4th gen ND Mazda MX-5 Miata

[NoHaveMSG]

Originally Posted by daiheadjai

Actually I'd be curious to see the effect of aftermarket headers people run on emissions and fuel consumption.

I don't notice any change in fuel consumption on my car. Running catless header, and front pipe with high flow cat.

[nikitopo]

Originally Posted by mav1178

But you can't talk sense about fuel consumption and emissions targets to a bunch of enthusiasts that take out the cat, make more power, and don't want to deal with stupid things like smog checks and federal emissions laws!

So of course it's an engineering flaw! Why else would that stupid thing be there for no reason!

Originally Posted by daiheadjai

Actually I'd be curious to see the effect of aftermarket headers people run on emissions and fuel consumption.

It depends if you want to cheat or not. If not they'll just fail the test. Why do you think they put a piece of metal if it was not absolutely necessary? A catless header should be for racing use ONLY. Everything else is about pretending to be ethical and not obeying the laws. And of course we are also pretending that we are car enthusiasts by removing just a cat. Why don't we do other things like buying the new factory header, doing weight reduction or in general try other approaches that don't have any impact on the regulations? Because it is not that easy or it is more expensive? Then we are not really car enthusiasts. And I don't buy the argument that it is OK a 5% or less of enthusiasts to go catless, because there is not so much impact. It is like sticking the finger to the rest of the people out their who obey the laws and respect the others.

[fatoni]

Originally Posted by Yoshoobaroo

Right.

I fixed variables for a fair comparison. Both metal roof versions, both top trim pre-facelift weight numbers, since we don't know the weight of the new Miata. And the dyno numbers are both from the same indoor dyno, the best comparison you're going to get.


Sent from my iPhone using Tapatalk

Why the rf and not the soft top? Seems like samdbagging to me

[mav1178]

Originally Posted by daiheadjai

Actually I'd be curious to see the effect of aftermarket headers people run on emissions and fuel consumption.

you'd need a large enough sample size to see results, and they all need to be in controlled test environments.

Then you'd need an engine tune that produces the correct amount of residual O2 in the exhaust stream, to maximize the conversion process.

There's a reason why people throw CEL when running a catless header, because it means the exhaust stream is too lean or too rich (and thus the conversion process of CO and NOx is not optimal or nonexistant because the catalytic converter is gone).

I would be curious too, except no engine tuner out there that tunes for performance does it with a smog test machine mounted on the tailpipe. Once you factor in the cost of that type of test, a typical engine tune would probably cost $5000 or more unless you get enough people to test.

Even then, you still have to deal with the legality of it. Even in states without smog checks, it is still a federal crime to remove a catalytic converter for use on a public street.

Smog tests aren't to prevent individuals from modding their cars, it's to push the rest of the vehicle driving public towards a standard of tailpipe emissions to improve air quality. Take the new Toyota Camry for example, it is now running 0W-16 weight synthetic oil in the 4 cylinder cars. It's a new mix that's been running in Japan for a while, but they've now introduced it to the US. 4 weights lower doesn't sound like much, but (according to Toyota) it translates to about a 1.5% to 2% fuel economy improvement.... one car is not measurable, but considering there's 300,000+ Camrys sold every year, that translates to a pretty big change in fuel consumption and emissions every year.

Fun stuff.

[why?]

Originally Posted by nikitopo

It depends if you want to cheat or not. If not they'll just fail the test. Why do you think they put a piece of metal if it was not absolutely necessary? A catless header should be for racing use ONLY. Everything else is about pretending to be ethical and not obeying the laws. And of course we are also pretending that we are car enthusiasts by removing just a cat. Why don't we do other things like buying the new factory header, doing weight reduction or in general try other approaches that don't have any impact on the regulations? Because it is not that easy or it is more expensive? Then we are not really car enthusiasts. And I don't buy the argument that it is OK a 5% or less of enthusiasts to go catless, because there is not so much impact. It is like sticking the finger to the rest of the people out their who obey the laws and respect the others.

The "laws" are unethical and completely useless. The only things these moronic laws do is add cost and complexity to autos, they do literally nothing else. Cats are old useless technology on today's modern vehicles.

They could easily change the laws in a way that would get rid of useless evil tech and yet also make the air better. A government bureaucrat is never someone that should make any decision on anything anywhere. I guarantee the automakers could find much better and less expensive solutions for everything without evil government interference. The only thing government bureaucrats could ever do to make the world a better place is close the government forever and quit.

