Initial thoughts/review of my new Sonic (longish)

[K-Bob]

My initial thoughts/review of my new car.
Gleaned from notes taken during first 900 miles of driving.

2017 Sonic LT sedan
1.4 Turbo, 6 spd manual
stock 195/65-15 on alloys
cold tire pressure set to 37ft, 35 rear
base suspension

So glad I got the 2017. I love the new front end and new taillights. The car looks great. I got it in the exact color combo I wanted, and the convenience package too, with the nice steering wheel and enhanced Information Center. I really dig the manual controls for recirculate and A/C. Of all the cars out there in this price range, this is the most perfect one for me. The only other car I was considering was the Yaris iA, which is a great car with perfect size and weight and excellent handling, although it is a little slow. But I was able to get a sweet deal on the Sonic which is in the next class of car above the Yaris iA.

Great ride, but a little soft. Competent handling. The rear feels like it wants to come around.
But it's so tall and soft and tippy though. Feels like I'm bouncing and rocking all around. And there is like zero steering feedback: no road feel, no buildup of effort as Gs climb, it's just numb.
But it has a great ride, gets super gas mileage, and is in all other ways a terrific car. I love the steering wheel. And the clutch feels just right to me.

Wow, it's so freaking tall! In my old car I can easily palm the ground from the driver's seat. In the Sonic I can just barely touch the ground with a fingertip if I stretch.

This is replacing a 2001 Prizm as my daily driver.
The Prizm has 4 wheel ind suspension, real hydraulic steering, is 391 lbs lighter and 6” shorter, riding on 195/60-14 and KYB struts. It has a slightly better power to weight ratio and similar measured 0-60 time.

The Sonic is obviously faster than the Prizm on the open road, and has more lateral grip. But it kind of feels like it's going to fly off the road at any moment. It is upset by mid corner bumps and is soft and grippy enough to get rebound oversteer when the suspension unloads. Add to all this the complete lack of steering feedback, and it's kind of scary to drive fast on a back road. The Prizm may have somewhat lower limits, but I can fearlessly drive it at 9/10s.

One of the higher limits of the Sonic is its power and speed. Although the Prizm has a (very slightly) better power to weight ratio and a similar 0-60 time, the Sonic has way more top end. The Sonic's measured 0-100 time is significantly quicker, and its top gear acceleration is phenomenally superior. The Sonic is very relaxed on highway. Turns 2500 rpm at 83 mph, which is right at the beginning of the torque plateau. The cruise control has no problem or drama holding the set speed up hills.

But it seems to build its speed rather slowly, like it's gathering momentum. Maybe that's turbo lag, maybe that's mass. But when you downshift and mat it, there is no punch. I would prefer a more immediate throttle response when I go to overtake someone on a two-lane. But wow, once it's on the boil the Sonic is pretty fast. It would just skunk the Prizm in a road race. But, tearing around town under 40mph? Prizm might win that one.

Our other car is a Buick Verano. Of the three cars, the Sonic is the softest. The Buick has the taut, yet comfortable ride that I wish the Sonic had. When jouncing the cars, the Sonic is significantly easier to push down than the other two, and is the only one I can get an extra bounce out of.

I know I'm really ragging on the Sonic's suspension but I think it is the one thing holding the car back from being best in class. Kind of sad that my wife's base-model Buick has a more assertive ride and handling setup. I probably shouldn't complain about it so much. A sport suspension is an available option, so maybe the base setup is softer than it would be if there was no sport option. Besides, the ride is super comfortable if you are just tooling around. I would have got the sport suspension but the $700 installed cost is prohibitive and still barely lowers the car.

Did I mention how tall it is? Like a small crossover or a Juke even. And the wheel gap is huge: can stick my entire fist in there.


Conclusion:
Love the car. Very happy that I bought it. But wish it was shorter with less tippy handling, and better throttle response would be nice too.



Planned upgrades:

1. remove snorkel and hard pipe the stock airbox
this will net 3 hp and 4 tq (according to BNR page on the MPFab intake)
this 2% boost puts power to weight ratio just over that of my old car
might also improve throttle response
parts already ordered

2. lowering springs – 1.25”
this addresses my primary concern with the Sonic
want to do this asap, within a couple of months if possible
not sure if I want to go stiffer (Eibach) or keep near-stock spring rates (ZZP)

3. window tint
looks cool, and practical too
had it on my old car, so I'm used to it

4. maybe some black bowties to go with the tint?

