what is your 8's top speed????
#226
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I hear it is drag-limited at 144. I hear it is governed at 148. I raced a charger and was going 146 and had it on a dyno going 148. Not sure what to tell you other than the 144 by car & driver or road and track, or motortrend was wrong in my case. I let off on the dyno cause I hit close to 9000 rpms so just stopped the run. I have not heard of anything proven over 148 yet but, doesnt mean it hasnt happened.
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Yeah, a turbo should get you to Redline in 6th. It takes just under 230 whp to push the air out of the way at that speed, plus overcoming rolling resistance. BTW, just adding another 30mph requires nearly double the HP. Needless to say, you'll be sucking down a LOT of fuel at those speeds.
#230
Yeah, a turbo should get you to Redline in 6th. It takes just under 230 whp to push the air out of the way at that speed, plus overcoming rolling resistance. BTW, just adding another 30mph requires nearly double the HP. Needless to say, you'll be sucking down a LOT of fuel at those speeds.
#234
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I believe the MT rx8's have 6 gears so ur top speed in 5th is not ur "top" speed..however everything stock I believe it cuts the injectors/shuts off at 156 or 158 not positive but I think I remember hearing that...correct me if i'm wrong and never ever bread the speed limit we know u did this speed on a closed course...
#235
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cd= .29
frontal area = 18ft^2
(.29 * 18 * 185.8981^3)/(15*10^4) = 223.5652
That whp. With a proper turbo kit you should be able to push 300 to the wheels, making 186 (redline in 6th) doable.
frontal area = 18ft^2
(.29 * 18 * 185.8981^3)/(15*10^4) = 223.5652
That whp. With a proper turbo kit you should be able to push 300 to the wheels, making 186 (redline in 6th) doable.
#236
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I believe the MT rx8's have 6 gears so ur top speed in 5th is not ur "top" speed..however everything stock I believe it cuts the injectors/shuts off at 156 or 158 not positive but I think I remember hearing that...correct me if i'm wrong and never ever bread the speed limit we know u did this speed on a closed course...
Reference: http://www.motortrend.com/cars/2007/...ons/index.html
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Coefficient of drag: 0.31
Last edited by alnielsen; 07-14-2008 at 11:50 AM.
#237
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According to Mazda Cd is .31 or .33 I think it was. They have updated on Mazdausa.com and the new one is .3 as the final drive is now the 4.777. That would mean that the new ones would not go as fast. According to the gearing, in 6th, you achieve 19.9 mph/ 1000 rpms. That would mean about 185 when the fuel cuts off at 9300 if you have your tires pumped well too. I am not sure but, the vette has as good Cd or better than the 8 and requires over 400 to the wheels to get to 190. If I am wrong, let me know but, I beilieve it is going to take more than 230 or even 300 to the wheels to top out at 185 on the open road. Unless you have taller tires, or have the computer program that allows more revs, a basic stock 8 tops out around 150 or so on the road and 185 on the dyno. It may hit 186 due to momentum for a short time but, like I said, there are other variables. 235/45 or even taller tires can achieve 186+ on the dyno. I have never gotten my 8 above 146 (ran out of road) and 150 on dyno. My experience anyway.
#238
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the lower Cd of the 2009 will help the .25 time and speed somewhat but looks as if you have to change gears little more often. Works for me
![Smilie](https://www.rx8club.com/images/smilies/smile.gif)
Last edited by cliffkemp; 07-14-2008 at 07:08 PM. Reason: spelling
#239
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http://www.precisionsite.com/auto-x/tools/ can tell you about the top speed.
#240
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On the German autobahn with my crappy camera going down a huge freaking hill 175.848 mph
![](http://i111.photobucket.com/albums/n131/fast92civic/283kmh.jpg)
Last edited by StuttgartRX8; 07-15-2008 at 05:00 AM.
#243
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Not my top speed and havn't topped out the 8' max speed personally cause I can't force myself to go past 120 but the other day on a mountain cuise with the local CO club I hit 96 in third going up hill.
#245
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the radio goes fast enough..im kinda wondering how fast im gonna be after the swap with the differant gearing in the tranny....i guess we will see, i wish i had the autobahn
#246
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i hit 145 in in 5th at 8000rpms on the parkway in jersey. the car def felt like it wanted to go faster but my radar started goin off. havent really tried it again since then