WTF!!! RX8 vs 7Gen....
02-27-2005
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WTF!!! RX8 vs 7Gen....
ok so i was on my way to work and cruising 40MPH @ 45MPH Zone and here comes another pinoy boi on his brand new RX8 NA haulin *** about 60-70... so I catched up on him... i was in the middle lane and he's on the outer lane... i switched lane and followed him...
the next stop light is red... i'm behind him... so the light turn green... we both started slow and started picking up, he changed to the middle lane and @ 40MPH we are both even then, we went at it, I readlined on 2nd to 3rd and seeing him falling back easy... WTF!!!???
i thought they have 240 NA on this 35K$ rotary???
RX8 NA vs. 7Gen@8PSI
I PWNED RX8??? I haven't raced an NA or Boosted RX8's before, i've seen boosted RX8 on video and they haul ***...
or he didn't go at it, when I thought he did... and thought i pwned him... then i deserve >>>
haha 
the next stop light is red... i'm behind him... so the light turn green... we both started slow and started picking up, he changed to the middle lane and @ 40MPH we are both even then, we went at it, I readlined on 2nd to 3rd and seeing him falling back easy... WTF!!!???
i thought they have 240 NA on this 35K$ rotary???RX8 NA vs. 7Gen@8PSI
I PWNED RX8??? I haven't raced an NA or Boosted RX8's before, i've seen boosted RX8 on video and they haul ***...
or he didn't go at it, when I thought he did... and thought i pwned him... then i deserve >>> haha Last edited by pnoyster2k1cvic; 02-28-2005 at 09:43 PM.
02-27-2005
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Originally Posted by hotrodcivic2004
well u r boosted.......
and can somebody tell me the weight of the RX8 for the last 30mins, I can't find the damn information... they're not too proud for some reason...
Last edited by pnoyster2k1cvic; 02-27-2005 at 03:17 PM.
02-27-2005
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Hey man, remember me?
Too bad I couldn't see that, it would have been fun... but maybe he was just a shitty driver. Either way, score 1 point for you...
A book I have says the RX-8 has a curbweight of 3029 lbs (1375 kgs)... hmm...
Too bad I couldn't see that, it would have been fun... but maybe he was just a shitty driver. Either way, score 1 point for you...
A book I have says the RX-8 has a curbweight of 3029 lbs (1375 kgs)... hmm...
02-27-2005
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Originally Posted by pnoyster2k1cvic
yes, but boosted 7th gens are only about 160-170 @ 8PSI... i guess i just thought RX8's are some fastest ****'s out there... hmmm
and can somebody tell me the weight of the RX8 for the last 30mins, I can't find the damn information... they're not too proud for some reason...
and can somebody tell me the weight of the RX8 for the last 30mins, I can't find the damn information... they're not too proud for some reason...
You got 160-170 WHP in a 7th gen civic. Your dangerous, since your car only weighs 2500 pounds if its one of the early model ex coupes.
02-27-2005
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Rep Power: 270 Was it the Sports Edition, Shinka or base? Base is less then 200 hp. Either way, its 3000lbs vs 2500-2700 lbs with similar hp
02-27-2005
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Rep Power: 0 ok not to be a **** but this really has nothing to do with autox or roadracing. please post threads like this in the track/street/strip forum. either way good job, i guess.
take that sh*t to the track.
take that sh*t to the track.
02-27-2005
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Originally Posted by QBoi
Was it the Sports Edition, Shinka or base? Base is less then 200 hp. Either way, its 3000lbs vs 2500-2700 lbs with similar hp
he might be an AT also...so
.01sec 1/4 mile = 10WHP
100lbs = .01 sec 1/4 mile
1000lbs = 1.0 sec 1/4 mile
ooh 1sec advantage yesss!
02-27-2005
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Originally Posted by CrazyCakes
ok not to be a **** but this really has nothing to do with autox or roadracing. please post threads like this in the track/street/strip forum. either way good job, i guess.
take that sh*t to the track.
take that sh*t to the track.
sorry guy sheeessh! relax... do you go around to all peoples post and tell them it's on a wrong furom? and besides street racing = roadracing what's the big difference... :P
when I race i don't do weaving traffic back and forth, or run redlights and or race on heavy traffic...... thats when they get into an accident...
