Improving a Vitesse 2L Rear Suspension

[SixasStandard]

Hello All,

As a newbie to the Forum who is currently looking for a Vitesse Saloon I would be very interested in peoples' views and experiences with the differing rear suspension set-ups of the Mk1 and Mk2 iterations of the 2L cars.

I have been focused on the purchase of a Mk2 based largely on the horror stories that you read regarding the 'tuck in' issues experienced by the Mk1. However, if owners of both cars could give me their views on this issue, then I would be able to make a more informed opinion. I am particularly interested in what options are available to improve the stock Mk1 arrangement to make it handle better at the limit, and what benefits are delivered by a CV conversion over a standard Rotoflex set up on the Mk2.

Any information/views/general abuse gratefully received.

Ian

 

[Nigel Clark]

Hi Ian, and welcome! 

The horror stories of Triumph swing axle tuck under and snap oversteer have been overstated, though that's just my opinion,  others may disagree. Snap oversteer is most likely to happen when a driver enters a bend too fast,  panics,  and lifts off mid-corner. Lifting off gives weight transfer to the front, allowing rear wheel tuck under. Driven sensibly under road conditions (not race  track), there's unlikely to be a problem. 

That said, the main suppliers offer conversion kits with the later swing spring and a stiffer front anti roll bar for those who want to make earlier cars handle more predictably on the limit. So don't be put off owning an earlier Vitesse would be my advice.

Nigel

[SixasStandard]

Thanks Nigel,

That's just the sort of information I'm looking for.

Regards,

Ian

[Colin Lindsay]

20 minutes ago, Nigel Clark said:

The horror stories of Triumph swing axle tuck under and snap oversteer have been overstated, though that's just my opinion,  others may disagree. Snap oversteer is most likely to happen when a driver enters a bend too fast,  panics,  and lifts off mid-corner. Lifting off gives weight transfer to the front, allowing rear wheel tuck under. Driven sensibly under road conditions (not race  track), there's unlikely to be a problem. 

Lots of people, especially non-Triumph owners, know all about this, but few have ever actually seen it. 'They've just heard' is all you get. Every Motoring magazine that reviews our cars harks back to journalists pushing the cars to the limit, finding where they break away, and making an entire meal of it - usually by adding: 'but this has mostly been sorted nowadays' as if generations of owners have eradicated a problem. I've never had bother with any GT6 I've ever owned and as Nigel says you don't lift off mid-corner; judge the corner and your speed, enter the corner slowly enough, and accelerate away so that the car pulls you through the bend. 

I had a slight hoo-hah a few years back when I misjudged a corner at speed - I thought the road went straight ahead when in fact it was a slip road I could see, and the main road went round a very tight left-hand bend. I steered frantically at the last minute and the GT6 went round with not even a skid. Scared the life out of me, but the car was faultless.

[johny]

I can confirm that the famous tuck under is quite real as many moons ago in a Mk1 Vitesse I went into a large roundabout too fast and panicked about a quarter of the way round (I intended to go straight across) and lifted off the throttle. Well the car flipped over so quickly, thankfully only onto its side, that it must have been down to the rear wheel tucking under. Contributing factors could have been the dry road surface (so the tyre gripped rather than slide) and worn suspension components but it was certainly very easily done.....

[Clive]

On a MK1 vitesse I would fit a courier spring with a lowering block. I did this on a herald estate,band that car handled beautifully (used for autotesting and autosolos, so handling was really tested on the limit, plus lots of road rallies where I often had to make up time)

 

Rotoflex is essentially a rubber ring in the driveshaft, allowing use of a lower wishbone. This stops large camber changes. However decent rubber rotoflexes are extortionately priced, and a CV shaft is a modern, bombproof replacement. Richard has the CV shafts off my spitfire (changed when I fitted a stronger diff, but my car is pushing the limits of the original design, a fairly std car is fine)

 

[SixasStandard]

Thanks Colin/Johny/Clive,

It seems that axle tuck under and snap oversteer are alive and well if you're 'giving it the beans' and then find that the 'beans' run out mid manoeuvre. Forewarned is definitely forearmed!!

Clive, I assume the significance of the Courier spring is a higher spring rate to cope with a commercial payload? If such a spring were to be used on a Mk1 would it potentially make the ride a bit harsh? Also, what is the availability of these Courier springs like? or are we talking modern repros?

