Suspension set advice
Discussion
My TVR S is a great all round sports car that generally handles very well, and with the right tyres is also very fast. I have been doing trackdays for a number of years with it now and it has some characteristics which I am not so happy about, and which I have tried numerous spring and damper alterations to eradicate, but so far have only achieved limited success. With the car set up better I could enjoy it much more.
Basically when cornering hard and with either standard or slightly stiffer springs, the body rolls significantly and the steering loads up excessively (which many S owners complain about). To eradicate this tendancy, I have fitted progressively stiffer springs to the point where I have 700lb/in in the rear and 600lb/in at the front(the rates of which are now too high for the dampers to work properly).....I know many people say you should have the higher rate in the front, but the car does not feel right to me this way round, and its not so simple to simply talk about spring rates, because the geometry is different front (wish bones) to rear (trailing arms), so whilst I have not yet bothered to measure the spring leverage angles and geometry, it is highly possible the spring rate needs to be higher. Also the rear axle weight of the car is about 40kgs heavier than the front unladen. The petrol tank is just behind the rear axle and the passengers mass is biased to the rear....so on a laden trackday condition, the rear will be about 565kg and the front about 515kg.
With the higher spring rates I have found that disconnecting the front anti roll bar makes a significant improvement to turn in, but the steering is still too heavy, turn in is not sharp enough, and there is still more body roll than I`d like. The other problem mentioned before is the spring rates are too high for the dampers so the ride on anything than a good road is unpleasant....I know from my numerous experiments that 450lb/in seems to work very well with the dampers....so after all this, I am thinking about reducing the spring rates to 450lb/in front and rear...maybe 500lb/in at the rear, and fitting a rear anti roll bar. I have also pondered the idea of moving the pick up point of the spring/shock on the rear trailing arms to directly above the training arm connection, instead of their present forward location just above the arm pivots. My reasoning is that a lower spring rate could be used due to the increased leverage which would retain the roll stiffness and allow the dampers to work correctly with the softer springs....but it is a big job and not one to get wrong.
I have also noticed the steering track control arms do not sit parallel to the lower front wishbones, ie the steering rack might be too low?...I would not be surprised if TVR did not spend the time getting this right...compromising with standard off the shelf parts and production deadlines, and maybe not the right technical ability?
I make the car sound like a bag of nails....it`s still is more fun to drive than a Z4 (although to be fair I have not driven a Z4M or M coupe), S2000, an MX5, and even my Focus RS, which is a fantastic all round performance car....and its as quick as the RS, with its BOA engine, both in a straight line and around corners.
What is really sparking this off is I had a go in a Caterham at the last trackday I did, and it turned in so well, I have either got to go mid engined or Caterhan esq (not practical enough), but I still think that the right mods could sort the TVR out.
Help!...or am I flogging a dead horse?
Basically when cornering hard and with either standard or slightly stiffer springs, the body rolls significantly and the steering loads up excessively (which many S owners complain about). To eradicate this tendancy, I have fitted progressively stiffer springs to the point where I have 700lb/in in the rear and 600lb/in at the front(the rates of which are now too high for the dampers to work properly).....I know many people say you should have the higher rate in the front, but the car does not feel right to me this way round, and its not so simple to simply talk about spring rates, because the geometry is different front (wish bones) to rear (trailing arms), so whilst I have not yet bothered to measure the spring leverage angles and geometry, it is highly possible the spring rate needs to be higher. Also the rear axle weight of the car is about 40kgs heavier than the front unladen. The petrol tank is just behind the rear axle and the passengers mass is biased to the rear....so on a laden trackday condition, the rear will be about 565kg and the front about 515kg.
With the higher spring rates I have found that disconnecting the front anti roll bar makes a significant improvement to turn in, but the steering is still too heavy, turn in is not sharp enough, and there is still more body roll than I`d like. The other problem mentioned before is the spring rates are too high for the dampers so the ride on anything than a good road is unpleasant....I know from my numerous experiments that 450lb/in seems to work very well with the dampers....so after all this, I am thinking about reducing the spring rates to 450lb/in front and rear...maybe 500lb/in at the rear, and fitting a rear anti roll bar. I have also pondered the idea of moving the pick up point of the spring/shock on the rear trailing arms to directly above the training arm connection, instead of their present forward location just above the arm pivots. My reasoning is that a lower spring rate could be used due to the increased leverage which would retain the roll stiffness and allow the dampers to work correctly with the softer springs....but it is a big job and not one to get wrong.
