5400rpm with S4 T2 Tranny, 5th Gear and 3.9 rear?

 

is 3.9 the rear that comes stock on the s4 tII? If so I'm thinking aroun 115, does that sound right?
I guess I could just go out and test it real quick for ya

 

stock t2 has 4.1
3.9 was from a na
i wasnt sure since i got km/h and it stops at 180:/

 

150-160ish?

 

128mph assuming stock-diameter tires. And no that's not a guess.

 

bad slpin, we all know driving on the street that fast is bad!! my s4 only gets to 125 on the highways..... =(

 

i worked it out and 180 km/h is only about 111 mph

at 5400 rpm's running in 5th (.762) and a final drive of 3.9 with 205 55 16's (circumference of 6.5136 feet) you hit ~134.5 mph

 

He didn't say that's what the speedo was reading, he said that's how high it reads. It's Japanese and 180km/h is as high as all their speedos go.

Your circumference is too big. You can't get an accurate figure from the tires specs, plus that doesn't take into account the deflection due to the car's weight. You have to measure the radius of the tire from the ground up to the centre and use that number. For a stock tire thats 300mm (11.8").

 

yes they are stock tires, 91 with 205 something 15...
thank you for the numbers

i was kinda curious cause it was still accelerating pretty good and i wasnt flooring it...

 

well i don't wanna bash heads here but i know it wasn't really reading 180 km/h... that's just what it maxxed out at right? i found it odd that that's all it read to as i have lived on the east coast of the US all my life

and as far as the circumference i figured the wheels would squish less at higher speed because of centrifugal force pulling the tire away from the rim so the figure may actually be between both of ours but i could be wrong

 

No bashing, just clarifying. The speedo does keep going higher but that's where the numbers stop. It looks pretty cool with the needle pointing straight down...

Not with street tires. You see big drag slicks do that but that's because they have very soft sidewalls. Tire growth from centrifugal force is minimal for street tires. I know in my car the calculation works out perfectly at a range of speeds so the diameter must remain fairly constant.

 

actually, NZ... it doesnt keep going... it stops at 180 and stays there
i think it is only the s4 gauges that keeps going....