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Just out of curiosity does the cobb access port remove the top speed governor? I will be purchasing one of these soon and i was just wondering. i was doing some searching earlier and found out that stock the lgt comes with a speed governor at 139 what is the highest someone has reached in this car? im geussing it would top out without restrictions at about 160mph?
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Just out of curiosity does the cobb access port remove the top speed governor? I will be purchasing one of these soon and i was just wondering. i was doing some searching earlier and found out that stock the lgt comes with a speed governor at 139 what is the highest someone has reached in this car? im geussing it would top out without restrictions at about 160mph?

My understanding is that the speed governor is part of the stock map. The Cobb maps don't have a speed governor. When you remove the stock map and reflash it with a Cobb map, the speed governor is gone.

 

Regarding the theoretical top speed without the map, I calculated 157 mph at the 6,500 rpm redline in 5th gear with 215/45R17 tires. If you run taller tires or have a Spec B six speed, theoretical top speed would be higher. These calculations for for the 5MT. The AT has different ratios.

 

MPH = (rpm x tire diameter in inches)/(gear ratio x 336) = (6,500 x 24.62 in.)/([0.738 (5th gear) x 4.11 (ring and pinion)] x 336) = 157 mph

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Just out of curiosity does the cobb access port remove the top speed governor? I will be purchasing one of these soon and i was just wondering. i was doing some searching earlier and found out that stock the lgt comes with a speed governor at 139 what is the highest someone has reached in this car? im geussing it would top out without restrictions at about 160mph?

 

 

Took my 08 LGT to 141 and had about 800-1000 left on the RPM.......

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For sh!ts and giggles, I ran the theoretical top speed calcs on the much taller AT and Spec B 6MT top gears.

 

For the AT:

 

MPH = (rpm x tire diameter in inches)/(gear ratio x 336) = (6,500 x 24.62 in.)/([0.834 (5th gear) x 3.27 (ring and pinion)] x 336) = 175 mph (never going to pull that in 5th)

 

For the 6MT Spec B:

 

MPH = (rpm x tire diameter in inches)/(gear ratio x 336) = (6,500 x 25.62 in.)/([0.707 (6th gear) x 3.90 (ring and pinion)] x 336) = 180 mph (never going to pull that in 6th)

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For sh!ts and giggles, I ran the theoretical top speed calcs on the much taller AT and Spec B 6MT top gears.

 

For the AT:

 

MPH = (rpm x tire diameter in inches)/(gear ratio x 336) = (6,500 x 24.62 in.)/([0.834 (5th gear) x 3.27 (ring and pinion)] x 336) = 175 mph (never going to pull that in 5th)

 

For the 6MT Spec B:

 

MPH = (rpm x tire diameter in inches)/(gear ratio x 336) = (6,500 x 25.62 in.)/([0.707 (6th gear) x 3.90 (ring and pinion)] x 336) = 180 mph (never going to pull that in 6th)

What about 5-speed

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What about 5-speed

I posted the calcs for 5MT LGT earlier:

 

Regarding the theoretical top speed without the map, I calculated 157 mph at the 6,500 rpm redline in 5th gear with 215/45R17 tires. If you run taller tires or have a Spec B six speed, theoretical top speed would be higher. These calculations for for the 5MT. The AT has different ratios.

 

MPH = (rpm x tire diameter in inches)/(gear ratio x 336) = (6,500 x 24.62 in.)/([0.738 (5th gear) x 4.11 (ring and pinion)] x 336) = 157 mph

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auto is quicker than mt?

Not necessarily. That's just theoretical top speed based on redline in top gear. The AT has taller gearing, but probably can't pull that theoretical top speed. Top speed is a function of many factors, including whether there is enough power to overcome aerodynamic drag at a given engine speed. A 5MT LGT is more likely to hit its theoretical top speed because of its lower gearing.

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Here's the theoretical top speed calcs for a 2006 5MT Spec B:

 

MPH = (rpm x tire diameter in inches)/(gear ratio x 336) = (6,500 x 25.62 in.)/([0.738 (5th gear) x 4.11 (ring and pinion)] x 336) = 163 mph

 

The 5MT (2006) Spec B has numerically identical gearing to the 5MT LGT but rides on one inch larger diameter tires, so its effective/functional gearing is taller.

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Ok so what is the top speed in a 2.5i?

More than enough to get you arrested.

Not enough to let you get away with it.

:lol:

 

/I knwo people who've cracked 120, but pretty much everything can do that today

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the 2.5i has a problem with 120??

 

I took this going 115 in a impreza 1.8L

 

it was all flat level land and that was the highest I've seen but I mean the 2.5i should have no issue..

 

http://img181.imageshack.us/img181/1007/43fba483cd82sx2.jpg

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the 2.5i has a problem with 120??

 

I took this going 115 in a impreza 1.8L

 

it was all flat level land and that was the highest I've seen but I mean the 2.5i should have no issue..

Heck, I don't know. I was just told it'll do 120 by someone who owns one.

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I'm guessing a 2.5i could probably pull 120-130 max. I recall seeing an old road test of a previous generation normally aspirated 2.5l Legacy GT and the top speed was in the 120-130 range without a speed limiter.

 

I'd say it could do more than that. I was able to top my 99 LGT out at 137mph one time. So I would think a 2.5I should be able to get up to that.

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