5. Upgrade to 205/60-15 tires on the stock rims
this is at least a year out

6. RS struts and shocks

7. rear axle brace or sway bar
time will tell if I actually will want this
further reduce body roll
really like the elegance of the axle brace, but leery of drilling into axle

8. second cat delete
if won't throw code, why not

9. intercooler upgrade
improve both power and reliability? Sounds great.
pretty expensive so prob won't really happen though

 

[zomby woof]

I don't know what you've been driving, but the Sonic just plain handles with excellent feedback, especially for a subcompact car.

Tires and rims should be your first mod. Those 195 65's on 15" rims is probably what you're really feeling.

Look for some 17" take-offs with 205's, and upgrade to 225's after.

 

[spacedout]

I have an LTZ sonic with the 17in wheels, they seems more planted than the 15 and 16in wheel models I drove. I had a Gen1 Cruze previously(1LT RS 16in wheels) it had the rear Zlink suspension like your verano. On uneven pothole filled roads The Zlink really soaks on the side to side rear movement, sonic or even a cruze model without the Zlink both ride rough with rear side to side bouncing over the same road.

With the Sonic there is some over-steer when you have to make a tight turn on gravel or snow, not something I've ever experienced to this degree with a front wheel drive car. No need to use the ebrake, just turn the wheel a bit more if you want the back to rotate. Unfortunately this behavior makes my sonic much less stable/predicable than my gen1 cruze was in the snow. I've had two different tires over 60,000 miles on my sonic, no change in the physics.

I put on up to 4000 miles a month, so with the somewhat unpredictable handling in snow/wet I may end up trading my Sonic in the next 1.5 years(some times I get under-steer like one would expect with a FWD, other times massive over-steer).

Currently I'm considering GM's other good economy car, the 2.0T 2016+ Camaro. It has DOUBLE the horsepower and torque of the sonics 1.4T(2.0T has 275hp and 295lb-ft of torque) and only looses 5MPG to the sonic. It also has a 19 gallon fuel tank vs 12.2 so it actually has better range, and with Rear wheel drive at least the handling with always be predicable(over-steer).

 

[Hectic]

If you're unhappy with the current ride, may I suggest the GM lowering kit option. It stiffens it up quite a bit, you get some nice feedback.

On my old 2012 LT, I had the ZZP lowering springs, and they bounced quite a bit on stock struts. On my 2017 Premier I have the GM lowering kit, which changes out all four springs and the rear struts. I would strongly suggest it. While it may not lower as much as say Eibach / ZZP springs, it makes a world of difference.

 

[K-Bob]

@ zomby woof: This is my first personal car with electric steering, and it provides almost zero feedback. Very scary not to feel the steering load increase with Gs. Have no idea what the front wheels are doing. Today I ran over something in a parking lot with one front wheel while turning. It bounced the car but didn't even nibble the steering wheel. The electric steering is just something I will have to get used to.
I am completely opposed to 17s. All other things being equal, smaller rims provide better performance. This has been shown in back to back testing. And, for example, the upgraded high-performance wheels for a Caterham are down-sized 13s. It is also verified in the automotive press that the upsized "performance" wheels on the Alfa Romeo 4C actually screw up the handling. The biggest setup for a Sonic would be 225s on 16" rims. It's all about unsprung weight and rotational mass/inertia, and the suspension's ability to control them.
For my purposes as a daily driver, I think 205/60-15 are appropriate. I realize the O.E. tires are faily lowly regarded and I plan to replace them in a year or so.

@spacedout: @Hectic:
I had another car in the past with a twist axle in the back and it handled ok. I think the Sonic just doesn't have enough roll stiffness, or that it's center of gravity is too high. It's hard to say which is the primary culprit. Generally in a small light car you can get away with a softer suspension. And my old car isn't exactly tight. So I'm thinking the height is what is getting to me most.
I was really thinking of getting the ZZP springs, they are supposed to be pretty close to stock spring rate. But you say they made it bounce too much. So maybe I'd like the Eibach better? Eibach claims to do their testing with the stock struts/shocks. I really want the 1.2" drop.
I think maybe Eibach/ZZP lowering springs with the shocks and struts from the GM Performance kit are the way to go. Would love to have those part numbers.
I don't want to make the car hard, or an autocross machine. It is a daily driver/commuter mostly, but I do like to hustle down the backroads sometimes.
I am not concered about its wanting to oversteer a bit. That is a good trait, but the tippyness makes it feel scary.
Would love to hear more discussion on Eibach vs ZZP springs.

 

[dannyg]

The manual in my 2015 says to run 38psi all around. Maybe bump up the tire pressure, see if you notice a difference?

I have the same 15s that you do, I find the ride comfortable and reasonably crisp, have no desire for 16s or 17s...but wouldn't mind trying 205/60s to see the difference.

