Preparation for suspension set up and corner weighting
Discussion
One of the things I'd like to sort next year is to get the suspension fully set up and the car corner weighted.
In preparation for this, I'd like to renew suspension/handling related components that may be getting tired (to avoid having to go through it all again!)...the question is what things should I be looking at?
So far I've changed the front upper ball joints and double adjustable shocks all round.
In preparation for this, I'd like to renew suspension/handling related components that may be getting tired (to avoid having to go through it all again!)...the question is what things should I be looking at?
So far I've changed the front upper ball joints and double adjustable shocks all round.
motul1974 said:
I was told by numerous folks in the know not to bother with corner weighting as I'd never notice the difference in a predominantly road car and geo set up was way way more important....just a way of saving you some cash that you could spend on a SHINEY things! Lol
There’s probably some truth in “you’ll never notice the difference” at normal speeds but at speed you would. Corner weighting attempts to put an even footprint of tyre patch on each corner with similar weight transfer by adjusting suspension corner heights which has a direct effect on geo settings in itself, corner weighting and geo should be classed as part of the same thing.
Ok corner weighting isn’t absolutely necessary but it defo helps especially in a light weight car with a light tyre footprint.
If you have adjustable shocks this is the best way to get them working in unison and hopefully predictable handling characteristics.
The problem with using the height from ground to out rigger corners measurement is you have no idea how accurate those riggers are to eachother so corner weighting is the only accurate way of knowing, you can then measure your corners and keep those as a reference for future. It will be all but bob on after that
Perfect balance is worth its weight, on a public road not so important but just knowing is a good thing.
which parts would i change? I would change....nothing!!
first i would set tracking and than have a drive.
if tracking settings are out of spec re-setting will have the most positive effect on your car...for minimal costs....
at least you know where you stand......
balljonts for example do not wear so fast..usually they are built to cope with much heavier cars under much stressfuller conditions.
first i would set tracking and than have a drive.
if tracking settings are out of spec re-setting will have the most positive effect on your car...for minimal costs....
at least you know where you stand......
balljonts for example do not wear so fast..usually they are built to cope with much heavier cars under much stressfuller conditions.
Hedgehopper said:
Make sure that you take your preferred passenger with you when you have it corner weighted.
Good call. Also make sure your oil is midway between min and max, that your fuel tank and windscreen washer bottles are half full, that way you average out any changes in weights as you use fluids! Also make sure your tyre wear is even across axles (not important front to back unless you're anal about the rake).Can anyone think of any others?
Ha Ha, so you always have a passenger on board to make sure its balanced?? Dont forget you must sit in the drivers seat during the set up with an empty bladder to get it spot on for maximum performance. Personally I do everything by tyre temperature- once you have the ride height uniform, and toe in sorted then go for a run on a dry road. Then run your hand across the tyre and see what side is warmest, and then tweak the camber either way to reduce the load on the warmer side until its an even temperature after another run. This will show even tyre contact on average as the suspension moves. Far better than anything static.
blitzracing said:
Ha Ha, so you always have a passenger on board to make sure its balanced?? Dont forget you must sit in the drivers seat during the set up with an empty bladder to get it spot on for maximum performance. Personally I do everything by tyre temperature- once you have the ride height uniform, and toe in sorted then go for a run on a dry road. Then run your hand across the tyre and see what side is warmest, and then tweak the camber either way to reduce the load on the warmer side until its an even temperature after another run. This will show even tyre contact on average as the suspension moves. Far better than anything static.
You may well laugh about having a passenger on board, Jools, but my car definitely handles better on track days with a passenger on board, even though it was corner weighted with just me on board. I can get much closer to the limit of grip, and it corners better even while in a full four wheel slide. Ok, I offer nothing as scientific as lap times or videos, but you just know when the car is more balanced.
Take your points about tyre temperatures - I check mine regularly when I come into the pits. Mat Smith has set mine up with about 1 degree of negative camber and it seems to be a good compromise for both road and track.
For those reading this and thinking "wot?", our Chimaeras are seriously sensitive to the toe, castor and camber being even a little bit out, and the handling can be turned from "killing machine" to "planted" with one session on the four wheel aligner in the hands of an expert. My expert, mentioned above, always checks all the suspension components are working properly before he even starts the alignment, so no money is wasted to no purpose.
Best £90 I spent on the car, and it wasn't even on something shiney.
Final point, to all those who think the car looks better with the ride height set lower than it came out of the factory - that too affects the handling, and TVR actually did invest time and money into getting the ride height and suspension set up correct. If you have your car set low, and think it isn't handling too well, I would get the guy doing the four wheel alignment to set the ride height first. And DO use a TVR expert and DON'T take it to Kwik Fit just because they have an offer on this week - they haven't a clue what they are doing with our cars.
QBee said:
You may well laugh about having a passenger on board, Jools, but my car definitely handles better on track days with a passenger on board, even though it was corner weighted with just me on board.
I can get much closer to the limit of grip, and it corners better even while in a full four wheel slide. Ok, I offer nothing as scientific as lap times or videos, but you just know when the car is more balanced.
