2018 1.4 seems to have a high baseline dyno

[Nataphen]

I just bought a 2018 hatch turbo last month. It’s all stock now except for cutting out the air box silencer from behind the wheel well liner. I did my baseline dyno today with ~6,800 miles on the car.

A baseline is just a starting number to show gains, I know, but it surprised me when it popped up. I was expecting 115-125whp maybe. The first run was 150whp/170wtq, but the sheet screwed up because it was set to complete at higher than the stock limiter. It lost about 5hp/tq with every run.

Researching a little bit, it looks like all the stock ones I’ve seen peak at 4800-5000RPM. Mine was ~5800 every time. The weather couldn’t have hurt, but those were the weather corrected numbers. Raw numbers were 155whp/175wtq on my first pull. Does anyone have any idea why the car may be making higher numbers, and at a higher RPM?


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[Nataphen]

Bumping this up a tad. Just wondering if anyone has any thoughts on this.


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[RMinNJ]

Chevy bumped up the hp and didnt tell anyone?

 

[Nataphen]

Right? You’d think they’d have mentioned that in the press release.

Uglier headlights, standard RS appearance on hatchbacks, available keyless access and heated seats on LT trim…oh, and by the way, 30 more hp and tq. :/


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[66roadie]

Take your car to 6 different dynos and I'd bet you'll get 6 different readings.

A dyno is only really accurate in comparing before & after upgrades, provided the same machine is operated by the same operator.

 

[Nataphen]

Take your car to 6 different dynos and I'd bet you'll get 6 different readings.



A dyno is only really accurate in comparing before & after upgrades, provided the same machine is operated by the same operator.

I’m aware, and that’s why I asked about the peak power RPM being at 5800 instead of 5000. I just use the baseline to measure gains, but it’s abnormally high, and the power seems to carry to a higher RPM than all the stock dynos I’ve seen. The car doesn’t fall on its face after 5000.

I use this dyno for all my cars, and it’s not a happy one. That said, I know there are variances, and the peak numbers themselves aren’t as big of a question to me as where the peak power is.


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[skurtov]

Can you get a reading at another dyno? Curious to see a rough average.

 

[JTee2017]

Check the engine code.

Did they happen to put the new 1.5L Cruze engine in it? lol

 

[Nataphen]

Can you get a reading at another dyno? Curious to see a rough average.

I may do that. It would satisfy my curiosity too.

I read all these reviews and posts about how the 1.4 feels anemic after 5000, and I always thought it felt like it pulled pretty well all the way to 6000. After seeing the dyno, that made sense, but it doesn’t make sense that it’s peaking at a higher RPM than all the others I’ve seen.


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[Nataphen]

Check the engine code.



Did they happen to put the new 1.5L Cruze engine in it? lol

That would’ve been really nice of them!


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[SnotRocketRS]

Is yours auto or manual? I have a 17 1.4 so mine theoretically should be the same depending on transmission.

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[Nataphen]

Manual.


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[Nataphen]

One thing about this dyno that may cause a different outcome is that it’s a mechanically linked AWD dyno. All four wheels are turning at the same speed, even on a 2WD drivetrain. I’ve always liked this because it keeps the wheel speed sensors happy, and the ECU thinks it’s driving down the road as opposed to wheels losing traction or being on a dyno.

Some cars like my Mustang actually had a “dyno mode” on the stock tune. The numbers would inflate compared to actual road output (to make the owners feel better I guess). Other cars like my Mazdaspeed 3 would go completely wackadoo sometimes and pull/surge power randomly. Using this dyno, it shows exactly the power that you get when you’re driving on the road. That may or may not show something different than the usual two wheel dynos on this car.

I’ve also never ran anything but top tier brand 93 octane in the entire time I’ve owned the car. The factory 138hp/148tq rating is technically for 87 octane. Maybe GM just allowed the knock sensor to add more timing than before. Just spitballing at this point.

