I knew i could get the tuscan to handle.......

[spitfire4v8]

Basil Brush said:

basil brush said:



Do you mean changing the alignment, firming up the springs or actually moving the rack to level out the track rods?



I never did get an answer to this in May 2003.....

(Sorry, I really must get out more. Oh hang on, I can't...)

I've tried all sorts over the years, some things less successful than others. I now say put it back to standard, then get it properly set up, then re-assess if there is anything you want to improve.
Not everyone complains about the handling of these cars, so they are not all bad .. I suspect much is down to lacklustre servicing (geo is supposed to be checked on every service .. but how many service centres actually do it?). As the front springs naturally sag and toe changes I'd bet this is responsible for more handling issues than anything truly fundamentally wrong ..

as i say, my own very early tuscan is as TVR sent it out, runs soft springs for a nice ride, and I have no issues travelling down bumpy roads in it.

[DuncanM]

I thought standard would mean shocks/springs too, my mistake.

Damper settings can drastically change the behaviour of a car, once people have adjustable dampers on, the car could be awful or great depending on just the dampers, even I if the geometry is sound.

Also, personal preference comes into play of course.

[m3jappa]

DuncanM said:

Your car looks incredible! If this came out today it would look bang up to date, especially in the colour and wheels you have, great taste

Do you mind advising on your damper settings front and rear?

Thanks duncan

I have them set fairly soft. iirc 5 clicks front 5 clicks rear towards the soft side.

Bare in mind these are the mono shocks so much much better (imo) than the normal golds. Very compliant ride.

[m3jappa]

It seems this is a very complicated subject, with some saying they are terrible and some saying not that bad. It is subjective and depends how you drive them, i really believe that.

When i got my car it was lethal, i will never forget flooring it, being dragged across the road (and the dash flying off)

I am very very fussy with handling and 'feel' .
i have previously had an evo 9 and a stripped out m3 with bilsteins which was set up by geoff steel racing (btc team). As you can imagine they both handled well!

I am mechanically very sympathetic, always warm up etc but i do use the car, i think many years ago i took a member from here out on track and he said he had never been in a tvr driven like it so i do use it!

I knew i could make the tuscan what i wanted, infact in my early days of ownership (read that as gaz mono, decent geo, lighter wheels) it was actually quite good. my issue wasn't so much bump steer it was the rear end, it felt detached and unpredictable. It would catch you out! the front was quite good tbh.

I have now put that down to tyres (i always used a track biased tyre) and possibly worn bushes at the rear.

Now i have done all this work i cant assure you enough just how well this car handles, id love someone else to drive it (properly) it is no longer an oversteer monster i am nervous about, it doesnt pull all over the road, its actually very stable, it does still have some bump steer but then i have never driven a car down a b road that doesnt have some. even the porsche cayenne i have has a bit!
i even let a scooby owning mate drive it as im that confident in it, i wouldn't have done that before. He loved it

i have heard later cars are just as bad, again subjective, if your doing 50 down a b road its totally different to 90...... (kph of course).

remember as well most people are raising their rack up, like i used to which was 10mm now those spacers have come out and my arms sit totally parallel. There is no noticeable issue at all. the only reason the rack is raised (from factory as well) is to try and level the arms up afaik.

Im just a normal bloke with no engineering experience but can drive a car. I think the whole package of whats been done is why its now good. And of course having it set up by centre gravity is as or more important. best geo i have ever had done on any car!

[m3jappa]

spitfire4v8 said:

What you want to avoid is this fail of a bumpsteer mod which was marketed some years ago ...

what was this mod? and also how have you loaded it up like that to take pics? i can try and do the same if possible to see what mine looks like.

[m4tti]

It would be good to get somewhere to measure and compare a standard car, with a car with the sagaris arms, and put this to bed.

Str8six used to do the steering arm mod until the arms ran out..

I’ve spoken to someone in the past who raced a T350 with the str8six arm mod, and it apparently was a significant improvement.

[dvs_dave]

Couple of short YouTube vids here of someone testing the factory setup for bumpsteer on an early 2000 Tuscan, and then with the rack spaced up 4mm.

Bloke called mpett, who was a regular poster here during his rebuild, but not sure if he’s still around?

https://youtu.be/3QKvdZWyV_I

https://youtu.be/_Yt0JcNhxOA

I’m not completely sure what conclusions can be drawn from this, but the poster says there’s “oversteer“ in both scenarios, but that doesn’t really make any sense when talking bumpsteer. Unless he’s confused excess toe-in on compression as possibly causing vehicle oversteer? Hard to say, but the amount of bumpsteer is seemingly reduced by the rack spacers.

[spitfire4v8]

m3jappa said:

what was this mod? and also how have you loaded it up like that to take pics? i can try and do the same if possible to see what mine looks like.

It was something sold maybe 10 years ago ..

the way I did the pictures was that the car had no spring/damper unit on so I could use the 2 post lift to raise/lower the car through the full range of what would be the damper unit if it were fitted ie full droop to full compression.
If you put the tyres on some skid plates and have a simple 2 wheel aligner you can quickly take toe measurements through the full range. This kit had something like 8 degrees total toe change ..

