19 replies to this topic

[rodlamas]

Hi all, simple question.

 

I wonder what kind of speed this F1 2014 cars can do.

 

For instance. Magnussen was at 318kph in 8th gear @ 11,200rpm. Assuming they can rev the engine until 15,000 rpm and given that we know the rear tire spec, but we don't know the gear ratios themselves, how can we calculate what would be Magnussen's top speed at 15,000rpm on the same gear?

 

Thanks!

[Lennat]

You don't need to know the specs.

 

318/11,200=0.0283928571

 

0.0283928571X15,000=425.8928565

 

The only conclusion to be drawn from this is that they won't ever reach 15k on the final gear, ever. 

[alexbiker]

They weren't using 15k very much in any gear - the fuel flow limit doesn't allow it to be very useful.

 

Monza might be interesting, given the lower drag these cars seems to have, and the torque advantage out of the chicanes.

[rodlamas]

They weren't using 15k very much in any gear - the fuel flow limit doesn't allow it to be very useful.

 

Monza might be interesting, given the lower drag these cars seems to have, and the torque advantage out of the chicanes.

I think we will get a preview in Malaysia with the 2 1+ km straights.

[Tenmantaylor]

Just to put things into perspective the fastest lap in any session was still over 3s slower than in 2013 even though they were almost 10kmh faster in the trap. Just shows how insignificant top speed is to lap time on the average F1 track.

 

Have to admit though, when F1 cars don't hit 200mph/320kmh on a straight it does make my soul weep slightly.

[munks]

You don't need to know the specs.

 

318/11,200=0.0283928571

 

0.0283928571X15,000=425.8928565

 

The only conclusion to be drawn from this is that they won't ever reach 15k on the final gear, ever. 

 

Yeah, I imagine the horsepower vs. drag curves will cross well before then.

[MatsNorway]

And that is really good. It was pure pain to see them hit the revlimiter and not get past despite them having the momentum in the passing initially.

[Ross Stonefeld]

You don't need to know the specs.

 

318/11,200=0.0283928571

 

0.0283928571X15,000=425.8928565

 

The only conclusion to be drawn from this is that they won't ever reach 15k on the final gear, ever. 

 

Given they have fixed ratios for the season, why would you gear the car for speeds the car can't reach (tracks, aero) and an RPM you'll never use? Why not pull the gear spacing back into the real world envelope?

[MatsNorway]

You gear it for maximum power. the Torque vs Power debate is finally dead! weeee!

[desmo]

I actually think the fixed ratios this year are a cool idea. It should definitely favor certain teams on certain tracks. Imagine if aero packages were fixed for the season. You might even see a midfield team win Monaco or Monza.

[Greg Locock]

On a somewhat related note I put this together, it shows a rational (ie not rules based, and it assumes a balanced design in every respect) approach to the first baby steps when setting up a downforce car. The feasibility limits are based on some data from Katz and a very simple F1 model based on the ferrari 2000 book.

 

http://www.mediafire...s_car_aero2.png

 

Basically the F1 curve starts with a cd disadvantage compared with the absolute limit due to the open wheels, and its incremental L/D is worse even for the most efficient part of the curve. Once you run out of floorpan then the less efficient wings come into play. The particular design shown is a generic f1 car

Edited by Greg Locock, 24 March 2014 - 19:07.

[Fat Boy]

You gear it for maximum power. the Torque vs Power debate is finally dead! weeee!

 

Gearing is for minimum average lap time with a limited fuel supply. It's probably not spending time anywhere near peak power in the higher gears.

[gruntguru]

The power would be fairly flat from 10,500 to 15,000 rpm due to flat fuel delivery. Any variation in power across that band will be due to variations in engine efficiency. Best efficiency and therefore peak power will probably be close to 10,500 and the gearing was probably chosen to allow revs of 10,000 - 12,000 on the straight at all tracks.

Edited by gruntguru, 24 March 2014 - 23:29.

[MatsNorway]

FB; No way they would gear if for two tracks where fuel limit is an issue. Its a non topic. On these two tracks that they do have to worry about the fuel they would probably shortshift like before.

 

GG: Setting the gears would mean that at least the big teams would take out certain tracks like Monza and Monaco in the evaluation. Its a too big a sacrifice for the other tracks.

Edited by MatsNorway, 25 March 2014 - 11:11.

[Canuck]

One of the things I like about this forum is watching the arm-chair quarterbacks (IE me) arguing with those that actually "do" for a living.  It helps me keep my mouth shut...sometimes.

[gruntguru]

GG: Setting the gears would mean that at least the big teams would take out certain tracks like Monza and Monaco in the evaluation. Its a too big a sacrifice for the other tracks.

Not sure what you are saying here Mats but IMO there is no way they would select gears that would seriously compromise top speed at any track. When the hammer is down, the end of the straight is still one of the best overtaking opportunities.

[alexbiker]

Especially in the DRS era.  You are everyone's bitch if they simply drive past whilst you're bouncing off the rev limiter when you try to pay it back.  Except if you're Red Bull and Vettel and you're so far ahead no-one gets within DRS activation.

 

There are after all no points for lap times.

[gruntguru]

Another thing to consider is that these are near constant-power engines over 33% of their rpm range. This means that gearbox ratios do not have to be very close to achieve best acceleration. For example a constant spacing of 1.2 (20% rpm drop) throughout the box would allow shifting at 11,700 and only dropping to 9,750 in the next gear. The 1.2 spacing would also mean top speeds (at 15,000 rpm) in the gears of 119, 142, 171, 205, 246, 295, 354, 425 kph, the point being that 119 in first gear is pretty low by F1 standards so no problem getting off the line.

 

It is most probable that 1st gear would be somewhat taller - and - the ratio spread would reduce as you go up in gears eg 133, 172, 215, 262, 309, 354, 394, 425 - giving a finer range of top speeds for different tracks.

[MatsNorway]

Alex: No one is hitting the rpm limit in eight this year i am certain

 

GG: I tried to say that believe you have to make a compromise. One track is not a priority. (say Monaco) there you will run with whatever you have anyway, say with the spacing you posted above.

 

Its probably some driver input in there also as they might not like them stacked too close low down. Gear chances upsets the car?

[Nemo1965]

I have to say that gearring always confuses me. For instance: I don't even know what advantage a 7-speed gearbox has over a 6-speed at Monaco... At tracks like that: would it not be more handy to have less gears? My idea is: the more gears, the smaller steps between the gears are. Which means higher revs, more wheelspin...