RX-8 is the car to OWN.
Alot of magazines say, while your driving it.. the numbers.. dyno charts... just vanish away.

K&N Intake adds 12 hp(some on forum has on, and has dyno charts)
Borla Exhaust adde 8 hp(some on forum has, and has dyno charts)
ECU upgrade adds 20-30 hp(canzoomer's ecu upgrade stage I)

Mod will come, and aftermarket support is on its way... Greedy and HKS said they will donw the future build turbo for the rx-8.. wait 6-12 months.

 

What's the deal here? Did Mazda change the ECU to comply with emissions requirements? If so, is the ECU mod legal?

 

I can't wait to get my 8 and I strongly suggest a test drive. I warn you though, it wasn't till I drove one for the 3rd time that I actually took the RPM's up there. The first two times I was very dissappointed but once I let it rev up the thing can move.

On the other hand, if you want extreme acceleration on a budget find a used late model Z28 or Trans AM. You can pick one up with low miles for low $20k's(Coupe). We bought one new for $26k and have put about $1200 into the intake and exhaust. The car has responded extremely well and we're up above 375hp. Also, you should know some of the '01 and '02 F-Bodies have an LS-6 block and they all have the LS-6 intake manifold. (LS-6 is the Corvette Z06 engine, stock 405hp) We're going to put about another $3-4.5k into ported, polished LS-6 racing heads and cams which will give us a complete LS-6. Others with a similar setup have gotten over 500hp. Wanna spend another few grand? Turbo that thing and you can churn out as much as 650hp.

Also, with only a few mods to the intake we ran the car and it broke 13 seconds in the 1/4.

But since this is an RX-8 forum I will continue to push for the 8... it's a fantastic car... :D

 

wow...I didn't know those simple mods add so much for the 8...crap...that means I'm gonna have to sell the S......

 

The A/T shares the same compression ratio as the M/T. The difference is that it has 4 ports instead of 6 ports.

Various people were commenting that the ports flow a little smoother in the A/T as opposed to the M/T, which should be more effective for Forced Induction.

I'm going by this principal as to why the A/T would respond better to forced induction as opposed to the M/T...IT NEEDS IT MORE :p

 

The G35's respond damn well to nitrous as well. Seen figures of something around 310 WHP on a mildly jetted setup on 91 Octane fuel.

 

Hes interested in stage II this adds 45 to 55 hp and its been tested with testpipe so far adding I think it was 52 whp.

That brings us to 232 whp with just ecu and midpipe. We also have a very huge weight advantage on the Z. This is just awsome imho. Then wait for a good intake system to come out and some headers and exhaust. That is just the surface of what can be done with the RX8 and your already at a minimum of 252 whp (our cars really love to breathe so I MIGHT be a little conservative here).

Im sure you will suprise more than a few Z and G35 owners hehe and wont that be fun!

 

Ok, thanks for clarifying.

 

Does anyone have any idea why Mazda detuned this engine so much? It is obviously capable of so much more.

I read in Car and Driver it was because they needed to meet US fuel efficiency requirements. That makes no sense, because the car is getting much lower gas mileage than the sticker says.

It also can't be emissions because running rich and wasting gas will not decrease emissions.

WTF? Did Mazda just want to see if they could sell a detuned version with **** poor gas mileage in the states? Well, they obviously can.

It seems like some kind of joke. As if the Japanese are laughing at all the silly Americans in their 15 second RX-8's and filling up every couple of days. Well, the joke's over.

Give us our hp and mpg back, you bastards!

 

Running rich will increase the life of the cat however, which is an emissions issue.

 

It will increase the life, but isn't that because it won't be doing it's job as well, which puts more pullutants into the air.

 

This has been well and thoroughly documented on this forum - we know exactly why Mazda detuned this engine.

It is for emissions related reasons - not that the output of pollutants from the tailpipe needed amending, but that new for 2004 US regulations require emissions control equipment to survive a life of 120K miles without requiring replacement (previous was something like 50K or 70K miles). Mazda, late in the testing routines, found that their initial tune would make it doubtful that the required catalytic converter life would be met - they had to cobble together a revised ECU map with richer mixture at high load and high RPM, which lowers the exhaust temperature, which directly results in longer catalytic converter life. Note that the high rpm high load condition isn't even part of any emissions testing program.