I have also noticed the steering track control arms do not sit parallel to the lower front wishbones, ie the steering rack might be too low?...I would not be surprised if TVR did not spend the time getting this right...compromising with standard off the shelf parts and production deadlines, and maybe not the right technical ability?
I make the car sound like a bag of nails....it`s still is more fun to drive than a Z4 (although to be fair I have not driven a Z4M or M coupe), S2000, an MX5, and even my Focus RS, which is a fantastic all round performance car....and its as quick as the RS, with its BOA engine, both in a straight line and around corners.
What is really sparking this off is I had a go in a Caterham at the last trackday I did, and it turned in so well, I have either got to go mid engined or Caterhan esq (not practical enough), but I still think that the right mods could sort the TVR out.
Help!...or am I flogging a dead horse?
Ha Ha Sam...although I guessed I that reply was inevitable.
I see you had a Griffith which has an asthmatic engine, but a good chassis, with some simple mods to the rear, as far as I am aware.
I have pretty well decided to make the S back into a good traditional road sports car, which is what it is, and when our extention is built, build a trackday special.
I see you had a Griffith which has an asthmatic engine, but a good chassis, with some simple mods to the rear, as far as I am aware.
I have pretty well decided to make the S back into a good traditional road sports car, which is what it is, and when our extention is built, build a trackday special.
CTE said:
I see you had a Griffith which has an asthmatic engine, but a good chassis, with some simple mods to the rear, as far as I am aware.
I think you may have that the wrong way round... the engine in mine was pretty fierce (I certainly wouldn't have decribed it as asthmatic!), but the chassis was the most lamentable abortion I've ever encountered. The front-end geometry was terrible, with way too much tramlining and kickback, even once you'd got the bump-steer dialled out, and the rear was only good if your definition of 'simple mods' is re-engineering the geometry to limit the unpredictable roll centre movement that is inherent with the standard design. Either that or fit springs stiff enough that the suspension can't move far enough to get into trouble...The man you want to talk to is GreenV8s, but unfortunately he seems to have suddenly stopped posting here on PistonHeads back in December (hopefully not for any untoward reasons).
Joking aside, though, I think you're up against the fact that the basic front upright and steering geometry on the TVR is not the best and most of your issues with the way the steering loads up will stem from that. Turn-in can probably be improved by playing with the damping (particularly if you invest in dampers good enough to allow separate adjustment of high- and low- speed damping), but you'll probably find that it will expose shortcomings with the semi-trailing arm rear as the chassis loads up.
If you want razor-sharp handling precision, you'll need a Caterham, Lotus or similar; I think you're right to
keep the TVR to what it's good at: a nice, traditional sports-tourer.
Thanks for that Sam.....by asthmatic I simply recall my experience with the 4 and 4.5ltr engines...loads of low down torque, a great sound, and just when you think they are about to really come alive, the power drops off and the engine does not want to rev above 4500 to 5000 rpm.
I guess TVR were always working with off the shelf components, but you cannot help thinking they should have done better....probably did not have the right technical knowhow.
Funny though, for all my cars faults, I quite regularly pass lower powered Lotus Elises and Lotus 7 esq cars on trackdays....it holds its own fine in the corners, although I am having to drive the car with some effort. I clearly remember watching two Elises infront of me last year, which I had caught, only to watch the leader spin off! I then passed the second car.
We live quite near to Hethel, and indeed my missus works there. I had a Lotus trackday experience in an Elise and vowed I wanted one after that, but then bought a RS Focus?...more boot space etc. Anyhow, after I had done my best to potter round the test track, the instructor took over, and I must admit there were a oouple of sections of the track where he put the car through the twisties at unbelievable speed. Very impressed.
I guess TVR were always working with off the shelf components, but you cannot help thinking they should have done better....probably did not have the right technical knowhow.
Funny though, for all my cars faults, I quite regularly pass lower powered Lotus Elises and Lotus 7 esq cars on trackdays....it holds its own fine in the corners, although I am having to drive the car with some effort. I clearly remember watching two Elises infront of me last year, which I had caught, only to watch the leader spin off! I then passed the second car.
We live quite near to Hethel, and indeed my missus works there. I had a Lotus trackday experience in an Elise and vowed I wanted one after that, but then bought a RS Focus?...more boot space etc. Anyhow, after I had done my best to potter round the test track, the instructor took over, and I must admit there were a oouple of sections of the track where he put the car through the twisties at unbelievable speed. Very impressed.
CTE said:
...I quite regularly pass lower powered Lotus Elises and Lotus 7 esq cars on trackdays....it holds its own fine in the corners.
