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Discussion Starter · #1 ·
I will be getting a automatic forte on the dyno to repeat these results here in the next week or two. What you are looking at is our Manual Trans Forte.

I will address the biggest elephant in the room up front:

Why that big spike and power drop off around 3600-4100 RPM?

- We believe this a loading/dyno related behavior. Our load curves on the street are much smoother than this and the datalogs don't show curves like this.
- When the dyno operator stabs the throttle in 4th gear, the large incurred load spikes boost pressure and all the correlations along with it are working to get it under control. This is what you are seeing.
- On the street, I hope you all DON'T load the car up at 4th gear at 3000 rpm and stab the throttle. You should downshift to a lower gear and that is how we are doing our tuning for street driving and throttle take-off.

So, ignoring the spiked area, you will see we have significant power/torque increase across the entire rev range.

The stock tune horsepower curve is a little wonky, and you can see that is smoothed out for a nice gradual power increase to redline.
The stock tune torque curve is a little better but we still managed to smooth it out a little better while making more across the board.

Parameters and their adjustments:

Boost - boost target increased 1psi to about 16. We managed to hold 16ish until 5700 rpm until it starts to taper to about 12 at redline. All of the stock hardware inhibiting flow is part of the boost taper. You can see this in the dyno graph when power levels off.

Air/Fuel Ratio - For this particular stage, we are pretty happy with leaning out the VERY rich factory Air/Fuel settings to a very modest ~.76 Lambda (~11.1:1 AFR). We could probably make more power here but deciding to stop here for this stage.

Timing - We are very modest here as well. We spent the most time on the timing maps, as this is where we listened and logged for knock the most. We only ended up with about .75 to 1.5 deg increase in most cells, and a little over 2 deg in the remainder of the tune. We believe there is more power here and will continue that experiment when the intake and intercooler get installed for Stage 1.

In the midst of these basic changes we raised some limiters that inhibited making power. There are a few tables that need to be adjusted.



With all that being said our next steps are:

- Continue monitoring our test customers. We have great feedback on drivability and butt dyno increases but those claims will be validated on the dyno.
- Stage 1 is next, to include adjustments for intake breathing mods (intake, throttle body, intercooler).
- finish our downpipe so we can do what we will dictate as Stage 2 (tune to accompany stock turbo with exhaust mods)

I hope to have all this wrapped up in the next couple weeks, and really done just after this big KDM meet we have to be at on 8/13. Preparation for that is hindering some development of several items.

Thanks for the support!
 

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I like it. Much steeper curve.

Could you elaborate more on the power drop down the line, though?
EDIT:
Sorry, I am taking it back. I misread the graph.


I do not want to open Pandora's box, but why can't you floor at low RPM? I mean, I hear all the opinions on load, LSPI, and such. However, just for the moment, if it was a big problem, wouldn't the manufacturer prohibit it from happening in the first place? I mean, if the low end torque was so dangerous, wouldn't KIA/Hyundai, or any other car maker, stop doing it? Yet, they advertise the high torque can be reached as low as 1750 RPM.

Just a thought...
 

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Discussion Starter · #3 ·
The reason is gearing.

When using a dyno to measure power, you need to be in the gear that's as close to a 1:1 ratio as you can get. For our manuals, its 4th gear.
Going lower than 3K in 4th gear is pointless on the street, you'd simply never have to do that. Downshift to accelerate faster.
Flooring the car under 2000 rpm is fine in first and ok in second. Probably wouldn't do that in 3rd gear.

I could have started the pulls at 2000 rpm but the first part of the curve would probably be an even worse spike because of the load. Starting the pull later wouldn't have changed anything either.

You can make a lot of torque in 1st, 2nd, 3rd just like the car maker's tell you, but if you run a dyno test in those gears, the numbers aren't "true." The torque/power is multiplied due to the gear ratios.
 

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Discussion Starter · #4 ·
So I just checked how Mustang Dyno's (the type we are using now) measure power and it turns out it doesn't matter what gear for that load cell type dyno.

With that being said, we'd now either use 3rd or 4th gear because they take longer to power thru vs 1st or 2nd giving us more accurate power measurements.
 

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Don't you need to put gearing information and wheels size into the dyno to get the measured power adjusted (calculated)?

