RWD - FWD - LSD - No of Cyls. Can You Really Tell?

[CABC]

RobM77 said:

That's not quite true though is it? Plenty of road cars are quicker in terms of lap times and top speed. I presume you mean purely in terms of acceleration?

Let's not be too pedantic Rob yes acceleration (mostly), and i thought the context was road cars in that portion of the thread. But it'll take a very expensive car to get close to an R1. I would discount anything lightweight as he may as well take the bike! In the 'broadest mainstream' selection of cars he'll take his bike for raw thrills, so any heavy fast grippy car won't impress too much (135i as an example).

[RobM77]

CABC said:

RobM77 said:

That's not quite true though is it? Plenty of road cars are quicker in terms of lap times and top speed. I presume you mean purely in terms of acceleration?

Let's not be too pedantic Rob yes acceleration (mostly), and i thought the context was road cars in that portion of the thread. But it'll take a very expensive car to get close to an R1. I would discount anything lightweight as he may as well take the bike! In the 'broadest mainstream' selection of cars he'll take his bike for raw thrills, so any heavy fast grippy car won't impress too much (135i as an example).

Sorry, it had to be said! If we're talking big heavy comfy cars with four seats though, then yes, you're quite right.

Back to the point though, yes I'm sure the GT86 is indeed the answer to many people's car needs, especially on our increasingly crowded and speed limit infested roads. I suspect there's a similar argument for an R6 or even a 250 or 400 - I know a guy I used to work with ran a CBR400 and rode it like a nutter and said he preferred it to the faster bikes 99% of the time because it was lighter and more nimble. With cars at least, you can't add a capability to go really fast without compromising weight and other things, so if it's a capability you rarely use, you carry those compromises around for no net benefit.

[CABC]

RobM77 said:

With cars at least, you can't add a capability to go really fast without compromising weight and other things, so if it's a capability you rarely use, you carry those compromises around for no net benefit.

haven't driven the latest MX5 yet, but i suspect the best car could well be a 1.5.
i said this in another thread and that the lack of lsd was not so much of an issue in a low powered car not on track (aka public road!). the gods appeared and it seems it's LSD all day everyday. i don't think so.

[RobM77]

CABC said:

RobM77 said:

With cars at least, you can't add a capability to go really fast without compromising weight and other things, so if it's a capability you rarely use, you carry those compromises around for no net benefit.

haven't driven the latest MX5 yet, but i suspect the best car could well be a 1.5.
i said this in another thread and that the lack of lsd was not so much of an issue in a low powered car not on track (aka public road!). the gods appeared and it seems it's LSD all day everyday. i don't think so.

I certainly do view an LSD as one of those compromises, due to the effect they have on handling.

[SirSquidalot]

Fuel octane I think you can feel a subtle difference, it’s not night and day though. This is most likely a placebo for 90% of people.

FWD/RWD/FWD – Very easy to tell imo, even just manoeuvring feels slightly different to me. FWD feels more of a pull, RWD feels more of a push.

LSD/No LSD – Without pushing hard its not that easy, my mx5 has an LSD but you only really feel it when pushing close to the limit. Nailing it out of tight corners/roundabouts its where you tend to feel it most. Also makes it very easy to slide!

No of Cyls - Depends, most newer cars seem to be very smooth so it is harder to tell. An older 4 pot and an older 6 pot though, very easy to tell apart.

Edited by SirSquidalot on Tuesday 18th October 10:37

[CABC]

RobM77 said:

I certainly do view an LSD as one of those compromises, due to the effect they have on handling.

Compromise? Not sure of your meaning Rob.

I love LSDs. But "if" the 1.5 mx5 was sweeter and better balanced then the lack of lsd is a compromise I'd consider, especially as on a public road you'd enjoy the balance but not miss traction out the corners so much.

[BugLebowski]

Let me be the first to make a confession then; I drove a rear engined (turbocharged), rear wheel drive for four days during the summer without realising it. The only thing out of the ordinary that I noticed was that it had a really small turning circle. I guess I should relinquish my PH membership

I give you the Porsche 911 GT2 Renault Twingo:



I would suggest that all other things being equal, the difference is not all that obvious in 99% of driving.

[GravelBen]

CABC said:

I said this in another thread and that the lack of lsd was not so much of an issue in a low powered car not on track (aka public road!). the gods appeared and it seems it's LSD all day everyday. i don't think so.

Its an interesting one, when I had a Mk1 MX5 I think I felt the lack of LSD more often on the road than on track. I'm sure it wouldn't have made much difference to performance, it was just that the tendency to spin an unloaded inside wheel at low speed was annoying at times. Having said that I never drove one with a decent LSD, maybe I would have noticed some other downside if I had.