The big problem with the 'Seven' type cars in particular (an the Elise to a lesser extent) is simply the lack of power vs. aerodynamic drag. By the time you reach a 3-figure speed in either, there's not a lot of power left for acceleration as it's all being soaked up in drag. Since you're not allowed to overtake on corners on most track days, high-powered cars like TVR's will naturally have the legs on the straights and you just have to get used to them getting in your way on the bends - there's no denying that the Griffith is a very effective dragster in the mid range.
Road use is a very different matter though - I used to be faster point-to-point in the Leon Cupra I had as a company car at the time than in the TVR!
SSC Stylus (if they still exist) ?
http://www.pistonheads.com/doc.asp?c=112&i=735...
What happened to this, one of the links looks like it goes somewhere oriental now
http://www.pistonheads.com/doc.asp?c=112&i=735...
What happened to this, one of the links looks like it goes somewhere oriental now
CTE said:
Good idea Richard....but strangely you have gone from Stylus to Griffith, although the Griff is a lot more practical....and no matter what its short comings might be, it makes a great sound which does not require you to drive at stupid speeds to have loads of fun.
It was a Fury actually (even more TVR S like in its appearance than the Stylus). The bad bit with it was having a live axle, it didn't feel happy on bumpy roads because of unspring weight. Practical, yes. That was the reason for changing, practicality! The ability to cruise and do longer runs. Comfier on b-roads too, although all comparisons at cruising speed
If I had discovered PH whilst still having the Fury it would have been turbocharged/supercharged or changed to a Hayabusa (then turbocharged
), so a TVR would then be slow 
Ironically after the downer that Sam puts on TVR dynamics, the Griff vs MX5 in EVO this month was interesting. Even with getting out braked with the 260mm disks vs a 290mm setup with ABS, the laptime was quite good. Only a tiny bit slower than a Porksta S in the times with its lower C of G, massive tyres and brakes. And probably the same bhp too, assuming the Griff wasn't twiddled with and a recent ish Porka.
BliarOut said:
I have a couple of images saved of your settings you posted once, so one day I can just get in touch and go "I wan wanna dem" On a similar note EVO are supposed to be taking their Griff to some Lotus bod, so it'll be interesting to see what they come up with....
RichardD said:
BliarOut said:
I have a couple of images saved of your settings you posted once, so one day I can just get in touch and go "I wan wanna dem" On a similar note EVO are supposed to be taking their Griff to some Lotus bod, so it'll be interesting to see what they come up with....
It'll cost me another £200 for Chris to do a basic geo, but I know it will be money very well spent 
RichardD said:
Ironically after the downer that Sam puts on TVR dynamics, the Griff vs MX5 in EVO this month was interesting.
About what you'd expect, surely? The Boxter has similar power, but about 300 kilos more weight (that's equivalent to having 3 fat mates as passengers) and only 75% of the torque... yet it still manages to go slightly quicker due to a more competent chassis?And don't forget that race tracks are nice and smooth. Where the Griffith goes to pieces is on traditional British A- and B- roads, when it encounters rough, cambered or rutted tarmac.
Sam_68 said:
...About what you'd expect, surely? The Boxter has similar power, but about 300 kilos more weight (that's equivalent to having 3 fat mates as passengers) and only 75% of the torque... yet it still manages to go slightly quicker due to a more competent chassis?
And don't forget that race tracks are nice and smooth. Where the Griffith goes to pieces is on traditional British A- and B- roads, when it encounters rough, cambered or rutted tarmac.
From the info I've found the latest Boxster S is about +300kgs, but then again that would actually have 15% more power than the TVR (unless it was tweaked). An older one with more equal power, would be +250kg.And don't forget that race tracks are nice and smooth. Where the Griffith goes to pieces is on traditional British A- and B- roads, when it encounters rough, cambered or rutted tarmac.
Chassis, yes of course, but going with the times, standard tyres are wider with lower profile rubber and corresponding bigger brakes. Stiffer suspension helps too. If these were upgraded from standard it would then be interesting to compare times then.
Maybe I read it wrong, but your last line does imply an expectation of being a rally car!
RichardD said:
From the info I've found the latest Boxster S is about +300kgs, but then again that would actually have 15% more power than the TVR (unless it was tweaked).
That rather depends on what horsepower you are assessing the TVR to have, though, doesn't it? If you were foolish enough to believe TVR's claims, the Griffith 500 had 340bhp (so 20bhp more than the Porsche), but then it's well known that TVR's dyno was routinely calibrated against one of the more elderly Blackpool donkeys...