[anonymous-user]

m4tti said:

It would be good to get somewhere to measure and compare a standard car, with a car with the sagaris arms, and put this to bed.

Str8six used to do the steering arm mod until the arms ran out..

I’ve spoken to someone in the past who raced a T350 with the str8six arm mod, and it apparently was a significant improvement.

I'm sure HHC (Hexham) have some modified arms for sale. Worth a call if you're after some.

Tony 01434 601666

[m4tti]

spitfire4v8 said:

It was something sold maybe 10 years ago ..

the way I did the pictures was that the car had no spring/damper unit on so I could use the 2 post lift to raise/lower the car through the full range of what would be the damper unit if it were fitted ie full droop to full compression.
If you put the tyres on some skid plates and have a simple 2 wheel aligner you can quickly take toe measurements through the full range. This kit had something like 8 degrees total toe change ..

What was that kit though. Was it the rose joint based thing.

[spitfire4v8]

yes it had a machined adaptor and a rose joint .. was developed by a land rover suspension engineer ? 8 degrees of toe change on a land rover might be considered an improvement I don't know.

[m4tti]

I definitely wouldn’t compare that heath Robinson concept to the sagaris arms.

[Basil Brush]

Could someone with the sag arms measure what the effective tre pivot height change is compared to the straight arms?

I've got my bump measurements somewhere from when I was comparing original '00 to '02 on Tuscan setup and working out the rack spacing. The trace for the early setup is a curve so it's possible to get either initial bump toe out or bump toe in depending what your ride height is set at. I think this is why the early cars are so sensitive to set up and limiting wheel travel helps.

[dvs_dave]

dvs_dave said:

Couple of short YouTube vids here of someone testing the factory setup for bumpsteer on an early 2000 Tuscan, and then with the rack spaced up 4mm.

Bloke called mpett, who was a regular poster here during his rebuild, but not sure if he’s still around?

https://youtu.be/3QKvdZWyV_I

https://youtu.be/_Yt0JcNhxOA

I’m not completely sure what conclusions can be drawn from this, but the poster says there’s “oversteer“ in both scenarios, but that doesn’t really make any sense when talking bumpsteer. Unless he’s confused excess toe-in on compression as possibly causing vehicle oversteer? Hard to say, but the amount of bumpsteer is seemingly reduced by the rack spacers.

I found the thread that gives context to these vids. Good thread with lots of info and reminders.
https://www.pistonheads.com/gassing/topic.asp?h=0&...

[TV8]

Never driven a Tuscan but have driven properly set up cars and the difference between before and after the set up is very noticeable. Factor in some new components vs 15-20 years old stuff and all should be fine.

Over in 911 land where I now find myself, lots of different set ups and manufacturers taking lots of money from people and a variety of opinions on what’s best! A group of owners organised a test day for everyone to drive each other’s car. I think centre of gravity were involved as well and they sort of reached a consensus on what was best. It worked out expensive for the main organiser as I think he changed a few things afterwards!

[spitfire4v8]

And the important thing is always to measure what you have to begin with and note what the differences are geometrically and in feel when you make any geometry changes or hardware changes.

You wouldn't embark on an engine tuning programme without testing the engine to begin with, same with suspension.

[spitfire4v8]

dvs_dave said:

I found the thread that gives context to these vids. Good thread with lots of info and reminders.
https://www.pistonheads.com/gassing/topic.asp?h=0&...

Interesting that we are still discussing the exact same things 8 years on. You'd have though we would have had this licked by now ..

[m4tti]

Just to add to this a previous thread from a respected TVR aficionado..

[mk1fan]

Are you saying that was a worthwhile mod?

[jmd68]

Hi all, I have a Sept 2001 Tuscan S with Gaz Pro shocks, and am really happy: stable even on bumps, great turn-in, very predictable.
The car is sitting pretty high (39 cm between wheel center and wheel arch both front and rear), with max caster and otherwise standard setup with 255/35/18 all around.
The biggest improvement I experienced was moving from GoodYear Eagle F1 Asymmetric(1)s to GoodYear Eagles F1 Asymmetric 5s.
With the former, I was experiencing extreme tramlining, even at 20/23PSI F/R. With the new ones, no tramlining even at 23/26PSI. Turn-in is a bit slower, but still quicker than any other car I have ever driven. (As a side note, I am running GoodYear Eagles F1 Asymmetric 5s on my Cupra Ateca daily driver, but in the more rigid SuperSport version to get acceptable steering feel - I suspect those would make the Tuscan tramline again).

Now to my only concern: The turning circle is so high that I struggle to maintain any kind of drift on track. If I don't catch a starting drift quickly, it quickly gets past the angle that can be recovered with the steering on full lock. I read that the Sagaris upper wishbones create more space for wheel angle. Does anyone know if I could use those? What about the steering rack, should I swap it for a Sagaris one, or could I adapt it to increase its reach?

Thx!

JM

Edited by jmd68 on Wednesday 19th January 14:43