Veloster N – Occam's Racer

Veloster N Engine Modes Dyno Tested

The Veloster N has three power levels and three exhaust sound settings, which you can customize to your liking. There is also an economy mode that limits boost pressure and should provide better fuel milage. But how much do these modes differ in power output?

The N Custom mode shows the engine and exhaust sound have three settings each.

I wanted to know, so I went to Overdrive Automotive in Johnson City and had them dyno my car. (Side note, if you are in Central or Southern NY, I would highly recommend Overdrive for tuning your Megasquirt or whatever, they know Miatas really well.)

The rollers are at ground level, so the car is lifted up for dyno testing.

I didn’t test all the modes, figuring it was most important to get the data for the lowest and highest power settings.

Eco: This mode is supposed to limit boost pressure to 6-7 psi and return better fuel milage. I believe this is a separate setting than the lowest engine mode available in N Custom mode, so I selected this mode from the preset modes on the steering wheel button.
Normal: This is the lowest setting in N Custom mode, and probably the same as choosing Normal mode from the presets. This is the mode I use for all street driving (or when I’m on track and forget to turn on N Custom).
Sport: I didn’t test the tune in between Normal and Sport+. I didn’t test the middle exhaust setting either.
Sport+: This is the highest engine setting, which I initially set with the quietest exhaust, because I don’t like pops and bangs or loud pipes.
Sport+ with exhaust: Same as above, but with the exhaust in the loudest setting. This mode has the burble tune and exhaust valve open, and should show the highest power output.

Note that this test was done on a DynoJet, and so all readings are corrected for elevation and temperature. The engine is bone stock and has about 4000 miles on it (it was replaced once under warranty).

Shockingly, the dyno recorded virtually identical power output in each mode. Even in the green Economy mode, which is supposed to limit boost pressure, the dyno read 244 hp and 251 ft-lbs.

Notice there’s a dip in the chart at one point, the dyno operator said this was likely the ECU pulling timing for a second to deal with heat. The engine was in Eco mode on this pull, but you can see that just a second later the engine picked back up again and posted identical numbers to the other modes.

244 hp is about a 12% drivetrain loss, which is better than I expected. But note that the car was going into winter storage, so I filled the tank with ethanol-free 90 octane, and it may make more power on 93, and even more when the engine loosens up.

What do the engine modes do?

Given that all modes made the same amount of power, the next question is, do the engine modes do anything at all? Knowledgeable people in the N world have stated that the different tunes change the engine’s responsiveness and boost targets in the mid-range, rather than max power. Other sources suggested that the engine modes are only different at partial throttle.

Maybe that’s true, but what about Eco mode? From every account I’ve read, nobody is actually getting better fuel mileage in Eco mode. One source claimed Eco mode only works in the UK. Or that Eco mode is different on different platforms, and limits Velosters to 12-13 psi, but Elantras are limited to 6-7 psi. Well one thing is for certain on my car, either there is no low-boost mode, or all modes are low boost.

Next let’s talk about the tunable exhaust. It did add loudness, but without adding power, I don’t see the point. I like to hear my tires working, it helps me drive at the limit. And so louder pipes just limit my driving.

Finally, there’s the pops and bangs of the burble tune. Internet pundits claim this is to keep the turbo spinning, so that there’s less turbo lag between shifts. I can’t confirm or deny this, as dyno pulls are done in one gear, and so lag (or the lack of lag) doesn’t show up on the dyno. I have a manual transmission, and so I could see this being useful if I missed a shift, but for someone with a 8-speed DCT, I’d question the usefulness of the Rice Krispies soundtrack.

Next year I’ll test the different modes on track and see if I can determine any difference in the data. It may be difficult to ascertain that through the noise of driver error, but we shall see what the Aim Solo data logger says.

At this point, all I can say for sure is that there’s no difference in power or torque in any engine mode or exhaust setting.

How Experience Level Affects Lap Times

I recently had an opportunity to put three drivers of different experience levels in my Veloster N, and have them drive the same track on the same day. I logged the data on my Aim Solo, and by interpreting that in Race Studio we can see exactly how each driver went about their business.

The track is Pineview Run’s short course, and on the driving line, this is just shy of a mile long. Most race tracks are going to be double the size, so keep that in mind when I talk about time deltas.

