MK1 Handling
Posted By : George Ralph, 12-Dec-2006, 04:25pm
Don't you love the so called "experts", especially the ones who bang on about the MK1 back end. Especially those who have probably never driven a MK1.
Yes you could swap a complete MK2 Rotoflex rear end onto a MK1 but it's a lot of bother for not a lot of gain.
Just convert to swing spring using Spit 1500 or late MK3 parts (spring and a/r bar). You could fit the longer shafts as well or a lowering block under the spring (much easier). I would also upgrade to some 330lb springs on the front (plenty enough for the road) and some decent shocks. This lot has the advantage of looking pretty stock but giving a big improvement on handling.
I don't think you would notice the difference on the road between a standard MK2 and a MK1 modified in this way. This is pretty much how mine is modified except for the spring rates, poly bushes, AVO shocks and geometry and I have no handling issues. Many of the best handling racers use the swing spring set up and swear by it.
Stay away from "experts", or at least check their credentials!
Just convert to swing spring using Spit 1500 or late MK3 parts (spring and a/r bar). You could fit the longer shafts as well or a lowering block under the spring (much easier). I would also upgrade to some 330lb springs on the front (plenty enough for the road) and some decent shocks. This lot has the advantage of looking pretty stock but giving a big improvement on handling.
I don't think you would notice the difference on the road between a standard MK2 and a MK1 modified in this way. This is pretty much how mine is modified except for the spring rates, poly bushes, AVO shocks and geometry and I have no handling issues. Many of the best handling racers use the swing spring set up and swear by it.
Stay away from "experts", or at least check their credentials!
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MK1 Handling
Posted By : Piero Franchi, 12-Dec-2006, 07:38pm
Sorry
Cant agree!!!!!
The swing spring is a cheap and easy option. thats all.
for the effort thats involved in putting rotoflex over swing spring I would say go for swing spring.
BUT and its a big but. swing spring is NOT better. No were near better.
you have to look at the thing as a hole unit, not just a rear suspention upgrade.
The rotoflex gives added weight to the rear were it is needed.
the rotoflex gives a better footprint for the tyre.
the rotoflex takes out any drive train issues with half shaft brakege.
etc etc etc.
The swing spring you MAY have fitted is better than the normal Mk1 set up, thats why you are singing its prayzes (speeling mistake, sorry)
But it all depends what you want at the end of the day.
DONT right off the rotoflex, it is very good.
Not 2 b taken personaly. all the above is just my oppinion.
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MK1 Handling
Posted By : Mark Palmer, 12-Dec-2006, 08:18pm
Stephen,
IMHO, I'd say there isn't a massive difference between the two. I have a Mk1 an a Mk2, and there are pros and cons with both cost/ease of work etc). I personally think the rotoflx model isn't that hard to fit, once you've learned from your mistakes. But if you don't intend to race it don't change it, whichever set up you've got.
Cheers,
Mark.-
MK1 Handling
Posted By : Stephen Morris, 13-Dec-2006, 08:41am
thanks all,
looks like there are pro's and cons for both options!!
Are these both just a bolt on option?
Has anyone got any ideas if these jobs are written down/explained anywhere for reference?
Stephen-
MK1 Handling
Posted By : Chris Taylor, 13-Dec-2006, 11:04am
You have started a potentially unending debate here!
Triumph reverted the last Mk3 GT6's to swing spring from Rotoflex, and virtually no-one noticed!
Both CAN be bolted on, but really the swing spring is a much easier conversion to do, and easier and cheaper to get the bits. And the swing spring set-up is easier to work on if bushes or wheel bearings etc need replacement.
Ultimately the rotoflex is potentially a better set up, especially if you modify it with aluminium uprights, relocated wishbone pivots, and even CV jointed drive shafts. But for road use, I honestly think the swing spring is the most practical option.
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MK1 Handling
Posted By : Nigel Gibbins, 14-Jan-2007, 05:47pm
I can attempt to add fuel to this debate...
I can only say what I know and what I have seen with racecars... after all, it's all about the handling were talking and these cars demand the ulitmate in that.
I have seen rotoflex, swing spring, 'fixed' spring, sliding splines and various other modifications, additions and tricks to make the back handle and of all these the quickest top take a corner has always been swing spring and those who have tried 'fixed' and swing have said there's no difference once set up correctly. I found that hard to bellieve to be honest but there was no reason to lie about it.
Of course the best setup requires lowering of the rear to induce about 3-4 degrees negative camber and that may not be feasible on a road car.
Camber compensators have been tried and thrown away as have rear anti roll bars - so I would never bother with these myself. In fact I did fit a rear anti-rollbar at the beginning but removed it after a few races which resulted in a massive improvement in the cars cornering speeds.