RichardD said:
Stiffer suspension helps too.
That's an interesting comment, particularly in light of the OP's comments. There is an argument (supported by one A.C.B. Chapman, amongst others), that stiffer suspension is a very effective crutch for the incompetent suspension designer, but that a well-designed car should have the most supple suspension possible, consistent with the conflicting requirements of camber control, a stable aero platform and the limitations of the dampers to control the unsprung weight.But that's a debate for another thread, perhaps...
RichardD said:
Maybe I read it wrong, but your last line does imply an expectation of being a rally car!
No, merely realistic road use on typical British tarmac.Sam_68 said:
RichardD said:
From the info I've found the latest Boxster S is about +300kgs, but then again that would actually have 15% more power than the TVR (unless it was tweaked).
That rather depends on what horsepower you are assessing the TVR to have, though, doesn't it? If you were foolish enough to believe TVR's claims, the Griffith 500 had 340bhp (so 20bhp more than the Porsche), but then it's well known that TVR's dyno was routinely calibrated against one of the more elderly Blackpool donkeys...
Sam_68 said:
RichardD said:
Stiffer suspension helps too.
That's an interesting comment, particularly in light of the OP's comments. There is an argument (supported by one A.C.B. Chapman, amongst others), that stiffer suspension is a very effective crutch for the incompetent suspension designer, but that a well-designed car should have the most supple suspension possible, consistent with the conflicting requirements of camber control, a stable aero platform and the limitations of the dampers to control the unsprung weight.But that's a debate for another thread, perhaps...
Your statements are a bit harsh on suspension as a suspension designer probably won't be able to dictate the dimensions of a car, its engine and position, so has to work within certain limitations.
RichardD said:
Didn't I imply to work out a number that is 15% less than the latest Boxster S figure as a ballpark TVR one?
You did. But I'm sure you'd have 'implied' TVR's 'official' figures were correct, had it better suited your arguments. My point was that with TVR power outputs, it's a case of pick a number, any number... (well, any number between about 240-340, for the Griff 500). Their engines are almost as inconsistent as their chassis.
Actually, that's unfair of me... the Speed 6 engine was very consistent indeed. You could rely on it eating its own internals, regular as clockwork, about every 25,000 miles.
RichardD said:
The more the power rating is reduced, the better that EVO lap looks again
Perhaps they should have disconnected a couple of plug leads and it would have gone a bit quicker? 
The Griffith's strength (though perhaps its weakness, too, as it completely overwhelms the chassis), of course, is torque rather than outright power...
RichardD said:
Suspension stiffness in the context of the laptime and EVO's comments with the TVR being too soft for track work.
(Back on topic...)Yet it's no softer (indeed it's noticeably stiffer) than the Lotuses, several examples of which are quicker with substantially lower power:weight ratios. And are you suggesting that the Jaguar XFR (identical power:weight ratio to your 'detuned' Griffith, over 800 kilos (
) heavier, yet slightly faster) is better suited to track work?Even on the track, 'Chapman's Rule' was that suspension should be as soft as possible commensurate with other requirements and it was only when aero came to the fore that spring rates went through the roof.
Unfortunately, people often assume that just because a Formula 1 car runs solid suspension, the same is a good idea for a road/track day car. With a competent suspension design and set-up, you'd often be surprised...
CTE said:
Help!...or am I flogging a dead horse?
No, you're not. You'll never get the best part of a ton of S to handle like a Caterham, but they are hugely underrated dynamically.
One thing I would say is that the chassis isn't that stiff on the S, so continually upping the spring rates is likely to be counter productive, certainly on the road.
With regards the steering, bear in mind that it has a heavy-ish engine quite well forward and no power assistance. It's never going to be that light and I found on mine that the rather weighty steering came with very good slip angle feedback. It would give a very clear indication of the remaining grip near the limit - presumably thanks to a healthy degree of caster - even though the overall feedback was nothing to write home about.
Oh, and they also seem to be quite sensitive to front and rear ride height. A so-called expert set mine up with a huge amount of rake and it handled appallingly to start with. After equalising the ride heights (in a rather unscientific way) it was far better.
OK, enough fun baiting the Rock Apes (for now ).... some serious observations:
Decent dampers, properly set up, will make a world of difference, but more importantly decent dampers are re-valveable.
Dampers should be matched to the springs, not the other way around.
