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Discussion Starter · #1 ·
how much horsepower does it take to push an R32 to 200mph (320kph)? anyone ever take their R32 up to that speed? How were the aerodynamics? I'm thinking a front diffuser to increase downforce on the front wheels may not be a bad idea...
 

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And a load and load of ££££££££££££££££££££££££

hahahahahahahah:wavey: :wavey: :wavey: :wavey:


****
 

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Discussion Starter · #6 ·
And a six speed gearbox
a six-speed won't do squat, as the final cog for every set I've seen is the same ratio as the fifth gear in a standard box - six gears just gives more shifting ratios between 1st and the top gear, and basically would make a car with a narrow powerband a bit more flexible.

Yeah, a front diffuser would increase downforce and drag, but stability at that speed is also pretty important. I'm interested in hearing first hand experiences of people who've taken R32s up into the 200mph zone.
 

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a six-speed won't do squat, as the final cog for every set I've seen is the same ratio as the fifth gear in a standard box - six gears just gives more shifting ratios between 1st and the top gear, and basically would make a car with a narrow powerband a bit more flexible.
Oh?

I thought six speed box like in the R34 had a longer top gear, my R32 is screaming its nuts off in fifth gear at 170 mph.

If its gotta rev another couple or three thousand RPM to reach the magic number then big dough would need to be spent methinx....
 

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Discussion Starter · #8 · (Edited)
Oh?

I thought six speed box like in the R34 had a longer top gear, my R32 is screaming its nuts off in fifth gear at 170 mph.

If its gotta rev another couple or three thousand RPM to reach the magic number then big dough would need to be spent methinx....
interesting, so the R32 has a gear-limited top speed of 170mph? What's your rpm at that point, is it around 8K?

You've got a point though, I'd never spend a dime on a six-speed unless that meant having a longer top gear - all the better for a higher top speed and also maybe better fuel economy on the highway.
 

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interesting, so the R32 has a gear-limited top speed of 170mph? What's your rpm at that point, is it around 8K?

You've got a point though, I'd never spend a dime on a six-speed unless that meant having a longer top gear - all the better for a higher top speed and also maybe better fuel economy on the highway.
The R34 6sp does 27mph/1000rpm in top with 18 inch wheels. The R32 does 23.9mph/1000rpm in top with 16 inch wheels. The R32 will do more than 170mph with the stock 5sp, trust me. The rev limit is 8200rpm, so it should theoretically make 196mph (+ some mph for tyre expansion) with 16 inch wheels.

Power = Force * Velocity = 0.5 * Air Density * Drag Coefficient * Cross-sectional Area * Velocity^3

Assume Cross-sectional Area ~ 2m^2
Drag Coefficient = 0.4
Velocity = 200mph = 88.89m/s
Assume Air Density ~ 1.225kg/m^3

Power = 0.5 * 1.225 * 0.4 * 2 * (88.89^3) = 344,156W = 344.156kW = [email protected] (not hubs)

Assume 25% loss between flywheel and wheels for 4WD, so add 1/3 (75 + 33% = 100), giving:

1.333 * 461 = 615bhp

If Cross-sectional Area is 1.8m^2 this falls to about 550bhp.
 

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Discussion Starter · #11 ·
well, that explains that :) thanks for the math, I can now see how running bigger diameter wheels can make a difference. But I don't I can add that extra inch (255/40R17 to 255/40R18)...because off the line acceleration will be equally geared up. Reachable with stock diameter wheels though, that sounds good.
 

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well, that explains that :) thanks for the math, I can now see how running bigger diameter wheels can make a difference. But I don't I can add that extra inch (255/40R17 to 255/40R18)...because off the line acceleration will be equally geared up. Reachable with stock diameter wheels though, that sounds good.
Stock wheels do mean stock/small brakes due to space constraints. I wouldn't like to have to stop from 200mph with stock brakes.:flame::runaway::flame:
 

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Just like everything there's more than just the math...I havent heard of alot of R32's hitting the magic 320...I'm gonna guess more like 700+ HP...of course your own abandoned airfield or sunday morning stretch of Autobahn to get there too...
 

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The R34 6sp does 27mph/1000rpm in top with 18 inch wheels. The R32 does 23.9mph/1000rpm in top with 16 inch wheels. The R32 will do more than 170mph with the stock 5sp, trust me. The rev limit is 8200rpm, so it should theoretically make 196mph (+ some mph for tyre expansion) with 16 inch wheels.

Power = Force * Velocity = 0.5 * Air Density * Drag Coefficient * Cross-sectional Area * Velocity^3

Assume Cross-sectional Area ~ 2m^2
Drag Coefficient = 0.4
Velocity = 200mph = 88.89m/s
Assume Air Density ~ 1.225kg/m^3

Power = 0.5 * 1.225 * 0.4 * 2 * (88.89^3) = 344,156W = 344.156kW = [email protected] (not hubs)

Assume 25% loss between flywheel and wheels for 4WD, so add 1/3 (75 + 33% = 100), giving:

1.333 * 461 = 615bhp

If Cross-sectional Area is 1.8m^2 this falls to about 550bhp.
Im lost back here :runaway:
 

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Hi
On topic, anyone know the speeds in 5th gear at say 6000, 7000, 8000 on standard R32GTR:)
Difficult to look at those speeds.. tunnel vision comes into the equation, redline is 170 on the clock in my car..thats 7500 rpm

All depending on the accuracy of the clock of course.

8250 rpm which it would have pulled to if there wasnt an artic lorry 500 yards ahead remains to be seen.. the A38 is a good place most of the time :)
 
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