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Yeah, without a turbo you need to get it breathing before you get grunt of the engine. On my MTX the usual from cruise is to shift down 2.
 

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Driveability was IMHO the biggest gain; the torque lift in the 2000-3000 RPM range was quite significant. More so than the horsepower gain at the top.

Nonetheless if you're expecting low-RPM grunt from a 4-banger without a scroll on it you're going to be disappointed.
 

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It's an iterative process -- you get a file, you log it, you upload the log to them, they send you another one. Takes 3-4 passes to dial it in.
 

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Thanks for the response guys, I seems to be an isolated incident. I drive the car to work again on Friday and played with the acceleration, gave some hard acceleration, parcel acceleration mashed it and felt the "click" I was go in to ask about that but you guys have answered it already. Car feels alot better. When I reset the fuel monitor does that reset the driving habit memory as well?
I know this car is not a corvette by any means but when I said lag it literally like I was towing a house.

That sucks we cannot get the hand held for our 6.
 

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Thanks for the response guys, I seems to be an isolated incident. I drive the car to work again on Friday and played with the acceleration, gave some hard acceleration, parcel acceleration mashed it and felt the "click" I was go in to ask about that but you guys have answered it already. Car feels alot better. When I reset the fuel monitor does that reset the driving habit memory as well?
I know this car is not a corvette by any means but when I said lag it literally like I was towing a house.

That sucks we cannot get the hand held for our 6.
Resetting the average MPG/MPH gauge will not affect anything. If the car looses battery power, Ie. dead battery, or unhooking the battery for about 5 minutes, then yes it completely resets.

Now that I think back there has been times were I mash the gas and the transmission doesn't respond promptly like it usually does, especially with AC on, on a hot day. I feel like as long as cars are so computer controlled these days cars will run into "confused' moments like this. So to make sure when need emergency/evasive engine response just be sure to hit the kickdown for definite downshift.
 

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Hello, what is the recommended rev limit cutout?

Right now I can't hit 60mph in my 2014 touring 6 with manual trans before it cuts out at 6200 rpm.

I don't want to set the rev limit with the tune too high where there is no appreciable gain(pull), but do want to improve the 0 to 60 time.

I will be using the 91 tune when the handhelds come out for my Mitsubishi ECU'd car.

Thanks.
 

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How aggressive do you wish to be?

IMHO trying for the last 100 RPM is a fool's errand. These are not drag cars and 0-60 time is a drag thing, not real. In real traffic you have to shift if you're merging or continuing to accelerate anyway (e.g. to 70mph to enter a freeway lane) so the gap means little.

For best acceleration sans the shift time you want to shift when the NEW gear is in the power band (e.g. near peak torque) for most cars. The advantage of moving the rev limiter up a bit is not really in the use of the last 100 or 200 RPM, it's in the fact that the ECU starts to cut fueling back a hundred or two RPM *before* the limit is hit. Therefore it's not to get the other 200 RPM, it's to be in the "fully fueled" part of the curve to the point where you shift so you hit the sweet spot in the torque curve with the new gear.

If you're shifting at 6,000 then you're pretty much in the game. That last 200 RPM (if you look at the data logs) is running into reduced fueling in anticipation of the cutoff. If you raise the limiter by 200 RPM then if you run beyond 6200 you're STILL going to hit it and probably won't do much of anything for real-world times. Yes, you're standing 0-60 will improve a bit because you avoid a shift but in real-world driving the gain is close to nil or may actually be negative. You want the NEW gear to land the tach right in the 4,000-4,200 RPM area when you shift for maximum acceleration. The wide 1-2 gearing difference (1.9x!) makes this impossible to achieve, but if you shift 1-2 @ 6200 RPM you should land right ~3,200 RPM, which is near peak torque and thus not disastrous.

2-3 is a 1.49x gearing difference; shift @ 6000 and you land right on 4k, which is close to optimum. You can go ahead and take the other 200 RPM (shift @6200 if you wish) but I bet you don't see any material difference in time if you run 3rd out doing so.

Basically the ratio of the 1-2 shift in the box handicaps you and there's not much you can realistically do about it. This is also responsible for some of the complaints people have with drivability on the 1-2 shift. The AT is quite a bit better in that regard in that the 1-2 ratio is a 1.75x and the 2-3 is a 1.39x, but it also has a shorter final ratio but that doesn't alter the relationship between gears, of course.