The car is my Veloster N, completely stock except for the base model’s roof extension, rather than the Veloster N’s spoiler. I removed the spoiler for scanning purposes, and it wouldn’t change any of the results here. Because it was late in the season, I’d put the my track tires in the basement, and so the car was on Linglong Crosswind all-season tires. I don’t believe this affected anything in the test, but it would be interesting to see the results on a proper track tire. Maybe next year.

The drivers

Let’s meet the drivers:

Green – Dan is a novice driver who has done a couple HPDE weekends, as well as a couple Track Night in America events. He’s recently been signed off for solo driving, and after looking at his data and watching him drive, I can confirm he was ready to graduate. His threshold braking is pretty good, and he has acceptable inputs and awareness. Dan also has a Veloster N, and so it was easy for him to get in my car and go quickly. The track, however, is all new to him, and so it took him a few sessions to throw in a hot lap. In the data, Dan has the green lines because, well, he’s green.
Red – Jack is an advanced level driver who races in Champcar. He’s an aggressive driver, and so I’m giving him the red colored lines in the data, to signify the red mist. Well, it’s not really red mist, it’s just a driving style that’s reminiscent of a couple other teammates, Ben and Danny. All three of them break traction early in the corner, and then make multiple fast steering corrections to optimize grip, trajectory, and acceleration out of the corner. This style looks aggressive (and exhausting) on video, because it requires many quick inputs, but it’s actually a very calculated and effective way to go fast. Jack has also never been to this track before, and he’s also never driven a FWD car on track, either.
Blue – I’m the blue lines on the speed trace, because blue signifies cool. Not because I’m a cool cat, but because I drive with a cool head and have a smooth and economical driving style. I admit that the aggressive drivers I’ve mentioned (Ben, Danny, and Jack) are all a bit faster than I am over the course of one lap, but during an endurance race stint, my style is much less abusive on the car, tires, and driver. Because of that, I get into less trouble than anyone I know (3 black flags in 11 years/26 races, and only one was my fault; pat-pat). My big advantage versus the other two drivers here is that I know the track well, because I literally wrote the book on it.

So now we know who the drivers are, we can ask these questions:

How much does driving experience affect lap times? If we compare the Green and Red drivers, we’ll see that the advanced driver goes three seconds faster than the novice. This is mainly down to three factors, which I’ll explore below.
How much does track familiarity affect lap times? For this we’ll compare the Red and Blue drivers, and see that track knowledge (and car familiarity) makes a difference of 1.35 seconds.

Novice vs advanced

The first thing we’ll take a look at is how a novice (green) and advanced (red) driver approach a track that’s completely new to them. I’ve put three callouts on speed trace.

Novice drivers are taught to brake in a straight line, and so the speed trace shows straight lines on deceleration. As drivers progress in skill, they learn to release the brakes while they turn in. This is called trailbraking, and results in a speed trace that has a “hockey stick” shape. You can see this at point A. Trailbraking picks up a small amount of time in the braking zone, but more importantly, it allows the car to be pointed down track earlier, so the driver can get on the gas earlier.
Another trait of advanced drivers is that they “back up the corner.” This means that braking and turning are done earlier, which allows them to get on the gas earlier. On the speed trace, I’ve drawn green and red vertical arrows that show the point where the driver has committed to full throttle. In most corners, you’ll notice that the advanced driver is to the left of the novice driver (backed up). The best example of this is at the 2200′ mark, where the advanced driver is at full throttle 100′ earlier than the novice driver; that’s over 7 car lengths earlier! The result of this is that the advanced driver gains 6/10ths of a second before the next braking zone.
Another telltale sign of an advanced driver is a higher minimum speed, or vMin. I’ve drawn two horizontal arrows here, and in this spot the advanced driver is going 5.5 mph faster than the novice driver, at the slowest point in the corner. If you think about it, this is really an 11 mph difference, because the novice driver slows down 5.5 mph more, and then has to accelerate 5.5 mph more just to get back to where the advanced driver started. Novice students are taught to throw away corner speed for the sake of safety (“in slow, out fast”), but advanced drivers know to keep their minimum speed as high as possible.