Regarding my question, it was more rather about driving the car in any gear on a street. Again, I was trying to justify how much gas can you give say in 5th gear or even in 6th. Half throttle (about 15% max boost), 3/4, more? Why do we say to not use the low end torque since it is the reason they (Hyundai) built this engine (added turbo)? And this is the advantage we have over NA engines.

Now, for the dyno. I always thought it would be more beneficial to start the dyno pull from say 20 MPH in 4th gear to get the compressor enough time to create boost in lower end as it was designed (again, Hyundai says max torque starting at 1750 rpm - why not check it there?).
 

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Discussion Starter · #6 ·
Don't you need to put gearing information and wheels size into the dyno to get the measured power adjusted (calculated)?

Regarding my question, it was more rather about driving the car in any gear on a street. Again, I was trying to justify how much gas can you give say in 5th gear or even in 6th. Half throttle (about 15% max boost), 3/4, more? Why do we say to not use the low end torque since it is the reason they (Hyundai) built this engine (added turbo)? And this is the advantage we have over NA engines.

Now, for the dyno. I always thought it would be more beneficial to start the dyno pull from say 20 MPH in 4th gear to get the compressor enough time to create boost in lower end as it was designed (again, Hyundai says max torque starting at 1750 rpm - why not check it there?).
You have to remember they use an engine dyno that they can rev to whatever and whenever they want, because the engine isn't trying to spin a transmission and 2 wheels and some axles.
You place A LOT of extra stress on an engine when you try to go high throttle at low RPM in a higher gear than you need to. It's bad, don't do it.

They are advertising that low RPM max torque number for the purposes of accelerating from a stop or very low speed. If you are rolling in first gear and stab the throttle, you're going to get up pretty quickly and the engine probably makes all of it's torque by the advertised RPM.
 

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You have to remember they use an engine dyno that they can rev to whatever and whenever they want, because the engine isn't trying to spin a transmission and 2 wheels and some axles.
You place A LOT of extra stress on an engine when you try to go high throttle at low RPM in a higher gear than you need to. It's bad, don't do it.

They are advertising that low RPM max torque number for the purposes of accelerating from a stop or very low speed. If you are rolling in first gear and stab the throttle, you're going to get up pretty quickly and the engine probably makes all of it's torque by the advertised RPM.
Yes, I know that. One thing is their test, another is true life.

But

You place A LOT of extra stress on an engine when you try to go high throttle at low RPM in a higher gear than you need to. It's bad, don't do it.
It's bad, don't do it.
As it may seem stupid question, why is it bad? Again, if it was so bad for the engine, with nowadays computers torque/power/timing would be limited to not allow to do bad things to your engine.
I get the concept of vibration, low oil pressure, and such. Yet again, I am trying to justify WHY would someone make an engine that can kill itself. Even automatic can keep low RPM and pretty high torque in ECO mode.
Therefore, what is the problem here?

Oil pressure? At idle I get about 10-15 PSI. At 1000 RPM it is above 30 PSI. At 1500 RPM - I do not recall, I will check, but higher of course. Hence, oil not a problem here...
Tranny? Shift indicator does not tell me to downshift. Sure, I can make it to suggest a downshift, but only if below 1750 RPM and at WOT in any gear higher than 3rd.


I simply do not see reason why would one create and engine, give 100k miles warranty on it, and make it such way that it may destroy itself.
We learnt we can't really increase boost, we can't really change much to get more power without proper tune. So it tells me - Hyundai/KIA must have thought about anything then.
 

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Discussion Starter · #8 ·
Yes, I know that. One thing is their test, another is true life.

But





As it may seem stupid question, why is it bad? Again, if it was so bad for the engine, with nowadays computers torque/power/timing would be limited to not allow to do bad things to your engine.
I get the concept of vibration, low oil pressure, and such. Yet again, I am trying to justify WHY would someone make an engine that can kill itself. Even automatic can keep low RPM and pretty high torque in ECO mode.
Therefore, what is the problem here?

Oil pressure? At idle I get about 10-15 PSI. At 1000 RPM it is above 30 PSI. At 1500 RPM - I do not recall, I will check, but higher of course. Hence, oil not a problem here...
Tranny? Shift indicator does not tell me to downshift. Sure, I can make it to suggest a downshift, but only if below 1750 RPM and at WOT in any gear higher than 3rd.