I wasn't laughing about having a passenger on board changing the characteristics, it's well know that adding mass dulls a car's responses and makes it less twitchy. Also adding 100kg over the rear axle like you've done there will change the balance. I can get much closer to the limit of grip, and it corners better even while in a full four wheel slide. Ok, I offer nothing as scientific as lap times or videos, but you just know when the car is more balanced.
But you've also just shot down an argument for corner weighting ... your car is better in a condition in which it wasn't corner weighted.
I'm not saying that corner weighting is a complete waste of time, if you're chasing those last tenths, or say have a handling inbalance left/right and want to test a few things then checking the cross weights may lead you to a conclusion and help rectify the trait, but generally speaking it's pretty poor value for money.
But people like spending money on race car type things and I would never tell anyone how to spend their money if that's what they want, but you can only make an informed choice if you get all the facts
I would never tell a racing driver that the carbon gear knob he's just bought didn't add that 0.5 second advantage .. if the stopwatch shows it's 0.5secs faster then who cares that it's just the feel good factor of a carbon knob that's done the trick, faster is faster.
Likewise if knowing your corner weights are set up makes you more confident and safer/faster in your car then that's all good.
But for 99 percent of owner/drivers at our level, in our cars, I think there's far better things to spend money on.
spitfire4v8 said:
QBee said:
You may well laugh about having a passenger on board, Jools, but my car definitely handles better on track days with a passenger on board, even though it was corner weighted with just me on board.
I can get much closer to the limit of grip, and it corners better even while in a full four wheel slide. Ok, I offer nothing as scientific as lap times or videos, but you just know when the car is more balanced.
I wasn't laughing about having a passenger on board changing the characteristics, it's well know that adding mass dulls a car's responses and makes it less twitchy. Also adding 100kg over the rear axle like you've done there will change the balance. I can get much closer to the limit of grip, and it corners better even while in a full four wheel slide. Ok, I offer nothing as scientific as lap times or videos, but you just know when the car is more balanced.
But you've also just shot down an argument for corner weighting ... your car is better in a condition in which it wasn't corner weighted.
I'm not saying that corner weighting is a complete waste of time, if you're chasing those last tenths, or say have a handling inbalance left/right and want to test a few things then checking the cross weights may lead you to a conclusion and help rectify the trait, but generally speaking it's pretty poor value for money.
But people like spending money on race car type things and I would never tell anyone how to spend their money if that's what they want, but you can only make an informed choice if you get all the facts
I would never tell a racing driver that the carbon gear knob he's just bought didn't add that 0.5 second advantage .. if the stopwatch shows it's 0.5secs faster then who cares that it's just the feel good factor of a carbon knob that's done the trick, faster is faster.
Likewise if knowing your corner weights are set up makes you more confident and safer/faster in your car then that's all good.
But for 99 percent of owner/drivers at our level, in our cars, I think there's far better things to spend money on.
If I think about it, I guess the extra 50-60 kg weight of my (usually) female passenger is just helping the car's rear wheels to stay stuck to the track better, as the most common OMG experience in a TVR is when the scenery changes without warning from what is ahead of you to where you've just been.
I still remember traveling along the grass verge of the A453 backwards at 60 mph when i was 17. My parents had asked me to collect them from East Midlands Airport at the end of their holiday, and I had been given the keys to their Sunbeam Imp Sport for the purpose. To those who remember that Scottish classic, handling was an optional extra, and with the engine at the rear, most sensible drivers kept two full paving slabs in the (front) boot. Despite having said paving extra, I still managed to spin the car on a bend whilst driving with my customary 17 year-old gusto, but without my 65 year-old skill and experience. To this day I don't know how I managed to end up continuing towards Castle Donington without braking, stopping or hitting anything.
In my experience. any Chimaera without a full four wheel alignment is capable of delivering a driving experience similar to an Imp Sport without warning.
QBee said:
I had been given the keys to their Sunbeam Imp Sport
When I were a lad I had a spitfire4 (1963 vintage, I still have it actually) .. and my friend had a Sunbeam Stilleto .. how we are both still alive now is a miracle for just the reasons you mentioned .. neither car was blessed with handling excellence.However, those cars taught you to repsect them, that if you did something foolish they'd bite back. Fortunately speeds were much reduced back then, we thought we were flying at 60mph! .. but lessons learned in those kinds of cars are remembered for a long time!
I think everyone should have their first year of motoring in an Imp, or Spitfire or similar. If you survive that then you've earned the right to progress to level 2!
If survival is the name of the game I’d defo be corner weighting the car, not so much because I’ll notice anything but because it’s nice to know the car is actually level and the weights on each wheel are accurate, this should give the car better balanced braking if nothing else, or confirm your car is at least sitting on the road evenly.
Almost every race track I know of has a flat floor area to be able to do this work which shows it is important for people going at speed.
I’ve rarely known a perfectly flat road in the U.K. so as Joolz mentions there’s better things to spend money but in an ideal world you would do this as part of trying to hit the sweet spot on any geo set up.
If you’ve spent money rebuilding or replacing components, adding expensive shocks etc etc the cost of corner weighting is negligible considering it’s taking you from a blind situation to knowing exactly how much weight sits on each wheel.