Regards,

Ian 

 

[Pete Lewis]

on my rorty Vit6  saloon we tried a swing spring  , too soft   it just got lower and lower till it sat on the  tele shocker bump stops which we removed and it just continued down with 10deg  camber   looked hairy  , it  had to come off as ride was terrible ( it was a vitesse kit from a reputable supplier) 

next was a courier spring and 1" lowering block.....on ralis 

got mine from rarebits4 classics but bill is not trading now , i dont know of his supplier , there was a min batch requirement of 10 i reacall

Pete

 

[Colin Lindsay]

Part number 305686 if you can find any... and at present I can't.

If I could find the actual spec - number of leaves and thicknesses - I suppose it's possible one could be remade, but it would cost a bit.

[Pete Lewis]

not on mick dolphins lists

always a place to look for well price originals 

http://www.mickdolphin.co.uk/

[Steve P]

Personally i prefer the front grill and headlamp surrounds of the MK 1.Some of my experiences...

I have a brand new Courier spring sitting in my garage that i bought some years ago,fitted it to my Vitesse to compare with the one on there, which is a Triumphtune unit i bought in 1986 in Richmond.Advertised as uprated and De-cambered.(Owned the car since 1985 when i was 19).

I also have one of their Rear anti roll bar kits which never made it on to the car.

I may not have let the courier spring settle and i don`t remember what lowering block i used,but the ride height and positive camber were terrible,i swapped it back very soon after.

May re-visit it as the years advance but my car (Mk 1 Convertible 2.5L 170BHP) handles like a go cart.It also has 6 inch period Revolution wheels.Avo front adjustable ride height

shocks and 600lb springs.

I converted to the Jones/Bowler Rover/Volvo CV setup for the shafts,but only because a rear wheel overtook me in Cornwall when a driveshaft snapped at the hub end.

Steve

[SixasStandard]

Hello Steve,

That's quite a fire breathing Vitesse you have there!! Did you keep the original engine block and replace the crank and pistons for 2.5 versions? or do a straight swap with a complete 2.5L engine? To get 170 BHP I imagine that you're running a PI system?

Ian 

[Steve P]

Hello Ian,

It was a PI engine but it has HS6 carbs,TR5 cam,123 tune Distributor.Saloon overdrive box as well with a 3.27.diff.

The head and inlet manifold were modified by a well known tuner from Estonia.

All balanced when built.I just fitted a paddle type clutch as the old AP on wore out prematurely.

I was lucky to find a `Mike the Pipe` 6-3-1 manifold,which is a work of art, and i had a system made by Matt Simpson of BTCC fame as he`s near me.

It had 172 BHP on the rolling road after run in.

Don`t know what it has now 5 years later but,this summer i took it down Staines bypass which is near where i live,nothing on the road so i booted it,there was a man behind me in a Jag XF V8,at the next lights he pulled alongside me and wound the window down and said "you must have a V8 in that".

Made me smile, as it does whenever i drive it which i do all year round.

Steve

[johny]

3 hours ago, SixasStandard said:

Thanks Colin/Johny/Clive,

It seems that axle tuck under and snap oversteer are alive and well if you're 'giving it the beans' and then find that the 'beans' run out mid manoeuvre. Forewarned is definitely forearmed!!

Clive, I assume the significance of the Courier spring is a higher spring rate to cope with a commercial payload? If such a spring were to be used on a Mk1 would it potentially make the ride a bit harsh? Also, what is the availability of these Courier springs like? or are we talking modern repros?

Regards,

Ian 

 

Theres always a trade off with spring rates Ian. Certainly a lowering block would be a good start but also weight in the boot (not good for acceleration of course) and increasing rear wheel toe in can be beneficial....

[Clive]

The spring making company is Owen Springs. They have a great reputation.... and will make a spring to your specification. The trick is knowing what you want. They can decamber if required.

When I fitted my courier spring, with 1" lowering block, it sat silly high. Until I loaded the boot up with a load of stuff, bags or sand or suchlike, and had to negotiate a number of speed humps. That settled the spring, and then it sat at a sensible height, not silly low. And yes, a bit (lot) stiffer than standard, but not uncomfortable. 

