Ondrejko just spotted that the UF weights the same with or without roof... Was this done on purpose? Before THE patch, the topless version was lighter...

I just got here because I saw "topless"

The roofless version would (IRL) need extra "chassis" strength to keep chassis flex low. I think real topless cars usually weigh more.

So yes, it has changed, and it is more realistic.

Noticed this today too, I think its good. Flexing of the body isnt modelled so the roofles version doesnt have the disadvantage, it was ligter and still stiff as the version with roof so it was unrealistic. And I never liked that roofless version, it looks so silly to have 20 of those enywhere.

A very good move by the devs. IRL a topless Mini would never be used for racing due to the lack of chassis stiffness.

Why the stiffness is so important in racing?

Quote from himself :

Why the stiffness is so important in racing?

stiffness keeps the wheels on the ground

when you setup your car you adjust suspension springs etc

if the body is flexing you are introducing a seperate movement that affects the handling of the car. generally speaking the aim is to have the chassis or monoque as stiff as possible to remove this variable.

in karting, where there is no suspension in the conventional sense, the flex of the kart is adjusted to provide a suspension effect though you'd probably need becky rose or similar to give you more accurate info on this

The roof should be removed from the LX6. As it is supposed to be a race tuned version. In LX4 it's ok of course.

Quote from deggis :

The roof should be removed from the LX6. As it is supposed to be a race tuned version. In LX4 it's ok of course.

I for one would like to see LX6 with hard roof illepall
I'll probably gonna see it only in some edited render

Now Im wondering whether the roof still affects the topspeed or not

Quote from tinvek :

when you setup your car you adjust suspension springs etc

if the body is flexing you are introducing a seperate movement that affects the handling of the car. generally speaking the aim is to have the chassis or monoque as stiff as possible to remove this variable.

in karting, where there is no suspension in the conventional sense, the flex of the kart is adjusted to provide a suspension effect though you'd probably need becky rose or similar to give you more accurate info on this

When my family decided to buy a convertible for my mom several years ago, we also tested a Chrysler LeBaron, just for fun. The chassis flexed so much that you could not open a door when one wheel was on the pedestrian sidewalk and the other 3 on the street! illepall
We bought a BMW e30 320i convertible instead.
The convertible version of this car is several kilogramms heavier then the sedan, because the chassis has been enforced so much.

Quote from ORION :

Now Im wondering whether the roof still affects the topspeed or not

Doesn't seem to. Tried both versions on BL1 and they both top out at 155km/h with some gear to spare.

At low top speeds like those, a roof wouldn't really effect it that much if any, but in my opinion the car should be made heavier if it doesnt have a roof rather than the same.

At 155km/h about 25% of the engine power goes towards rolling resistance and about 75% towards aerodynamic drag. I wouldn't be surprised if the difference between roof and no roof was around 5mph. Thing is though, nobody would be using the open roof car if it was heavier (or just as heavy) and less aerodynamic.

From experience with Morgans IRL:

Roof down + aero screens is the fastest combination.

If full windscreens are forced then a canvas or fibre glass top is best.

Windscreens with the hood down are slowest.

Quote from RedStarArmy :

At low top speeds like those, a roof wouldn't really effect it that much if any, but in my opinion the car should be made heavier if it doesnt have a roof rather than the same.

Total weight difference: about a kilo of fabric :doh:

iirc the (bmw) Mini convertible is actually heavier than the equivalent version with a roof

the 'rari F430 maybe in that category too...

Quote from bal00 :

At 155km/h about 25% of the engine power goes towards rolling resistance and about 75% towards aerodynamic drag.

I tested and both versions max out at 161km/h for me. According to my figures though, the split is 86% / 14%, since the car is quite light. Not a bad guess though.

Quote from bal00 :

Thing is though, nobody would be using the open roof car if it was heavier (or just as heavy) and less aerodynamic.

This is exactly why they don't race them IRL. Although it would mean making the topless version rather useless, it would probably be the most realistic thing to do.

However, I always have a lot of quite slow fun with these machines, and I couldn't really be bothered with it.

Quote from ajp71 :

From experience with Morgans IRL:

Roof down + aero screens is the fastest combination.
If full windscreens are forced then a canvas or fibre glass top is best.
Windscreens with the hood down are slowest.

Total weight difference: about a kilo of fabric

I think this is true for a morgan since it's constructed already as a cabrio. However with a car like the UF1 -or most road cars with a cabrio version for that matter- they have to chop the roof of, but because the roof was a important part for structural integrity they have to strengthen(read add weight) it on the chassis.

Quote from ajp71 :

Total weight difference: about a kilo of fabric :doh:

That's not how it works out in real life though.

No roof = lots of reinforcement. Without frame reinforcement you'll end up with a wet noodle for a chassis, which of course is bad. So most convertables weight quite a bit more because of the extra reinforcement.

Quote from TravisS :

That's not how it works out in real life though.

No roof = lots of reinforcement. Without frame reinforcement you'll end up with a wet noodle for a chassis, which of course is bad. So most convertables weight quite a bit more because of the extra reinforcement.

No you've totally missed the point of my post. I've been argueeing for ages that the UF1 convertable is totally unrealistic due to the lack of structural stiffness simulation.

In the example I'm talking about (Morgans - http://www.morgan-motor.co.uk/) the cars are constructed using a very old system of a ladder frame chassis with bodywork attached via an ash frame. The cars have a windscreen which is designed to be removed and easilly replaced with aeroscreens. The roof is only made of canvas and offers no additional stiffness sometimes racing Morgans are fitted with fibreglass hard tops, these also offer no sturctural benefit and are only used in series which don't allow aeroscreens.

Scawen mentioned around the time that S2 came out that he decided not to model a difference in aerodynamics with the LX cars roof up/down as he felt it would be a shame for people to end up racing them roof up for extra speed, as there is the option to have them roof down. So, it was a conscious decision not to include any differences like that. I believe it's the same with the UF. I'm glad it's been done that way, because it would be a shame to see everyone racing roof up for the aero advantage. Especially when they mostly race in real life without roofs.

Quote from Michael Denham :

I'm glad it's been done that way, because it would be a shame to see everyone racing roof up for the aero advantage. Especially when they mostly race in real life without roofs.

Hope you didn't mean to say Minis race IRL with open roofs

Before the recent patch's the roofed version had a higher top speed and less acceleration.. or so it seemed anyway. The convertible would corner way better too.