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Isn't he rear supposed to roll more than the front anyways?

The rear is (more or less) rigidly connected to the front... by a carbon tub. So how would the rear be able to roll more than the front?

Jersey Tom wrote:

kilcoo316 wrote:

Jersey Tom wrote:1) There's nothing inherently wrong with body roll

From an aerodynamics perspective, it is... undesirable.

But you're always going to have it.. and springing the car solid is gonna do more harm than good. There's ways of making sprung mass roll work for you.

Bottom line, I wouldn't be too concerned if the McLaren rolls more than other cars. Big deal.[/quote]

The bid deal is this, if the body roll is more than intended the inside rear tyre gets unloaded and will spin up when the power is applied. So this gives two problems, 1. tyre wear and 2. time spent off throttle.

If you reduce the body roll you can get on the power earlier. so if it means you are off the gas for 1/10s longer than your rival that = ~1.2s (12 corners) per lap.

Excess Body Roll = Big Deal.

McMacca wrote:Excess Body Roll = Big Deal.

True

McMacca wrote:The bid deal is this, if the body roll is more than intended the inside rear tyre gets unloaded and will spin up when the power is applied. So this gives two problems, 1. tyre wear and 2. time spent off throttle.

If you reduce the body roll you can get on the power earlier.

Not true

Body roll doesn't directly cause your inside wheel to unload. Thats load transfer. Load transfer causes body roll not the other way around.

Back on topic - roll rates are a pretty fundamental thing. doubt Mclaren would have stuffed them up.

Exactly, they've set a few cars up in the past and the body roll is something I'm happy that they'll sort out.

i think at that particular corner the roll is coming more from the deflection in the tyres than it is from suspension. look closely. I think the anti-roll systems are doing their job just finethankyouverymuch.

Today Hamilton complained about the car bottoming out a lot. It's not like they suddenly have tremendous amounts of downforce? Then it's suspension.

modbaraban wrote:Today Hamilton complained about the car bottoming out a lot. It's not like they suddenly have tremendous amounts of downforce? Then it's suspension.

Or the tyre pressures. I'm sure it's just a case of them wanting to run as low as possible to maximise the effectiveness of the diffuser and front wing.

Seems to me that they are having massive problems bringing the tires up to temp(& pressure). That may be why they are bottoming so bad.

Kovi did better in FP1 than in 2, again maybe a temp thing as track temps were going down later in the day.

Theres more to it than meets the eye, IF you have low rear end grip, what do you do? Wind on some more rear wing?

Q: You were very quick on the straight as well, fastest by about two or three kpm. Does that suggest you are not running a lot of downforce?
LH: No, it just means we have got a good Mercedes Benz engine.

Your struggling with the car bottoming out?

Q: Lewis, we heard you say that the car was bottoming all the time and was really very difficult to drive.
LH: Yeah, it is a very bumpy track, so I think at the time we were just a bit too low. That’s what happens when you are on heavier fuel, so we will make some changes to make sure that doesn’t happen anymore.

So it seems that this 'SLOW' McLaren is runnig fat with fuel and is the quickest thing in a straight line?

Anybody else confused...........?

fuel level (weight) doesnt have much to do with top speed, provided the straight is long enuff.

ISLAMATRON wrote:fuel level (weight) doesnt have much to do with top speed, provided the straight is long enuff.

Bit it does reduce lap times.....

Tim.Wright wrote:Back on topic - roll rates are a pretty fundamental thing. doubt Mclaren would have stuffed them up.

Exactly. In the grand scheme of things, reducing body roll (by itself) is EASY. Thus my original comment that whatever roll is there, is there for a reason.

ISLAMATRON wrote:Seems to me that they are having massive problems bringing the tires up to temp(& pressure). That may be why they are bottoming so bad.

Kovi did better in FP1 than in 2, again maybe a temp thing as track temps were going down later in the day.

It is quite possible. If that is symptomatic of a problem with the car rather than a setup / settings issue (remember they've changed so much on the car now that they probably don't know that much about dialing it in to a circuit) then it could take them a while to resolve.

kilcoo316 wrote:
From an aerodynamics perspective, it is... undesirable.

Actually, that is something that I always wondered about. Especially with some roll the downforce on the front wing will point towards the turn direction, and thus assist the turn. The contribution of rear wing on the overall downforce is much smaller, and the downforce from the airflow under the car should not change direction (thus remain vertical) with the roll.

So, getting some roll on an F1 car should be advantageous. Any ideas?