Top Speed/RX-8
 

This is addressed to those that have run on a legal track.
What is top speed you have experienced driving the RX-8. Please diffrentiate between normally aspirated and if your vehicle has a turbo.

Bone stock- 148mph. From 130 up it is VERY SLOW.

Havent done it since my performance mods.

bone stock 149mph...^agreed

149 downhill with a tailwind maybe. Or on a Dyno.

Wind resistance limits you to 130ish.

149mph also hit 150 going downhill a bit, did it with only my exhaust on.

Have not tried it since the turbo.

Without the limiter on a dyno our cars can go 160+ mph.

Its drag limited to about 145-150, the governor stops it at 148.

there is no limiter on the MTs ...ive honestly gotten it up to 149. the drag factor really holds you back

false, there is a limiter at 148.

Reason you saw 149 is because your speedo is off, which is common with digitial speedometers due to bald tires possibly, or new tires? Unless you have the RB reflash or AP your top speed ends at 148..

Thats why people claim there cars top out in 1st or 2nd gear at different speeds. Its not because all our cars have different gear rations :lol:

148mph

148mph

125mph. The computer kills the 2005 AT at that speed. And that's just third gear.

The 145 mph region top speed we are seeing is indeed the drag limited top speed to the MT car. Even if there is a limiter, I just don't see the car going much faster than this. At that speed it is barely crawling along against the drag.

In response to the statement about the speedo being off: So the limiter is limiting based on what if not the speedo? If there is more accurate data to be had to base the limiter on, why doesn't the speedo use that too?

the only limiter at that speed is mother nature. US MT cars are not electronically goverened. at all

147 on the speedo, airport run.

It would redline/beep in fifth, seemed to want to go faster, but sixth gear would just slowly lose velocity. A downshift back to fifth and it would get to 147 again.

Sixth is just too high, will have to check again with turbo.....

S

Can anyone prove this? Its pretty well documented through magazines that the RX8 is governed at 148 and drag limited to about 150.

Until I see some proof, Im going off facts. Governed at 148.

Thx for the figures. I have not taken mine to these speeds and was curious as to power vs drag and how much more boosted power is needed to exceed normal aspiration top end. If there is a limiter, I would assume this would not be a relevant question unless you could disable the limited speed.

Really? My 5th tops out at 135mph and I gotta hit 6th to make it painfully struggle up to 148mph :eyetwitch

148 MPH stock. 300 MPH or so with the JATO rocket assist mod.

-1.3L

Someone in Germany on the Autobahn with a US spec car, hit 155. There isn't a governor. Only on the AT is it governed.

149....on stock size tires...it took ages after hitting 135....

09's up have different gearing.

03-08's top out at 147 in 5th gear.

148 but it didnt took that long ...maybe a couple of miles :)

148 here..... SLOW AS HELL from about 132. That was bone stock. New Exhaust, Intake, I have only been to 133.

149 in 5th.

from the top of 4th it wasnt painfully slow, maybe .5mph per second.

Answer me this question,,
If the engine had a "Governor" like the AT models do. (And then not all.) Would you not feel the effects of the governor? I do when my car hits 125 on the track. It turns off. Just like turning the key off.
Now has anyone ever experienced that with a MT?

I couldnt tell, It was so slow but I stopped climbing at 148, kept it there for a couple seconds then let off.

I hit that on a slight downhill BTW, until that downhill I couldnt get over 147.

^no...

I believe that the top speed issue is from the drag coefficient and a lack of HP/TORQUE while stock.
There is not a governor on the MT. Other than design.

no what?

easys question

The only governor is..http://blogs.edweek.org/edweek/thisw...governator.jpg

Nope

I've hit the fuel cutoff a couple times, but no governor. Boy is that an unsettling sensation.

But that was due to over revving the engine, correct? I think everybody has done that at least once.

Ditto with fuel cutoff..

It's like, moving forward and accelerating then instantly stops gaining momentum, sounds kind of odd too..

i havent

That's because your special! :uhh:

if youve never hit fuel cut off b4..then you need to start having more fun when you drive....i hit it every now+then and i usually try to shift right b4 it hits

what rpm does the fuel cut off, i've hit it i just cant remember what rpm.

9000 or 9200 ish?

I have plenty fun and have never hit fuel cut-off either

i thought it was more like 9500 ish?

I hit 153 confirmed by GPS..... and the factory speedo was way off, the last 15-20mph seemed like it took forever though

I was in 5th as well. Didn't dare go to 6th... not nearly enough road.

your "facts" are wrong. the US 6port 6mts have never had an electronic limiter. the proof is easily found on a dyno , at the track or now simply by using something like the cobb. you'll find thru reading that this info has been known since 2003.

i personally have seen 155 on a dyno

151mph this weekend, GPS confirmed, it took a slight downhill slope but when road level'ed it kept up. My oil light went off right after though :p:

I was in 6th FYI. 5th doesn't get me past 137mph.

I'd argue that there isn't a governor for US MT 8s. I would have a hard time believing that a governor was added at a speed just past the stock drag-limited max speed. The main reason I don't believe there is a governor is from ... damn I can't find it. Still looking, but a youtube video.
On jack stands 6th gear, 180mph on the speedo. (5th hit the limiter at 153) If there was a governor anywhere before that, it would have kicked in, unless your going to argue that the computer knows that it really isn't going that fast? :)

Edit:
Here is is: http://www.youtube.com/watch?v=hE7p-D-PBeI

Edit:
Not saying 180mph is the top speed, since it doesn't look like he actually hit the rev limiter in 6th. Seems different from another one I saw that did a 0->186mph in 6th, not shifting on the way up, and it was a significantly faster rev, since he didn't have wheels/tires on. This one looks like it had some resistance to it, so probably still had the wheels/tires still on.

I've never hit the fuel cut-off, and I rev my car up all the time. I shift at 8500 or below; I see no reason to go over 8500, maybe there's a bit more power after that but I don't need it.

Fuel cutoff is like 9300-9400 rpms....

I have no comment on that video.

180mph.. on jackstands..