At 34,000 miles my car suddely came alive
10-03-2005 | 07:14 PM
#26
Go Texas Longhorns!
Joined: Apr 2003
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From: Houston, Texas
its pretty much a fact that rotary's get stronger over time. I can tell a difference at 18K vs 5K. That said, its not going to feel like a switch went off. I would like to see a dyno of a car with 40K, just for ***** and grins.
10-03-2005 | 07:18 PM
#27
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From: GW's old stomping ground
Originally Posted by Gambit
haha...I know what you mean...i've had mine for a year now and only put 8k on it
10-04-2005 | 06:07 PM
#29
Lubricious
Joined: Oct 2003
Posts: 3,425
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From: SF Bay Area, California
Originally Posted by zoom44
actually not then either. for this thread i thought we could get past the racing remark and discuss why at 34k he is suddenly chirping his tires.
Seriously - I hear lots of talk of the engine getting stronger as it ages. I've got just over 10K and it does seem to rev a bit more freely but then again I'm on my 3rd flash. Oh, well, maybe this was the oft-mentioned "20,000 mile cutover" rumored to be in the ECU... It's all good
10-05-2005 | 01:50 PM
#32
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From: Olathe, KS
Originally Posted by neit_jnf
wasting your time with a civic??
10-05-2005 | 01:52 PM
#33
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From: Olathe, KS
Originally Posted by Nubo
Umm.. because the tires are worn out? It's easier to chirp when you're running on the belts
Originally Posted by SHOWOFF
Brand new shoes Falken FK451 GRB's. They even hook better than the new Nitto's they replaced. Wider too.
10-05-2005 | 02:21 PM
#34
Oil Injection
Joined: Feb 2005
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From: Orlando, FL
Didnt the RX7 have a similar change in performance at some point, 30k miles or something?
I thought that there was a service at XXX miles, and among other things they changed some setting in the ECU that gave better performance.
I thought that there was a service at XXX miles, and among other things they changed some setting in the ECU that gave better performance.
10-05-2005 | 06:48 PM
#36
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From: Philly
EPA2 original requirement was for the catalytic converter life to last 80K miles. EPA3, the current guideline, mandates that the cat last for 120K miles. It just make sense that at 40K (120K-80K=40K) miles the fuel mixture leans out to what the RX-8 was originally designed, thus the added horsepower. See this documented case in C&D here.
Why Mazda overlooked the new EPA mandate, I don't know. Perhaps there was a point of no return in the design work of the RX-8, where the work around was the only cost effective solution.
Ford was giving Mazda a hard-time with the return of the rotary engine since the nightmare of the RX-7 twin turbo in the early 90s, and the obstacles with emissions that continuously plagued the rotary. Also, nearly all the majors race events have banned the rotary from competition because it would dominate from its greatest advantages, higher horsepower to weight ratios and better reliability. Le Man immediately banned the rotary the first year it won. Simply "no props" for further rotary development.
That's why there was a huge problem with lower HP ratings with the RX-8 first debut, richer fuel mixtures reduces horsepower, but conserve cat life since it was not being depleted of ions (platinum, rhodium and/or palladium) for carbon monoxide, VOCs and NOx molecules conversion from "normal" engine waste gas. The exhaust was too rich with unburned gas for that to happen.
Believe what you must
Why Mazda overlooked the new EPA mandate, I don't know. Perhaps there was a point of no return in the design work of the RX-8, where the work around was the only cost effective solution.
Ford was giving Mazda a hard-time with the return of the rotary engine since the nightmare of the RX-7 twin turbo in the early 90s, and the obstacles with emissions that continuously plagued the rotary. Also, nearly all the majors race events have banned the rotary from competition because it would dominate from its greatest advantages, higher horsepower to weight ratios and better reliability. Le Man immediately banned the rotary the first year it won. Simply "no props" for further rotary development.
That's why there was a huge problem with lower HP ratings with the RX-8 first debut, richer fuel mixtures reduces horsepower, but conserve cat life since it was not being depleted of ions (platinum, rhodium and/or palladium) for carbon monoxide, VOCs and NOx molecules conversion from "normal" engine waste gas. The exhaust was too rich with unburned gas for that to happen.
Believe what you must
Last edited by Slick8; 10-05-2005 at 08:46 PM.
10-05-2005 | 08:28 PM
#37
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From: Florida
32 k miles here and definitely more grunt, the back end DOES kick out on the 1-2 shift and a significant (heard by my friend on the phone) chirp on the 2-3 shift.
The exhaust tips stay CLEAN now. I used to have to clean them every night during my nightly california duster procedure, but, I have to say, not anymore.
