[WoodinvilleDan]

I just saw your video there! Nice handling, and wow when you were braking at the end the tail wanted to come around in the wet.

Ya, it was a blast, ranked 22 out of 80 cars, informal event without proper classing, felt amazing (74 of the cars are faster than mine on paper).
In the wet is the only time I experience lift off oversteer.
Have you experienced that, as I think you're running an RSB on stiff setting right?

 

[TalonTsi90]

The fun event last week had me experimenting with getting the rear to rotate on demand going into a corner and being able to be on the power sooner. The vid i posted in the thread shows this on the back end of the course, especially the last corner before the finish. You brake slightly before normal, turn as you lift off the brakes and onto the gas while it rotates for you. So. Much. Fun.

 

[meishungry]

Ya, it was a blast, ranked 22 out of 80 cars, informal event without proper classing, felt amazing (74 of the cars are faster than mine on paper).
In the wet is the only time I experience lift off oversteer.
Have you experienced that, as I think you're running an RSB on stiff setting right?

In the wet, yes. It's perfect for Autocross. Here's what I've found -- A good fast-rotating autocross car becomes scary at high speeds in the wet. This year I found myself in the gravel trap a few feet away from the wall after Turn 8 in Laguna Seca when I lifted off the accelerator and it snap oversteered. Educational and code-brown experience for sure -- so I noted that in your video, your car did the same. Do be careful if you track your autocross setup. Two suggestions: Reduce rear sway bar stiffness for wet track to the softer setting, and increase rear tire pressure in the wet to make sure you can cut through the water to have enough grip.

 

[WoodinvilleDan]

Dan, do you have a thread or something to describe the tuning process, with all the details and your long-term satisfaction with it? I have thought about it, but it's my family car and I need it to be reliable, and I need my better half to be happy with it too.

Hey, sorry I didn't see this reply (if you @WoodinvilleDan then it'll notify me, FYI)

I don't have a thread that I created about it but there are a couple already on the forum.
In short, it is totally safe. This is my daily driver and had similar concerns.
I've been tuned since mid 2018, and recently working on an extra high octane revision (for when I don't mind an extra $4/tank for some extra power), though I can easily flash back to the normal premium fuel tune, or stock tune if I need to (e.g. take to dealership for some reason).

Just email [email protected] and they will provide instructions, and on one of these threads I wrote a brief summary of the steps

 

[bdc101]

Thanks @WoodinvilleDan , I'm not a twitter user so I don't ever think to use the @ tag.

If you have a good thread, by all means point me in that direction. I may look into it. I'll do a good search later.

 

[Collin S]

I have a 2018 mazda 6 touring (2.5 non turbo). been wanting alittle more power. put in a new air filter and removed the cat convertor and replaced it with a resonator to reduce sound. any advice on maybe a possible tune or something? not really sure how to work with skyactiv engines

 

[TalonTsi90]

I have a 2018 mazda 6 touring (2.5 non turbo). been wanting alittle more power. put in a new air filter and removed the cat convertor and replaced it with a resonator to reduce sound. any advice on maybe a possible tune or something? not really sure how to work with skyactiv engines

Youve done literally ZERO research pal...

 

[Cdn17Sport6MT]

I think the meaning, here, is that removal of the main cat is of potentially limited usefulness (and does not exactly help the environment {my comment})... and that less restriction on the intake side has seen varying results, with different folks. Some swear by it, others not.

The Skyactiv-G 2.5 is pretty hard to add power/torque to... but can benefit from more octane (using a Tune).

 

[tickerguy]

Yeah there's nothing to be had by modifying either the intake or exhaust as neither is restrictive to any material degree and both are resonant tuned which, if you disrupt that, will likely cost you performance. That's by direct measurement so.... yeah.

 

[TechMaster6]

Yeah there's nothing to be had by modifying either the intake or exhaust as neither is restrictive to any material degree and both are resonant tuned which, if you disrupt that, will likely cost you performance. That's by direct measurement so.... yeah.

I disagree 😂

Unless you can show me dyno number 🧐

 

[TalonTsi90]

I disagree 😂

Unless you can show me dyno number 🧐

The exhaust i agree on, the intake, hell no.

 

[jevbro96]

Ok, this might sound like a fantasy that makes no sense, but my knowledge of how the skyactive engines work (maybe even engines overall) is a bit limited, so I thought I would ask the experts here the question.
So, tuning skyactive engines is considered 'stupid' and a waste of time, as they have a compression ratio of 12:1 factory.
Not considering the funding, would it somehow be possible to increase the cylinder size, thus in turn decreasing the compression ratio of the engine itself, to then again add power in the form of turbocharger or supercharger to possibly gain more horsepower than it would with the factory set up?
I'm new here, so please go easy on me 😅

So I stumbled upon this research..

"Calculating the dynamic compression ratio is actually pretty tough. To do it, you use the stroke length and the connecting rod length to determine the position of the piston when the valve is fully closed. Because this ratio is found when the piston is in the middle of its stroke, it's always lower than the static compression ratio. Like static compression, a higher compression ratio means more efficient fuel use and better fuel economy."

Anyway, my mZ6 ratio is 14.5:2 & produces 27psi of boost after a tune.

 

[TalonTsi90]

Anyway, my mZ6 ratio is 14.5:2 & produces 27psi of boost after a tune.

You cant have a ratio more than 1 and what produces 27psi? Your farts?

 

[WoodinvilleDan]

The Skyactiv-G 2.5 is pretty hard to add power/torque to... but can benefit from more octane (using a Tune).

When you said this it was true, but the world has changed in the last 13 months
People are starting to realize these engines are shockingly boost-able and can produce remarkable power while retaining great mpg.