I suppose the "best" solution is rotoflex/CV. After all that is what I am using on my spitfire. But a swingspring handles almost as well, especially if you don't carry rear seat passengers as the swing springs are a bit soft.  That is what I used on my 2.5 Vitesse convertible when I built it back in 1994 (I had several cars that donated parts, so chose swingspring over rotoflex, 2.5 over 2.0, mk1 chassis/V5 and so on. It was exactly what I wanted, and was my everyday car for 13 years. The herald came along approx 2000 as a workhorse, and used for lugging stuff around and autotesting etc being a more nimble car, and stayed until it was getting too frilly around the edges and then replaced by a Toledo in 2008)

[dave.vitesse]

The rear tuck-under is overstated as it all depends on how you drive the car. Most people back in the 1960's didn't have a problem once they knew how to drive the car, that is in the classic way. i.e. - As you go into a bend line the car up and slow down, then accelerate out of the bend. Most track and rally people used to fit a stronger spring with a slight negative camber. Others used the camber compensator. These do work well but hangs below the diff so reduces the ground clearance. They do still crop up now and again on ebay. The easy option is to fit a stronger spring, Courier van, and a small spacer between the spring and diff to give a negative camber. Also a weight in the back can help.

But as I say it all depends on how you drive the car. Under normal day to day driving there isn't a problem.

Dave

[johny]

I think the issue now is that with modern cars many people have grown to be quite accustomed to braking in bends if required and this presents no problems.  However when they change to driving some of our cars it comes as quite a shock that doing the same can bring serious consequences and of course, to be fair, sometimes the unexpected can happen mid bend and braking is unavoidable. I find the experience very similar to riding a motorbike which also cant be braked hard in bends so in both cases its even more important to adjust your speed beforehand and anticipate problems as early as possible....  

[JohnD]

Indeed it was down to the journalists' for setting up a perpetuating this canard.     They knew, for they were educated and knowledgeable about car engineering, and knew that tuck-in is a known deficiency of the swing-axle suspension.   So as soon as they were let loose on this new car, with its vaunted, fully  "independent suspension", they set out to see if they could get it to tuck-in.    And of course they did!   You will if you try hard enough!

Dammit, if you have deadline for your copy, you need something to write about!

The swing spring was as innovative and ingenious as the swing-axle was, in fact, as frankly old-fashioned, having invented in 1903!      Several other well known cars, Chevvy Corvair, VW Beetle and yes, the Mercedes 300SL (!) shared it, and share the Achilles heel.     Swing spring made a big difference, but other mods can get rid of any tuck-in, if you are willing to tolerate the loss of some advantages of the system.   As johnny says, a harder spring and a spring lowering spacer are very effective.

My needs are extreme, I race my Vitesse, but a VERY stiff spring, a high (1.5") lowering block and other (why should I tell you all my secrets!?) things completely abolish tuck-in.     But it can be a rough ride!

John

[Nigel Clark]

Hey John, please go easy on us journos... Some of us have loved our Triumphs for many years, including those blessed with swing spring IRS!

We even do our best to promote the Triumph marque when we can.

Nigel

[Pete Lewis]

 Nigel     remember doing this   at the Mosquito museum ??   no mention of tuck under  !!!

 

[Nigel Clark]

I remember that well Pete, happy days! Yours was/is the best sorted Vitesse 6 I ever saw.

Having just acquired a Spitfire Mk3, with swing axle rear suspension, I'm happy with how it handles. But it's never a good idea to arrive at a bend too fast then hit the brakes!

Nigel

[Pete Lewis]

yes brake before and power out 

  but  i learnt to drive in 1963,  

    still works for me 

Pete

[Nigel Clark]

Motorcycles from 1970 then cars a couple of years later taught me that battle first, slow in, fast out is the best way to make progress when the going gets twisty

Nigel

[rogerguzzi]

2 hours ago, Nigel Clark said:

Motorcycles from 1970 then cars a couple of years later taught me that battle first, slow in, fast out is the best way to make progress when the going gets twisty

Nigel

Hello All

              Plus read the bends(as the police used to teach)if it is still tightening wait and if looks to be opening open the throttle.

I to was more of a motorcyclist and it hurts if you fall off(I know several times!!!!!)

I lead a group of younger riders on a trip to mid wales when I had my Moto Guzzi 1100 sport(A beast that took no prisoners!) but when we got to the coast they all said what a great ride and we think your brake lights are faulty as they do not come on very often! 

I said just read the road it is not a race track were different criteria apply!

Roger

[Colin Lindsay]

Wheeler Dealers yesterday featured yet another American car (although it was a Honda Civic so technically Japanese) but Mike was learning how to drive with regards to fuel economy, part of which was not to brake for bends as the necessary acceleration afterwards uses a lot of fuel. Be at a speed that the car can cope with when cornering, don't brake, and by the end he managed about 57 mpg.