The trick is to stiffen the front springs considerably and play with the rest until you like it... play with the toe setting (front and rear) and you will get there. As for front anti-roll bars... most racers run 1" dia ones, some run standard and I've even know some to run without an anti-rollbar a all! There is no disceranble corner speed differential between any of these cars but they will obviously all handle differently... which brings it down to a question of preference...
As has been said before - don't listen to experts - the best expert you know is yourself and handling as I have said can be a question of taste... if you like a loose car and it gives you condifence then you will corner quickly. If you like a tight car and it gives you confidence then you will also corner quickly...
I'm no help really am I?
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MK1 Handling
Posted By : Chris Taylor, 14-Jan-2007, 07:32pm
A swing spring car with no front anti-roll bar sounds a strange beast, unless the front springs are just about solid! Standard springs at the front, no anti-roll bar and a swing spring at the rear would roll like a jelly with almost no roll stiffness!
Interesting that some claim the Courier Van one of the best handling Heralds with no front anti-roll bar and a stiff rear leaf spring; almost the exact opposite of a swing spring spitfire!
As you say, it's a matter of what suits you!-
MK1 Handling
Posted By : Nigel Gibbins, 15-Jan-2007, 08:59am
I agree - a strange beast indeed - but it worked. Not my car so I can't say how it felt.
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MK1 Handling
Posted By : George Ralph, 13-Dec-2006, 08:39am
Piero,
Re read my thread. I never said swing spring was better, I was just answering the question within the context of the original thread. And I didn't write off the Rotoflex, far from it. I just advised that for a road going MK1, driven normally, the swing spring conversion is an easy upgrade that would give an effective improvement on a par with the standard rotoflex setup, whilst maintaining an original look.
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MK1 Handling
Posted By : Stephen Morris, 13-Dec-2006, 01:18pm
ah that's clearer (i think!)
to summarise as I don't want to start an unending thread
As my car is going to be used on the road I would just like to tweak things at the rear a little so that they are a better than standard so the swing spring option looks to be simplest and worth trying first in conjunction with lowering the rear, adjustable shocks poly. bushes and possibly a rear anti roll bar (I will of course give the same level of attention to the front end), if I then want to go further the rotoflex option could be fitted at a later date.
So what would be the best donor car for a bolt on swing spring conversion and is it just a case of unbolting the old and bolting on the new?
I'd like to do the work myself and can do most things (except weld) so I'm hoping a suitable car can be canabalised or the parts bought new/recon from Rimmers etc.?
Stephen
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MK1 Handling
Posted By : Charles Bushell, 13-Dec-2006, 08:23pm
Canleys do a complete kit for a reasonable price: http://www.canleyclassics.com/featuredproducts.asp...
I think it's a late GT6III spec spring & front anti-roll bar.
Charlie -
MK1 Handling
Posted By : George Ralph, 13-Dec-2006, 08:39pm
You need the spring and spring box assy from a 1500 Spit or late GT6 and the 7/8 in a/r bar and clamps from the same car, phone around, you should find them easy enough. You would probably best to change the spring for a new one. Replace your old spring with the new one and box. You will only need 4 studs to fit the new spring and box, if you use a lowering block (Canley, Jigsaw etc) then 4 longer studs or bolts should be supplied. If you fit uprated shocks, use the ones with an adjustable spring seat, this way you will be able to get the front ride height spot on regardless of the type of coil spring fitted. As I say, I would use 330lb front springs for the road (standard are 220lb). I have 480lb springs 'cos I do some motorsport. I used 330lb before just for the road and they were just right in my opinion. I have my 330lb Triumphtune springs spare now if you are interested (done about 3000miles).
This is a really easy upgrade, straight replacement and no special tools required. You will need a spring compressor to dismantle the front shocks just to get the top mounting plates off. If you use adjustable spring seat shocks then you won't need the spring compressor for reassembly.
The hardest part is changing the bushes, the b*ggers normally don't want to shift after 40 years! A vice and a couple of sockets does the job though. Refitting poly bushes couldn't be easier (see instructions on Canley website, good place to buy them too). Make sure you buy the "touring" grade of bushes if you want to keep your fillings.
Whilst you at it, be sure to change the radius arm bushes for poly or new rubber. The old ones (particularly the big one) turn to sponge over the years and do nothing for axle location!
Really should only be a weekend job. Or you could split into three jobs to spread the budget: (1) Swing spring and a/r bar for an immediate improvement; (2) Poly bushes all round; (3) Coil springs and shocks (shock ain't cheap).
Hope this helps... -
MK1 Handling
Posted By : Chris Taylor, 14-Dec-2006, 10:22am
I would advise AGAINST a rear anti-roll bar. The swing spring works by reducing the rear roll resistance so that the car cannot jack up around the outside wheel. To stop the car becoming a complete jelly, the front anti-roll bar is thicker to compensate. Adding a REAR bar is likely to interfere with the working of the swing spring.
