Suspension testing
Discussion
Hi All
There has been much debate over the last few months about whether to go for standard sports shocks like Avo,Gaz,Spax,Koni etc, or whether Nitron/Ohlins or similar de-carbon gas shocks are worth the money.
I'm going to put this to the test and have found an impartial TVR owner with original Bilstein shocks fitted, who has agreed to start off with a new set of twin tube sports shocks and after an agreed period, change them over to a monotube gas shock.(probably Ohlins)
Warren at Topcats is setting up the car and will doubtless give us the professional viewpoint but more importantly, the car will be driven by the owner on a daily basis in all conditions, thus giving us decent data to assess.
There has been much debate over the last few months about whether to go for standard sports shocks like Avo,Gaz,Spax,Koni etc, or whether Nitron/Ohlins or similar de-carbon gas shocks are worth the money.
I'm going to put this to the test and have found an impartial TVR owner with original Bilstein shocks fitted, who has agreed to start off with a new set of twin tube sports shocks and after an agreed period, change them over to a monotube gas shock.(probably Ohlins)
Warren at Topcats is setting up the car and will doubtless give us the professional viewpoint but more importantly, the car will be driven by the owner on a daily basis in all conditions, thus giving us decent data to assess.
This aint scientific though... ok you get feedback from the owner, but not good enough IMO...
What you need is someone who is a known track enthusiast who posts some seriously good lap times, then you need someone who KNOWS the ohlins inside out and can set them up just right, same goes for the budget performer shocks...
Hire a racing telemtry kit, and then get back all the numbers, body-roll, G's, lateral acceleration etc etc etc... compute a scattergraph for each reading and draw through a mean output line...
Well, thats how its done by the pro's, so bugsy stop playing silly fannies, and put your rocket scientist helmet on...
What you need is someone who is a known track enthusiast who posts some seriously good lap times, then you need someone who KNOWS the ohlins inside out and can set them up just right, same goes for the budget performer shocks...
Hire a racing telemtry kit, and then get back all the numbers, body-roll, G's, lateral acceleration etc etc etc... compute a scattergraph for each reading and draw through a mean output line...
Well, thats how its done by the pro's, so bugsy stop playing silly fannies, and put your rocket scientist helmet on...
Thats the problem isn't it, we have immediate responses from the people who are interested in track type cars and know heaps about getting cars set up.
This accounts for about 10%, or less of the people driving the cars every day for work or fun but peer pressure tells them that if you haven't got Nitron/Ohlins you are somehow missing out.
Lets find out what the average Joe thinks of the differences, I should say that the person conducting this experement is high profile and will doubtless drive the car with a bit of spirit.
This accounts for about 10%, or less of the people driving the cars every day for work or fun but peer pressure tells them that if you haven't got Nitron/Ohlins you are somehow missing out.
Lets find out what the average Joe thinks of the differences, I should say that the person conducting this experement is high profile and will doubtless drive the car with a bit of spirit.
I'm very inetersted in the results too.
A lot of my development is done by an army of willing and able fast drivers who give me good feedback.
The development process must involve an element of *joe public* as you put it, cos as you say they're accounting for most of your market.
The vast majority of my damper testing for tracks is all about feel though .. you can't time on track days, and data loggers are also frowned on as often they contain timing equipment too .. on track days it's also much more about having fun than outright speed, though of course if you have a well set up car that inspires confidence the speed comes with it. Well set up cars are also kinder to tyres, brakes and generate good grip over a hard-worked track session.
For road driving it's much more about generating good feedback, that fun level again, also suppleness and safety under avoidance situations. I have a favourite test route that I know very well and I use it all the time to assess grip over changing surfaces .. it's all subjective but I can tell if a car is underperforming compared to what I know it's capable of in similar conditions. Get's a bit less consistent towards winter though as surface temps drop and grip drops off substantially compared to summer even on road tyres. you need to get your testing done pdq to avoid this situation as temps are dropping already.
It might be usefull for you to produce a tick-box list of feedback items you wish to monitor bugsy, as well as columns for making notes. I usualy test for over a month to make sure of the feedback I'm getting, then compare the notes from all the willing victims, erm i mean volunteers to make sure there's trends to the systems that i can then work on.
good luck
A lot of my development is done by an army of willing and able fast drivers who give me good feedback.
The development process must involve an element of *joe public* as you put it, cos as you say they're accounting for most of your market.
The vast majority of my damper testing for tracks is all about feel though .. you can't time on track days, and data loggers are also frowned on as often they contain timing equipment too .. on track days it's also much more about having fun than outright speed, though of course if you have a well set up car that inspires confidence the speed comes with it. Well set up cars are also kinder to tyres, brakes and generate good grip over a hard-worked track session.
