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Solar, OVT,

If I wanted to say "Give me the same final tune characteristics you gave Solar, but optimized for 89 octane.", could you do that? And does that reduce the number of back and forths interactions required to complete my tune?

The reality is that Solar has more experience and has already thought through this far better than I could. So I'd love to take advantage of what he ends up with for my own tune. The only difference is that I'd rather optimize for regular grade gas than premium, since the performance tradeoff is marginal, and the cost difference between regular and premium unleaded gas isn't.
I would almost pay extra for the tune options at each octane (we have 87, 89, & 93 typically here) so you can pick and choose based on your financial situation (I know here there are times when 87 is a ton cheaper than 89 and 93 but others times it is not and why not take advantage when you can?). How much extra did you say you would do this for? Also, would it involve data logging with each octane gas? Or are you able to convert without logging each octane.
 

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I'm primarily interested in the tuning characteristics you specified, because it sounds exactly like what I'd want. Tuning for regular octane is my secondary consideration, assuming the performance penalty is minimal. If the penalty is significant, I'd lean to optimizing for 93 octane like you did.

I'm not sure why starting with a tuned profile wouldn't reduce the number of required iterations, but I'll take your word for it.
 

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Discussion Starter #63
I'm primarily interested in the tuning characteristics you specified, because it sounds exactly like what I'd want. Tuning for regular octane is my secondary consideration, assuming the performance penalty is minimal. If the penalty is significant, I'd lean to optimizing for 93 octane like you did.

I'm not sure why starting with a tuned profile wouldn't reduce the number of required iterations, but I'll take your word for it.
OVT approaches every tune with the same progression of tuning changes, to ensure that he is diali in your car as built properly.

It's fine to have the same tune objectives as me but you didn't start with the same car as me so your final tune parameters will be different from mine by some amount.
 

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Discussion Starter #64
Regarding exhaust gas recirculaion valve function I decided to turn mine way down with the tune for two reasons.

The first reason is Mazda bragged about getting intake timing dialed in to get the right amount of heat on the outside face of the valves to prevent carbon build up from the egr recirculaion. I didn't have too much faith in that to begin with, but now that OVT has adjusted all the timing for efficiency and power that burn off affect could be diminished. So to prevent excess carbon build up I decided to have the egr turned way down. The only reason I ask OVT to leave it on a little bit is to make sure it doesn't seize up and not work when I need it to work when I flash back to stock for emissions testing.

Secondly the egr function has a secondary affect of reducing effective compression and effective engine displacement for improved fuel efficiency, sort of a pseudo Atkinson cycle as a result of the inert charge going into the combustion chamber. But that egr mixture is hot and dirty creating knoxk potential, so not really a good way to create the Atkinson cycle. Since OVT can dial in the intake valve timing to replicate the diminished egr function with clean cool air is a more fuel efficient way to do business.

I dont feel much guilt emissions wise, because returning a small percentage of exhaust gases back through the engine is only going to have a small percentage affect on emissions. My Mazda 6 without EGR is still probably way better for emissions than buying a full size emissions legal pickup.
 

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Discussion Starter #66 (Edited)
I was enjoying my tune's ability to zoom zoom this morning running up to 65mph in a 55 zone up a hill when a semi going 35 mph decided to pull into my left lane before signalling when I was only two car lengths back from his trailer.

It helped I was going up a hill so I was able to shed 30mph in about 1.5 car length with ABS doing it's thing, but if I was on the flat or downhill I'm not sure I would have kept from hitting him.

So this is a real world example of more power getting me "in more trouble" requiring heavier braking.

It makes me appreciate my car only weighing 3000 lbs as fueled. Still, when I do get around to replacing brake pads I will definitely go with a "stickier on the first bite" type of performance pad and high temp brake fluid. Going with a big brake kit is overkill unless you are road racing, but to each their own.
 

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Okay...now I'm really leaning closer/committing on joining in earlier. I'm just too preoccupied right now at my DHS work and preparing for my overseas trip..its just that I have to be back full time (end of March/early April, to focus/start the OVT tune support, commencing at that time period..)

I'm also leaning more on a max tune, under the common 87oct. Granted, I don't really have much complaints on the "out-of-the-box" stock 2.5L powerband (as I'm satisfied, based on my slightly aaggressive daily early work commute..). I just need some better oomph (when needed), over stock. Though of course I would welcome a more hp tune to my stock engine. Between HP and torque, I'm more interested really in optimizing the most often used in real world driving situations, the low end grunt..torque.
 

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Alright I'll try to get all questions answered:

Solar, OVT,

If I wanted to say "Give me the same final tune characteristics you gave Solar, but optimized for 89 octane.", could you do that? And does that reduce the number of back and forths interactions required to complete my tune?