You can also achieve similar effect on turn-in by stiffening the front dampers (since this will give you initial roll resistance as you turn in, which then progressively reduces as the damper compresses and the chassis adopts a ‘set’ in the corner). Ideally, you want dampers with separately adjustable high- and low- speed damping, since you can then stiffen the low speed (roll) damping without affecting the high speed (ride quality) damping, but the cost may be a bit eye-watering for you.
Unfortunately the steering weight is almost certainly more a function of the front upright geometry (though obviously the ratio of front:rear roll stiffness will affect it to some extent, as it will influence the amount of weight being transferred onto the outside front corner... but we’re back to carts and horses; you can’t allow diagonal weight transfer to be dictated by steering feel, as the former is crucial to basic handling balance). You would probably need to reduce the caster, KPI and/or the kingpin offset (the latter by changing the wheel offset) to make a significant difference, but there will be side-effects to any changes to these factors.
FWIIW, the S-series has similar caster and KPI to the Elise, which is fine for a car with little weight over the front wheels, but not for one with a bloody great boat anchor up front. My gut feeling would be that you would need to reduce the KPI (the S-series’ 13 degrees is pretty hefty, whereas – and contrary to Race Tech’s comments above that it has a ‘healthy degree’ – standard caster is pretty reasonable at 3.5 degrees) and reduce the kingpin offset, as a start, but that would need new uprights as well as new wheels (and reducing the KPI will tend to increase the kingpin offset, so you end up chasing yourself in circles and would probably end up needing a complete redesign of the whole front suspension, including uprights and hubs).
edited to add: I've just spotted from the manufacturer's data that the KPI of the V8S is listed as 6 degrees, instead of the 13 degrees of the V6 engined cars I quoted above. Might be worth investigating the possibility of using V8S geometry and front suspension components?
If you don't want to get into that level of engineering, then maybe try reducing the caster a bit (make sure you have the same amount either side an that it is to factory spec, first, though), then try finding some wheels that give slightly less kingpin offset.
I assume you have already tried playing with tyre pressures (increasing the front pressure may help with steering weight)? Tyre selection also makes a difference, but it's a bit hit-and-miss unless you know someone with a similar car who can recommend some.
And as Race Tech says, the TVR chassis isn't the stiffest, so if you beef up the spings and dampers too far, you'll just end up with the chassis and tyres acting as undamped springs, which won't improve matters at all.
You could apply the Chapman theorem that anything can be made to handle if you don’t allow the suspension to move, but it will end up heavily compromised as a road car (as, to be fair, are almost all genuine ‘track’ cars), but it’ll never be as good as something like a Caterham that is fundamentally better suited to track use.
I’m a big believer in Darwinism, personally – if you want a racing pigeon, you don’t embark on a selective breeding programme for parrots.
...though being able to ask for directions when they get lost might have possibilities.
).... some serious observations:CTE said:
...the rates of which are now too high for the dampers to work properly....
Cart. Horse. The one that neighs goes in front...Decent dampers, properly set up, will make a world of difference, but more importantly decent dampers are re-valveable.
Dampers should be matched to the springs, not the other way around.
CTE said:
... whilst I have not yet bothered to measure the spring leverage angles and geometry
You need to. We may be able to give much more meaningful advice if we know the wheel rates.CTE said:
... disconnecting the front anti roll bar makes a significant improvement to turn in, but the steering is still too heavy, turn in is not sharp enough, and there is still more body roll than I`d like.
Logic says, therefore, that more front roll stiffness is helping, but since you say that the road ride is unpleasant, you should be adding that stiffness with the ARB (which has more influence on roll and less on ride quality than achieving the same amount of roll stiffness by means of the main springs).You can also achieve similar effect on turn-in by stiffening the front dampers (since this will give you initial roll resistance as you turn in, which then progressively reduces as the damper compresses and the chassis adopts a ‘set’ in the corner). Ideally, you want dampers with separately adjustable high- and low- speed damping, since you can then stiffen the low speed (roll) damping without affecting the high speed (ride quality) damping, but the cost may be a bit eye-watering for you.
Unfortunately the steering weight is almost certainly more a function of the front upright geometry (though obviously the ratio of front:rear roll stiffness will affect it to some extent, as it will influence the amount of weight being transferred onto the outside front corner... but we’re back to carts and horses; you can’t allow diagonal weight transfer to be dictated by steering feel, as the former is crucial to basic handling balance). You would probably need to reduce the caster, KPI and/or the kingpin offset (the latter by changing the wheel offset) to make a significant difference, but there will be side-effects to any changes to these factors.
