Up-rated Anti-roll bars anyone??

[motul1974]

Has anyone tried up-rating the standard anti-roll bars? All this discussion on the Mk2 Tuscon suspension has made me wonder. Given their more road orientated set up, would having stiffer bars improve their, or any other softer suspension, on track ability?

[QBee]

I seem to remember Phazed sourcing some stiffer ARBs last year for his 370 bhp track monster.

[ClassicChimaera]

A thicker ARB will help but if it's got soft springs,,, on track your putting so much force through the shocks and the ARB will not cope with that any better.
Spring rate is the only answer to huge weight changes when forcing a Car on track.
IMHO

[portzi]

QBee said:

I seem to remember Phazed sourcing some stiffer ARBs last year for his 370 bhp track monster.

I have to agree with you on this one Anthony, " Phazed is definitely hiding a monster under his bonnet"

[phazed]

Standard I believe are 18mm and 22mm.

I sourced an uprated pair on pistonheads classified and now have 22mm and 25mm fitted.

Do they make a difference? Hard to tell but as part of the whole package of my upgraded suspension, the whole lot work extremely well and the car handles brilliantly imho.

[QBee]

ClassicChimaera said:

A thicker ARB will help but if it's got soft springs,,, on track your putting so much force through the shocks and the ARB will not cope with that any better.
Spring rate is the only answer to huge weight changes when forcing a Car on track.
IMHO

I seem to remember the 1964 Tokyo Olympics with startling clarity, but am a bit vague about more recent things.

But I think I remember Mat Smith saying he ran 800 lb springs on his championship winning race Chimaera. I certainly remember him driving my car at Donington and being shocked at how soft the rear suspension was. I had my coilovers set fairly soft that day, but am running 375 lb springs as well.. So having stiff enough springs to cope with both road and track, and good adjustable dampers, are a major part of the package.

[motul1974]

Its just I've been speaking Ben who supplies the Mk2 Tuscon suspension, and he's been telling me for my road and limited track use the 'standard' Tuscan S set up is ideal, but being as them run softish springs I just wondered would up-rating the anti-roll give me the best of both??....within reason of course.

[ClassicChimaera]

It can't do any harm and a thicker bar will defo offer resistance to body roll.

I've got a Chin on soft springs, even on Toyo T1R tyre's and a standard ARB It's easy to fully load up the springs and then your done. The car will not go any faster when it's bottomed out. The weight transfer is so great when corner forces are applied if the springs can't hold the car up the ARB has no chance.
Bens Shocks have updated springs so with that and big ARB's it might be just right

Here my car almost exactly a year ago at a cold and vaguely damp Blyton Park, ( tight little place ) but with 350/275 springs
Easy to find there limits and this is with fully hard dampers too.

[sparkythecat]

There was some debate on the pros and cons of fitting uprated ARBs on the droplinks thread a few weeks ago http://www.pistonheads.com/gassing/topic.asp?h=0&a...

[ClassicChimaera]

QBee said:

I seem to remember the 1964 Tokyo Olympics with startling clarity, but am a bit vague about more recent things.

But I think I remember Mat Smith saying he ran 800 lb springs on his championship winning race Chimaera. I certainly remember him driving my car at Donington and being shocked at how soft the rear suspension was. I had my coilovers set fairly soft that day, but am running 375 lb springs as well.. So having stiff enough springs to cope with both road and track, and good adjustable dampers, are a major part of the package.

800..... he's a boy
For racing only !

Just shows you the forces involved.

I've often noticed the Mazda race cars set with stiff springs but soft ARB settings

For our softer road cars the ARB probably has more importance and combined with good spring rates keeps the car feeling tight yet allows some movement for the slower corner forces.

I removed the rear ARB and it's what the Americans would describe as ( loose) good for slow local stuff but loose at speed,,
If that makes sense.,,,,, saying that I hardly notice the difference at road type speeds.

[griffdude]

ClassicChimaera said:

I've often noticed the Mazda race cars set with stiff springs but soft ARB settings

Interesting discussion....

Precat Griffs didn't have a rear anti-roll bar as standard.

My Griff has slightly uprated springs 425/375 & no anti roll bar at the rear, rides & handles really really well.

My MX5 trackday car has significantly uprated springs but std roll bars, rides & handles really really well.

