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Top Speed @ Circuit Vs Power

tk80

By tk80,
in Motorsport Discussion & Builds

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tk80 Proficient

tk80

Posted
Posted (edited)

Hi guys

Trying to understand power and top speeds at various race tracks. I know there are a heap of variables but i'm doing this just to get a general idea.

What would be useful is car, weight, power (kw at the wheels or estimate) and aero. Yes, other things like gearbox (sequential vs H pattern), gearing and traction come into it but, like I said, i'm just after estimates.

Ideally your speed will be via a gps system rather than a quick glimpse at the dash.

I'll start...

Car: 33 GTR
Weight: 1650kg fuelled with driver.
Power: 450awkw (claimed)
Aero: standard
Wakefield: 214kmh
Eastern Creek: 245
Mt Panorama: 272 but backed off very early cause i'm weak.
Add what ever tracks you've raced at.

I'm predicting that my speeds are low for the power level, but we'll see.

Edited by tk80
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mad082 Grand Master

mad082

Posted
Posted

The biggest factor in top speed is power, when comparing similar. Aero differences from different wings, whether you have the windows down, etc will play a small part as well. Grip levels will play a small part also as it determines how early you can get on the gas. Car weight and wheel weight also plays a part, as does tyre width. Skinnier tyres with a higher grip level will out perform wider tyres with lower grip, because wider tyres create more rolling resistance.

blackrex Mentor

blackrex

Posted
Posted

Your mid and exit corner speed out of the last corner onto the straight plays a major part in your terminal speed at the end of the straight, I have about 110kW atw in the Speads, but I'll hit 260+ at the end of the main straight at PI due to coming off of the last corner well.

hrd-hr30 Grand Master

hrd-hr30

Posted
Posted

R33 GTST,

350 rwhp,

Home made front splitter & Gt wing

Lakeside 57.6 sec

232 kph into carousel

217 kph into hungry.

F, 245/45/17 FZ201

R, 255/40/17 FZ201

QSTAR/Race chrono.

big speeds Noddy!

obviously got alot more power now than whenever we've been on the track together!

Noddy Proficient

Noddy

Posted
Posted (edited)

Only about 50hp, most gains have been in aero and suspension. These federals have such woweful grip i have put a lot of time into setup. LOTS OF TIME. As a result, mid corner speed os up 10-15 kph at carousel, hungry and estern loop. So looking forward to the new motor and better tyres.

I have a little ae86 levin out of Japan. Ex TRD cup car, its only got 150 rwhp, 920kg wet with driver, punching out 60.8 sec. Its na1600 on webbers 225/50/15 V70A. Such a fin car to drive. Changing gears @ 8500-9200 rpm...ind bending.

Edited by Noddy
hrd-hr30 Grand Master

hrd-hr30

Posted
Posted

got a video or link to the results Stuart?

Car: 180SX
Weight: 1360kg incl driver
Power: 200rwkw (claimed by previous owner when i bought it)
Aero: none
Box: stock H Pattern
diff : 4.3 shimmed viscous LSD

Tyres: Federal FZ201
Lakeside: 205.5km/h
Time: 59.6 (05/04/2012 on Natsoft and QR's 2012 midweek sprint results)

hrd-hr30 Grand Master

hrd-hr30

Posted
Posted

Only about 50hp, most gains have been in aero and suspension. These federals have such woweful grip i have put a lot of time into setup. LOTS OF TIME. As a result, mid corner speed os up 10-15 kph at carousel, hungry and estern loop. So looking forward to the new motor and better tyres.

I have a little ae86 levin out of Japan. Ex TRD cup car, its only got 150 rwhp, 920kg wet with driver, punching out 60.8 sec. Its na1600 on webbers 225/50/15 V70A. Such a fin car to drive. Changing gears @ 8500-9200 rpm...ind bending.

link to video or results for that too please :)

nfi Community Regular

nfi

Posted
Posted

S15 so not directly comparable.

Car: s15 200sx

Weight: 1150kg without driver

Power: 265rwkw

Aero: wing and front splitter

Wakefield: 199km/h (via data logger but that is with my foot still completely flat to the floor at the kink)

Eastern Creek: 228km/h

1.04.0 at Wakefield

1.39.6 at Eastern creek

Have a new engine in the car now that is yet to go to the track.

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