At this point the transmission seems like the bigger limiting issue than the engine (in Corksport's turbo kit development and race car use, they've destroyed multiple clutches and entire transmissions), the automatic transmission is theoretically stronger than the manual in the case of our platform, but that is still an unknown, and technically Mazda claims the FW transmission was built for around 200ft/lbs, so if we're pushing 250 it seems fine, but if we get into the 280/300/320 range I'm not sure either transmission can take that without being modified....

Skyactiv Supercharger Quest

I am on a quest...To transform a great car into my dream car. to supercharge the Skyactiv 2.5L. I want the peak power of the 2.5T with the broad power band of the 2.5L. Goal: To be on par with e46 M3 or Civic Type R. (and way faster than the Skyactiv 2.5T: less torque, more horsepower). I...

www.mazda6club.com

 

[GWL]

When you said this it was true, but the world has changed in the last 13 months
People are starting to realize these engines are shockingly boost-able and can produce remarkable power while retaining great mpg.

At this point the transmission seems like the bigger limiting issue than the engine (in Corksport's turbo kit development and race car use, they've destroyed multiple clutches and entire transmissions), the automatic transmission is theoretically stronger than the manual in the case of our platform, but that is still an unknown, and technically Mazda claims the FW transmission was built for around 200ft/lbs, so if we're pushing 250 it seems fine, but if we get into the 280/300/320 range I'm not sure either transmission can take that without being modified....

Skyactiv Supercharger Quest

I am on a quest...To transform a great car into my dream car. to supercharge the Skyactiv 2.5L. I want the peak power of the 2.5T with the broad power band of the 2.5L. Goal: To be on par with e46 M3 or Civic Type R. (and way faster than the Skyactiv 2.5T: less torque, more horsepower). I...

www.mazda6club.com

If the transmission for the NA 2.5L is rated for up to 200 ft/lbs that's disappointing. I thought the 2.5L turbo and the NA had the same transmission, any idea where we could find this info?

 

[WoodinvilleDan]

If the transmission for the NA 2.5L is rated for up to 200 ft/lbs that's disappointing. I thought the 2.5L turbo and the NA had the same transmission, any idea where we could find this info?

according to my research and the comments of some Mazda technicians the NA transmission is 'FW', whereas the turbo transmission is 'GW' version. Overall they ARE the same transmission, but the GW has more splines and stuff to beef it up, so the FW is still a rather strong transmission just probably going to have issues over 300wTQ, but should be fine to 300wHP or close. I'll see if I can find links/sources of the differentiation of those transmissions.

The biggest concern for any of the transmissions is heat (auto or manual), as long as we keep the heat down we should be good. So far, running the supercharger with the oil cooler I've never seen transmission/coolant/oil temps above 222f, and checked my transmission fluid last weekend and it still smells fresh!
(before adding boost, definitely drop the transmission pan, replace filter).

Point is, I think unless we're trying to push really high power (over 300wHP), and we manage heat, then the transmission will be fine.

 

[1125ASL]

The carriage can always go faster than the horse, but you can only whip the horse so hard.

Get a different car if you want a performance car. Unless you wanna do an LS swap. lol A company in CO tunes Miatas with a 550 hp V8 shoehorned into a stock(ish) chassis.

I have to agree with the advice to "get a performance car." In the 90s I had the great privilege to participate in a BMW performance test drive event for 3-Series coupes and sedans on a tight auto-cross course setup, IIRC in an Oakland Coliseum parking lot. The event was informative and tremendous fun. Even more fun than driving a 3-series myself was sitting in the 1st row passenger seat while the host, a man who trained F1 pilots, took us around the course at speed. An Asian couple sat in the 2nd row, the female squealing in alternating bouts of delight and deathly terror. I looked back at them. Her male partner was pale and in shock.

I have no doubt that a mortal driving any dedicated race vehicle he could fit in, if his life depended on it, could not match that F1 pilot trainer's time. Impossible. I would not believe a street sedan could be so swift if I had not experienced it myself. The G-forces were brutal and extreme. (I have experience riding a 150hp superbike.)

I also predict that any mortal driver with skills well above the average commuter, while driving a bone-stock late 90s BMW 328i RWD (meeting OEM specs) would run circles around the Mazda 6 on the course shown in the video.

IMO it's more work and less fun going fast in a FWD vehicle vs. an already-finely tuned stock RWD vehicle.

I recently saw a video from inside the cabin of a current Corvette Z06 around a nice big racetrack, with top speeds likely 2.5-3x faster than what I experienced on the above tight auto-cross circuit. I don't think that Z06 driver had nearly the fun I did on the auto-cross circuit in a stock 90s BMW 3-series sedan.

 

[TalonTsi90]

while driving a bone-stock late 90s BMW 328i RWD (meeting OEM specs) would run circles around the Mazda 6 on the course shown in the video.

Youre on crack dude. I say that having driven a slew of 325i's in the early 90s, and as fun as they are, they are NOT remotely as fast as a stock, let alone S/C'd 6. Teaching F1 pilots has nothing to do with driving a car good or fast. Especially if youre talking the F1 prop "racer".
Also, i can pull 1.7 G's in my 3, if you wanna talk about being scared in a 4 door.

 

[Benedict]

Considering we're getting (US trim) 184hp out of 2.5 liters with 16v, balance shafts, variable valve timing, and all kinds of goodies, it seems obvious this engine has made a LOT of compromises for fuel economy, emissions, and other efficiencies.

Maximizing horsepower was not a high priority (though they did okay on torque).

All said and done, the Mazda6 is damn good at what it tries to do - within its price and quality class.

Too many people on this forum want this car to be something it isn't. It's not a performance car and efforts to make it one aren't going to be productive. For the money you'd spend, choose a higher performance, different car. Zoom-zoom!

Well put.