The reality is that Solar has more experience and has already thought through this far better than I could. So I'd love to take advantage of what he ends up with for my own tune. The only difference is that I'd rather optimize for regular grade gas than premium, since the performance tradeoff is marginal, and the cost difference between regular and premium unleaded gas isn't.
Yes I can write you a tune similar to Solars with 89 octane. that wouldn't be a problem, there are a few slight variances that would be different, as your mods are probably not the same, and the MAF calibration would be a little different.
The main reason it takes more than 1-2 files is getting the MAF calibration, Timing adjustments, and igntion / fuel comp maps is, it takes time, the ecu re-learns after each flash, re-trims and adusts, then I go in and "clean up" those trims. it would take about 4-6 files for 87/89 octane. 91-93 takes more because there is more ignition timing increments to do.

I would almost pay extra for the tune options at each octane (we have 87, 89, & 93 typically here) so you can pick and choose based on your financial situation (I know here there are times when 87 is a ton cheaper than 89 and 93 but others times it is not and why not take advantage when you can?). How much extra did you say you would do this for? Also, would it involve data logging with each octane gas? Or are you able to convert without logging each octane.
I charge an additional $25.00 per extra map request. 87 and 89 would be very similar, maybe 1 file more / logging iteration for 89. 93 would take 2-3 more logging iterations compared to 87/89. for a total of 6-7 for 93, and 4-6 for 87-89.
(the logging / file amount is general, some cars need a finer touch at times and it may be a little more).

I'm primarily interested in the tuning characteristics you specified, because it sounds exactly like what I'd want. Tuning for regular octane is my secondary consideration, assuming the performance penalty is minimal. If the penalty is significant, I'd lean to optimizing for 93 octane like you did.

I'm not sure why starting with a tuned profile wouldn't reduce the number of required iterations, but I'll take your word for it.
The reason is, is because every car needs it's own individual, unique MAF calibration. No 2 cars flow *exactly* the same, and the MAF calibrations cannot be transferred between ECUs.

By the way, can anyone recommend a better book than this one to understand engine tuning?

Engine Management: Advanced Tuning: Greg Banish: 9781932494426: Amazon.com: Books


As with most things, I'd like to make an effort to get more educated about the things I don't understand well.
Greg Banish / Calibrated Success is a great place to begin. It can get quite in depth though, and the DVD's aren't cheap.
 

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My goals are roughly:

1. Be set up for 87 Octane, stock intake and exhaust. I doubt I will ever put an aftermarket intake on the car. I might put an aftermarket cat-back on at some point.

2. Broaden the torque curve; that appears to be the base expectation and outcome with these tunes to start with, which means I'm likely to smile right up front.

3. If possible remain in the high-mpg operating regime up another 500 RPM under light throttle conditions. This is a problem at present with the MTX cars as they have a taller final drive than the ATX; the ECU appears to come out of Atkinson-hybrid cycle around 2,500 RPM and that's right around 65mph. This means that driving at 70-75, which is quite legal in most of the US, costs you 5+ mpg! If that can be addressed.... great! If not, well, I'm living with it now.

4. [Classified] :)

I might be interested in also paying the additional $25 for a file set up for 92/93 rather than 87. Not sure on that yet; around here 92 is uneconomic; it's not uncommon at all for it to be 30% more than 87, which basically means it's a "only when you really want it ALL" fuel; those who buy 92-recommended vehicles really get it up the chute in this area.
 

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Discussion Starter #70
My goals are roughly:

1. Be set up for 87 Octane, stock intake and exhaust. I doubt I will ever put an aftermarket intake on the car. I might put an aftermarket cat-back on at some point.

2. Broaden the torque curve; that appears to be the base expectation and outcome with these tunes to start with, which means I'm likely to smile right up front.

3. If possible remain in the high-mpg operating regime up another 500 RPM under light throttle conditions. This is a problem at present with the MTX cars as they have a taller final drive than the ATX; the ECU appears to come out of Atkinson-hybrid cycle around 2,500 RPM and that's right around 65mph. This means that driving at 70-75, which is quite legal in most of the US, costs you 5+ mpg! If that can be addressed.... great! If not, well, I'm living with it now.

4. [Classified] :)

I might be interested in also paying the additional $25 for a file set up for 92/93 rather than 87. Not sure on that yet; around here 92 is uneconomic; it's not uncommon at all for it to be 30% more than 87, which basically means it's a "only when you really want it ALL" fuel; those who buy 92-recommended vehicles really get it up the chute in this area.
#3 was on my hit list verbatim, and I think it has been taken care of. I have thought of a decent way and place to perform a check. Hopefully I can do it this weekend.