FWIIW, the S-series has similar caster and KPI to the Elise, which is fine for a car with little weight over the front wheels, but not for one with a bloody great boat anchor up front. My gut feeling would be that you would need to reduce the KPI (the S-series’ 13 degrees is pretty hefty, whereas – and contrary to Race Tech’s comments above that it has a ‘healthy degree’ – standard caster is pretty reasonable at 3.5 degrees) and reduce the kingpin offset, as a start, but that would need new uprights as well as new wheels (and reducing the KPI will tend to increase the kingpin offset, so you end up chasing yourself in circles and would probably end up needing a complete redesign of the whole front suspension, including uprights and hubs).
edited to add: I've just spotted from the manufacturer's data that the KPI of the V8S is listed as 6 degrees, instead of the 13 degrees of the V6 engined cars I quoted above. Might be worth investigating the possibility of using V8S geometry and front suspension components?
If you don't want to get into that level of engineering, then maybe try reducing the caster a bit (make sure you have the same amount either side an that it is to factory spec, first, though), then try finding some wheels that give slightly less kingpin offset.
I assume you have already tried playing with tyre pressures (increasing the front pressure may help with steering weight)? Tyre selection also makes a difference, but it's a bit hit-and-miss unless you know someone with a similar car who can recommend some.
CTE said:
...The other problem mentioned before is the spring rates are too high for the dampers so the ride on anything than a good road is unpleasant....I know from my numerous experiments that 450lb/in seems to work very well with the dampers....so after all this, I am thinking about reducing the spring rates to 450lb/in front and rear...maybe 500lb/in at the rear, and fitting a rear anti roll bar.
As above; valve the dampers to match the springs, not the other way around, but are you sure the ‘unpleasant’ ride is down to the dampers? It’s difficult to say without knowing the wheel rates, but I’d unless the TVR suspension gives massive leverages (which I know it certainly doesn’t at the front), I’d expect those sorts of spring rates to give a pretty boneshaking ride (and much degraded grip on rough tarmac) when matched to the correct dampers. Remember that the damper’s job is to control the spring bump and rebound to somewhere close to critical damping, so the correct dampers matched to those spring rates will probably need to be much stiffer than what you have at the moment.And as Race Tech says, the TVR chassis isn't the stiffest, so if you beef up the spings and dampers too far, you'll just end up with the chassis and tyres acting as undamped springs, which won't improve matters at all.
CTE said:
... I have also pondered the idea of moving the pick up point of the spring/shock on the rear trailing arms to directly above the training arm connection, instead of their present forward location just above the arm pivots. My reasoning is that a lower spring rate could be used due to the increased leverage which would retain the roll stiffness and allow the dampers to work correctly with the softer springs....but it is a big job and not one to get wrong.
You should be able to juggle the front and rear roll stiffnesses adequately by means of spring and ARB rates, without buggering about moving pick-ups. The only reason I’d resort to moving the pick-ups would be if the current spring/damper geometry gave a dramatically falling rate that needed correcting.CTE said:
...I have also noticed the steering track control arms do not sit parallel to the lower front wishbones, ie the steering rack might be too low?
It’s not essential that the TCA’s are parallel to the lower wishbones – correct geometry can be achieved with different rack placement, provided the lengths of the TCA’s have been worked out properly and the rack positions so that the arcs they move through don’t conflict with the arcs of the wishbones, but certainly if you haven’t checked the car for bump steer you should do so; TVR’s being what they are, I would be nothing short of astonished if you didn’t find any.CTE said:
...What is really sparking this off is I had a go in a Caterham at the last trackday I did, and it turned in so well, I have either got to go mid engined or Caterhan esq (not practical enough), but I still think that the right mods could sort the TVR out.
Help!...or am I flogging a dead horse?
Joking aside, you need to recognise that the TVR uses inappropriate front upright geometry (dictated by borrowed Ford components, which weren’t even designed for use with double wishbones) and a rear suspension design that even BMW couldn’t get to work to a standard that would be considered acceptable these days.Help!...or am I flogging a dead horse?
You could apply the Chapman theorem that anything can be made to handle if you don’t allow the suspension to move, but it will end up heavily compromised as a road car (as, to be fair, are almost all genuine ‘track’ cars), but it’ll never be as good as something like a Caterham that is fundamentally better suited to track use.
I’m a big believer in Darwinism, personally – if you want a racing pigeon, you don’t embark on a selective breeding programme for parrots.
...though being able to ask for directions when they get lost might have possibilities.
Edited by Sam_68 on Tuesday 13th July 19:20
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