TR6 Lowering

[matt george]

Hi guys,

 

I spotted the attached '6 for sale at Classic Marques, and I really like the stance/ride height. According to their blurb, this is achieved with 1 inch lowering springs. I'd like to do something similar with my car.My question is then, has anybody on here done similar? I'm assuming yes, so is it easy to do, is it easily done just by changing to uprated springs, or do the dampers need changing too? Particular makes or kits would be good. Opinions much appreciated

 

Cheers,

 

Matt

[harrytr5]

May look good but will play hell with the speed bumps.When I last moved I could not get in my driveway as it sloped down from the pavement and had a slight bump in it.I had to spread concrete on my driveway to get in(my then 1969 tr6)This stayed like this till I could afford to have the driveway raised along with the attached garage and garden.It is all now a block oversite and I can get about six cars on.I do have a double garage at the back which I get to play in though!So think twice about lowering,been there,got the t-shirt and would not lower again.

Regards Harry TR5 Nutter

[matt george]

Interesting point Harry. Surely a 1 inch drop wouldn't make that much of a difference though? There is an incline into the lock-up where I keep my '6 actually, so worth bearing in mind. The main reason I'm considering lowering is that I'm thinking about de-bumpering and just think it would all marry up better with less of a gap between wheels/wheelarch etc?

 

Cheers,

 

Matt

Edited December 8, 2010 by matt george

[harrytr5]

Interesting point Harry. Surely a 1 inch drop wouldn't make that much of a difference though? There is an incline into the lock-up where I keep my '6 actually, so worth bearing in mind. The main reason I'm considering lowering is that I'm thinking about de-bumpering and just think it would all marry up better with less of a gap between wheels/wheelarch etc?

 

Cheers,

 

Matt

 

 

Hi Matt,

Measure the height between the chassis and the road(along the lines of the outer sills) then deduct that 1".See, not a lot of clearance is there!If you can have a drive/talk to a fellow club member it could help you decide.I hope someone else will respond to your question on here.

Rgards Harry TR5 Nutter

[Alec Pringle]

Hi Matt,

 

1" drop in ride height makes one heck of a difference to ground clearance - means you have to be very cautious even with just a driver on board, 2 up and luggage and speed bumps can become a terminal obstruction, and the suspension all too soon runs out of travel at speed.

 

I went through this routine back in the 70s, lowering the car worked well enough on the track, on the road it was a liability even then - before speed bumps and potholes were as common a hazard as they are today ! As the car was more often used loaded than not, I finished up raising the front 1/2" and the back 1", with 20% stiffer than standard springs . . . . which distinctly improved laden handling over factory issue.

 

Cosmetic appearance isn't everything . . . .

 

Cheers,

 

Alec

[matt george]

Hi Matt,

 

1" drop in ride height makes one heck of a difference to ground clearance - means you have to be very cautious even with just a driver on board, 2 up and luggage and speed bumps can become a terminal obstruction, and the suspension all too soon runs out of travel at speed.

 

I went through this routine back in the 70s, lowering the car worked well enough on the track, on the road it was a liability even then - before speed bumps and potholes were as common a hazard as they are today ! As the car was more often used loaded than not, I finished up raising the front 1/2" and the back 1", with 20% stiffer than standard springs . . . . which distinctly improved laden handling over factory issue.

 

Cosmetic appearance isn't everything . . . .

 

Cheers,

 

Alec

 

 

Alec,

 

That's a very good point, as I expect I'll be fairly laden on the way to events etc. So yes, may have to leave as is for now..

 

Cheers,

 

Matt

[RobinTR6]

Also been there twice now with two different cars. I agree the look is great but Harry and Alec are correct it makes a big difference to grounding the car, often the bump stops were so hard pressed (in) that I couldnt remove them to replace. In addition and the thing that finally made me go back to standard ride height was the breaking of two trailing arms where the shock is mounted at the bottom, sheared off whe I hit a pot hole, and a deep undulation in the road. I cant say that the cornering ability was noticeably better with the lowered springs at normal speeds (love the look tho)

 

robin

[matt george]

I agree Robin, I think the look is fabulous. Though that said, it may be the 'lose the bumper, but keep the chin spoiler' element that's pushing my buttons. I think some messing about with that side of the car is in order first, before I jump into doing the suspension. Like you mention, I think it rides pretty well already, so not rushing to change that really,

 

Matt

[jerrytr5]

It's easy enough to change just by replacing springs, but lowered springs will also require a readjustment of the camber, which again is not difficult but something to bear in mind.

From my notes when I was experimenting with my 5:

Standard springs: ride height 700mm (measured from ground to lip of wheelarch at wheel centre line).

420lb lowered springs: ride height 650mm - Bottoms out & clouts exhaust.

420lb front/450lb rear: 645mm front/665mm rear - OK but clouts rear ARB on rough roads.

400lb front + 12mm spacer/450lb rear + 14mm spacer: 665mm front/675mm rear.

 

So, you could drop it 35mm, but bear in mind what others have said and also that the spring rate will affect how ofton you bottom out.

And that photo you posted - looks like it has positive camber at the rear but could just be the camera angle.

Jerry

[Stag powered]

I used to run 1 inch lowered springs on my TR250. depending on the aspect ratio of the tyres fitted it used to give 4 1/4 inches of ground clearance, but after a few years as the springs sagged it was down to 3 3/4 which was a pain so I replaced the springs again and shortly afterwards the local council fitted these bloody stupid square humps all over the roads in Stafford. I found that the only way I could get into town on one road was to run two wheels down the footpath I could not get between the humps as the sills caught. I actually got as far as taking a long piece of wood and a tape measure as I was certain they were over the 4 inch maximum. It turned out they were only 3 1/2 inches but with the pronounced camber on the road I was grounding out anyway. I admitted defeat and bought new standard ride height springs. At least I can load it up now and still keep my exhaust attatched.