Last edited by pnoyster2k1cvic; 02-27-2005 at 06:05 PM.
02-27-2005
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Rep Power: 0 there is a difference man.....one forum is for track/street/strip....one is for autox or roadracing...which is a completely different type of racing than what you just did on the street with that rx8.
02-27-2005
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Rep Power: 278 rx-8's aren't all that impressive at all
I thought it was in the same level as s2k/350z but it was a little behind (dont' get mad Nookiemaster
)
u're set at 8psi? what do you run in 1/4 mile? low 14's to mid 14's right?
then you should be able to take Rx-8 with GOOD DRIVING SKILL
good kill man
I thought it was in the same level as s2k/350z but it was a little behind (dont' get mad Nookiemaster
)u're set at 8psi? what do you run in 1/4 mile? low 14's to mid 14's right?
then you should be able to take Rx-8 with GOOD DRIVING SKILL
good kill man
02-27-2005
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Originally Posted by 4bangin
there is a difference man.....one forum is for track/street/strip....one is for autox or roadracing...which is a completely different type of racing than what you just did on the street with that rx8.
Originally Posted by chrisleecool
rx-8's aren't all that impressive at all
I thought it was in the same level as s2k/350z but it was a little behind (dont' get mad Nookiemaster)
u're set at 8psi? what do you run in 1/4 mile? low 14's to mid 14's right?
then you should be able to take Rx-8 with GOOD DRIVING SKILL
good kill man
I thought it was in the same level as s2k/350z but it was a little behind (dont' get mad Nookiemaster
)u're set at 8psi? what do you run in 1/4 mile? low 14's to mid 14's right?
then you should be able to take Rx-8 with GOOD DRIVING SKILL
good kill man
Last edited by pnoyster2k1cvic; 02-27-2005 at 06:33 PM.
02-27-2005
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Originally Posted by pnoyster2k1cvic
aight damn! point taken already
^^^who's nookiemaster?
^^^who's nookiemaster?
he is an rx-8 owner with the 6-spd sports package.
02-27-2005
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Originally Posted by QBoi
he is an rx-8 owner with the 6-spd sports package.
... 
02-27-2005
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my civic has no boost
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Originally Posted by pnoyster2k1cvic
nice... but god damn RX8 is a speed oasis... a 1.3liter imagine if it is modded and bored to 2.0liter or more and turbo charged @ 15-20PSI or SS... my god... imagine the whp power it could make... i'm soooo excited ...
... 
02-27-2005
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Rep Power: 0 ^^^^hmmm, I kind of like them. I would say that they are a mid 14 sec car and if you hung with one you had to be hitting the bottle because there is no way. I personally think that a boosted one would be one of the nicest cars around. Think about it the sound of the rotary engine a 9K with a BOV that would be nice
02-28-2005
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Originally Posted by Boilermaker1
No Street **** In The AutoX Forum
Originally Posted by hotrodcivic2004
how do u bore a rotary. hmmm. i guess u could.
hahahaha sorry i'm a nooby i deserve this>>>
02-28-2005
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Rep Power: 0 RX8's are mid 14 second cars, and they handle like they're on rails.
Also, some other points-
1- You cannot "bore" a rotary.
2- If you want huge power, swap in a 3-rotor turbo from the last generation of RX7's.
3- If you're a very good mechanic, try to mate 2 RENESIS rotaries at the crankshaft, as some guy did with the 13B some time ago. You'd make insane power N/A, on the order of 400 whp.
Remember, 1 rotor has the rough equivalent of 3 typical cylinders.
www.howstuffworks.com
Also, some other points-
1- You cannot "bore" a rotary.
2- If you want huge power, swap in a 3-rotor turbo from the last generation of RX7's.
3- If you're a very good mechanic, try to mate 2 RENESIS rotaries at the crankshaft, as some guy did with the 13B some time ago. You'd make insane power N/A, on the order of 400 whp.
Remember, 1 rotor has the rough equivalent of 3 typical cylinders.
www.howstuffworks.com
02-28-2005
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Originally Posted by senseiturtle
RX8's are mid 14 second cars, and they handle like they're on rails.