For twisty circuits in the TVR Speed championships, I know that the guys who do well often completely disconnect the rear ARB to aid grip out of tight corners. Then do them up again for the drive home..... I'm pretty sure all are running non std springs tho.

So, there you have it: Absolutely no help what so ever! Do what feels best.

[ClassicChimaera]

I think in many ways it's a way to help keep the cars attitude stable but still have relatively soft springs on as in road car!
The stiffer the springs the less they do and hence the less you need them.

[Engineer1949]

we had 500lb on the front and 400lb on the rear on nitrons they are now changed to the original weight springs was very planted on track not to much roll but when you consider the little ginetta has 800lb on the front and 550 on the rear and only weighs 850 kilos and the springs on the cerb i am building has 1100lbs on the front puts it into perspective


john

[Discopotatoes]

Engineer1949 said:

we had 500lb on the front and 400lb on the rear on nitrons they are now changed to the original weight springs was very planted on track not to much roll but when you consider the little ginetta has 800lb on the front and 550 on the rear and only weighs 850 kilos and the springs on the cerb i am building has 1100lbs on the front puts it into perspective


john

Just not much fun driving it to and from the track

[ClassicChimaera]

Engineer1949 said:

we had 500lb on the front and 400lb on the rear on nitrons they are now changed to the original weight springs was very planted on track not to much roll but when you consider the little ginetta has 800lb on the front and 550 on the rear and only weighs 850 kilos and the springs on the cerb i am building has 1100lbs on the front puts it into perspective


john

That Ginetta is going to be awesome.
At the end of the day it's about creating a big cart, keep everything taught and you have have a chance to control the car when side forces are trying to upset the balance etc. Controlling body roll and keeping the car neutral allows you to drive it faster. The less it rolls the less the weight pendulum swings,, in theory you can go faster and put that extra weight into the tyre with aggressive driving and actually get more grip and speed. Soft settings sap energy away,, it's better to scrub speed a bit with provoked under /oversteer as you enter the turning point so you've still got a fast car on exit. It's all track specific though, you might have hairpins and no fast stuff so bound to soften the car to get it through.

It's a great science and one minute it's one thing then a change in weather and your doing other things.

Tyre's as usual are the deciding factor based on their grip. If they are a racing slick so huge grip,,, big big springs to match etc etc.

Hope you win John

[jesfirth]

[quote=griffdude

My Griff has slightly uprated springs 425/375 & no anti roll bar at the rear, rides & handles really really well.

For twisty circuits in the TVR Speed championships, I know that the guys who do well often completely disconnect the rear ARB to aid grip out of tight corners. Then do them up again for the drive home..... I'm pretty sure all are running non std springs tho.


[/quote]

my griff has a similar set up similar to Howards. I have a stiffer front arb 28mm (I think from memory) and no rear arb - I took it off but I have stiffer springs on the nitrons to compensate. 750 front and 500 rear. its a a bit crashy on the road but great on track. one thing about a stiffer fornt arb is that it seems to create more slow speed understeer on turn in - so I end up taking a click or two off the front dampers to compensate. all in all it works well.

[Discopotatoes]

jesfirth said:

[quote=griffdude

My Griff has slightly uprated springs 425/375 & no anti roll bar at the rear, rides & handles really really well.

For twisty circuits in the TVR Speed championships, I know that the guys who do well often completely disconnect the rear ARB to aid grip out of tight corners. Then do them up again for the drive home..... I'm pretty sure all are running non std springs tho.

my griff has a similar set up similar to Howards. I have a stiffer front arb 28mm (I think from memory) and no rear arb - I took it off but I have stiffer springs on the nitrons to compensate. 750 front and 500 rear. its a a bit crashy on the road but great on track. one thing about a stiffer fornt arb is that it seems to create more slow speed understeer on turn in - so I end up taking a click or two off the front dampers to compensate. all in all it works well.

Where can you get these thicker anti roll bars?

[motul1974]

TVR Part Ltd do a 25mm frt and 22mm Rr, not cheap mind, but was wondering could we potentially get a less compromised car when using for road and a degree of track fun. I appreciate there's like to be so many variables dampeners, spring rates, preferences etc, just wondered about its ability to optimise our cars for what can be two extremes of driving.