I would have liked to see FIXED 1.5 ratios for the first 4 gears in the MT; it would have made a hell of a difference. That would have been 3.7, 2.47 (instead of 1.947), 1.64 (instead of 1.3!), 1.09 (instead of 1.02; note we're basically flat now) and then flatten it out a bit -- maybe 1.3 for the last two "overdrive" gears (0.839 .vs. 0.837 and 0.645 .vs. 0.68)

That would drop 6th's RPM by ~5.4%, which would be JUST enough to get right up against 80mph on flat land WITHOUT the engine dropping out of Atkinson. The result would be a lift of fuel economy @ 75mph by about 2-3 mpg on flat land and MUCH improved low-end acceleration in the 1-2 shift, which would help a lot around town.
 

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So ticker are you saying that having OVT increase the red line to, say, 7K won't really do much in terms of overall power and driveability? I tend to like the sound of smooth rev-happy engines.

Sent from my SM-P580 using Tapatalk
 

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I don't think anyone knows where the margins are with regard to maximum safe revs, but I'm quite sure whoever finds out is going to dislike the cost of doing so very much. It's your wallet if you crank it up by that sort of margin and then actually use it.
 

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Ive had the revs increased to around 6.7k (might be 6.8, would have to double check) on my 2.5 mazda 3. Its useful in avoiding the limiter. Stock redline feels a bit premature in that the engine is still winding happily at 6.2. At any rate, after an initial test near 6700rpm, if im ever feeling like dogging the car out i still mostly respect the stock redline, but just dont have to worry about limiter cutting in just before a shift.
 

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I don't think anyone knows where the margins are with regard to maximum safe revs, but I'm quite sure whoever finds out is going to dislike the cost of doing so very much. It's your wallet if you crank it up by that sort of margin and then actually use it.
By way of a reply: it seems to me that the Skyactiv engines are built somewhat delicately....yes forged steel rods and crank and forged alloy pistons and full counterweighting on the crank - but section sizes are all very slender... Caution warranted re the revs. Oh, also long, long stroke...'Lotsa rod reversal forces. Narrower than previous design big-end bearings... 'Danger, Will Robinson!' (betraying my age here, lol...)
 

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Be careful with this; the SkyActiv engines use EGR as part of their detonation control; the point of EGR is to reduce peak combustion temperatures (and thus control NOx) and disabling it will definitely throw a MIL, prevent you from passing emissions testing if you live in such an area and with this engine it might have a severe impact on performance as the ECU may need to aggressively pull timing as well.
 

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Be careful with this; the SkyActiv engines use EGR as part of their detonation control; the point of EGR is to reduce peak combustion temperatures (and thus control NOx) and disabling it will definitely throw a MIL, prevent you from passing emissions testing if you live in such an area and with this engine it might have a severe impact on performance as the ECU may need to aggressively pull timing as well.
I got a replay from OV about this topic

" the car has a "psuedo" EGR. no actual valve. We modify this in the tune " 0:)

My mitigation now to use Low-SASP oil with low Calcium to reduce carbon build up and avoid LSPI ( low speed pre-ignition ) with lower Calcuim.

I recommend every one to move to this direction, and I know 2 oils that have such characteristic :

Mobil 1 ESP 5w30
Mobil 1 X1 5w30
 

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This is a great thread if a bit long (yes I just finished all 132 pages) Thank you to all the initial starters and test people for this tuning thread and thanks to OVT for actually figuring out how to tune the sky-active engines. I really wish I had been interested in tuning back when I bought the car 100K miles ago but now is always the best time to start something. As soon as I check which ECU is in my March 2013 built car contacting OVT is a go.
 

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I just installed a K&N intake in my '17. The car isn't rejecting the mod (it's enjoying it from what I can tell), but it's a little 'wonky' under acceleration in 4th/5th gears. Could a tune help with this?
 

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I don't think I can read 132 pages lol but to each its own I guess, this car was never meant to be fast, we knew it, with all the money you spend on tune, engine mods, equipment, etc it'd be in the thousands and could've bought a faster car from the start

$560 + the other things you need to have is simply just too much for something that may be 20hp max, in real life, id be a lot less
 

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Update from OVTUNE...

Me: Have you made any progress with the 3rd gen 2.5 mazda 6 handheld units? Denso and mitsu?

OVTUNE : Not yet sorry. We can't figure out why it won't work as the ECU is identical

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