I was just surfing Wikipedia, and it claims the JDM RX8 redlines at 9500 rpm vs the US version at 9000 rpm.

 

that makes me wonder what would the 3 rotor puerto rican rx-8 redline would be.

 

oh thats interesting

 

sigh

 

Since when does Wikipedia know anything????

They are probably confused between "redline" (the mark on the gauge) and "max revs" (ignition cutoff). Both are the same, JDM or export.


S

 

^ that's what I always thought...

 

Yup, the redline for JDM is 9000 rpm, with cutoff at 9500rpm - I have the JDM Type S model.

 

THe thing you have to remember about Wikipedia is that anybody can post stuff on there. It doesn't mean it's correct.

 

9500 rpms on the tach is really 9000 rpms

 

yeah, my tach goes to 9500 (indicated) on my base 6 spd US model

 

I think that the Tach is off in the upper ranges 8500+rpm it seems to be off by about 250-300rpm.... Also I believe that actual cutoff is around 9300rpm.

 

Amount of rotors is not what dictates redline... Besides I'm pretty sure, though I have not read that thread, that they are merely using a 20B in the rx8. I really doubt they would've built a 3 rotor Renesis. Therefore the redline the same as the 20B cosmo, unless they did some internal modifcations, new intake, standalone, etc etc etc.

 

avtuall more rotors means more rotating mass and more stress on the e shaft and flexing SO more rotors does equal less redline. also i dont see where he said 3rotor renesis

 

I was assuming that's what he meant considering all he said was 3 rotor rx8 and thought the redline would be higher. I couldn't understand why he thought redline would be higher than 2 rotor renesis, considering it's not even the same thing.

Either way, if my assumption was wrong, his thought process was wrong also.

More goes into redline than rotating mass alone... More rotational mass but properly balanced can rev higher more safely than less rotational mass on stock balance.

 

the tac is off, but the fuel cutoff is exactly 9000 rpms (well at least thats what the ecu says it is)

 

What do we need to do to get that extra 500rpm on the tac? I plan on putting the taller 4.778 r&p in that will cause a 500rpm offset compared to the stock 4.444.

Will this work?

 

I don't think I understand your question... changing your rear gear will not effect your tach

 

If the JDM fuel cut off is 9500rpm, then I don't see a problem with changing the 9000rpm cut-off. Maybe a change for emissions? This would definitely generate higher peak power.

This would generate greater acceleration with a higher peak rpm, especially with the 4.778. It doesn't seem impossible, just need to fool the pcm. That is all.

 

In what way? Most rx8 dynos I see power is dropping off before the 9000 rpm mark, and I was under the impression the rx8 makes peak power at like 8000-8500. So higher redline wouldn't change peak power unless more things are changed.

 

peak hp is at 8500

 

Does the hp on a CZ tuned engine still peak out at 8500rpm?

 

In my opinion, the issue is not tune or other simple mods for why it doesn't peak at redline. Either the ports just can't flow enough to keep making power up there, or the intake manifolds become a restriction and cannot flow enough.

Either way it's not a simple fix.

I don't really see why it matters much. Who cares if your power "peaks" 500 rpms later? It's not like the rx8 power dies completely past 8500, it just starts to fall. It still makes useable power past there, if it didn't Mazda would not have had the redline at 9000.

 

It's Wikipedia... if you don't like it change it! :D

 

I'd be willing to bet the farm that the JDM fuel cutoff is 9500 rpms on the tach which is 9000 actual rpms - just like our's

 

jus like everyone said. 9k redline. yet 9500 cutoff. thats all its all the same. but 8500 is our peak