I'd also have a look at the car and try it out after the swing spring has settled into use before fitting a spacer block. The GT6 does not have a huge suspension travel as it is. A spacer block lowering the rear end helps the handling of a standard swing axle car by putting the rear wheels into permanent negative camber. This increases grip and also helps to reduce tuckunder as the car has to "climb" a lot further round the outside wheel. This should not be necessary with a swing spring, especially if it is a secondhand one with a bit of settling in use. If you feel you do still want to lower the rear end, it wouldn't be too difficult to insert one later on.
Try the standard GT6 swing spring set up first. Replacing the bushes and shockers will be a good idea and probably well overdue. I think you will be pleasantly surprised with the results!-
MK1 Handling
Posted By : John Davies, 14-Dec-2006, 11:16am
I agree with Chris.
I spent ages calculating spring rates and torsion bar thicknesses, to fit an ARB to the Silverback.
Pproper spherical joints and all.
At Oulton this year, for other reasons, I removed the bar between practice and race.
Result? B*gg*r all.
Either my calcs were nonsense (quite possible) and I made too weak a bar, or the influence is minimal.
The Sb has a swing spring, and a 1" spacer, just as Chris and others suggest.
John-
MK1 Handling
Posted By : George Ralph, 14-Dec-2006, 12:46pm
I too spent ages making a rear a/r kit and ended up chucking it. Know descernible benefit and probable opposite effect. I have a 1in spacer, but I am using short driveshafts. The camber on my rear wheels is spot on. Chris is right, I suspect with some springs, long shafts and a spacer, the camber could end up being excessive.
It's always best to make changes one at a time and evaluate.
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MK1 Handling
Posted By : George Ralph, 14-Jan-2007, 10:18am
Just to continue the Swing spring v rotoflex debate: I received a DVD of my first attempts at hill climbing for Xmas. Since it was my first time, the
attempt is, at best, unremarkable, but for the behaviour of my rear suspension in the hairpin. I have a swingspring conversion and one inch block
fitted with standard length shafts. As can be seen in the footage, the rear wheels don't tuck under, nor is there "snap oversteer". The inside wheel
does unload, but that is more due to the 330lb front springs (now uprated to 480lbs).
The footage is on YouTube as I don't know any other way of sharing it. The overall time, by the way, is very slow and I hope to improve on that with practice (Oddly the results show it as quicker than the bloke in the Ferrari Dino on the prevous day!).
http://www.youtube.com/watch?v=KUgkCRgpDpE
The footage is on YouTube as I don't know any other way of sharing it. The overall time, by the way, is very slow and I hope to improve on that with practice (Oddly the results show it as quicker than the bloke in the Ferrari Dino on the prevous day!).
http://www.youtube.com/watch?v=KUgkCRgpDpE
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MK1 Handling
Posted By : Chris Taylor, 14-Jan-2007, 11:34am
It ain't pretty, you may not consider it clever, but it DOES work doesn't it?
Actually, I think it IS rather clever. A lot neater than the compensating springs etc used by Porsche and Mercedes, but only possible with a leaf spring. And there are some regrettable aspects of the rotoflex set up as well. (Cost, weight, more difficult to work on, and even the geometry can be improved on).
It is now a more than closed book, but I can't help but think how many more GT6s and Vitesses would have been sold if the swing spring had been introduced rather earlier - it had been "invented" in 1959. Although costed at only &163;1 more per car on the Herald, there was such a fight to keep costs down (look at the competition from Mini and Anglia that year) one can see why it was left on the shelf. But the argument for more upmarket (and much quicker) cars like Vitesse and GT6 seems rather different in hindsight.
Another option might have been to market it as a tuning accessory, like uprated engines, or even an extra cost option like overdrive, brake servo etc. Perhaps having been put back on the shelf in 1959, it was forgotten about for some years!
Like the noise your car makes; reminds me of an Aston DB4/5. Shades of Bond in "Goldfinger" in the Alps! -
MK1 Handling
Posted By : James Fotheringham, 15-Jan-2007, 01:25pm
George,
your GT6 sounds like the Dogs danglies - simply awesome!
Thanks for the post on the relative merits of suspension bits, you have helped me make my mind up on mine!
PS. If you are going to be doing a lot more hill climbing, the I would recommend a 4.11 diff, as the std 3.27 gt6 diff is far to high!
I believe there is even a 4.55 from Courier vans if you look hard enough!
However it does comprimise road performance!-
MK1 Handling
Posted By : Colin Wake, 15-Jan-2007, 01:47pm
You don't have to look too hard for the CW&P's for 4.55:1.
I beleive Canley Classics use them as door stops they have so many!
