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Discussion Starter #221
just logged the car today. Was flooring it around after I logged the files and the mass airflow said: 178.6g/s !

2014 atx auto with injen cai
Part of me wants to say that is awesome, the other part of me says yikes that is a lot of variability car to car mods or no mods if you can really hit that number consistently.

Was it like 20 degrees out making the air super dense? That would help explain some of it but still that sounds like an outlier.
 

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Hey everyone, sorry for anyone still waiting I got a little sick yesterday and couldn't get much done. Feeling a little better today so i'm gonna knock out everyone's updates and base files
 

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Part of me wants to say that is awesome, the other part of me says yikes that is a lot of variability car to car mods or no mods if you can really hit that number consistently.

Was it like 20 degrees out making the air super dense? That would help explain some of it but still that sounds like an outlier.
You have to GRAPH these numbers from the logger and look at the various bits of data available; one-offs (e.g. "max" in the logger's window) are not particularly instructive. In fact they can be downright misleading.

If you don't have Excel Google's free spreadsheet thingie (cloud-based) will eat csv files, of course, and produce charts from them.

When you look at the MAF/Timing graph I posted the other day you'll see all sorts of spikes; they're not particularly instructive. What is quite interesting is that the ECU is pulling timing quite early in the run, slowly gets to where it doesn't have to any more and then right near the top output is limited by knock once again.

You can't use more air if you're forced to retard timing by knock. This data strongly suggests that the car is not airflow-limited (that is, I'd get little or nothing in terms of performance out of an intake, exhaust or both running 87.) This is supported by the MAP sensor reading at WOT which is showing figures indistinguishable from 1 bar; intake restriction (assuming the exhaust is not restricted) shows up at higher RPM as a depressed absolute MAP -- that is notably absent in the data.

Note that the worst-case depression over 1.0 ATA is 6% and it's not steady-state. Steady state looks closer to 2-3% and an unknown amount of that is coming from the intake runners and cylinder head (e.g. ports, etc.) I'll bet most of it is, but that's verifiable and I intend to do it.

Proof will come after the next set of logs I send in, as these results also strongly suggest that there's another half degree (roughly) of timing advance available in the midrange (and corresponding output improvement) with the current file IF I had a more knock-resistant fuel in the car, and maybe quite a bit more (in other words on 92 there might be another couple of degrees of ignition advance possible; all you know if there's no pullback is that there is probably more possible, but you don't know how much more.) What should happen if neither intake or exhaust is restricting output is that the knock retard should go away, output should go up somewhat and so should mass airflow while MAP depression should not increase at the same rate. If it does (or increases more) then that would indicate intake restriction.

I intend to test that hypothesis relatively soon; I suspect the next turn of the calibration will be close to "best and final" on 87 with my stock config, and the next thing I will attempt after that is a set of data logs against that but running 92 octane.
 

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Part of me wants to say that is awesome, the other part of me says yikes that is a lot of variability car to car mods or no mods if you can really hit that number consistently.

Was it like 20 degrees out making the air super dense? That would help explain some of it but still that sounds like an outlier.
To be fair it was -12c ooutside and i hit 178 twice just from visually looking at logger while going wot
i consistently hit 168-170g/s
 

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Got my base file in, so cali has some 90+ degree days coming so im going to datalog on those days to simulate a typical summer day.
 

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Discussion Starter #226
To be fair it was -12c ooutside and i hit 178 twice just from visually looking at logger while going wot
i consistently hit 168-170g/s
That's freaking cold compared to us Florida and So Cal dataloggers who have been logging in 70F plus temps. That would account for most of the difference.

Your spark advance stock will also be through the roof at those temps as well. dang near as good as a tune in 90F degree weather if you check the ignition advance temp correction table.
 

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Discussion Starter #227
Y

You can't use more air if you're forced to retard timing by knock. This data strongly suggests that the car is not airflow-limited (that is, I'd get little or nothing in terms of performance out of an intake, exhaust or both running 87.) This is supported by the MAP sensor reading at WOT which is showing figures indistinguishable from 1 bar; intake restriction (assuming the exhaust is not restricted) shows up at higher RPM as a depressed absolute MAP -- that is notably absent in the data.

I intend to test that hypothesis relatively soon; I suspect the next turn of the calibration will be close to "best and final" on 87 with my stock config, and the next thing I will attempt after that is a set of data logs against that but running 92 octane.
Yeah, knock is more a function of torque than hp per mazda engineers so it makes sense the knock is occurring lower in the powerband. I'm not a physics expert, but it could be due to the fact that it takes time for the air to heat up as it is being compressed (ie. it takes time for the molecules rubbing on each other harder as a result of the higher pressure to create heat), so the slower compression of the air charge allows more time for the air to heat.

