RX-8 Trouble
#26
Rotary , eh?
iTrader: (1)
My experience has shown the RX transmission to be more 'old sports car' like; it doesn't really like 1st gear unless you are at a standstill (oh ya, it will DO it, but doesn't like it) and 2nd is so low anyway that the revs build quickly into the power band. You can indeed double-clutch while downshifting with OK results but I find that if I just rev-match while downshifting (works great with heel-and-toe) the trans just falls into the next gear slick as anything.
double clutch + heel-n-toe.
now that was an interesting learning experience.
#28
I'll snap his neck.
Exactly. The redline is the maximum safe rpm for an "end user" to run it to. And the redline on this car is set because of the transmission, not the engine. From what I've read and been told by a senior mazda tech, the engine can take much higher rpms. He said they have a rotary at the training center that they go to that has been run at 12000 sustained rpms regularly on a test stand. He said he thinks it is the same engine that they used when he first went to training back in the late 80s.
#29
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i prefur to not run 1st up too much because of the aforementioned problem. as long as i'm in the country or a highway, i always think 2nd is a hoot run up! The 2-3 shift just feels SOO much smoother then then 1-2 shift to me. Feels more reassuring.
#30
Yea, I usually do my redlining in second gear or on the highway in third. First gear feels a little weird because if you let go a little on the gas, the synchros kick in, very unpleasant.
#34
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My 2 rotors worth:
Hitting 9k doesn't magically dispell all carbon from your engine. Think of your engine as an oven (which most of do, anyways) - When you turn the dial up to the "Clean" setting, the oven doesn't become clean instantly. It needs sustained and prolonged heat to get that gunk out of there. Technically, the "clean" setting on our Renisis ovens is somewhere around 7000.
Much like an oven in your kitchen, when you're producing this much heat you don't want it to spread to everything around it - they are not quite as resilient to heat as the oven. That's why the oven in your house has a crapton of insulation around it. Our engines, however, do not have said insulation.
Instead, they have radiators, oil coolers, and an assortment of vents. These "insulation" measures, however, require wind to work... lots and lots of high-speed wind.
Since the gearing in 1st gear is so short, redlining ONLY in 1st gear doesn't accomplish much. You aren't in the "cleaning" zone long enough to really generate the required heat, nor should you hold your revs up that zone in 1st gear since you won't be traveling fast enough to push enough air under your hood (for prolonged periods, that is).
2nd & 3rd gear are more ideal since they'll hold in you the 7k-9k area longer, as well as blow more air under the hood. But, truth be told, as long as you drive your 8 like it's a sports car, and not like you're trying to save money on gas, you'll be fine. Let her rev high and stay high and she should never get "dirty" in the first place!
Hitting 9k doesn't magically dispell all carbon from your engine. Think of your engine as an oven (which most of do, anyways) - When you turn the dial up to the "Clean" setting, the oven doesn't become clean instantly. It needs sustained and prolonged heat to get that gunk out of there. Technically, the "clean" setting on our Renisis ovens is somewhere around 7000.
Much like an oven in your kitchen, when you're producing this much heat you don't want it to spread to everything around it - they are not quite as resilient to heat as the oven. That's why the oven in your house has a crapton of insulation around it. Our engines, however, do not have said insulation.
Instead, they have radiators, oil coolers, and an assortment of vents. These "insulation" measures, however, require wind to work... lots and lots of high-speed wind.
Since the gearing in 1st gear is so short, redlining ONLY in 1st gear doesn't accomplish much. You aren't in the "cleaning" zone long enough to really generate the required heat, nor should you hold your revs up that zone in 1st gear since you won't be traveling fast enough to push enough air under your hood (for prolonged periods, that is).
2nd & 3rd gear are more ideal since they'll hold in you the 7k-9k area longer, as well as blow more air under the hood. But, truth be told, as long as you drive your 8 like it's a sports car, and not like you're trying to save money on gas, you'll be fine. Let her rev high and stay high and she should never get "dirty" in the first place!
#35
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EDIT
Yes, I realize that's not the synchros, but just because he didn't know exactly what causes it doesn't mean you need to get mad at him.
Last edited by ½mv²; 07-29-2007 at 03:51 PM.
#36
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Exactly. The redline is the maximum safe rpm for an "end user" to run it to. And the redline on this car is set because of the transmission, not the engine. From what I've read and been told by a senior mazda tech, the engine can take much higher rpms. He said they have a rotary at the training center that they go to that has been run at 12000 sustained rpms regularly on a test stand. He said he thinks it is the same engine that they used when he first went to training back in the late 80s.
the engine can rev higher, and the other parts around it combine to be the limiting factors.
but incorrect in the time frame: The engine the tech is talking about, if it is from the 80s is not our engine. the renesis is a new version made for the 8, therefore hasn't been around long enough to be the "same engine . . . [from] the late 80s."
#37
Registered User
I think he was refering to that unplesant *clunk* you hear in the tranny as the car jerks if you take your foot off the gas too soon before engaging the clutch.
EDIT
Yes, I realize that's not the synchros, but just because he didn't know exactly what causes it doesn't mean you need to get mad at him.
EDIT
Yes, I realize that's not the synchros, but just because he didn't know exactly what causes it doesn't mean you need to get mad at him.
#38
Rotary , eh?
iTrader: (1)
I think he was refering to that unplesant *clunk* you hear in the tranny as the car jerks if you take your foot off the gas too soon before engaging the clutch.
EDIT
Yes, I realize that's not the synchros, but just because he didn't know exactly what causes it doesn't mean you need to get mad at him.
EDIT
Yes, I realize that's not the synchros, but just because he didn't know exactly what causes it doesn't mean you need to get mad at him.
#39
Registered User
#40
Rotary , eh?
iTrader: (1)
because its geared so low. it happens in any car in 1st gear if you accelerate hard and then just let off the gas. Its just momentum being shifted. And the powerplant frame making everything stiffer takes any damping effect out of the driveline. That is a good thing...not to be putting that stress on the driveline. A lot of cars don't have a powerplant frame so its less noticeable in those cars because the driveline soaks up a good portion of the energy.
#41
it really shouldent matter what gear you redline it in....the rx8 loves to revvv..i think the problem here is he downshifted without rev matching and put a sudden strain on the engine...like hitting a wall without there actually being one. =/
#44
I think he was refering to that unplesant *clunk* you hear in the tranny as the car jerks if you take your foot off the gas too soon before engaging the clutch.
EDIT
Yes, I realize that's not the synchros, but just because he didn't know exactly what causes it doesn't mean you need to get mad at him.
EDIT
Yes, I realize that's not the synchros, but just because he didn't know exactly what causes it doesn't mean you need to get mad at him.
![Banghead](https://www.rx8club.com/images/smilies/banghead.gif)
#45
Rotary , eh?
iTrader: (1)
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