Same as MArina van also???
Cheers
Colin -
MK1 Handling
Posted By : George Ralph, 15-Jan-2007, 02:20pm
James,
Thanks for the kind comments. I was also pleasantly suprised by the great sound of my car from the outside (almost as good as inside!). People have told me it sounds great but obviously I don't get to hear it. I particularly like popping on the over run (like a grown up race car) though I guess one of the gurus will tell me that it shouldn't happen I guess.
I have a 3.89 diff with o/d at the moment. The o/d might be usefull on longer climbs or sprints for grabbing o/d third (effectively 4th) with a clutchless change. She pulls well at the moment so I will stick with that gearing for the time being.
As a point of fact she was pulling well at Longleat, then I discovered afterwards that the throttle pedal stop (cable throttle) had slipped and I was only getting three quarter throttle! Can't wait to get out there on full throttle!-
MK1 Handling
Posted By : James Fotheringham, 15-Jan-2007, 04:43pm
Can't argue with that George. Hell you proably have so much Torque you could stick it in 4th and not change once!
Cheers for the heads up Colin, I didn't realise they were so common!
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MK1 Handling
Posted By : David Rumens, 14-Jan-2007, 12:37pm
From my own experience fitting a Camber Compensator to a Mk1 Vitesse gave very near Rotoflex results. The only problem is the mounting frame hangs
below the diff and will reduce the ground clearance. But the Camper Compensator is easier to fit than the Swing Spring. However the Swing Spring was
original equipment on the Mk111. It's your choice.
One thing is for sure you can improve the swing axle roadholding without the costly approach of modifying to Rotoflex.
Just a note on the Vitesse - The swing spring mod can reduce the weight carrying capacity of the car. Where as the Camber Compensator will not.
Just my experience.
One thing is for sure you can improve the swing axle roadholding without the costly approach of modifying to Rotoflex.
Just a note on the Vitesse - The swing spring mod can reduce the weight carrying capacity of the car. Where as the Camber Compensator will not.
Just my experience.
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MK1 Handling
Posted By : Van Hamlin, 14-Jan-2007, 04:12pm
"Camper Compensator" - now that's a good idea David.
Is it a device to allow you to drive at normal speed and not get held up by queues of holidaymakers?
Or is it a device to make you appear more masculine if you feel that you're not?
Camper compensators and swinging axles - all persuasions were catered for in the 60's !!!
Van
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MK1 Handling
Posted By : Barry Huffer, 15-Jan-2007, 01:04pm
Nothing to do with the relative merits of different configurations, all far too far over my head, but a tip for bush replacement.
Get a drill slightly over the size of the metal centre and start to drill it out. In very short time the heat from the drilling releases the metal core and it comes out leaving the easy job of removing the rubber bush.
Its a little smelly and the bush can get messy but it works and is relatively quick and easy. I cannot claim credit for this as it was Mark at Jigsaw that told me when I replaced my bushes.-
MK1 Handling
Posted By : Steve Smith, 15-Jan-2007, 01:19pm
As a point of reference, several years ago I posted a verbatim copy of the US Competitions Department Factory bulletin regarding the swing spring conversion. It can be found here: http://gt6.com/triumph/issue3/article.asp
Steve
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MK1 Handling
Posted By : John Martin, 15-Jan-2007, 06:50pm
Speaking purely from my experience with my Mk1, I would say the following:
I uprated the front suspension to 1" lower than standard 440lb springs and new Koni shocks, and fitted new Koni shocks on the rear, and 175/70 wet weather tyres all round. As yet I have not fitted a lowering block, but am considering a half inch one to induce a little more negative camber at the back.
What I have done to date, though, has totally transformed the handling of the car. It now takes corners with confidence. I can rag it round my favourite 'test track' with ease now, Birling Gap road. See my profile for more info.
As other people have said, it is purely a personal preference what suspension to fit. Having driven my car for almost 4 years now, I have come to like the way my car handles. I know its foibles, and compensate accordingly. For road use, the Mk1s suspension is, in my view, perfectly good. You just have to treat it with a bit of respect.
I uprated the front suspension to 1" lower than standard 440lb springs and new Koni shocks, and fitted new Koni shocks on the rear, and 175/70 wet weather tyres all round. As yet I have not fitted a lowering block, but am considering a half inch one to induce a little more negative camber at the back.
What I have done to date, though, has totally transformed the handling of the car. It now takes corners with confidence. I can rag it round my favourite 'test track' with ease now, Birling Gap road. See my profile for more info.
As other people have said, it is purely a personal preference what suspension to fit. Having driven my car for almost 4 years now, I have come to like the way my car handles. I know its foibles, and compensate accordingly. For road use, the Mk1s suspension is, in my view, perfectly good. You just have to treat it with a bit of respect.