#4 Spill it! LoL

Lastly there must not be enough high octane european cars in your neck of the woods. In So Cal, not once has it been more than a 10 cent extra over 89 for premium because gas stations are always half full of european cars so usage is high enough for it to keep up with the price swings and economies of scale of the lower grades. It is what it is.

Personally, I think for a lot of people a tune on 89 probably makes the most sense. It's the "just right" mama bear approach, where you still get most of the benefits of the tune and higher octane for just an extra 10 cents per gallon.

It just comes down to how much are you willing to pay for max throttle response and how obsessed are you with getting every ounce of power out of the engine?

I'm addicted to the throttle response of 91, and love getting the most out of what I've done and I don't buy enough gas to care about the cost, so I won't be going back to lower grades.
 

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#3 was on my hit list verbatim, and I think it has been taken care of. I have thought of a decent way and place to perform a check. Hopefully I can do it this weekend.

#4 Spill it! LoL

Lastly there must not be enough high octane european cars in your neck of the woods. In So Cal, not once has it been more than a 10 cent extra over 89 for premium because gas stations are always half full of european cars so usage is high enough for it to keep up with the price swings and economies of scale of the lower grades. It is what it is.j

Personally, I think for a lot of people a tune on 89 probably makes the most sense. It's the "just right" mama bear approach, where you still get most of the benefits of the tune and higher octane for just an extra 10 cents per gallon.

It just comes down to how much are you willing to pay for max throttle response and how obsessed are you with getting every ounce of power out of the engine?

I'm addicted to the throttle response of 91, and love getting the most out of what I've done and I don't buy enough gas to care about the cost, so I won't be going back to lower grades.
Completely agree with the crappy mpg when cruising anywhere above 65. Highways here are typically 70mph too. This would be a great issue to improve. @solar365 I believe baby bear had the "just right" items?? Hahaha. I am coming from a TSX that insisted on 93 octane, I did like the thought of 87 octane price cut but I am let down too often with WOT (especially 2nd gear) to care at this point. I'd rather the price of 93 octane and continue to enjoy the cheaper monthly loan payments :)

And agree @tickerguy , spill it! Hahaha. It's been wide open up to now! All us ignorant ones like myself need to learn from the knowledgeable ones like you guys!
 

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I think the question is how much you give up having it set up for 87 .vs. 89 .vs. 93. If most of the gains can be had on 87 IMHO being set up for that gives you the most flexibility, and the ECU already does take fair advantage when you run the higher octane fuel.

Remember that 87 actually has slightly higher effective energy evolution capability, IF you can burn it without detonating. The reason is that as it burns faster the engine is slightly more efficient when using it.

In addition keep in mind that stock setups pay particular attention to emissions. This is why EGR is used; it reduces peak combustion temperatures (bad for efficiency!) but also reduces NOx.
 

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Discussion Starter #73
I think the question is how much you give up having it set up for 87 .vs. 89 .vs. 93. If most of the gains can be had on 87 IMHO being set up for that gives you the most flexibility, and the ECU already does take fair advantage when you run the higher octane fuel.

Remember that 87 actually has slightly higher effective energy evolution capability, IF you can burn it without detonating. The reason is that as it burns faster the engine is slightly more efficient when using it.

In addition keep in mind that stock setups pay particular attention to emissions. This is why EGR is used; it reduces peak combustion temperatures (bad for efficiency!) but also reduces NOx.
All I can say is the valve timing changes by themselves added very little power. It was when the spark timing advance was made in the second tune that 80% of the power increase came. Since then it has primarily been clean up of maf calibration and other minor stuff that hasn't made much of a noticeable difference in max power. Perhaps ovt can elaborate on how much of the timing advance is made possible as a result of the octane vs, removing high load/wot conservatism (even on 91 this wasn't taking advantage spark timing advance by stock tune) or running more rich.

With EGR is NOx reduced for the entire mixture or just what is recirculated?
 

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All I can say is the valve timing changes by themselves added very little power. It was when the spark timing advance was made in the second tune that 80% of the power increase came.
That's expected. Timing advance helps (a lot) right up until it hurts (badly!); over-advanced timing breaks things (like connecting rods!)

The trick to this is that ignition isn't an instant event; for maximum power and efficiency you want the mixture to ignite as the piston just passes TDC. As RPM goes up you thus want spark to occur earlier before TDC in degrees, since in time ignition delay is more-or-less constant (that is, the crank turns more degrees in a unit of time at higher RPM than lower, obviously.) This is why the old mechanical distributors had centrifugal advance mechanisms in them.
With EGR is NOx reduced for the entire mixture or just what is recirculated?
The entire mixture. The point of EGR (and retarded timing to some extent as well) is to lower peak combustion temperatures.