Finally, it’s worth noting that the advanced driver not only had never driven a FWD car on track, but he only drove one 15-minute session. On the other hand, the novice driver owns the same car and did four sessions. This shows just how much skill and experience level matter. But before we move on, let me point out this novice driver is better than most novices, given the amount of track time he has. Put a first-time track driver in the car, and my novice is going to put six seconds between them, easily.

Advanced knowledge vs advanced

Next let’s take a look at how two advanced drivers go at it. As mentioned earlier, Jack (red) is probably a little faster than I am, but I have car knowledge (my car), and track knowledge (my country club).

There isn’t really that much difference between us. I have a slight advantage going into Turn 2, and hold that while we trade corners back and forth. Going into and out of the Turn 11 (2500′-3000′) is where I gain all my time. With a couple more sessions to figure out that corner, Jack would be a couple tenths off me. Take a look:

Youth and skill (red) vs old age and treachery (blue)

I’ve put a color-coded circle around each corner indicating which driver had the higher vMin. I have five to Jack’s four, but two of my corners are considerably higher.
Jack brakes too early, too deep, and gets on the gas 50′ later than I do. He loses about a second going into and out of The Knuckle. There’s more difference between us in this one corner than the rest of the track combined.

It’s really just that one corner that makes a difference, and it reminds me of another person who is faster than me everywhere but Pineview: my identical twin, Ian. You might know him from You Suck at Racing (blog | book). One reason he’s the fastest on the team is he’s always the fastest through the corner that matters the most. What we’re seeing here is the exact opposite, which is that if you blow an important corner, you blew the lap.

There is one other wrinkle here, which is that Jack was in the passenger seat on my run, but he did his runs without a passenger. Jack is about my size and build (5’11”, 180cm), and I would have gone a bit faster without 180 lbs of ballast. But I’m just grasping at straws here, and with more track time, Jack would eventually surpass me.

Conclusions

In the end, there’s a difference of over four seconds between the three of us, and this on a track that’s only a mile long. On most tracks, it’s safe to say the delta might be 8-9 seconds. Of all the mods you can do to your car, driver mod is the most important mod. And as you can see from the data, you bring that with you, to unfamiliar cars, and to tracks you’ve never driven.

Veloster N Driving Modes on Track

The Veloster N has five driving modes: Economy, Normal, Sport, N, and N Custom. Er… I think I have this right, I don’t know, because I only use two.

Eco – Economy mode limits boost pressure, but from what I’ve read online, it’s not any more economical. So I don’t use this.
Normal – I use Normal mode on the street.
Sport – I’ve never tried this, I don’t see the point.
N – I don’t use this, the suspension is too hard, and the pops and bangs of a burble tune annoy this shit out of me.
N Custom – I use this mode on track. I have the eLSD and steering on full, but pretty much everything else is turned off or on the lowest setting. No rev matching, soft suspension, no stability control, and the exhaust as quiet as it’ll go. For some unknown reason, I’ve also had the engine in the lowest setting all year, which should be a nice surprise when I select full power next year (actually, I later found out there’s no difference in peak output).

I’ve driven my VN on track in both wet and dry conditions, and on good and bad tires. Now that I’ve had a chance to look at some comparative track data, I can answer some questions, such as:

Which driving mode is fastest on a wet track?
Which driving mode is fastest on a dry track?
How do all-season tires compare to a proper track tire?

Dry track: Normal vs N Custom

Since I only use the Normal and N Custom modes, I wanted to see how they compared on a dry track. My N Custom mode was 1.9 seconds faster. Woof.

Subjectively, the Normal mode sucks ass on the track. It takes the fun out of driving. The stability control is probably the main culprit, and switching to the N mode (on the fly) resulted in instant smiles from me and a “whoa” from my passenger. The way the car behaves is night and day different in N Custom mode. It’s astonishing.

This immediately changed the way I drove, from trying to maintain a higher vMin, to backing up the corner. I don’t mean to throw jargon at you, so let’s take a look at the data and I’ll explain those terms. I’ve highlighted the the three most significant differences with letters.

Red is Normal mode, Blue is N Custom (nannies off).