Raising a corner by only a few mm will transfer weight so if your riggers are 10mm out of spec from each other which could be just 5mm each side you can see how replacing shocks or anything else is never going to be perfect if you go by the floor to rigger way of setting ride heights as it’s a guess.
That’s my reason for why it’s money well spent. It’s accurate as it can be.
Almost every race track I know of has a flat floor area to be able to do this work which shows it is important for people going at speed.
I’ve rarely known a perfectly flat road in the U.K. so as Joolz mentions there’s better things to spend money but in an ideal world you would do this as part of trying to hit the sweet spot on any geo set up.
If you’ve spent money rebuilding or replacing components, adding expensive shocks etc etc the cost of corner weighting is negligible considering it’s taking you from a blind situation to knowing exactly how much weight sits on each wheel.
Raising a corner by only a few mm will transfer weight so if your riggers are 10mm out of spec from each other which could be just 5mm each side you can see how replacing shocks or anything else is never going to be perfect if you go by the floor to rigger way of setting ride heights as it’s a guess.
That’s my reason for why it’s money well spent. It’s accurate as it can be.
QBee said:
Final point, to all those who think the car looks better with the ride height set lower than it came out of the factory - that too affects the handling, and TVR actually did invest time and money into getting the ride height and suspension set up correct..
. Well i would have to dispute this as i have had my ride height lower than standard for many years, not silly low. It makes the car feel more planted and much improved. I have no technical reason for this just my experience. Recently i raised it again while i was maintaining the coil overs only by a few mm back to near the original settings and it felt poorer in comparison IMO, so i plan to lower it again in the spring bias towards the front. Everything is maintained in top order incl alignment bushes ARB's etc, so its not compensating for anything else its just a more planted better handling car!
Andy JB said:
QBee said:
Final point, to all those who think the car looks better with the ride height set lower than it came out of the factory - that too affects the handling, and TVR actually did invest time and money into getting the ride height and suspension set up correct..
. Well i would have to dispute this as i have had my ride height lower than standard for many years, not silly low. It makes the car feel more planted and much improved. I have no technical reason for this just my experience. Recently i raised it again while i was maintaining the coil overs only by a few mm back to near the original settings and it felt poorer in comparison IMO, so i plan to lower it again in the spring bias towards the front. Everything is maintained in top order incl alignment bushes ARB's etc, so its not compensating for anything else its just a more planted better handling car!
If it helps, because of the varying wheel and tyre set ups used, my TVR guy, when setting ride height, gets the rear lower wishbones dead horizontal by adjusting the rear ride height, then sets the fronts so the outrigger corners (I think) are about 15mm lower at the front than at the back. The front wishbones won't be level.
The whole level wishbone thing is completely irrelevant in my opinion anyway, yet some people are anal about it.
What matters more is : is your car usable? For instance .. if you set the bottom wishbones level does that ride height still allow you to go the places you want to without grounding out? If you set them level, but you can't use the car, why is that good? It isn't.
I've always used the theme of : set the height to whatever you need to get the job done for your circumstances / regular driving. That probably means your bottom wishbones aren't level. They won't be level when you sit in the car anyway, or go over a bump, or any deviation from how they were initially set as a static car. What ultimately matters is : is the car safe (priority) and can you use it, and then can you achieve any particular handling balance by massaging the settings accordingly.
Also to the people who say set the bottom wishbones level .. why is the bottom arm any more important than the top arm? If you say set the bottom arm level you must have a reason otherwise why say it. The top and bottom arms are linked and work as a system. It's like people saying they don't like engine power, they like torque. What they mean is they like power from low revs. Power is what matters, but you can't separate that from torque. They're linked by rpm. Your top and bottom arms are linked by the hub/upright.
I seem to plough a lone furrow on suspension set up, against the flow of internet wisdom.
But then 15 years ago I struggled to get people into aftermarket ECUs against the internet wisdom, and now they're flavour of the month.
Funny thing t'internet.
What matters more is : is your car usable? For instance .. if you set the bottom wishbones level does that ride height still allow you to go the places you want to without grounding out? If you set them level, but you can't use the car, why is that good? It isn't.
I've always used the theme of : set the height to whatever you need to get the job done for your circumstances / regular driving. That probably means your bottom wishbones aren't level. They won't be level when you sit in the car anyway, or go over a bump, or any deviation from how they were initially set as a static car. What ultimately matters is : is the car safe (priority) and can you use it, and then can you achieve any particular handling balance by massaging the settings accordingly.
Also to the people who say set the bottom wishbones level .. why is the bottom arm any more important than the top arm? If you say set the bottom arm level you must have a reason otherwise why say it. The top and bottom arms are linked and work as a system. It's like people saying they don't like engine power, they like torque. What they mean is they like power from low revs. Power is what matters, but you can't separate that from torque. They're linked by rpm. Your top and bottom arms are linked by the hub/upright.
I seem to plough a lone furrow on suspension set up, against the flow of internet wisdom.
But then 15 years ago I struggled to get people into aftermarket ECUs against the internet wisdom, and now they're flavour of the month.
Funny thing t'internet.
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