Just for fun, I pushed the mph limits of the car

[dscoobydoo]

OK, to work the gear ratios, the final drive would have to be changed as well as the extra gear added and the ratios modified.

Obviously this is only a what if, because it is too costly to try all of this.

Power will overcome aerodynamics only to a certain point.

Gearing, power and aerodynamics all play a major role.

[skid542]

I wanted to add a couple things to this discussion.

A - An 05 STi will reach over 150 mph, I've sat in the passenger seat watching the tach and speedo and it was still pulling when we ran out of straight. The tach was about 6.1k in 6th and climbing.

B - The wing on the STi is a highly engineered (or so I'm pressuming ). It will have a particular speed that corresponds to minimum induced drag. The 'top' part produces parasitic drag but it is really the 'bottom' that produces the drag. The drag is a result of the lift that the wing is producing.

C - I am really curious to know where you got your drag coefficients. I know they publish them for some cars but I'm just curious to know where you got the ones for the legacy. If the drag of the legacy is to be considered at high speeds there is a little bit more to it than D = 1/2*Cd*ro*S*V^2. That will be the drag the wing produces but the car itself will start developing seperation bubbles that may or may not stay attached at high speeds. These bubbles will also form around irregularities in the body work, aka dents, and further compound an accurate drag analysis. The boundary layer effects will be largly less noticable at low speeds than high speeds so unless the drag coefficients that are being quoted are for high speeds then they are a little irrelevant, not wholely but far from concrete.

So will the Legacy reach 163? I personally doubt that it will without a change in gearing but with enough power I believe it'd be possible. They would be plenty of turbulance produced at that speed but as it's said in the aviation world - put enough power on a brick and it will fly. 140 though I see as being plenty realistic, 150 I could even see but I would be inclined that's about when the drag and power curves start meeting. Just my three cents on the matter.

[azn2nr]

it is my opinion that the lecgacy will reach a grand total of 140. today at 130 i had 1500 rpms left and the car was pulling lightly at 12 psi. at 15 it would get there much fastar

[kastrix]

I'm not claiming my spedometer is 100% accurate but i've hit 138 down a huge straight hill and thats as fast as i could get it.

[dzx]

I've buried the speedometer at 140 quite a few times.

[sandals]

on my way to Toronto last year, i had my legacy pegged at 140 on the QEW... it was just me and this eagle talon at like 3am.. he cut out at about 120 or so, so i kept it down.

since then, the car is dead.. looking for a new one. rar.

[nzKAOSnz]

You bastards. The JDM Legs are limited to 180kmh (110mph). I can hit that in 4th&5th in my N/A with a 3.90 diff. (4th - its a race between the revlimiter and the speed limiter - however im not really into doing that coz not too keen on high revs for long time).

[douglas vincent]

I always hate to bring this up, but if you are driving on the 14" tires, the speedo MAY be off by 10%. Both my 1990 wagon and 1990 sedan were/are off this much. Once I put on stock WRX rims and tires on my wagon, I am with a few % points of perfection.

I bring this up cause I once hit 130. But then once you figure in the 10% difference, then I was only doing 117. BIG difference. And if you think you are doing 140, and are 10% off, then 140 = 126, not even close.

Not doubting anyone, just posting my experience.

And when I did do 120 on my 16" rims (Hey I was safe, it was midnight in a handicapped school zone), it felt WAY FASTER than when I did it on my 14" rims.

[BAC5.2]

My car rather quicly clears and exceeds 130mph and strongly pulled towards 140mph. I shut down just as the speedo tapped 140mph.

... not that I do this kind of thing with any regularity. If I want to go fast, I get on the motorcycle. It gets to 140 a LOT faster than the legacy.