Top speed on auto
 

Whats the top speed on the automatics? Does it top out at 125 in the auto mode, and if u switch it to the teptronic mode does it top out higher? Hows that work?

my friend got a 6speed up to 150 and he was only in 5th gear

Somebody got a 6sp to 184 on a dyno run. I dont know how, but I seen it! :D

:D

A few of us did that day...I was just lucky/thoughtful enough to get it on VIDEO! :D

I've got that video!

Yeah, cars would go a lot faster with no air resistance. Damn physics, always slowing us down!!

Everything I have heard limits the auto to 125 as you mentioned. I have not seen anything to suggest manual mode gets you any more.

govener?

Drag limited... Think about it... with 150RWHP if even that.... BTW if anyone got the balls to actually top out please indulge us and godspeed.

i got the balls but i have to wait till i break in my motor

topped out.. not yet but close
 

i got my manual up to 167... that was prior to the turbo,...which all my other mods will be on in four days... but at that speed driving on a highway, i hit a bump, and literally skipped a lane.... but i plan after the mods to take it to a track...

Now fella's...we all got balls here...lol

Yeah, 184 without wind resistance does not mean much. I wish we could test an 8 without the limiter holding it back at 148mph. I know I've heard of it reaching 150HP in 5th gear but apparently 6th gear has a limiter.

I was just wondering...wait a sec, how did it get that on the dyno if the limiter should have kicked in at 148???

I got my first 8 which was an auto up to 141mph shifting myself
125 is the speed limit for the cruise control
by the way no one asked what the 6 speed can do just the auto

I have a very hard time believing that a car with 192 horsepower at the crank is capable of 141 mph and a car with 238 is capable of 160 +. You guys must have been going down a mountain, it just doesn't add up.

Right - that proves the car is not 'electronically-limited' to 148. It proves the car has NO electronic speed limiter.

:)

- side note: Car and Driver claims this of the 6sp RX8:

Top speed (drag limited) 150 mph

167... must be downward right? ..

Hey Rage were you on a flat road? 141 is pretty fast.

the power required to get from 140-160mph is much much higher than the power required to get from 120-140mph. it's just not linear. (assuming the same drag coefficient). only had my auto to 120's in third, whatever that top's out at. I don't remember, it's been a while.

ONE OF THE FEW FLAT ROADS IN SOUTH DAKOTA

I'm going to say that the 167 was downhill. I did the stupid thing once and topped it out in fifth(150) and that was with a slight down hill....the car didn't have the power to go much faster if I had decided to switch to sixth.

I Did Not Top Out I Was Only At 6100 Rpms In 4th I Dont Think I Could Go Any Faster And Cops In Rapid City Love That Red Little Car So Much They Stoped Me Twice A Month Just To Say Hi Your Going 4 Over The Speed Limit So I Stoped Pushing My Luck

Wouldn't suprise me if the 6 speed does around 160, my eclipse with 30 less horsepower does 150. Heck my sentra does 140 stock with only 175ish hp.

238HP to the engine is not enough HP to hit 160mph guaranteed (on the RX8), I think I topped out at 154mph on my 94 RX7 with 255hp.

what's the coeff drag of the RX8 without the spoiler?

I would say the Auto8 can at best hit 140mph.

During high speed, the HP becomes exponential to keep up with the linear speed. Only two things matter for top speed on a flat windless road, the Coeff Drag and HP. Now the HP will have to be the actual RWHP which will have to account for the condition of the engine, ambient temp, moisture, air pressure, engine temp, fuel grade, and a lot more but I'm too dumb to think of it now. Hell it's 12:37am I'm going to sleep. This can even be done on paper and will actually be accurate.

Says who? you mean no head or tail wind?

...except 9000 rpms in 6th gear is really about 180mph.

(shrug)

sorry slight mis-calculation on the final drive ratio...looked funny to me too :D Would be 193 at 9000rpm in 6th.

And yes I meant assuming no head or tail wind on a flat road with coefficient of drag being .31 the 6sp would achieve 152 and the automatic 134. Obviously there are other things to consider but this would be fairly accurate based on the HP, gears, and coefficent of drag.

except it's 180mph at 9000...not 190...or 193. ;) In 6th gear, so says abbid, every 1k rpms is 20mph.

why 152 and not 153? or 148?