Like many handling characteristics I guess its often more about personal preference than being objectively better or worse. I preferred the Mk1 MX5 to the Mk1 MR2 and bought an MX5, a good mate ranked them the other way around and bought an MR2. Neither of us thought the other was wrong, just personal taste. Often that gets missed on the internet though!

Edited by GravelBen on Tuesday 18th October 10:40

[culpz]

BugLebowski said:

Let me be the first to make a confession then; I drove a rear engined (turbocharged), rear wheel drive for four days during the summer without realising it. The only thing out of the ordinary that I noticed was that it had a really small turning circle. I guess I should relinquish my PH membership

I give you the Porsche 911 GT2 Renault Twingo:



I would suggest that all other things being equal, the difference is not all that obvious in 99% of driving.

Careful! Remember that this is PH. I got scorned the other week after saying that the most recent RWD car i drove, a hired BMW 118i, didn't feel at all rear-driven. I said that because it honestly didn't apart from one brief moment when one of the rear wheels span slightly after pulling away from a wet and grassy bit of land.

I do like those Twingos i must say. Petty amazing that they went with a re-engined and re-driven formula. I can imagine that it really didn't have anything to give it away though, both in terms of looks and feel. What did you think of it as a whole?

[CABC]

GravelBen said:

Its an interesting one, when I had a Mk1 MX5 I think I felt the lack of LSD more often on the road than on track. I'm sure it wouldn't have made much difference to performance, it was just that the tendency to spin an unloaded inside wheel at low speed was annoying at times. Having said that I never drove one with a decent LSD, maybe I would have noticed some other downside if I had.

Like many handling characteristics I guess its often more about personal preference than being objectively better or worse. I preferred the Mk1 MX5 to the Mk1 MR2 and bought an MX5, a good mate ranked them the other way around and bought an MR2. Neither of us thought the other was wrong, just personal taste. Often that gets missed on the internet though!

Edited by GravelBen on Tuesday 18th October 10:40

With less power, you might feel the LSD less on track as you're carrying more speed through the corner and so not losing the inside wheel. Different in a 200hp Caterham obviously.
On the road it could be that with more cautious cornering but an early boot full the LSD would help.
I'm not championing no LSD, but enjoy a good blat on my favourite roads that I know well . On today's roads I can see hustling a balanced 1.5 could be great fun. The 2l is heavier, lees sweet and obviously more expensive. Price does come into it otherwise it'll be a 458 Speciale.

Btw the Twingo is a packaging solution and will have had its rwd 'characteristics' dialled out for shopping duties. Goes back to the point often made here that rwd does not necessarily make a good car.

[RobM77]

CABC said:

RobM77 said:

I certainly do view an LSD as one of those compromises, due to the effect they have on handling.

Compromise? Not sure of your meaning Rob.

I find that they have a detrimental effect on handling; causing understeer in the middle phases of a bend and in extremis, they can cause unwanted and unpredictable oversteer on corner exit. I've just never got on with them. Maybe I just need to learn to drive with one through having more practise. 2017 will give me that practise in a new car I've just bought, so maybe I should report back this time next year!

[CABC]

RobM77 said:

I find that they have a detrimental effect on handling; causing understeer in the middle phases of a bend and in extremis, they can cause unwanted and unpredictable oversteer on corner exit. I've just never got on with them. Maybe I just need to learn to drive with one through having more practise. 2017 will give me that practise in a new car I've just bought, so maybe I should report back this time next year!

Ah right.
Well more traction at the back., more push..
I guess the best LSD experience would come from a manufacturer's car in that someone like Matt Becker will have tuned the suspension and tyres to suit. Just retro fitting one could unsettle everything like you say. Tricky thing modifying cars.

[RobM77]

CABC said:

Ah right.
Well more traction at the back., more push..
I guess the best LSD experience would come from a manufacturer's car in that someone like Matt Becker will have tuned the suspension and tyres to suit. Just retro fitting one could unsettle everything like you say. Tricky thing modifying cars.

They cause understeer by resisting the differential rotation of the driven wheels, which is something that needs to happen for a car to go around a corner.

As you say though, any modification does have to be properly set up in context. However, my comments come from driving cars with the LSD fitted as standard.

[Toltec]

BugLebowski said:

Let me be the first to make a confession then; I drove a rear engined (turbocharged), rear wheel drive for four days during the summer without realising it. The only thing out of the ordinary that I noticed was that it had a really small turning circle. I guess I should relinquish my PH membership

I give you the Porsche 911 GT2 Renault Twingo:



I would suggest that all other things being equal, the difference is not all that obvious in 99% of driving.