For road driving it's much more about generating good feedback, that fun level again, also suppleness and safety under avoidance situations. I have a favourite test route that I know very well and I use it all the time to assess grip over changing surfaces .. it's all subjective but I can tell if a car is underperforming compared to what I know it's capable of in similar conditions. Get's a bit less consistent towards winter though as surface temps drop and grip drops off substantially compared to summer even on road tyres. you need to get your testing done pdq to avoid this situation as temps are dropping already.
It might be usefull for you to produce a tick-box list of feedback items you wish to monitor bugsy, as well as columns for making notes. I usualy test for over a month to make sure of the feedback I'm getting, then compare the notes from all the willing victims, erm i mean volunteers to make sure there's trends to the systems that i can then work on.
good luck
A measured response Joo, I don't know what will happen here but if Warren and the customer agree that monotube gas shocks are markedly better with enough plus points to justify the extra costs, then so be it but nobody has posted on trying sports shocks and then changing them for say, Nitron because they were so disapointed, lets find out.
True, but I know of people who have gone from std to avo to nitron .. the jump from std to properly set up avos was so great that they decided on going the next step too .. I offer a part exchange on that route so the customer doesn't lose out.
You don't have to be upset with the entry level dampers to move further up the scale, they might be so good compared to std that you feel the expense of better tailored pckages justified.
You don't have to be upset with the entry level dampers to move further up the scale, they might be so good compared to std that you feel the expense of better tailored pckages justified.
You techies have a point there... the average *joe bloggs* is merely looking for awe-inspiring and confident handling, train-like clutching on the windies...
This is my view, and its one that I spent a lot time working out:
The rear tyre contact patch must be at least 10% more on low profiles on 18's to equal that of larger sidewall'd spread/flex running on 16's.
The front need medium stiffness in sidewalls, and an overall flowing grip, like good-years.
Rear camber should be at least 1-2 degrees negative camber to keep contact patch at optimum on bends...
Front camber should be dead on 0 degrees...
Front toe-out should be 1-2% out from rear toe-in..
Shocks on rear should be set around the 3 quarters way up on stiffness and right height should be slightly higher than front to allow weight shift to buffer at acceleration rather than hit hard on lowered setups.
Shocks on front should be set around 60%-80% stiffness to keep rebound controlled at high speed cornering...
Rear tyres on a tivver should be around 275's on a 35 profile on 18's and fronts should be 255's on a profile of either 30-35.
Also poly-bushes are another serious advantage in seriously optimizing reflection, but rose-jointing is all good for those serious about tracking, road use not exactly friendly on a rose-joint setup, but under the right skilled driver can reap rewards...
The other thing I've noticed, is that upgrade the wheels to 9'Js on the rear is a must, it not only allows the 275's to fit but also provides more distribution of wight downforce on acceleration...
Tivvers are front-engined as we know, but with the right setup the weight shift balances things out just right for 350lb/ft on a 1200-1300kg beast...
Anyway, thats all my opinion... I'm sure many who have played around with theirs has their own views...
But my point is, upgrading the suspension is the first bit, theres a lot more you can do about mating her to the road to suit your driving style in the most optimum manner...
And Nitrons are definitley light years ahead of the general sports shocks, you get ohlin level performance at pennies and their rebound/roll delivery is sublime... most sport shocks can only handle a certain amount of oscillation and as heat builds up they get worse, trackers can appreciate this one, nitron/ohlin mono-tube dampers can take a lot more aggression before they start to show signs of weakening performance... and again, remote resovoir systems with fully-blown cooling setups can reap further benefits... but will the average joe-bloggs need it? like you say bugsy, 10% is the serious enthusiast league, the rest are just after sublime road handling and confidence building attributes... but then you have to ask yourself, giving regular drivers increased confidence, is it really wise? because the first thing I would say is that 10mph quicker running at anything 4krpm+ is a ticking time-bomb for those who have no idea who to correct when she snaps on the limit...
This is my view, and its one that I spent a lot time working out:
The rear tyre contact patch must be at least 10% more on low profiles on 18's to equal that of larger sidewall'd spread/flex running on 16's.
The front need medium stiffness in sidewalls, and an overall flowing grip, like good-years.
Rear camber should be at least 1-2 degrees negative camber to keep contact patch at optimum on bends...
Front camber should be dead on 0 degrees...
Front toe-out should be 1-2% out from rear toe-in..
Shocks on rear should be set around the 3 quarters way up on stiffness and right height should be slightly higher than front to allow weight shift to buffer at acceleration rather than hit hard on lowered setups.
Shocks on front should be set around 60%-80% stiffness to keep rebound controlled at high speed cornering...
Rear tyres on a tivver should be around 275's on a 35 profile on 18's and fronts should be 255's on a profile of either 30-35.