There's a dance going on in modern vehicle engines in this regard; running lean improves efficiency as does maximizing charge expansion (that is, timing ignition to occur just as the piston passes TDC) but results in higher peak combustion temperatures; that, plus the presence of excess oxygen, results in NOx formation. In diesels, which inherently run very lean except at full power output, this has forced NOx-reducing catalysts using urea injection into the market in order to meet emission standards (which are god-awful expensive and complex systems, leading to long-term maintenance concerns.) This is likely to wind up eventually happening with gas-powered vehicles as well -- especially if HCCI engines, which Mazda and a few others are experimenting with, come to fruition.
 

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That's expected. Timing advance helps (a lot) right up until it hurts (badly!); over-advanced timing breaks things (like connecting rods!)

The trick to this is that ignition isn't an instant event; for maximum power and efficiency you want the mixture to ignite as the piston just passes TDC. As RPM goes up you thus want spark to occur earlier before TDC in degrees, since in time ignition delay is more-or-less constant (that is, the crank turns more degrees in a unit of time at higher RPM than lower, obviously.) This is why the old mechanical distributors had centrifugal advance mechanisms in them.

The entire mixture. The point of EGR (and retarded timing to some extent as well) is to lower peak combustion temperatures.

There's a dance going on in modern vehicle engines in this regard; running lean improves efficiency as does maximizing charge expansion (that is, timing ignition to occur just as the piston passes TDC) but results in higher peak combustion temperatures; that, plus the presence of excess oxygen, results in NOx formation. In diesels, which inherently run very lean except at full power output, this has forced NOx-reducing catalysts using urea injection into the market in order to meet emission standards (which are god-awful expensive and complex systems, leading to long-term maintenance concerns.) This is likely to wind up eventually happening with gas-powered vehicles as well -- especially if HCCI engines, which Mazda and a few others are experimenting with, come to fruition.


Cam timing won't break a con-rod. (ignition may). Cam timing or phasing is the actual degree of the cam (360 rotation) physically being adjusted to a certain degree advancement ahead of the crank degree (RPM).

The cam timing is use to help fill the cylinders with air, (and exhaust cam timing to help excavate it out). But getting more air alone on stock maps doesn't really bring much more power, as the stock maps ignition timing is so low the actual burn event is happening way late in the cycle ATDC. There is a "sweet spot" so to say, for most engines, around 16* ATDC give or take a couple degrees.

Adjusting Air fuel and timing helps create more peak cylinder pressure aka more power. That, along with the cam timing (which can control dynamic compression) all in tandem makes the most cyl pressure which = the most power.

even on 87 or 89 octane you should notice a clear difference in response, but on 93, which allows enough timing to get that burn in the "sweet spot" range gives it that peak response, I guess you could say.
The only issue with 87 octane specifically is it keeps the tune KNOCK LIMITED, which hinders total performance because getting that "sweet spot" isn't possible because of knock. But you can get close, at least closer than stock maps.

Hopefully that makes sense. I do want everyone to understand that on 87 you will get a different response, but I don't want you guys coming out the gate expecting it to be like adding a 50 shot of nitrous or something lol.

regarding MPG, increasing it is not a problem on any octane. I tested some "dedicated" MPG maps on the sky 2.0L and got nearly 50MPG
 

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Ovt, can you tailor a tune that would optimize more on increased torque? I'm more focused really on improving the low end (the most often used in everyday driving; but of course more hp is welcome..). If so, I'll be buying two maps (87 & 91)..and consider me counted in the list, for sure.
 

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Ovt, can you tailor a tune that would optimize more on increased torque? I'm more focused really on improving the low end (the most often used in everyday driving; but of course more hp is welcome..). If so, I'll be buying two maps (87 & 91)..and consider me counted in the list, for sure.
absolutely. If you want all the focus on lower end, not a problem. If you want peak torque early in the RPM cycle that's not a issue at all. on both 87 and 91 or if you want 87 your low end torquey tune and your 91 more of a broader power range no problem. I've done so many different combos of tunes with these skyactivs practically anything is possible lol
 

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Just for clarification, if the tune is for 93 and 91/92 is used for fill-up couple times, will it cause any issues... In NorthEast, not all gas stations have 93 octane, they sell Premium as 91/92 octane also.

Thanks in advance.
 

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This is true here as well; most "premium" is actually 91 or 92.

If I could buy 93 at a 10% increase over 87, I would. However, it is quite common here to find that premium is 20% or more expensive over 87. There was a period of time a couple of months ago when gas prices were very low where it was more than 30% more! Needless to say that's flat-out ridiculous.

The same was true for diesel at that point in time, which is even more-ridiculous.
 
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