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pdz
08-28-2003, 07:49 AM
this is the second time Mazda has screwed up its power ratings (remember the 160hp miata that is actually 142hp?):

http://www.autoweek.com/cat_content.mv?port_code=autoweek&cat_code=carnews&loc_code=index&content_code=00435633

and ford had that debacle with the prior generation SVT cobras.

does anyone know if BMW has ever had this problem? i know porsche is really bad at overrating its engines, too. the M64 (993 engines) were really overrated and the M96 (996 engines) are overrated, too, when it comes to dyno time.

Ack
08-28-2003, 07:56 AM
"Mazda officials say after modifying the carís powertrain control module to meet required federal emissions standards, the RX-8 with manual transmission is producing 238 hp, down from the promised 247 hp, while the automatic- trans model is down 10 hp to 197 hp. Mazda says the drop in power doesnít affect the carís 0-to-60-mph times, however." :rolleyes:

Hm, one lie straight into another one. Doesn't affect 0-60 times. :lmao:

JST
08-28-2003, 07:59 AM
this is the second time Mazda has screwed up its power ratings (remember the 160hp miata that is actually 142hp?):

http://www.autoweek.com/cat_content.mv?port_code=autoweek&cat_code=carnews&loc_code=index&content_code=00435633

and ford had that debacle with the prior generation SVT cobras.

does anyone know if BMW has ever had this problem? i know porsche is really bad at overrating its engines, too. the M64 (993 engines) were really overrated and the M96 (996 engines) are overrated, too, when it comes to dyno time.


If anything, recent BMW engines appear to be somewhat underrated. Part of this comes from the fact that BMW has been tuning its engines for "under the curve" power rather than peak power, which yields substantial performance benefits. How else can a 3200 lb, 225 hp vehicle post 0-60 times in 6 seconds dead? Or a 3200lb, 240 hp car do it in 5 and a half (the old M3)? But beyond the philosophy of maximizing useful power, it's my impression that BMW dyno results tend to show that either a) BMW's have remarkably efficient drivelines that result in less parasitic loss than other cars, or b) BMW is hedging a bit on the peak power produced by its engines.

Hercules
08-28-2003, 08:13 AM
I got a letter from Mazda about that... they offered me $500, and free maintenence for the next four years, or I could return the car and they'd buy it back.

I am opting for the former. Just because a few numbers have changed doesn't make it less fun to drive :) I am still enjoying it thoroughly.

pdz
08-28-2003, 08:55 AM
I got a letter from Mazda about that... they offered me $500, and free maintenence for the next four years, or I could return the car and they'd buy it back.

I am opting for the former. Just because a few numbers have changed doesn't make it less fun to drive :) I am still enjoying it thoroughly.

relatively speaking, this power issue with the RX-8 is less significant than the miata power issue. but it's still an oversight.

i know manufacturing is complicated, but it IS a japanese company after all. i guess that if anything, i would have expected this in a german company before a japanese company because of arrogance.

Mr. The Edge
08-28-2003, 08:59 AM
Isn't Dinan claiming that their M5 upgrade isn't making the power they're advertising because BMW's numbers are overstated?

pdz
08-28-2003, 09:52 AM
Isn't Dinan claiming that their M5 upgrade isn't making the power they're advertising because BMW's numbers are overstated?

wow.

i didn't know that.

i knew that the strange thing about the M5 is that they use stock 540 headers and those do not flow well at all. (540 owners: hello? buy dinan headers!). interesting how they would cheap out like that, but i didn't know the engines were down on power, too.

hard to believe, but maybe?

pdz
08-28-2003, 09:58 AM
here is a little link about how down on power some 996s are:

http://www.technodyneracing.com/technodyne1/articles.html

scroll down to the 996 racing car section. i know firsthand and have seen some dyno sessions with 993 engines and there tends to be a lot of variation in power (not good variations).

but the first generation 996 engines are far worse. it's not clear that the 3.6litre iterations of the M96 are any better (or leak any less).

Mr. The Edge
08-28-2003, 10:04 AM
wow.

i didn't know that.

i knew that the strange thing about the M5 is that they use stock 540 headers and those do not flow well at all. (540 owners: hello? buy dinan headers!). interesting how they would cheap out like that, but i didn't know the engines were down on power, too.

hard to believe, but maybe?

Actually I think that most conjecture is that Dinan is full of bull...

Jeff_DML
08-28-2003, 11:10 AM
I got a letter from Mazda about that... they offered me $500, and free maintenence for the next four years, or I could return the car and they'd buy it back.

I am opting for the former. Just because a few numbers have changed doesn't make it less fun to drive :) I am still enjoying it thoroughly.

Hey hercules, are you going to write a review and post some pics of your RX-8? :thumbup:

pdz
08-28-2003, 11:59 AM
Actually I think that most conjecture is that Dinan is full of bull...

i disagree, slightly.

i think he (steve dinan) is the first to tell anyone who is listening that the dynographs he presents are based on n=1 and that it's only under optimal conditions, with the OBD2 reset and high octane fuel with an engine not heat soaked that you see the power they say they put out.

and this is well-documented in interviews with him in Roundel, Car & Driver and Automobile. other people only admit these things begrudgingly, if at all.

and remember, their corporate philosophy means that their engines with their add-on's will go at least 100,000 miles. that's better than anyone else in terms of testing; and his status as a "manufacturer" also means that there are such things as certified pre-owned Dinan vehicles for sale at BMW dealerships. this is tolerated because he has credibility.

i see both sides of the Dinan issue. it's boutique stuff, but often the prices are 'slightly' justified by their superior R&D. and i speak from personal experience with their blower kit; i never had any of the issues that people have with esstuning, RMS or anyone else with my kit.

bimmerpunk
08-28-2003, 01:36 PM
I got a letter from Mazda about that... they offered me $500, and free maintenence for the next four years, or I could return the car and they'd buy it back.

I am opting for the former. Just because a few numbers have changed doesn't make it less fun to drive :) I am still enjoying it thoroughly.

Did Mazda offer to pay full price for the car (ie. what you paid for it) Or are they paying for the current value of it as a used car. If its the former, you would probably be able to sell it to mazda and buy a new one now that the prices are going down.

But I guess that it is highly unlikely that they will pay full price for the car, reguardless of the error

variable42
08-28-2003, 03:19 PM
Actually I think that most conjecture is that Dinan is full of bull...

Agreed. Over the last couple years, as I've gotten to know Dinan's products better, I've lost all respect for them as a company.

The Roadstergal
08-29-2003, 09:48 AM
Hm, one lie straight into another one. Doesn't affect 0-60 times. :lmao:

0-60 times are tested, not determined on the basis of hp. :confused:

pdz
08-29-2003, 01:52 PM
0-60 times are tested, not determined on the basis of hp. :confused:

they were probably conservative enough with their reported 0-60mph times to give themselves enough room to cover their butts.

we want a driving report, herc. especially compared to a 330.