I simply do not see reason why would one create and engine, give 100k miles warranty on it, and make it such way that it may destroy itself.
We learnt we can't really increase boost, we can't really change much to get more power without proper tune. So it tells me - Hyundai/KIA must have thought about anything then.
I can sit my foot on the floor in neutral and bounce the engine off redline for as long as I want and kill the motor myself really quickly. Why does the automaker let me do that?
Your automatic in ECO mode example is just an example of gearing. It can be in low RPM and make decent power to accelerate because it's not in 4th gear or higher.

Oil pressure and the transmission can be effected, but I'm talking about stress on the rotating assembly. If you have an automatic and you let the computer do the shifting, it will select the appropriate gear based on vehicle speed/rpm/throttle input based on the ECU programming.

If you have a manual transmission, I can select 6th gear @ 2000 rpm @ ~40 ish MPH and try to floor it. You know what's going to happen?
The car will barely accelerate and vibrate like crazy because the engine cannot move the car at that speed and gear. Engine load will be very high for no reason. That's extra stress on the engine and doesn't need to happen.
The computer is going to see the insane boost and load spike and kill timing and add fuel to keep the engine from exploding.

The car really wouldn't start accelerating until 4000-4500 rpm because that's where it makes peak torque if we managed to keep our foot to the floor in that gear the whole time.

Anyone who's driven any manual transmission car and accidentally shifted into 5th gear instead of 3rd at light throttle (or skipping any gear in general without enough speed) would know what I'm talking about.
 

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If you have a manual transmission, I can select 6th gear @ 2000 rpm @ ~40 ish MPH and try to floor it. You know what's going to happen?
It will go smooth.
Mine is stick. I was testdriving Tucson and in ECO it would keep low RPM and upshift quickly. Much heavier car, yet goes quickly.

The car really wouldn't start accelerating until 4000-4500 rpm because that's where it makes peak torque if we managed to keep our foot to the floor in that gear the whole time.

Anyone who's driven any manual transmission car and accidentally shifted into 5th gear instead of 3rd at light throttle (or skipping any gear in general without enough speed) would know what I'm talking about.
I think we are talking about two different cars. Mine goes smooth at 2000 RPM no matter what gear. At half throttle in 6th at 2000 RPM and I get nice and smooth acceleration. No really need to drop gear.
And I would rather say it dies above 5000 RPM (one can feel torque drop - and the tune graph proves it :) ). Sure, it lurches above 3000 RPM, yet 2k provides smooth acceleration.
 

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Grats Sxth, keep it up!

Speaking of high load. What is considered high?

In 6th gear going 60 mph basically resting my foot on the pedal shows 30% load. A little push sends it to 50%.

Would that be considered to high load for 6th gear ?

All the times traffic goes from 65-70 down to 55-60 and then right back to 65-70... 60% of the time I don't downshift but I'll gently hit the gas and slowly speed up, but Torque says I'm at 50-60% load doing that.
 

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Speaking of high load. What is considered high?

In 6th gear going 60 mph basically resting my foot on the pedal shows 30% load. A little push sends it to 50%.
Exactly.
We keep saying, including me, that low engine speed and high load are not good. But where is the line?

Just to stir it up even more. Diesel. All TDIs have huge torque at 1500 RPM or lower. Plus diesels do not like high speeds. Yet, they last long...
 

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Discussion Starter · #14 ·
If you are too low of speed and RPM in a higher gear and go to a high enough throttle, the drivetrain will lug and start vibrating. That's when it's too high.

Please start a new thread if you want to discuss driving habits with low rpms in high gears.
 

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I'm curious how tuners get more power from tunes. Is it progressive like overclocking a CPU/GPU where you raise the settings incrementally until instability is detected? A local tuner here called EuroCharge is charging $699 CND for the tune, without a spare ECU. And ...

DYNO: Although the tune was developed on our Dyno, the price of the tune does NOT include a dyno test of your vehicle. Dyno charge is $150.00 for 3-4 pulls w/print-out result. To do before/after comparison testing, the dyno charge will increase accordingly (call for details and appointment booking)

No mention of further tuning on these Dyno runs, either. They're claiming +45wHP / +70wTQ improvements.

