Real world Lateral G and road tyres
Discussion
Arguably the elise is over-tyred at 225 rear and 195 front. Simply going for wider tyres will not necessarily produce more grip.
Initially you should be trying to maximise the contact patch on cornering through a combination of suspension and geo settings - in particular the amount of negative camber. Getting this right should be a greater priority than tyre width. When it rains, having excessively wide tyres on a light car can get interesting (don't equate elises with high downforce cars that run wide tyres)This is particularly important for a road car. If you have 500 bhp and are lighting up the rears every time you use the throttle, that's a different issue.
Interestingly, on standard size exige wheels + slicks, Chris Randall (randy) told me his car was pulling over 2g on the datalogger at the Silverstone 24 hour.
Stay with standard sizes imho.
Initially you should be trying to maximise the contact patch on cornering through a combination of suspension and geo settings - in particular the amount of negative camber. Getting this right should be a greater priority than tyre width. When it rains, having excessively wide tyres on a light car can get interesting (don't equate elises with high downforce cars that run wide tyres)This is particularly important for a road car. If you have 500 bhp and are lighting up the rears every time you use the throttle, that's a different issue.
Interestingly, on standard size exige wheels + slicks, Chris Randall (randy) told me his car was pulling over 2g on the datalogger at the Silverstone 24 hour.
Stay with standard sizes imho.
Scuffers said:
cornering G is a very abused term...(and almost meaningless in the context of a road car)
Absolutely!It's so variable depending upon the condition of the road surface that trying to attached numbers - even relative ones - to it is pointless.
And it's much more important that the car gives you fair warning that it's approaching its limits, and behaves predictably at high slip angles, than it is to generate the highest possible cornering forces.
If we're honest, that's where the Elise falls down... the handling is very good up to a point, but when it comes to on-the-limit handling, there are much more predictable and better-balanced cars out there.
Scuffers said:
welcome to short-wheelbase cars (relatively)
The transverse mid-engine doesn't help, either, mind you.
If you shorten the wheelbase a bit more and fit a heavier transverse engine, you're left with a Lancia Stratos, basically.
Now they are snappy little b
ds at the limit... Scuffers said:
cornering G is a very abused term...(and almost meaningless in the context of a road car)
Yup. If you're at the limit of steady-state cornering force in a Lotus on the road, then you're driving a little bit dangerously IMO...The motorway corner from the M25 east to the A21 south is pretty much the only place on the road where I can really notice the difference in steady-state lateral G on different tyres. And given that corner tightens up and has a surface change, it's probably a bit reckless.
What's more interesting is agility, being able to flick from a high cornering force in one direction to another. The Lotuses deliver in spades here, mostly due to light weight.
Sam_68 said:
...and short wheelbase with combined with low polar moment, which are also exactly the reasons why you need to be quick to catch it when it does break away, and foolish to push it right to the limit of grip on public roads.to get to the limits of grip on the road, you have to be doing something stupid.
Excellent advice here from Sam and Scuffers. I had been thinking more on a theoretical level. Personally I find road driving in an elise a chore anyway. I doubt I test 50% of the car's limits on the road.
On the other hand, given my abundance of driving talent (not) if I get to within 70% of the limits on track, I'd probably end up in a tyre wall.
On the other hand, given my abundance of driving talent (not) if I get to within 70% of the limits on track, I'd probably end up in a tyre wall.
shangani said:
Excellent advice here from Sam and Scuffers. I had been thinking more on a theoretical level. Personally I find road driving in an elise a chore anyway. I doubt I test 50% of the car's limits on the road.
On the other hand, given my abundance of driving talent (not) if I get to within 70% of the limits on track, I'd probably end up in a tyre wall.
Funny that, since I love driving mine on the road. Motorways are boring, but a decent B road is great fun.On the other hand, given my abundance of driving talent (not) if I get to within 70% of the limits on track, I'd probably end up in a tyre wall.
On track, you're usually pushing hard and corner speeds are higher. I don't usually get big drift angles on track (unless I've got a corner badly wrong) but you can mess about at low speeds on the road (e.g. empty roundabout in the wet, etc.) - of course when the tyres slip in this way it's nothing to do with lateral G, but mostly grip being overcome by power.
Not that I recommend practising sliding an Elise about on the public road, of course
cyberface said:
The motorway corner from the M25 east to the A21 south is pretty much the only place on the road where I can really notice the difference in steady-state lateral G on different tyres. And given that corner tightens up and has a surface change, it's probably a bit reckless.
What's more interesting is agility, being able to flick from a high cornering force in one direction to another. The Lotuses deliver in spades here, mostly due to light weight.
I know the corner well, and on warm 888's you can do what most would regard as silly speeds all the way round. In a well set-up car that surface change doesn't matter... unless it's wet, in which case it can throw you sideways if you're not careful. Best not done (more than once) really.What's more interesting is agility, being able to flick from a high cornering force in one direction to another. The Lotuses deliver in spades here, mostly due to light weight.
Even on decent Advans, that corner can be done exceptionally quickly in an Elise, and with confidence.
You're very right about the direction change. Even though it might not exert a very high "G" force, it certainly feels like a very hard 'lean' on the cars ability though at many times.