Neil

[Chris59]

"Gendarmes couchés", "dos d'äne", "ralentisseurs", "coussins berlinois" (all in French),..... or "speed bumps" : if somebody drive a lowered TR, I think life will become very complicated .

 

Chris.

[Mike Goldthorpe]

I found spirited driving in my standard height TR6 could result in the exhaust bottoming out....sometimes to the extent that the silencer was removed :-) Admit a slightly lower stance looks good but roads are not racetracks and so a compromise has to be made....

[Peter Cobbold]

Lowering must be accompanied by stiffening the springs to absolutely avoid bottoming ( ie suspension movement going solid against the bump stop in a bend ). In a bend, once a corner bottoms all the cornering force goes onto that one tyre, usually outer rear. Result: a very fast, sudden, uncontrollable spin the likes of which you would not want to experience a second time.

So no chopping an inch of standard springs please!

I found a rear anti-roll bar was necessary too.

[matt george]

Lowering must be accompanied by stiffening the springs to absolutely avoid bottoming ( ie suspension movement going solid against the bump stop in a bend ). In a bend, once a corner bottoms all the cornering force goes onto that one tyre, usually outer rear. Result: a very fast, sudden, uncontrollable spin the likes of which you would not want to experience a second time.

So no chopping an inch of standard springs please!

I found a rear anti-roll bar was necessary too.

 

 

Peter, I absolutely agree, cut springs are for cowboys. If I do this, it will be done properly. I had a VW Transporter van of all things, that had been lowered 40mm - same amount of coils, just wound tighter, compressed etc - that worked really well. Certainly cornered like no other van I've ever driven anyway! I'd assume that any springs to go on a TR would work much the same way. More research needed methinks...

 

Cheers,

 

Matt

[RobIsaacson]

Hi

 

Mines lowered and I think it's about an inch, and yes springs uprated. I'm going back a few years so can't remember the finer details.

 

The front was a simple case of replacing springs but at the back the trailing arm mounting brackets needed to be changed to correct the camber. Something to do with different brackets, 1 or 3 notches at the top going to the inner or outer and stuff.

I've had 4 wheel alignment carried out as well but can't remember if it was related to this.

 

I got mine from TRGB who advised everything required. Give them a call.

 

Regards

 

Rob

[Davidw]

Afternoon all. I did this last year and fitted TT4001 & 4216 springs (about 25% uprated I believe) which I got from TR shop along with all new poly bushes. The only bushes I did not change were the diff mounts and the Trailing arm bushes. I also fitted new standard Lever Arm shocks (I think the originals were a little tired but there was no comment from the MOT man) on the back as recommended to me by Mark Pattinson at Enginuity about 10 years ago.

 

Obviously, it's impossible to say what brought about the improvement but it literally transformed the car. I think the ride height was lower by about 3/4". On the Yorkshire weekend I did have a few issues with the car bottoming on rough country lanes at speed (i.e 40MPH plus). On my return I replaced the TR Shop top spring collar (about 8mm) with a Superpro 16mm one to reduce the incidence of bottoming. I still have to be a bit circumspect at humps but since the change the ride & handling have been fantastic and I believe it's a price worth paying.

 

It's a long, involved job and the creaking noises the springs make as you wind up the compressor to fasten the wishbones to the pan are seriously scary, but I'm glad I did it.

 

Hope this helps.

[Mike Goldthorpe]

Regarding camber changes, I'd be tempted to use Goodparts adjustable brackets. After having done the bracket swapping thing on my TR6, I got a set of adjustabe brackets and wish I had done that earlier! So much easier and a lot more adjustment on offer (obviously).

http://www.goodparts.com/shop/index.php?categoryID=13

[TONYL]

Hi

Mine is lowered by around the 1" mark

Uprated springs all round from Moss

The back springs are fitted with rubber coil spacers used by caravaners to stop total bottoming out - they are quite free under normal use but takes the bottoming out away from the chassis bump stops.

My main problem was rebound going over bumps at low speed on the front end

The standard shockers were new but little damping on rebound causing the exhaust at the front to catch on the rebound

Fitted spax to front and no more probs - Spax on back as well - settings only just of the soft setting

 

Hope this helps

Tony

[67_gt6]

The main reason I'm considering lowering is that I'm thinking about de-bumpering and just think it would all marry up better with less of a gap between wheels/wheelarch etc?

 

 

What size tyres do you use Matt? Lots of people seem to go with wider/lower profile tyres than standard as they are easier to get hold of, but they can make the car look as if it has excessive gaps. I refitted mine with 185/70 tyres and am much happier with the way it looks, springs are standard fitted length.

 

Andy

 

[matt george]

Andy, that's another good point. Unfortunately I can't have a look at the car to check tyres, as it's currently sat 120 miles away from me in Bradford I believe they are standard profile however. They seem to fill the arches pretty well anyway.

 

Cheers,

 

Matt

[jellison]

Definately loose the bumpers on ANY TR.

 

The car looks WAY faster without and will even be a tad faster as they weigh a ton!

 

As for the lowering - what has speed humps got to do with it (you are mean't to go over these Slowly!) so should not be an issue.

 

Just remember if you lower the car all the caster, toe and camber will need to be check and put back to the pre-lowering spec or the tyres will get shot reall fast.

 

Not sure I'd go 1" lower as spring length (even if a heavier spring) gives more "compliance", I'd go for maybe 1/2" lower sport type lb'age spring and a bottom wishbone spacer kit.

 

That way you get the 1" but have a longer spring for the same low height

 

Edited December 15, 2010 by jellison