One more proof this thing is running better at 32k miles - I just got 20.09 miles per gallon driving the very same route that I have been for the past two years (back and forth to work) and I originally (two years ago ) start at 17 mpg and got improvements over time attributable to each flash and rotary break-in, but I had always come up just shy of 20 mpg, well that all changed Yesterday!
So, at 32k miles, more power, clean exhaust tips and better mileage!
The exhaust tips stay CLEAN now. I used to have to clean them every night during my nightly california duster procedure, but, I have to say, not anymore.
One more proof this thing is running better at 32k miles - I just got 20.09 miles per gallon driving the very same route that I have been for the past two years (back and forth to work) and I originally (two years ago ) start at 17 mpg and got improvements over time attributable to each flash and rotary break-in, but I had always come up just shy of 20 mpg, well that all changed Yesterday!
So, at 32k miles, more power, clean exhaust tips and better mileage!
10-06-2005 | 03:07 AM
#39
The game changer!
Joined: Oct 2002
Posts: 298
Likes: 1
From: Tx
Originally Posted by Raptor2k
Lol, this certainly makes me jealous of my low miles. About a year and a half or two for me to go!
Tell me about it. It seams that the higher mileage ones will be the more desirable ones in the long run. LOL Hell the used Rx8's might start going up in value.
10-06-2005 | 09:19 AM
#41
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Joined: Feb 2005
Posts: 882
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From: Winston-Salem, NC
Originally Posted by Slick8
EPA2 original requirement was for the catalytic converter life to last 80K miles. EPA3, the current guideline, mandates that the cat last for 120K miles. It just make sense that at 40K (120K-80K=40K) miles the fuel mixture leans out to what the RX-8 was originally designed, thus the added horsepower. See this documented case in C&D here.
Why Mazda overlooked the new EPA mandate, I don't know. Perhaps there was a point of no return in the design work of the RX-8, where the work around was the only cost effective solution.
Ford was giving Mazda a hard-time with the return of the rotary engine since the nightmare of the RX-7 twin turbo in the early 90s, and the obstacles with emissions that continuously plagued the rotary. Also, nearly all the majors race events have banned the rotary from competition because it would dominate from its greatest advantages, higher horsepower to weight ratios and better reliability. Le Man immediately banned the rotary the first year it won. Simply "no props" for further rotary development.
That's why there was a huge problem with lower HP ratings with the RX-8 first debut, richer fuel mixtures reduces horsepower, but conserve cat life since it was not being depleted of ions (platinum, rhodium and/or palladium) for carbon monoxide, VOCs and NOx molecules conversion from "normal" engine waste gas. The exhaust was too rich with unburned gas for that to happen.
Believe what you must
Why Mazda overlooked the new EPA mandate, I don't know. Perhaps there was a point of no return in the design work of the RX-8, where the work around was the only cost effective solution.
Ford was giving Mazda a hard-time with the return of the rotary engine since the nightmare of the RX-7 twin turbo in the early 90s, and the obstacles with emissions that continuously plagued the rotary. Also, nearly all the majors race events have banned the rotary from competition because it would dominate from its greatest advantages, higher horsepower to weight ratios and better reliability. Le Man immediately banned the rotary the first year it won. Simply "no props" for further rotary development.
That's why there was a huge problem with lower HP ratings with the RX-8 first debut, richer fuel mixtures reduces horsepower, but conserve cat life since it was not being depleted of ions (platinum, rhodium and/or palladium) for carbon monoxide, VOCs and NOx molecules conversion from "normal" engine waste gas. The exhaust was too rich with unburned gas for that to happen.
Believe what you must Also, you have to rethink your theory a little, just because 120k - 80k = 40k, the cat already has those 40k miles of use under them, so if the car was programmed to start running leaner at 40k, the cat would not be new and probably still wouldn't last to 120k, sorry doesn't add up.
I believe that the rotary starts to finally loosen up around 30k, and that with a cooler less humid temps coming around the corner this time of year the car is just feeling stronger because it has cooler air to work with.
10-06-2005 | 01:21 PM
#42
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From: Philly
Brice-RX8 banter, aka chickenlittle:
Also, you have to rethink your theory a little, just because 120k - 80k = 40k, the cat already has those 40k miles of use under them, so if the car was programmed to start running leaner at 40k, the cat would not be new and probably still wouldn't last to 120k, sorry doesn't add up.
Also, you have to rethink your theory a little, just because 120k - 80k = 40k, the cat already has those 40k miles of use under them, so if the car was programmed to start running leaner at 40k, the cat would not be new and probably still wouldn't last to 120k, sorry doesn't add up.