I find mid/rear engines make the steering feel even purer, the front wheels really are just for steering, if that makes sense? Braking also feels different, you have to load up the front before braking hard or you can easily lock the front wheels.

My experience is limited to three mr cars though and none were the Twingo so the setup may make it less obvious.

[CABC]

RobM77 said:

They cause understeer by resisting the differential rotation of the driven wheels, which is something that needs to happen for a car to go around a corner.

at this point, hands up, i'm at the limit of my knowledge and experience.
i see what you say. So the question i have is when do these varying dynamics kick in?

low speed - no issues
under high throttle (exit): - the diff provides more traction and drive. so long as the front can hold then everything is great. fabulous.
too much drive an you might get understeer, often the case in std road cars. gt86 does this.

middling throttle, say mid-corner - not really asking the diff to limit slip as you're balanced. but the diff's resistance prevents rotation and the front can't overcome this as easily as with an open diff.
at this point the diff is creating unwanted inertia?

is this it?

[Limpet]

Fuel octane - depends on the car, but I defy anyone to tell what quality of petrol is in a car without a few hundred miles of familiarity in that car with both fuel types

FWD/RWD/FWD – Bimbling about in the dry - no difference. No modern car has enough steering feel to "feel" the power going through the wheels (or not) under normal driving conditions. Throw wet conditions and/or harder acceleration, particularly off roundabouts and out of junctions into the mix, and you can tell quite quickly. Plus of course mashing the throttle to the floor to kill oversteer in a FWD car will put you off the road in the same situation in a RWD one. But in normal, gentle driving, it is irrelevant. The first thing I noticed between the X-Drive and RWD F30 was the crappy turning circle on the X-Drive. Until you start hoofing the throttle out of tight corners, they feel virtually identical otherwise.

LSD/No LSD – A lot of power out of a tight corner will give this away, but until then, I couldn't tell.

No of Cyls - 3, 4, 5, 6 and 8 very easy, although soundproofing on modern vehicles means you often get no noise at all unless you are really working the engine hard. Sixes in particular always feel creamy smooth to me, compared to fours.

Edited by Limpet on Tuesday 18th October 12:18

[bennyboysvuk]

RobM77 said:

CABC said:

bennyboysvuk said:

Right, I'm off to buy a GT86.

i think you'd understand the 86 more than most. all about feel and connection. no car will compete in pace with your R1, best thing a car can do is be delicate, adjustable and feelsome.

That's not quite true though is it? Plenty of road cars are quicker in terms of lap times and top speed. I presume you mean purely in terms of acceleration?

Thanks CABC. I've become more and more fascinated by the GT86, but I still might go the other way and get an old 911, just for the NVH and experience.

Rob, it's quite true. Slightly tongue-in-cheek, but on the road the very fastest cars cannot fit into the gaps that bikes can, not even the Twizy.

[BugLebowski]

culpz said:

Careful! Remember that this is PH. I got scorned the other week after saying that the most recent RWD car i drove, a hired BMW 118i, didn't feel at all rear-driven. I said that because it honestly didn't apart from one brief moment when one of the rear wheels span slightly after pulling away from a wet and grassy bit of land.

I do like those Twingos i must say. Petty amazing that they went with a re-engined and re-driven formula. I can imagine that it really didn't have anything to give it away though, both in terms of looks and feel. What did you think of it as a whole?

It was a decent little city car, light and nippy. I don't have any use for a small city car but if I did, I would certainly consider it. You can tell Renault tried hard to make it drive like any other car in the same class.

I'm fairly certain that there are a percentage of BMW drivers that have no idea which wheels are driven on their cars. At least until the first sign of snow

[bob-lad]

CABC said:

DoubleD said:

It's only car bores who care what wheels are driven and what engine is powering it. Non car bores care about their own dull things, they are probably amazed that people don't know about this that or the other of their hobby.

yep, but this is a car bore site?

Agreed, but the original question was about "most people" not specifically most PHers.

I think most people don't care about any of it and just don't want to get wet going to work or shopping, so they buy whatever they can afford, be it saloon or estate depending on dog:kid ratio, in a colour their wife likes.

[M4cruiser]

CharlesdeGaulle said:

And as for cylinders, can the average driver honestly tell how many cylinders are under the bonnet: 3, 4, 5 or 6?

Yes I can - there are loads of 3-cylinder cars now, compared with say 10 years ago, and most of them have awful engines.

You can make a direct comparison with a Fiesta from the last 2 years or so, just try a 1.0 then a 1.25, and the difference is blindingly obvious. The 1.0 wobbles and vibrates and does my head in. The 1.25 is a dream in comparison.

Same with VW Polos now, and Corsas. The 1.4 Corsa is so much smoother than the 1.0.