 216275UR, which their nice chap on the 'phone told me is approx. 3/4" lowered.  However, English parts describe 216275UR as spec TT4212PR, uprated to 420lb, but standard ride height.

For the front, I ordered Rimmers part 213165UR, which Rimmers state is 1" lowered, but which other websites also describe as 'stock ride height'.

My aim is to slightly lower the car evenly and increase the spring rate, but I am not clear whether I have ordered the correct springs to achieve this...

Paul

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Yeah...... confusions reigns...... as usual.  I don't really have anything useful to add except to say that is sticking with the standard (well-used preseumably) dampers, you may find things a bit under-damped

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18 hours ago, PaulAA said:

John

The point of contact is the end of the silencer box, as in the picture below.  Trouble is, it's tight to the boot floor so there's no space above it and it's tight to the rear suspension, so there's no room to bring it forward.  In the spirit of our simian ancestry, it is a bit of a baboon's rear end and I think that replacing these two hanging... things... with a conventional cross box and side exit is becoming a necessity.

Paul

DSC_4098.thumb.jpg.39f22d77a48f42cf3418ea2001583e12.jpg

Ah!    You have the blue, no doubt contact will provide some red!   And I can see that how you are thinking will be the best way forward.    As it were.

John

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Paul,

Whilst trying to sort out my TR6 springs I started a database as I was so confused.

FromTR Register

 

 

 

 

 

Front

 

 

inches

MM

 

Stock

Grey

312

6.75

171

 

tt4006

B

390

6.9

175

 

tt4001

WB

390

6.65

169

Fitted May 2015

tt4201

PB

420

6.5

165

 

tt4102

PY

420

5.75

146

 

tt4207

OB

450

6

152

 

 

 

 

 

 

 

Rear

 

 

 

 

 

Standard

GW

354

8.81

224

 

TT4212

GYY

420

8.65

220

Fitted May 2015

TT4211

WY

390

9.5

241

 

TT4215

RY

510

8.25

210

 

TT4215A

PY

550

7.45

189

 

 

 

 

 

 

 

Recommended pairings

 

 

 

 

Raised

TT4406

TT4211

 

 

 

Standard

TT4001

TT4212

 

 

 

Lowered Road

TT4201

TT4216

 

 

 

Sprint

TT4102

TT4215a/6

 

 

 

           
           

Revington

 

 

 

 

 

Front

 

 

 

 

 

RTR3336

WB

390

9

229

15% uplift

RTR3064

PB

420

9 1/4

235

30% uplift

RTR3192

RB

400

9 3/8

238

uprated 120 to 130mm ground clearance

RTR3665

BB

540

8.82

224

V fast road

RTR3140A

YO

650

7 1/2

191

 

RTR3140B

BYY

650

7 3/4

197

 

RTR3140C

YB

650

8

203

 

RTR3140D

YG

650

8 1/4

210

 

RTR3140E

YW

650

8 1/2

216

 

 

 

 

 

 

 

 

 

 

 

 

 

Rear

 

 

 

 

 

RTR3264

RYY

510

9 7/8

251

Hillclimb / Sprint

RTR3191

GYY

540

10 1/2

267

Hillclimb / Sprint use with RTR3665

RTR3666

ltB/W

600

10.12

257

rally

RTR3193

ltP/W

550

8 3/4

222

Vfast road

RTR3101R

RY

450

10 1/2

267

135 to 145 mm ground clearance

RTR3504

YY

420

10 1/4

260

 

 

 

 

 

 

 

Revington Recommended

 

 

 

 

RTR3192

RB

400

9 3/8

238

uprated 120 to 130mm ground clearance

RTR3101R

RY

450

10 1/2

267

135 to 145 mm ground clearance

           

Rimmer recommended:-

 

 

 

 

front

 

420

9.25

235

 

rear

 

420

11.02

280

 

 

 

 

 

 

 
           

Moss

 

 

 

 

 

Adam Chignell

 

 

 

 

 

When you say "enhanced ground clearance" do you mean lowered or raised ? our uprated springs are lowered. We don’t list the free length of the springs because two springs may be the same free length but different poundage, thus when compressed will become different length. We list the compressed lengths of these springs (cars weight).

 

Moss recommended:-

 

 

 

 

TT4201PR front fast road

 

420

6.5" compressed length. Standard length 6.75"

front fast road

>TT4216PR rear fast road, 420lbs 8.65" compressed length. Standard length 9"

420

8.65" compressed length. Standard length 9"

rear fast road

 

However once fitted the best £25 I have ever spent was on getting the car corner weighed and balanced it really made such a difference that weight distribution was even across the wheels.

 

Alan

 

 

 

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1 hour ago, JohnD said:

Ah!    You have the blue, no doubt contact will provide some red!   And I can see that how you are thinking will be the best way forward.    As it were.

John

Spot (or is that 'blemish') on, John!

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Alan

Many thanks for sharing your spreadsheet.  As I posted last night, there seems to be some disagreement amongst suppliers regarding which TT specification correlates with which six-digit catalogue reference.

I will be significantly chaffed if 216275UR (rear) and 213165UR (front) don't turn out to be uprated and slightly lowered...

Paul

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26 minutes ago, PaulAA said:

Spot (or is that 'blemish') on, John!

Those colours are just beautiful!    To a baboon.

John

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44 minutes ago, JohnD said:

Those colours are just beautiful!    To a baboon

!Wah!
15552000.jpg

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19 minutes ago, Nick Jones said:

!Wah!
15552000.jpg

Viewed from the rear, mine are bigger.  So to speak.

And both have a slight indent on the bottom.  Not sure whether that is a genetic or a generic thing... but I blame the garage ramp.

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Paul,

Could I also respectfully suggest that when you springs arrive you place alongside each other and ensue they are the same length - one set I was sent was at least 1/2" difference - they went back presumably resold to the next man.

1/2" of spring rated at 300lb would be 150lb difference when the car was parked this became quite apparent when my car was corner weighed.

For example if there is a 75lb difference between the two front wheels how would that effect tyre adhesion under braking or cornering? It starts by getting  each axle springs the same length.

Many / most springs I worked though on my car suspension where built from the same gauge wire just different lengths coiled to the same diameters, the shorter the spring the stiffer so that any small difference in length produces a large variation in the lb/inch rating and you really do need an axle  "pair" as the starting point for good suspension.

 

Alan

 

 

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Mmmmmmmmmmmmmmmmmmmmm!

Hubba hubba!

Image result for baboon selfie

Don't post any more of those, Paul, you'll have the ladies fainting in droves!

Edited by JohnD

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