Also poly-bushes are another serious advantage in seriously optimizing reflection, but rose-jointing is all good for those serious about tracking, road use not exactly friendly on a rose-joint setup, but under the right skilled driver can reap rewards...
The other thing I've noticed, is that upgrade the wheels to 9'Js on the rear is a must, it not only allows the 275's to fit but also provides more distribution of wight downforce on acceleration...
Tivvers are front-engined as we know, but with the right setup the weight shift balances things out just right for 350lb/ft on a 1200-1300kg beast...
Anyway, thats all my opinion... I'm sure many who have played around with theirs has their own views...
But my point is, upgrading the suspension is the first bit, theres a lot more you can do about mating her to the road to suit your driving style in the most optimum manner...
And Nitrons are definitley light years ahead of the general sports shocks, you get ohlin level performance at pennies and their rebound/roll delivery is sublime... most sport shocks can only handle a certain amount of oscillation and as heat builds up they get worse, trackers can appreciate this one, nitron/ohlin mono-tube dampers can take a lot more aggression before they start to show signs of weakening performance... and again, remote resovoir systems with fully-blown cooling setups can reap further benefits... but will the average joe-bloggs need it? like you say bugsy, 10% is the serious enthusiast league, the rest are just after sublime road handling and confidence building attributes... but then you have to ask yourself, giving regular drivers increased confidence, is it really wise? because the first thing I would say is that 10mph quicker running at anything 4krpm+ is a ticking time-bomb for those who have no idea who to correct when she snaps on the limit...
Pies said:
.. the jump from std to properly set up avos was so great that they decided on going the next step too .. I offer a part exchange on that route so the customer doesn't lose out.
.
Noted for reference
I'm sure most places offer this type of service if you ask, i can't believe i'm the only one.
can't see why it's not widespread .. where do all the old dampers go? I normally advertise mine on ebay so the owners can see exactly how much they go for .. then i give them back what i get All the comments are noted and I am really pleased with the logical arguments posed by Ash and Joo.
I can have a set of Ohlins for my S and could check them out but I wanted an impartial view from a non contentious source.
If monotube shocks performance justify the extra cost then the truth will out and I will push that route because as Ash says, these are powerful cars and having the confidence of better handling in extreme situations could be worth the extra money.
On the subject of part exchanges, if market forces demand this sort of deal, then so be it.
Mind you, if this experiment proves the point,I will have to bring forward the new Gaz monotube shocks a bit quicker than I first thought.
I can have a set of Ohlins for my S and could check them out but I wanted an impartial view from a non contentious source.
If monotube shocks performance justify the extra cost then the truth will out and I will push that route because as Ash says, these are powerful cars and having the confidence of better handling in extreme situations could be worth the extra money.
On the subject of part exchanges, if market forces demand this sort of deal, then so be it.
Mind you, if this experiment proves the point,I will have to bring forward the new Gaz monotube shocks a bit quicker than I first thought.
a measured response bugsy 
lol the truth's out already though .. they're justified to those people who need the extra performance (or are swayed by labels, they are out there too) .. i dont think that point needs testing!
your road driver who's doing no track day stuff probably will tell you they aren't justified .. but if you repeated the test with a really hard road / track charger then you'd get a different reaction and answer. That's why there's a market full of choices.
lol the truth's out already though .. they're justified to those people who need the extra performance (or are swayed by labels, they are out there too) .. i dont think that point needs testing! your road driver who's doing no track day stuff probably will tell you they aren't justified .. but if you repeated the test with a really hard road / track charger then you'd get a different reaction and answer. That's why there's a market full of choices.
How have people found the reliability of Ohlins shocks? My only experience with them has been on an RSV Mille R motorbike. Many owners had problems with seals failing when those on the standard shocker were absolutely fine.
I don't know anyone who uses Ohlins type shocks in my race series but loads are on AVO's including me. I love them. I know I race in an 'old banger' series but myself and others have spent alot of money on our cars. If it was say an extra 2k to go from Avo's to Ohlins and get a decent improvement then I would imagine that people would have.
Scott
I don't know anyone who uses Ohlins type shocks in my race series but loads are on AVO's including me. I love them. I know I race in an 'old banger' series but myself and others have spent alot of money on our cars. If it was say an extra 2k to go from Avo's to Ohlins and get a decent improvement then I would imagine that people would have.
Scott
My point in all these questions to customers and experts alike is, have we gone too far in our expectations of our cars versus our capacity to percieve or handle the differences?
Is our quest for more BHP, better braking, better handling necessary?
In my case, yes to most of the above but I do own the least equipped model in the stable.
Is our quest for more BHP, better braking, better handling necessary?
In my case, yes to most of the above but I do own the least equipped model in the stable.
seasider said:
I offer a part exchange on that route so the customer doesn't lose out.
Although the expert
lol.. how much did you pay for them derek? maybe the supplier sorted you out an extra special set
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