So what then would be the setup for the out-and-out fastest cornering elise (not including non-road tyres/slicks)
The reason I ask is that much is made about power upgrades but then a standard elise will "have 'em in the corners", so how would one capitalise on that aspect, or does the board feel Lotus has gone for the optimum setup already?
The reason I ask is that much is made about power upgrades but then a standard elise will "have 'em in the corners", so how would one capitalise on that aspect, or does the board feel Lotus has gone for the optimum setup already?
M030ef00 said:
So what then would be the setup for the out-and-out fastest cornering elise (not including non-road tyres/slicks)
The reason I ask is that much is made about power upgrades but then a standard elise will "have 'em in the corners", so how would one capitalise on that aspect, or does the board feel Lotus has gone for the optimum setup already?
that rather depends on the surface your working with.The reason I ask is that much is made about power upgrades but then a standard elise will "have 'em in the corners", so how would one capitalise on that aspect, or does the board feel Lotus has gone for the optimum setup already?
at the end of the day, it's more to do with feel than outright grip (more so on the road as I would hope you are never that close to the grip limits).
Scuffers said:
M030ef00 said:
So what then would be the setup for the out-and-out fastest cornering elise (not including non-road tyres/slicks)
The reason I ask is that much is made about power upgrades but then a standard elise will "have 'em in the corners", so how would one capitalise on that aspect, or does the board feel Lotus has gone for the optimum setup already?
that rather depends on the surface your working with.The reason I ask is that much is made about power upgrades but then a standard elise will "have 'em in the corners", so how would one capitalise on that aspect, or does the board feel Lotus has gone for the optimum setup already?
at the end of the day, it's more to do with feel than outright grip (more so on the road as I would hope you are never that close to the grip limits).
) but there's a limit to the aggressiveness of the geo vs. keeping the car usable to drive on-road (for *most* A&B roads let's say). I had a fair bit of camber on the last S1 I had (I think the front uprights had been machined a bit by Guglielmi's), and on the S2 it was right at the limit. Both tramlined a fair bit when the road was rutted. Is it the case that there is a limit to *useful* camber for mainly on-road driving as such, before you make the car less fun to use.On a very smooth track I presume that an optimum set-up would go pretty hardcore on this front and really lean on the suspension and tyres in hard cornering (per most race cars).
I'm a technical numptie on this as you can probably tell, but it'd be interesting to hear thoughts on how far is *far enough* for the average mainly road-biased car.
M030ef00 said:
So what then would be the setup for the out-and-out fastest cornering elise (not including non-road tyres/slicks)
The reason I ask is that much is made about power upgrades but then a standard elise will "have 'em in the corners", so how would one capitalise on that aspect, or does the board feel Lotus has gone for the optimum setup already?
...the setup which correctly works the tyre in the most optimum way over its entire width. This will vary according to tyre design, compound and road conditions.The reason I ask is that much is made about power upgrades but then a standard elise will "have 'em in the corners", so how would one capitalise on that aspect, or does the board feel Lotus has gone for the optimum setup already?
Camber for a track car is usually set with the aid of a tyre pyrometer, rather than a 'bolt -3 degree top plates on' approach. Without a tyre temp guage, you're p1ssing in the wind if you want to set your car up properly on track.
S Works said:
Scuffers said:
M030ef00 said:
So what then would be the setup for the out-and-out fastest cornering elise (not including non-road tyres/slicks)
The reason I ask is that much is made about power upgrades but then a standard elise will "have 'em in the corners", so how would one capitalise on that aspect, or does the board feel Lotus has gone for the optimum setup already?
that rather depends on the surface your working with.The reason I ask is that much is made about power upgrades but then a standard elise will "have 'em in the corners", so how would one capitalise on that aspect, or does the board feel Lotus has gone for the optimum setup already?
at the end of the day, it's more to do with feel than outright grip (more so on the road as I would hope you are never that close to the grip limits).
) but there's a limit to the aggressiveness of the geo vs. keeping the car usable to drive on-road (for *most* A&B roads let's say). I had a fair bit of camber on the last S1 I had (I think the front uprights had been machined a bit by Guglielmi's), and on the S2 it was right at the limit. Both tramlined a fair bit when the road was rutted. Is it the case that there is a limit to *useful* camber for mainly on-road driving as such, before you make the car less fun to use.On a very smooth track I presume that an optimum set-up would go pretty hardcore on this front and really lean on the suspension and tyres in hard cornering (per most race cars).
I'm a technical numptie on this as you can probably tell, but it'd be interesting to hear thoughts on how far is *far enough* for the average mainly road-biased car.
In the longer term I'm getting a second set of wheels to fit with track tyres and then thinking of chasnging the camber at the track: if the bolts come out of the plinths/steering arms easily it should be do-able fairly quickly. Obviously toe is another factor in tyre wear but I won't be messing with that, too bloody difficult.
I don't know if just changing the camber will help tyre life but I'll have a play anyway.
Does anyone know if I can just replace the horrible hex socket type bolts that hold the plinths and hubs in place with anything else? I've just chewed one up trying to get it out!
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