Great Info.

 

GUYS....aerodynamic is exponentially correlated to the design speed of the car. Have we ever wonder that Evo are designed not for highspeed travel compare to those European performance car? I've traded a 04 M3 for a 06 MR, I noticed that the MR once pass 130 mph, the car is like on steroid going to explode, take so much to get to 160mph, but under 100mph hands very very well compare to M3.

Even the 6th speed gearing on the MR seems like gear to redline at 165mph. I won't say Evo can't go faster than 165 mph, but the nature of Evo coming from Japan, they hardly have to drive more than 120 mph on their hwy.

Not just Evo owner, even STI owner agree that how often we go above 120 mph??? prolly 5% of the car life time, agree? Compare to those European performance which they prolly drive above 120mph daily. Consequently, Japan. RnD engineers will have tendency to produce a performance car have much greater Cd value.....and create more downforce under 120mph range.

 

I have a best of motoring video on the 06 STI. Subaru made the 06 STI very aerodynamic and supposed to be more stable at 150 mph than the M3. They even did a compare between the M3, STI, Mercedes benz (forgot what model), and another car (forgot also). The drivers said that the 06 STI is more stable at 150 mph than of all the cars they tested.

I have an 06 STI and I have had an 03 EVO. I can tell you that the STI feels alot more stable at 140 mph than what I remember of the EVO. Although, I never have had a chance to drive the MR at that speed, so I cannot tell you if there is a difference between the 03 EVO and an 06 MR. I am assuming there is a difference.

As far as underneath the 06 STI, you can tell some work had been done to the design of underneath the vehicle. It is pretty cool.

 

i think lots of those are rigged... just like top gear

 

Yeah, I can see that considering the driver was from Japan and so were the judges. Although it did look like it was more stable at that speed when they were going around the circuit. Also, I have raced an M3 up to 138 mph and I was pulling him. Whether or not that was because of me drafting him or going around a semi bend, do not know. All I can say is that he would not look at me. One of my nicer moments.

I love Top Gear. Is there anywhere you can buy dvd's on that show? My buddy downloaded some from the net, but it is okay quality. Any in Blue Ray yet

 

I might have to crawl under an STi one time

 

yeah, I want to replace the stock diffuser for an carbon fiber HKS Kanasai (sorry if spelled wrong) diffuser. It goes the whole length of the rear instead of just in the middle. Although I am not sure if an angled exhaust would work which is what I am looking at also. Anyways...

 

Agreed...^^

 

wow way to advanced for me

 

i can see y the sti are good at high speed u got to take out the plastic just to change the oil on that thing it cover up most of the bottom of the car

 

Try 10%,

 

very informative.. Great thread..

 

Great pics, I have had the idea for a while of trying to smooth out the airflow at the bottom of the evo with a flat panel going from side skirt to side skirt but to make i clear everything with would have to be pretty low and the addition of ll that material would add some weight altohugh since the weight is really low it would lower the center of gravity. Also thought about how much more aerodyenaic the evo would be withw lower roof line of a rear window that slopes more. Kinda like they did with this s2000 add on:

http://www.bulletproofautomotive.com...trearangle.jpg

 

Could you please tell me how you got the numbers for the Frontal Area? Is that calculated by multiplying the height and width of the car?

 

Wow, some of the stuff spouted in here is worse than the half-assed answers I've seen in my fluids engineering class.

That was pure gold. Even if the lift did account for the down force, the lift of the STI is not that much more than the Evo in relation to the downforce the STI produces. The numbers speak for themselves. The Evo's aero is not as good as the STI's aero. I'm curious to see the numbers at lower speeds such as 60mph a more realistic speed seen by production cars during rally races. Fluid equations are not linear, so I'm fairly sure that both cars see positive downforce at rallying speeds.

I'm guessing people are trying to justify why the Evo handles well compared to the STI in stock and in extremely modified forms. Here's a hint, while the front suspension geometry of the Evo is a little bit worse than the STI in terms of camber curves, the rear suspension is much much superior. It is the rear that really helps the Evos rotate. The multilink suspension rear allows for a much much better camber curve than the STI's strut suspension.

Great article! I think people should keep in mind that these cars are Euro-spec cars. This means the Evo IX does indeed have the rear diffuser bumper.