End result - you can't have it back from Mazda. They can't meet cat converter durability requirements with a leaner mixture.

Regards,
Gordon

 

OK, thanks. I have searched through here plenty of times, and asked a few times as well, and this is the first straight answer I have found or received.

That actually makes sense. It is an insanely stupid regulation though. A difference of 4mpg (I am using 16 vs 20) over 120k miles, would be about 1500 gallons of gasoline wasted. How many cats can you replace with the cost of 1500 gallons of gasoline?

Can you point me to the original post? It's probably one of those things right in front of your face that you never see.

 

Couldn't Mazda just run two cats? I read somewhere that the WRX has three.

 

I thought the RX-8 did have 2 cats, and adding another cat will further decrease HP.

 

Does anyone know? Adding another cat in series would decrease HP, and it probably wouldn't help that much in terms of the life of the first one anyway.

However, I am talking about adding one in parallel, which would increase HP. It would require a dual exhaust pre-cat, which is why Mazda would need another production year to make that kind of a change.

But even so, the increase in HP from a more free flowing exhaust is not the point. The increase would be from the fuel maps that Mazda would now be able to run without worrying about cat life.

 

I searched and there are two.

I am still almost willing to bet money that this is exactly what Mazda does.

The 2004 models will have 247hp, and Mazda will claim it is because they've add a true dual exhaust, when actually just allowed them to legally run better fuel maps.

Unfortunately, it will cost more.

 

Current models are 2004, and don't hold your breath.

 

I took my '91 MR2 Turbo's stock tubing and cat out. I plumbed it with 3" diameter tubing and a stock Mustang V8 cat (with some interesting engineering) and wallah... If the cats were larger and the tubing expanded the car would breath better ie., more hp! Keeping a cars cat cooler by dumping more fuel into the mixture is not the way to save the enviroment. High temps kill cats no matter how you look at it and for the government to insist that we waste fuel, if that is what it takes, to keep a cat alive for 120k that is assinign. Bigger headers, cat backs, and cats to offer less backflow pressure is the answer especially for those of us who intend to turbo our babies once Mazdaspeed has it to offer. I wonder if there is an enviromental group out there willing to argue this case and actually do some good for the planet (and our beautiful cars as well).

 

Don't blame the government, blame Mazda, they're the ones that came up with the quick fix, they should have seen the problem before the car went into production.

 

To the EPA:
OK let's say that I am an EPA officer and it is my job to overlook car manufacturers to see that they are being "earth friendly" should I not pay attention to the fact that a particular company is wasting resources and causing more problems to save a $300 part? (price was a guess any dealer can step in and fill in the correct price). 120k is aproximately 8 years and their are many more expensive parts that will be left along the roadside long before then.

To the manufacturer:
Wasting fuel to save a $300 part, ie. the catalytic converter, that could be saved with better engineering is not acceptable. Customers who will be buying autos for years to come are evaluating you everyday based on how you solve your engineering problems. MPG are important to many of the people out there and the enviroment is also an important issue. Cutting corners to deal with lower octane in the North American market is absolutely unacceptable. It doesn't matter whether it is lower octane or higher cat. converter standards it all amounts to your customers lowered mpg and hp. Fix it.

 

I am one of the biggest Mazda fans out there. But this is my point exactly, and I am pretty pissed about it.

I really wanted an RX-8, and even though I was disappointed by the performance and horrified of the gas mileage, I was still considering buying one until I found out the real reason Mazda "fixed" the car.

I wrote a letter to Car and Driver about it. We'll see if they put it in March's issue. Probably not, but I figured I would give it a shot.

 

Write to your congressman...

 

To the EPA:
OK let's say that I am an EPA officer and it is my job to overlook car manufacturers to see that they are being "earth friendly" should I not pay attention to the fact that a particular company is wasting resources and causing more problems to save a $300 part? (price was a guess any dealer can step in and fill in the correct price). 120k is aproximately 8 years and their are many more expensive parts that will be left along the roadside long before then.


I doubt that being "earth friendly" is a part of EPA bureaucrats job description.