Also, some other points-
1- You cannot "bore" a rotary.
2- If you want huge power, swap in a 3-rotor turbo from the last generation of RX7's.
3- If you're a very good mechanic, try to mate 2 RENESIS rotaries at the crankshaft, as some guy did with the 13B some time ago. You'd make insane power N/A, on the order of 400 whp.
Remember, 1 rotor has the rough equivalent of 3 typical cylinders.
www.howstuffworks.com
Also, some other points-
1- You cannot "bore" a rotary.
2- If you want huge power, swap in a 3-rotor turbo from the last generation of RX7's.
3- If you're a very good mechanic, try to mate 2 RENESIS rotaries at the crankshaft, as some guy did with the 13B some time ago. You'd make insane power N/A, on the order of 400 whp.
Remember, 1 rotor has the rough equivalent of 3 typical cylinders.
www.howstuffworks.com
it's been pointed up top...but what can be done to an NA RX8 to make some serious gains? just stock internals, maybe an additional FMU... coz i just did over rated the RX8 to be really quick NA... does it even have space for boost or SC???
02-28-2005
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Originally Posted by pnoyster2k1cvic
^^^hehehe sorry it's been pointed up top...
but what can be done to an NA RX8 to make some serious gains? just stock internals, maybe an additional FMU... coz i just did over rated the RX8 to be really quick NA... does it even have space for boost or SC???
it's been pointed up top...but what can be done to an NA RX8 to make some serious gains? just stock internals, maybe an additional FMU... coz i just did over rated the RX8 to be really quick NA... does it even have space for boost or SC???
They just released a turbocharger for the rx-8. There is a video somewhere around here of the rx-8 tced in action. There is plenty of space in the rx-8 engine bay.
02-28-2005
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Rep Power: 0 Turbos and nitrous work incredibly well with a rotary, since they have a much greater "intake stroke" as compared to a piston engine (270 degress vs. 180), as well as benefit from an effect known as "inertial supercharging," which crams even more air into the combustion chamber even after the volume starts to decrease.
So, a rotary should benefit more from airflow increases in the intake tract (Port/polish, intakes, maybe larger valves, etc.) as well as way more power under boost, pound for pound, than any typical piston engine... except for possibly very large displacement.
If you need some more detailed info on the matter, read up here. http://www.yawpower.com/dectech.html ... but you need to know how a rotary works or this won't make any sense at all.
Yes, there's plenty of room in an RX8's bay for all kinds of toys. Just dump all the plastic coverings and you're good to go.
So, a rotary should benefit more from airflow increases in the intake tract (Port/polish, intakes, maybe larger valves, etc.) as well as way more power under boost, pound for pound, than any typical piston engine... except for possibly very large displacement.
If you need some more detailed info on the matter, read up here. http://www.yawpower.com/dectech.html ... but you need to know how a rotary works or this won't make any sense at all.
Yes, there's plenty of room in an RX8's bay for all kinds of toys. Just dump all the plastic coverings and you're good to go.
03-01-2005
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Don't worry I'm not mad...it's true the RX-8 seems to get killed on the street pretty often, but I can almost guarantee you that you raced an automatic 197 hp model. On my last run at midnight mayhem in vegas, I got a 14.8. Similar powerband to an S2K, but a bit heavier, so a few tenths of a second behind.
The car is extremely hard to launch, so it's hard to come across good drivers. It took me ALOT of practice just to get under 15 seconds.
The story with the horsepower fiasco was basically that Mazda originally released the RX-8 with 248 hp, but the EPA in the name of tree huggers everywhere, released a mandate that all 2004 model year cars come equipped with cats that would last at least 200K miles. So, in order to cool down EGT, Mazda reflashed all ECU's and in turn the car runs pig rich, so the power was downgraded to 238. However, due to the sloppy tune, no two RX-8's are equal. They vary. Some have had some pretty bad luck, in that they only dyno 170ish to the wheels. Others got lucky and still dyno around 210. Personally, I have not dynoed my car.
However, there is a solution. Canzoomer, a well respected rotary tuner, has released a product that tunes afr and timing in the name of restoring what should have been. In some instances, people have seen even better than what was originally intended for the renesis through simple tuning. Think of it as Hondata.