This is Turn 2, a right hand turn onto a short straight. You can see that the Red line has about 2 mph higher minimum speed (vMin), but when I get on the gas, the nannies nerf the acceleration and I only get .31 Gs of acceleration. The Blue line has .5 Gs of acceleration, which results in about a .4 second gain. This is entirely down to the car’s intelligent systems getting in the way of my driving.
This is T9, another right hander, this one cresting a hill. By turning off the nannies I can rotate the car, which allows me to get on the gas 95 feet earlier than in Normal mode. We call this “backing up the corner,” and it means that I’ve done my braking and turning earlier in the corner. This allows me to get to full throttle earlier, and gains half a second.
Notice here how the Blue lines are to the left of the Red lines, again this is backing up the corner, and doing that in the final turn is worth almost three quarters of a second as I cross the finish line.

What’s really interesting about this graphic is that I had no idea I was in Normal mode at first. I was driving with a passenger, chatting, and totally forgot to switch modes. Then suddenly I realized I hadn’t changed the driving mode. The Veloster N allows you to do this on the fly, and so part way through the lap I switched modes.

This allowed me to drive the car in a completely different manner. I could immediately feel the difference in the way the car behaved, and was able to extract a higher level of performance, and go 1.9 seconds faster. But I wasn’t aware of how differently I was driving the car until I looked at the data just now.

Wet track: Normal vs N Custom

I also got to try both modes on a cold, wet day. This was the same track with a slightly different configuration to avoid one of the big puddles. It was raining the entire time, and there was a lot of standing water on the track.

In N Custom mode, I spun the wheels a lot on acceleration, and had to short shift to third in a number of places. My best lap was a 1:28.838. In Normal mode, I managed a 1:28.592, but was still getting some wheel spin cresting a hill. So then I left it in third gear and did a 1:26.994. That’s a difference of 1.84 seconds, which is almost exactly the same difference the two modes had in the dry.

So that’s the ticket to going fast in a torrential downpour, put it in Normal mode and drive a gear taller.

The data below isn’t super exciting, the thing to notice is mostly the difference in vMin (or minimum corner speed). I’ve drawn little black arrows to show what I mean. When the nannies are on, I can maintain a higher speed in the middle of the corner, and this results in a faster speed down the next straight. The acceleration curves are about the same in N Custom and Normal, which I find a little surprising, and so I suspect that it’s the stability control more than the traction control that’s helping in the rain.

Red is N Custom, Blue is Normal mode (nannies on).

All-season vs track tires

I have three sets of wheels and tires: 235/40R18 Kumho V730 on Konig Countergram 18×8.5 +43 (42.3 lbs); Pirelli PZ4 235/40R18 on Motegi MR140 18×8.5 +45, (42.0 lbs) and Linglong Crosswind 235/35R19 all-season tires on 19×8 +55 OEM wheels (55.3 lbs).

The only reason I bought the Crosswind tires was because the OEM tires were worn out, and I was looking for the cheapest possible tire I could mount in the winter, while my summer tires are hibernating in a heated basement. I found the Crosswind tires on sale for $65 at Walmart, and expected absolutely nothing from them.

Just the same, I wanted to see what they would do on track, and I’ve been pleasantly supersized. They don’t suck. Because there’s not a lot of grip, they break away gradually, and slides are easy to control. Once sideways, the tires howl like a banshee, which helps you know how much you’re working the tires. Or overworking.

I’m leaning on these $65 tires so hard, they look like they want to come off the bead!

I haven’t tested the Crosswinds back to back with the V730, but I put down a 1:19.1 on the all-seasons, which is about 2 seconds slower than the Kumhos did on a previous occasion. This is surprising, because you’d expect the 200TW to be a lot faster than 400TW. For example, my 1.6 Miata is about 6 seconds faster on RS4s than it is on all-season tires. This all fits in with previous data I hand that shows that FWD cars lose less performance in low-grip situations (such as rain, dirt, snow, or shitty tires).

Red is Crosswing, Blue is V730. Not the same day, and my wife was in the car on the V730, but only a 1.9 second difference.

All said, I’m having Miata-levels of fun on these $65 tires. Had I known this was possible, I wouldn’t have three sets of wheels. With a better all-season tire, like a Michelin Pilot Sport A/S 4, I think you could do everything from daily commuting to track days on one set of wheels. I know a lot of people feel they need track tires for track driving, I’m just not one of them.