Slick8 hypothesis:
That's why there was a huge problem with lower HP ratings with the RX-8 first debut, richer fuel mixtures reduces horsepower, but conserves cat life since it was not being depleted of ions (platinum, rhodium and/or palladium) for carbon monoxide, VOCs and NOx molecules conversion from "normal" engine waste gas. The exhaust was too rich with unburned gas for that to happen.
That's why there was a huge problem with lower HP ratings with the RX-8 first debut, richer fuel mixtures reduces horsepower, but conserves cat life since it was not being depleted of ions (platinum, rhodium and/or palladium) for carbon monoxide, VOCs and NOx molecules conversion from "normal" engine waste gas. The exhaust was too rich with unburned gas for that to happen.
Also, it would be a major upset in equilibrium if the ECU remaps the fuel air mixture instantaneously, it is a gradual change, probably set near the proximity of 34,000 miles or earlier. A little more complex than my simplified example.
It makes perfect chemical engineering sense to me
Last edited by Slick8; 10-06-2005 at 01:30 PM.
10-06-2005 | 02:48 PM
#43
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Joined: Feb 2005
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From: Winston-Salem, NC
I think I understand what you are saying Slick, and like the idea, but do you really think that Mazda went to the trouble of establishing a mileage determined mapping change within the ECU? I know that the ECU in our cars are pretty complex but just not sure if they would go to such trouble.
On a side note, if what you are saying somehow turns out to be true, I can't wait because my car feels great now at 22k, I can only imagine 15k from now!!
On a side note, if what you are saying somehow turns out to be true, I can't wait because my car feels great now at 22k, I can only imagine 15k from now!!
10-06-2005 | 03:52 PM
#44
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From: Philly
I think I understand what you are saying Slick, and like the idea, but do you really think that Mazda went to the trouble of establishing a mileage determined mapping change within the ECU? I know that the ECU in our cars are pretty complex but just not sure if they would go to such trouble.
10-06-2005 | 04:08 PM
#45
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From: Philly
Looks like someone else on the forum can confirm this hypothesis:
Gord96BRG 6/9/2004:
The missing HP have been well documented here - the problem is that the US, for 2004, extended the catalytic converter life requirements from 100K miles to 120K miles. In durability testing of the original 247 hp ECU tune, Mazda found that the exhaust gas temperature at high load and high rpm was too high, and that the catalytic converters would likely not last the required 120K miles. To remedy this, they richened the mixture at high rpm high load conditions to lower the exhaust gas temperature, with the byproduct that the peak HP dropped (to no more than 238).
The missing HP have been well documented here - the problem is that the US, for 2004, extended the catalytic converter life requirements from 100K miles to 120K miles. In durability testing of the original 247 hp ECU tune, Mazda found that the exhaust gas temperature at high load and high rpm was too high, and that the catalytic converters would likely not last the required 120K miles. To remedy this, they richened the mixture at high rpm high load conditions to lower the exhaust gas temperature, with the byproduct that the peak HP dropped (to no more than 238).
10-06-2005 | 04:16 PM
#46
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From: Winston-Salem, NC
Originally Posted by trhoads
I am at almost 36k, in less than 2 years. While my car feels very good now, I attribute it to the re-flashes, and the modifications that have been made. Does my car chirp tires, no, only once, and that was with DSC off. I can't imagine that it would just change overnight. But if you are happier now, I guess you can't complain about that.
10-06-2005 | 04:18 PM
#47
Music and Cars!!! :)
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Well, if anything can be learned from this it's that people should start driving their rx8s instead of admiring them and their low odometer reading. Start taking them to work, and on long trips, and use the beater car for 100% winter use, nothing else.
10-06-2005 | 05:18 PM
#49
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From: Winston-Salem, NC
Originally Posted by Slick8
Looks like someone else on the forum can confirm this hypothesis:
Quote:
Gord96BRG 6/9/2004:
The missing HP have been well documented here - the problem is that the US, for 2004, extended the catalytic converter life requirements from 100K miles to 120K miles. In durability testing of the original 247 hp ECU tune, Mazda found that the exhaust gas temperature at high load and high rpm was too high, and that the catalytic converters would likely not last the required 120K miles. To remedy this, they richened the mixture at high rpm high load conditions to lower the exhaust gas temperature, with the byproduct that the peak HP dropped (to no more than 238).
Quote:
Gord96BRG 6/9/2004:
The missing HP have been well documented here - the problem is that the US, for 2004, extended the catalytic converter life requirements from 100K miles to 120K miles. In durability testing of the original 247 hp ECU tune, Mazda found that the exhaust gas temperature at high load and high rpm was too high, and that the catalytic converters would likely not last the required 120K miles. To remedy this, they richened the mixture at high rpm high load conditions to lower the exhaust gas temperature, with the byproduct that the peak HP dropped (to no more than 238).
Anyone close to Mazda, know anything about this.