I was getting ready to purchase this, and lay a baseline dyno, however, Greddy's turbo makes 242 whp on 5 psi. This is on a very small turbo (see www.greddy.com) and on very low boost. Just when I was getting excited about this, ssr engineering released their turbo, and with a more appropriate tune, made 292 whp on similar boost levels. HKS and blitz are also releasing superchargers, and Mazdaspeed has a rumored supercharger in the works. Street porting the renesis although a very simple concept should be left to the pros, but guys (guitarjunkie dave) have been seeing some excellent results.
The car is still an amazing car. 1.3L NA with 238 hp. That's 183 hp/Litre. The old FD made 255 with twin turbos. However, the RX series has never been about pure power, but more about handling dynamics, chassis rigidity, suspension tuning, and adequate power. Remember, compared to the Supra and 300ZX, the FD was also underpowered, but still faster around a track. The RX-8 ties the BMW M3 around top gear's lotus designed track. Thank the 50/50 weight distribution for that, and the amazingly stiff chassis (50% more rigid than the FD with 4 doors and no b-pillar).
So, the car is a victim of the EPA really. I wish they would pick on people like SUV drivers instead.
In short, I think that pnoyster raced an auto 8. I have encountered boosted 7th gens in so. cal and I didn't have a problem putting him behind my rear bumper. Either that or he raced a guy who (like most 8 owners) is still learning about his car's powerband. If you catch an 8 in the wrong gear, it's easy to put him down because of the low torque numbers.
Don't worry I'm not mad...it's true the RX-8 seems to get killed on the street pretty often, but I can almost guarantee you that you raced an automatic 197 hp model. On my last run at midnight mayhem in vegas, I got a 14.8. Similar powerband to an S2K, but a bit heavier, so a few tenths of a second behind.
The car is extremely hard to launch, so it's hard to come across good drivers. It took me ALOT of practice just to get under 15 seconds.
The story with the horsepower fiasco was basically that Mazda originally released the RX-8 with 248 hp, but the EPA in the name of tree huggers everywhere, released a mandate that all 2004 model year cars come equipped with cats that would last at least 200K miles. So, in order to cool down EGT, Mazda reflashed all ECU's and in turn the car runs pig rich, so the power was downgraded to 238. However, due to the sloppy tune, no two RX-8's are equal. They vary. Some have had some pretty bad luck, in that they only dyno 170ish to the wheels. Others got lucky and still dyno around 210. Personally, I have not dynoed my car.
However, there is a solution. Canzoomer, a well respected rotary tuner, has released a product that tunes afr and timing in the name of restoring what should have been. In some instances, people have seen even better than what was originally intended for the renesis through simple tuning. Think of it as Hondata.
I was getting ready to purchase this, and lay a baseline dyno, however, Greddy's turbo makes 242 whp on 5 psi. This is on a very small turbo (see www.greddy.com) and on very low boost. Just when I was getting excited about this, ssr engineering released their turbo, and with a more appropriate tune, made 292 whp on similar boost levels. HKS and blitz are also releasing superchargers, and Mazdaspeed has a rumored supercharger in the works. Street porting the renesis although a very simple concept should be left to the pros, but guys (guitarjunkie dave) have been seeing some excellent results.
The car is still an amazing car. 1.3L NA with 238 hp. That's 183 hp/Litre. The old FD made 255 with twin turbos. However, the RX series has never been about pure power, but more about handling dynamics, chassis rigidity, suspension tuning, and adequate power. Remember, compared to the Supra and 300ZX, the FD was also underpowered, but still faster around a track. The RX-8 ties the BMW M3 around top gear's lotus designed track. Thank the 50/50 weight distribution for that, and the amazingly stiff chassis (50% more rigid than the FD with 4 doors and no b-pillar).
So, the car is a victim of the EPA really. I wish they would pick on people like SUV drivers instead.
In short, I think that pnoyster raced an auto 8. I have encountered boosted 7th gens in so. cal and I didn't have a problem putting him behind my rear bumper. Either that or he raced a guy who (like most 8 owners) is still learning about his car's powerband. If you catch an 8 in the wrong gear, it's easy to put him down because of the low torque numbers.