Also, agreed on the exhaust. If you remember I ran into serious knock just swapping to a high flow velocity exhaust, which bumped the airflow at low rpms resulting in more torque and more heat thus resulting in more knock. It wasn't that I was ruining up the exhaust evacuation. The same limitation would be in effect for the intake, which does add flow capability across the entire rpm range.

So taking the knock limitations of the engine along with the ignition timing temp correction tables, I'm not looking like such a fool now in my quest to lower intake temps. I'll be wrapping the intake tract in nomex in the near future and increasing airflow through the radiator before summer arrives to do what I can to drop coolant temps which also affect the timing table.

Despite the limited benefit of intake and exhaust (maybe ~7% improvements combined on stock tune and some unknown amount with the tune), don't forget the changes to engine responsiveness and tractability have their own merit that the tune cannot replicate.

Same for the higher octane as well. It adds a certain "strength" quality to the engine that anybody that has ever driven a premium only engine can attest to. The tune can't replicate that either.

Not to say a tune can't provide some kinds of improvements in engine response, but it isn't the same thing. This is a tough thing to put into words, but it's very real by seat of the pants feel.
 

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I haven't messed with the software too much, but does the obd scanner part show things like coolant temp and iat temp? or do you have to log to get that data?
 

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I haven't messed with the software too much, but does the obd scanner part show things like coolant temp and iat temp? or do you have to log to get that data?
Torque can obtain IAT and coolant temp (along with a lot of other data) off a standard OBD adapter; those PIDs are standardized and known.

OBD is also about checking trouble codes; if you want real-time data you're logging whether it goes to a file or simply is displayed.
 

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6800 rev limit makes a nice difference. With the base tune it doesnt make a whole lot more power but its smoother and feels a little better adjusted to 91 octane than stock.
 

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Discussion Starter #232
For kicks today I tried driving at reasonable acceleration rates (keep in mind I'm in California where almost everybody accelerates fast) while up-shifting at 2000rpm, and it can do it in 2nd 3rd and 4th. 1st is too short, so I needed to shift at 2500rpm to be at a reasonable rpm in 2nd, and 5th and 6th are too tall that the engine bogs a little trying to pull at such low rpms.

This is something to keep in mind for those pondering what kind of fuel economy possibilities there are with the tune. It isn't just steady state hwy driving that can be improved.

If you change your driving style to take advantage of the extra torque from the tune by shifting earlier, the lower rpms are likely to make significant improvements in city driving mpgs.
 

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Just curious at what tune are you starting to see real tq improvements? im only on base tune but around town driving has improved a bit.
 

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Discussion Starter #235
Torque improvements came somewhat incrementally. Tunes 1, 2, 3 and 5 for me all provided regular driving torque improvements in different ways. 1 was by valve timing, 2 and 3 were by ignition timing mostly I think, and 5 was by lucky accident through fuel delivery timing. Like tickerguy is saying, most of the improvement comes from the ignition timing changes.
 

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Ok, thanks. Im waiting for the weather to warm up to socal regular temps later this week and will log then. Luckily for me I work in an industrial complex where there are empty streets so a nice WOT 1st through top of 3rd will be easy to log.
 

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Ok, thanks. Im waiting for the weather to warm up to socal regular temps later this week and will log then. Luckily for me I work in an industrial complex where there are empty streets so a nice WOT 1st through top of 3rd will be easy to log.
You don't want to do that.

Log WOT in ONE gear from ~1500 RPM to redline. 3rd is better, but 2nd is acceptable. 3rd, however, has the problem of likely drawing the attention of the po-po since it will run up to around 80-85mph; 2nd tops out right near 60 and begins at ~15-20mph.

You do NOT want to shift during the run; that will screw up the data.
 

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Discussion Starter #238
Ok, thanks. Im waiting for the weather to warm up to socal regular temps later this week and will log then. Luckily for me I work in an industrial complex where there are empty streets so a nice WOT 1st through top of 3rd will be easy to log.
There is no compelling reason to run to redline in 3rd. It will only take one car driving on the supposedly emtpy streets to have a very very bad day. Odds are low but the stakes are high. Don't put anybody else at risk.
 

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I'd love to have a nice closed airport runway for this sort of thing, or a track (e.g. dragstrip) but I have neither, so I make my runs in 2nd.
 
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