Hyundai Veloster Turbo 1.6L Tune hyundai veloster - Eurocharged Canada


For that much, I was hoping for a bit more power. I guess they're projecting those numbers based on stocked parts?
 

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What is Eurocharge? Seems to me like a crap. Euro model (say KIA Cee'd GT that is more or less equivalent of Forte) has same engine, 1.6T and puts out 204 HP and 265 Nm (100 Nm is about 74 lb*ft, hence it is 195 lb*ft). Same parameters as US version.

Do not call me an expert on this, but getting +70 ft*lb is a lot. That is going from 190 to 260. That is almost 40% increase. It is a lot. IMO tune itself would not do that. You must have some other modifications.
Even VW 2.0 GTi does not have these numbers out from factory (stock). And this is 2.0 not 1.6.


As for comparison of clocking CPU to tune - no, it is not really that.
I have far more experience with computers than tuning ECUs, but it is not as simple as increasing voltage or rather dropping voltage, but increasing base frequency to keep system stable. There is much more to it.
You can get more power by changing timing (advance it in some places under certain conditions), changing air-fuel ratio, allowing for more boost, and dozens of other parameters.

And then, as you can imagine, changing say air intake, spark plugs, or exhaust, allows for more tweaking, just like changing RAM (to a different frequency) that opens up more power.
 
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I don't know what to think. I got the reference from VT.org but their numbers are contradictory. They are advertising +45WHP but at the same time says stock 201hp tune 251hp.

So which is it? whp or bhp?

I rather go buy a bridge in Alaska.
 

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I don't know what to think. I got the reference from VT.org but their numbers are contradictory. They are advertising +45WHP but at the same time says stock 201hp tune 251hp.

So which is it? whp or bhp?

I rather go buy a bridge in Alaska.
dyno shows WHP, specs give CHP or BHP or HP (there is a small difference between BHP and HP, as - OF COURSE - BHP is imperial, while HP is metric).

So, if your specs get say 200 BHP, it means it has 203 HP, and it may have anywhere between 170-190 WHP.
WHP drops due to transmission, alternator, and such.


BHP - British Horse Power, or Boiler, or Brake, or Imperial... many names are there... but the best is Imperial.
HP - just Horse Power, metric.
WHP - inconclusive, it is power measured at the wheels and can be presented as WBHP or WHP depending where you are and what dyno is being used. However, it brings so big error margin that calling it WHP or WBHP makes no difference. It is rather for comparison from run to run (mod to mod/tune to tune).


I think when they say stock 201 to 215 is simply based on assumption of the same power loss (either by simply value or percentage) and while you gain 45 at the wheel, it may translate into 50 at the crank.

I hope that helps.
 

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Just my 2 cents. There is no number for the load/RPM thing. Many factors determine that point such as the 2 mentioned, plus air temp, egts, valve timing, ignition timing, vehicle weight, tire size, gear ratios, drag, drive train resistance etc etc etc. So no there is no magic formula.

And diesels last longer cause of all the detergents in the oils. Most also run a bypass filter instead of these first run POS filters.

One last note, a 60mm tb really helped raise that 5k upper limit

And 6th told me on Facebook that the new 60mm tb will be ready this coming month

Sent from my Pixel using Tapatalk
 

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Grats Sxth, keep it up!

Speaking of high load. What is considered high?

In 6th gear going 60 mph basically resting my foot on the pedal shows 30% load. A little push sends it to 50%.

Would that be considered to high load for 6th gear ?

All the times traffic goes from 65-70 down to 55-60 and then right back to 65-70... 60% of the time I don't downshift but I'll gently hit the gas and slowly speed up, but Torque says I'm at 50-60% load doing that.
What exactly are you referring to when you say load? You mean throttle input?

I've been noticing a lot of the so called turbo surge lately. I swear, I never experienced this but recently got to 50,000KM mark on the odometer. Before that it was very linear but now it's like I'm learning stick for the first time and that jerk you get from the 1st gear release.

Why would a car not have this behaviour trait but all of a sudden they do? I'm hoping after the breather mods it'll work itself out. I'm also hoping the tune SXTH comes out soon.
 
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