Last edited by nookiemonster; 03-01-2005 at 11:47 PM.
03-01-2005
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Rep Power: 304 Here's some more interesting info regarding the RX-8 and dynos...take it with a grain of salt though. Mazda was pretty sloppy with their frenzied ECU flash to please the EPA.
OFFICIAL MAZDA STATEMENT: SOURCE ROTARY MAGAZINE
Cliffsnotes: The car when being dyno'ed senses that the front wheels are not turning and essentially goes into "safe mode." Even with DSC and TCS turned off it will still sense abnormal engine use, and possible abuse and changes fuel maps and timing to reduce wear on the powertrain and emmisions control systems.
OFFICIAL MAZDA STATEMENT: SOURCE ROTARY MAGAZINE
Statement:
There is no true way to generate flywheel horsepower from a chassis dynamometer because of frictional losses in the driveline, clutch, transmission, differential and tires. Also, variations in testing procedures will cause highly disparate readings: open/closed hood, high/low humidity, high/low ambient temperature, tire pressure, how tightly the car is tied down, which gear the car is tested in, etc.
In addition, we have determined that, in order to prevent damage to the catalytic converter and the entire driveline, when the PCM determines unusual operating parameters such as excessive slip in the drivetrain from the front to the rear wheels, it causes a rich high-RPM mixture and retardation of the timing. All these items combine to cause apparent considerable horsepower loss.
BACKGROUND:
Horsepower Measurement
There is only one true method for measuring engine horsepower: on an engine dynamometer at constant speed and utilizing variable load.
The engine should use the same intake and exhaust system as in the car. HP results must be corrected to SAE J1349 standards as listed below:
77 degrees Fahrenheit
Sea level
0% humidity
Correction factors must be applied to reference the measurements to SAE J1349 standards. Any correction factor beyond 7% is considered invalid.
Chassis Dynamometers
SAE has produced a technical paper (SAE Technical Paper Series 2002-01-0887) that attempts to address the ongoing debate about inertia dyno horsepower versus OEM net horsepower. You can order a copy by visiting their website at www.sae.org -- we have no intentions of getting mired in the middle of this discussion.
Bottom line: If used properly, chassis dynos are great tools to assist with tuning and modifying vehicles. It is impossible to measure the actual flywheel horsepower because there are simply too many variables.
Other issues that are unique to the RX-8:
The RX-8 uses a very advanced engine management system. Besides precisely controlling the operating parameters of the engine, self-preservation (of both the engine and the catalytic converter) is also considered.
The engine management system continuously monitors all engine functions and adjusts accordingly. For example:
Under heavy load acceleration, the timing is retarded and the fuel mixture richened to reduce the likelihood of pre-ignition or spark knock. If spark knock is encountered, a knock sensor senses the condition and further retards the timing. Gradually timing is advanced and fuel mixture leaned after the load is reduced.
A second reason for fuel enrichment is that when timing is retarded, exhaust temperatures increase; a richer mixture lowers the exhaust temperatures and reduces the chances of damaging the catalytic converter.
In real world driving, this all goes unnoticed to the driver and appears seamless with no disruptions to the performance of the engine. The car encounters a load under acceleration but the load quickly diminishes as the car accelerates in each gear.
Operating on a chassis dynamometer, however, creates a completely different environment. Inertia dynos use a known mass that is accelerated to measure torque at the wheels. This is usually done in one gear under heavy load conditions:
Only the rear wheels are turning while the front tires remain stationary.
On cars equipped with DSC with traction control, the difference in speed between the front and rear wheels is sensed and the power is reduced immediately to compensate for what the car senses as excess wheel spin.
If the DSC is turned off, the traction control is disabled but the brake functions of the DSC are still operational.
If the DSC system is completely disabled, this removes the brake functions from the equation, however it does not fully remove the engine management system functions.
The ABS hydraulic unit/control module (HU/CM), or the DSC HU/CM for cars with DSC, determines vehicle speed by comparing the speed of all four wheels. If two are turning and two are stationary, it will still compute a speed but senses that the car is experiencing excessive wheel spin. To protect against engine or catalyst damage:
The engine management system compares the throttle opening, gear selection (determined by engine speed and road speed) charging efficiency and engine coolant temperature to determine the driving condition.
