Kart Racing Pro Official Forum

General => General Discussion => Topic started by: Nathan Dunnett on May 29, 2013, 08:00:02 AM

Title: Aero drag
Post by: Nathan Dunnett on May 29, 2013, 08:00:02 AM
Is it just me or does it seem far too excessive? I didn't realise until I made up engine files for a KT100J based off a real dyno sheet from one of our own engines, and I could barely go over 80 km/h at Lonato. I even made sure it permanently had perfect carburetion and optimum temperatures so that I was getting full power from the engine. Using the same gearing in real life at a track with a shorter straight and a tighter corner leading on to the straight this engine easily does 90-92 km/h without draft or ducking. I had to give the engine way more power than what it realistically has to get almost normal speeds out of it, and then if I tried to duck I would get like an extra 6-7 km/h whereas in real life it's more like 1-2 km/h tops if you're lucky and there is a head wind. Just by ducking I was gaining 1.5 seconds per lap at Lonato which is completely ridiculous for low speeds in good conditions. I haven't been on track with another kart that wasn't blinking and warping all over the place yet but I imagine the draft effect is massive, can anyone confirm this?
Title: Re: Aero drag
Post by: PiBoSo on May 29, 2013, 11:40:23 AM
Aero drag is taken from real life data.
How much power does the KT100J have? The mini kart can easily go over 95 km/h at Lonato with less than 13hp.
Title: Re: Aero drag
Post by: Nathan Dunnett on May 29, 2013, 01:16:00 PM
11.5 hp peak at around 7500 RPM, 8.8 hp at around 11000 RPM. In real life we would use 11/71 gearing with a rear tyre circumference of approx 865mm and rev to 11200-11400 RPM at the end of a mostly flat 100m straight with an entry speed of around 6200-6500 RPM. I must be doing something wrong somewhere although I double checked everything twice. ???
Title: Re: Aero drag
Post by: Piers Prior on May 29, 2013, 10:10:34 PM
even though the aero is taken from real life i think it is still way too powerful for some reason, you may gain a tenth maybe sometimes around the whole lap in real life wheras you gain wayyyy too much in game :P
Title: Re: Aero drag
Post by: PiBoSo on May 29, 2013, 10:50:29 PM
Quote from: Hispinkness Prior on May 29, 2013, 10:10:34 PM
even though the aero is taken from real life i think it is still way too powerful for some reason, you may gain a tenth maybe sometimes around the whole lap in real life wheras you gain wayyyy too much in game :P

Tucking data is not taken from real life, so it probably needs to be tuned.
Title: Re: Aero drag
Post by: Piers Prior on May 29, 2013, 11:00:06 PM
Quote from: PiBoSo on May 29, 2013, 10:50:29 PM
Quote from: Hispinkness Prior on May 29, 2013, 10:10:34 PM
even though the aero is taken from real life i think it is still way too powerful for some reason, you may gain a tenth maybe sometimes around the whole lap in real life wheras you gain wayyyy too much in game :P

Tucking data is not taken from real life, so it probably needs to be tuned.
definitely haha it is overkill to say the least
Title: Re: Aero drag
Post by: Cory_Hayes on May 30, 2013, 01:51:26 AM
....ever done KZ1 at Daytona Oval? you will be going like 169km/h and then you duck and you get up to about 178km/h and in a slipstream the most I have gotten is 188km/h I think it was
Title: Re: Aero drag
Post by: KZ2_Iceman97 on May 30, 2013, 05:53:21 AM
Quote from: Cory_bro on May 30, 2013, 01:51:26 AM
....ever done KZ1 at Daytona Oval? you will be going like 169km/h and then you duck and you get up to about 178km/h and in a slipstream the most I have gotten is 188km/h I think it was
if you have lent your seat back far enough then it has the same effect as ducking especially in road racing with a shifter. A KT100 can get to around 16000 RPM at least with no drag and drafting down a long enough straight and hit maybe 100K/M if the gearing is right but having over 1 whole second difference from just ducking is ridiculous, even if the driver is very good at driving a KT100, they still would drop that much off, it's would be half a second maybe but definitely not a whole second
Title: Re: Aero drag
Post by: Nathan Dunnett on May 30, 2013, 06:50:43 AM
Hmm, I'll wait until beta 9 and have another try at this so I can mess around with the mini.
Title: Re: Aero drag
Post by: Piers Prior on May 30, 2013, 11:05:20 AM
the aero drag should have less difference the more powerful the kart, the cadets (mini 60) should have the most effect but by the time you get to kf1 etc it should make almost no difference 
Title: Re: Aero drag
Post by: KZ2_Iceman97 on May 30, 2013, 11:26:37 AM
Quote from: Hispinkness Prior on May 30, 2013, 11:05:20 AM
the aero drag should have less difference the more powerful the kart, the cadets (mini 60) should have the most effect but by the time you get to kf1 etc it should make almost no difference
no matter what class you race, ducking can give the slightest speed advantage even if you are in a KF1 or KZ. You have the power to pull yourself out and through the corner quicker but ducking still helps
Title: Re: Aero drag
Post by: Nathan Dunnett on May 30, 2013, 11:28:29 AM
It's very dependant on speed too, for example we should have much more drag at 120 km/h (KF1) than we do at 90 km/h (KT100J, cadets). A senior driver also has a bigger frontal area due a wider kart and taller driver. Does the new cadet kart use the same aero data as the senior karts?
Title: Re: Aero drag
Post by: oppolo on June 05, 2013, 02:20:49 PM
Quote from: Nathan Dunnett on May 29, 2013, 08:00:02 AM
and then if I tried to duck I would get like an extra 6-7 km/h whereas in real life it's more like 1-2 km/h tops if you're lucky and there is a head wind. Just by ducking I was gaining 1.5 seconds per lap at Lonato which is completely ridiculous for low speeds in good conditions. I haven't been on track with another kart that wasn't blinking and warping all over the place yet but I imagine the draft effect is massive, can anyone confirm this?
strange, in these days I'm testing different setups at essay, for now f100 and kf3, and with ducking the advantage is almost visually imperceptibly with trainer in front not ducking, I realize that ducking gives something only because the rev limiter of kf3 enter some 10 or 20 meters before