[fatoni]

Originally Posted by why?

The "laws" are unethical and completely useless. The only things these moronic laws do is add cost and complexity to autos, they do literally nothing else. Cats are old useless technology on today's modern vehicles.

They could easily change the laws in a way that would get rid of useless evil tech and yet also make the air better. A government bureaucrat is never someone that should make any decision on anything anywhere. I guarantee the automakers could find much better and less expensive solutions for everything without evil government interference. The only thing government bureaucrats could ever do to make the world a better place is close the government forever and quit.

Google what Los Angeles looked like before things like carb and Google how much hp the mustang had before that damned fuel injection became mandated. Not saying there aren't better ways but to say nothing comes from regulation is simply wrong.

[wbradley]

Originally Posted by fatoni

Google what Los Angeles looked like before things like carb and Google how much hp the mustang had before that damned fuel injection became mandated. Not saying there aren't better ways but to say nothing comes from regulation is simply wrong.

Some people are so far to the right that they think everyone should have their very own country. So the private sector will fix things when it goes back to this?
Please...

[mav1178]

Originally Posted by why?

Cats are old useless technology on today's modern vehicles.

So what is a modern technology that is better and less costly than a catalytic converter to reduce NOx and CO emissions out of a car?

[mav1178]

Originally Posted by fatoni

Google what Los Angeles looked like before things like carb and Google how much hp the mustang had before that damned fuel injection became mandated. Not saying there aren't better ways but to say nothing comes from regulation is simply wrong.

Yup.

I'm in Taipei right now... people should come visit in the summer when the scooters are all over the place and enjoy the awesome air quality they have here.

[krayzie]

The air quality is something I don't miss from living in Hong Kong.

Also seen that LA skyline from the observatory in 2000 SMFH.

[Lantanafrs2]

The world is flat. Computers are a fad. There will always be a need for carburetors.

[NoHaveMSG]

Originally Posted by why?

The "laws" are unethical and completely useless. The only things these moronic laws do is add cost and complexity to autos, they do literally nothing else. Cats are old useless technology on today's modern vehicles.

They could easily change the laws in a way that would get rid of useless evil tech and yet also make the air better. A government bureaucrat is never someone that should make any decision on anything anywhere. I guarantee the automakers could find much better and less expensive solutions for everything without evil government interference. The only thing government bureaucrats could ever do to make the world a better place is close the government forever and quit.

Ever see what the inside of a modern big rig exhaust looks like? Freightliner drove one from Mt Holly, NC to OR to show the company my father just retired from, the exhaust tips were clean. Since he started there from the time he retired truck fuel mileage also nearly doubled.

[mrg666]

Originally Posted by nikitopo

They put already resources and money on a new header. It is the one that comes with the '+17 MT cars, but their purpose wasn't really to fix the torque dip. They wanted mainly to give more power on the higher end range.

For reasons that I cannot install a catless header in Germany, I ordered and installed their new header. I was testing lately acceleration numbers and comparing them with a stock first generation car. Overall, together with other changes and weight reduction the times is like having now a 240hp NA car (*).

So, don't underestimate what they did with the new header. People saying that the new header is giving maximum 2-3hp, they don't know what they are talking about or cannot afford it and they are just jealous.


(*) I even made the assumption that the first cars were actually 190hp cars and not really 200hp cars. Catalog power was a bit overestimated.

240 hp? Give me a break, please. You keep repeating these power gain claims. How hard it is to go get a dyno and provide proof? 2017 model got only 5hp extra with several other changes combined in addition to header. We don't even know if header itself is making any change by itself. Either provide the proof or just keep posting and I will keep calling this .

[wparsons]

Originally Posted by mrg666

240 hp? Give me a break, please. You keep repeating these power gain claims. How hard it is to go get a dyno and provide proof? 2017 model got only 5hp extra with several other changes combined in addition to header. We don't even know if header itself is making any change by itself. Either provide the proof or just keep posting and I will keep calling this .

If you read his post closer you'll see that he's saying that the power increase + weight reduction makes his car feel like a stock weight car with 240hp, not a claim that he's actually making 240hp.

As for the 2017+ cars, they dyno'd at more like 10-15whp over stock 2013-2016 cars. Realistically the early cars were more like 190hp, and the 2017+ are a more accurate 205hp.