Since the car is under heavy load, in a tall gear (testing is usually performed in third or fourth gear), with a wide throttle position angle (wide open), spark timing is reduced and the fuel mixture is richened to reduce the occurrence of spark knock and to reduce catalytic converter temperatures.
There is no true way to generate flywheel horsepower from a chassis dynamometer because of frictional losses in the driveline, clutch, transmission, differential and tires. Also, variations in testing procedures will cause highly disparate readings: open/closed hood, high/low humidity, high/low ambient temperature, tire pressure, how tightly the car is tied down, which gear the car is tested in, etc.
In addition, we have determined that, in order to prevent damage to the catalytic converter and the entire driveline, when the PCM determines unusual operating parameters such as excessive slip in the drivetrain from the front to the rear wheels, it causes a rich high-RPM mixture and retardation of the timing. All these items combine to cause apparent considerable horsepower loss.
BACKGROUND:
Horsepower Measurement
There is only one true method for measuring engine horsepower: on an engine dynamometer at constant speed and utilizing variable load.
The engine should use the same intake and exhaust system as in the car. HP results must be corrected to SAE J1349 standards as listed below:
77 degrees Fahrenheit
Sea level
0% humidity
Correction factors must be applied to reference the measurements to SAE J1349 standards. Any correction factor beyond 7% is considered invalid.
Chassis Dynamometers
SAE has produced a technical paper (SAE Technical Paper Series 2002-01-0887) that attempts to address the ongoing debate about inertia dyno horsepower versus OEM net horsepower. You can order a copy by visiting their website at www.sae.org -- we have no intentions of getting mired in the middle of this discussion.
Bottom line: If used properly, chassis dynos are great tools to assist with tuning and modifying vehicles. It is impossible to measure the actual flywheel horsepower because there are simply too many variables.
Other issues that are unique to the RX-8:
The RX-8 uses a very advanced engine management system. Besides precisely controlling the operating parameters of the engine, self-preservation (of both the engine and the catalytic converter) is also considered.
The engine management system continuously monitors all engine functions and adjusts accordingly. For example:
Under heavy load acceleration, the timing is retarded and the fuel mixture richened to reduce the likelihood of pre-ignition or spark knock. If spark knock is encountered, a knock sensor senses the condition and further retards the timing. Gradually timing is advanced and fuel mixture leaned after the load is reduced.
A second reason for fuel enrichment is that when timing is retarded, exhaust temperatures increase; a richer mixture lowers the exhaust temperatures and reduces the chances of damaging the catalytic converter.
In real world driving, this all goes unnoticed to the driver and appears seamless with no disruptions to the performance of the engine. The car encounters a load under acceleration but the load quickly diminishes as the car accelerates in each gear.
Operating on a chassis dynamometer, however, creates a completely different environment. Inertia dynos use a known mass that is accelerated to measure torque at the wheels. This is usually done in one gear under heavy load conditions:
Only the rear wheels are turning while the front tires remain stationary.
On cars equipped with DSC with traction control, the difference in speed between the front and rear wheels is sensed and the power is reduced immediately to compensate for what the car senses as excess wheel spin.
If the DSC is turned off, the traction control is disabled but the brake functions of the DSC are still operational.
If the DSC system is completely disabled, this removes the brake functions from the equation, however it does not fully remove the engine management system functions.
The ABS hydraulic unit/control module (HU/CM), or the DSC HU/CM for cars with DSC, determines vehicle speed by comparing the speed of all four wheels. If two are turning and two are stationary, it will still compute a speed but senses that the car is experiencing excessive wheel spin. To protect against engine or catalyst damage:
The engine management system compares the throttle opening, gear selection (determined by engine speed and road speed) charging efficiency and engine coolant temperature to determine the driving condition.
Since the car is under heavy load, in a tall gear (testing is usually performed in third or fourth gear), with a wide throttle position angle (wide open), spark timing is reduced and the fuel mixture is richened to reduce the occurrence of spark knock and to reduce catalytic converter temperatures.
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