Guys, keep in mind that speedometers are notoriously inaccurate at these speeds, Car and Driver did a test a few years ago in which they compared car's speedometer indicated speed with a that of a radar gun. Most of the car's were 10 mph higher according to their speedo's at top speed than actual. A Porsche 911 showed 202 mph, while travelling at 181. The only exception was a Dodge Viper, which indicated 184 mph, but was travelling 186.

Will

Put the car on a stand, and take the dsc off. Then see how fast it goes. LMAO.

I highly doubt you got 140 mph in your auto 8. Its a load of bull all the 8s in bc went for a huge drive i got up to 186KM/h with a picture and that was downhill it just wouldnt go further so without proof i dont believe you!~

welp i've had my car for almost 2 months now ( 3700 miles... ). it's a 6mt. it'll get to 140 in a heartbeat. 140+ start to slow down but i've easily gotten her 160+ in about 1 mile. I didn't really feel like going too much faster as almost 170 in a 55 is not a good thing but highway 60 at 2am on a sunday is pretty dead.. not a car for 20 miles in either direction and it's a straightline for 10-20 segments and it's florida so it's flat and you can see 3-4 miles.

She went about 137 at redline in 4th and about 155 redline in 5th.

I have personally and easily I might add gone over 125MPH in my 8. Don't rmember the RPM range I was in but I know she had much more in her as I had to slow down. Again this was done at night with no one else on the road and a nice long open stretch of open highway. I am sure the 4-port 8's can easily reach 140MPH. Now can anyone prove it, that's the question... :D

This is in an AT?

There was a guy on here that swore his was limited to 125...he even said he had a video of it...

Yes I have the 4-port auto. Not sure if having a CZ unit tuned and installed in my 8 let me reach that speed and then some, but I know how fast I was going at the time and knew I had to slow down quickly for a sweeping left-hand turn. I got to 125MPH with no issues. I do have a CZ unit, Typhoon intake and Borla exhaust. Take it for what its worth, but I know "my" auto 8 can do 125+

The current impression is that neither car is limited at top speed as far as the computer goes. They're only limited in a horsepower vs drag and transmission situation.

Eventually you reach the maximum speed that the car can obtain vs the gearing on the transmission.

Ok I have an 2004 Auto RX8.

Top Speed is "LIMITED" by the "GOVERNOR" to "125 MPH".

Everytime I hit 125mph my car shuts off till it hits 120mph then it comes back on.

For the 2003's it might be different. But I dont really know since I have only been in mine.

My 8 is also a 2004 model. There were no 2003 RX-8's. Model year started in 2004 for the 8. Mine was bought in 2003 as a 2004 model. As I said I have a CZ unit, K&N intake, and Borla exhaust and I can def go over 125MPH in my auto. :D

Yeah same here a Stock AT RX8 can definately hit over 125mph I wouldnt doubt 135mph. But it just might take some long stretch of road.

I've touched 125 and mine didn't cut out.

my 5-speed runs 150mph.

^^^5-speed?

Yeah, the 4 port RX8 in Europe has an 5-speed manual gearbox instead of your automatic.

You learn something new everyday...had no idea that there was a 5-speed available.

Cool, thanks!

I have got a 192 hp 5 spd MT.
It was able to do 229 km/h(142 mph) on the Autobahn.
Maybe its faster now with more km's on the tacho..


https://www.rx8club.com/attachment.p...id=52808&stc=1

CaptinaZoom:


What gear where you in? I have a feeling it was 4th. :)

I'm pretty sure there a speed limiter on the US 4 port versions. I was traveling to vegas and constantly flooring the car and it did not hit over 125mph. I was stepping on the throttle for a good 1 min and it did not once hit 125. I have an HKS exhaust. I think the rpm around that range is 5500rpm? somewhere around that range.

That's fadt enough. Go to the track.

My car in 3rd gear topped out at 125mph on the dyno. Can't remember if I tried it in 4th but I would assume since I did a fully automatic run that it would have topped out in 4th as well and I can only remember reaching 125mph.

For the 5-spd MT the rev limiter stops you at 104 km/h i 2nd gear and 140 in third.
That's 65 and 87 mph..