I have a dyno setup for next Friday at a different shop. I don’t know anything about their shop or their dyno, but I guess we’ll see what happens there.


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[skurtov]

One thing about this dyno that may cause a different outcome is that it’s a mechanically linked AWD dyno. All four wheels are turning at the same speed, even on a 2WD drivetrain. I’ve always liked this because it keeps the wheel speed sensors happy, and the ECU thinks it’s driving down the road as opposed to wheels losing traction or being on a dyno.

Some cars like my Mustang actually had a “dyno mode” on the stock tune. The numbers would inflate compared to actual road output (to make the owners feel better I guess). Other cars like my Mazdaspeed 3 would go completely wackadoo sometimes and pull/surge power randomly. Using this dyno, it shows exactly the power that you get when you’re driving on the road. That may or may not show something different than the usual two wheel dynos on this car.

I’ve also never ran anything but top tier brand 93 octane in the entire time I’ve owned the car. The factory 138hp/148tq rating is technically for 87 octane. Maybe GM just allowed the knock sensor to add more timing than before. Just spitballing at this point.

I have a dyno setup for next Friday at a different shop. I don’t know anything about their shop or their dyno, but I guess we’ll see what happens there.


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The knock sensors do retard timing with the higher octane gasoline, and you will gain a little more HP. But the amount you're recording? Definitely not. I could see maybe around 5-7hp gained at most

 

[Nataphen]

The knock sensors do retard timing with the higher octane gasoline, and you will gain a little more HP. But the amount you're recording? Definitely not. I could see maybe around 5-7hp gained at most

That’s what I figured. Definitely something weird going on. I hope the next dyno sheds some light on this.


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[Nataphen]

Stoking the fire. I called the shop where I’ve already dynoed to give them my email today, and I asked for some other stock car numbers. This week, they did a stock baseline on a 2018 911 GT3 (500bhp). It made 450whp on their dyno, so that’s about right. I’m not any less confused by their answer.

I still have the other dyno set for next Friday. I’ll let y’all know.


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[skurtov]

Stoking the fire. I called the shop where I’ve already dynoed to give them my email today, and I asked for some other stock car numbers. This week, they did a stock baseline on a 2018 911 GT3 (500bhp). It made 450whp on their dyno, so that’s about right. I’m not any less confused by their answer.

I still have the other dyno set for next Friday. I’ll let y’all know.


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Keep us in the loop. Maybe chevy did something clever with the engine they didn't readily release to the public.

 

[Nataphen]

Is there a trick to making these cars act right on a two wheel dyno?

Traction and stabilitrack off, and it’s still going nuts.


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[Nataphen]

Got it sorted out. They had to run it in third gear to keep the TCS happy for some reason. They couldn’t find a clean tach signal, and I didn’t know where to tell them to hook up, so no RPM or torque unfortunately. I know fourth is preferable, but I ran fourth at the last place on the first run, then third on the next two. Fourth made more power than third, so this is a conservative test if anything.

Signs seem to point to this car making more than 138bhp on 93 octane. I don’t know, but here you guys go:

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[JTee2017]

Got it sorted out. They had to run it in third gear to keep the TCS happy for some reason. They couldn’t find a clean tach signal, and I didn’t know where to tell them to hook up, so no RPM or torque unfortunately. I know fourth is preferable, but I ran fourth at the last place on the first run, then third on the next two. Fourth made more power than third, so this is a conservative test if anything.

Signs seem to point to this car making more than 138bhp on 93 octane. I don’t know, but here you guys go:

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Interesting. Maybe hook up a GOOD OBD II scanner and check what timing advance/retard is while driving and logging the live stream using the 93 octane.

Then. . . fill up with 87 and do the same. If using regular pulls back timing then that might be key. Should tell you if the ECM/PCM maybe has two tables to run off? I know the 3.6L LFX engine from 2014 to maybe present did. Though I never saw any performance data.