 

[zomby woof]

I'm glad that after 900 miles on a new car you have it all figured out.

Good luck to you my friend.

 

[K-Bob]

I have adjusted the tire air pressure so they are running 38 ft and 36 r when hot.
I'm thinking a little more tire compliance might help. Going to drive it for a week or so with these pressures and see how it is.

I am beginning to think GM has spec'd really high air pressures for MPG reasons, and then softened up the suspension to compensate. Hmmm.....

For reference, I run 32ft 28r in old car that weighs 2400 lbs.

 

[Hectic]

@ zomby woof: This is my first personal car with electric steering, and it provides almost zero feedback. Very scary not to feel the steering load increase with Gs. Have no idea what the front wheels are doing. Today I ran over something in a parking lot with one front wheel while turning. It bounced the car but didn't even nibble the steering wheel. The electric steering is just something I will have to get used to.
I am completely opposed to 17s. All other things being equal, smaller rims provide better performance. This has been shown in back to back testing. And, for example, the upgraded high-performance wheels for a Caterham are down-sized 13s. It is also verified in the automotive press that the upsized "performance" wheels on the Alfa Romeo 4C actually screw up the handling. The biggest setup for a Sonic would be 225s on 16" rims. It's all about unsprung weight and rotational mass/inertia, and the suspension's ability to control them.
For my purposes as a daily driver, I think 205/60-15 are appropriate. I realize the O.E. tires are faily lowly regarded and I plan to replace them in a year or so.

@spacedout: @Hectic:
I had another car in the past with a twist axle in the back and it handled ok. I think the Sonic just doesn't have enough roll stiffness, or that it's center of gravity is too high. It's hard to say which is the primary culprit. Generally in a small light car you can get away with a softer suspension. And my old car isn't exactly tight. So I'm thinking the height is what is getting to me most.
I was really thinking of getting the ZZP springs, they are supposed to be pretty close to stock spring rate. But you say they made it bounce too much. So maybe I'd like the Eibach better? Eibach claims to do their testing with the stock struts/shocks. I really want the 1.2" drop.
I think maybe Eibach/ZZP lowering springs with the shocks and struts from the GM Performance kit are the way to go. Would love to have those part numbers.
I don't want to make the car hard, or an autocross machine. It is a daily driver/commuter mostly, but I do like to hustle down the backroads sometimes.
I am not concered about its wanting to oversteer a bit. That is a good trait, but the tippyness makes it feel scary.
Would love to hear more discussion on Eibach vs ZZP springs.

I had the lowering kit put in before I picked up my 17. The ride quality is much better compared to what my 12 was stock, or with just the ZZP springs in it.

They are incredible to drive with, and you have amazing control, very little body rolls.

 

[K-Bob]

The GM lowering kit is a well engineered package. The more I think about it, the more I will probably go with ZZP springs and the GM struts/shocks from the lowering kit.
So, basically the GM kit, but with .7" more drop.

ZZP even sells this as a set, although my budget dictates I do it piecemeal (TT&L from buying the car pretty much tapped me out).

I will get the springs first and see how it rides, then get the dampers later if I think it needs them.

Wish I had gotten the lowering package on the car when I bought it, but it wasn't included in the awesome deal I got on the car.

 

[mtbrdad]

Wow great review of the sedans. I own about 6 of these as fleet vehicles and you hit dead on what I've thought about the ride, handling and braking of these cars.

 

[andrewjc]

K-Bob you may want to consider the ZZP sway bar. It's a direct bolt on, no drilling required. I have it and it does make a difference.

 

[MORTIS]

I had the lowering kit put in before I picked up my 17. The ride quality is much better compared to what my 12 was stock, or with just the ZZP springs in it.

They are incredible to drive with, and you have amazing control, very little body rolls.

I'm also interested in the GM suspension kit. You say "It stiffens it up quite a bit" but also say the ride quality is much better than your stock '12.
I very much prefer a tight handling car but I also like a refined and comfortable ride, which is possible with a well enough engineered suspension. How would you describe your experience with your Sonics with those seemingly opposing qualities?

 

[$ub$onic]

The GMPP kit is basically RS struts, a little different damping on the rear shocks and lower springs. Nothing too fancy.

We have RS stuts with eibach springs on our 17 and the ride is excellent compared to my other 2 Sonic's on coilovers

Sent from my S60 using Tapatalk

 

[K-Bob]

So which do you guys (esp. $ub$onic) recommend: the full GM kit or the RS dampers with Eibachs?

After 2300 miles I am starting to think Eibach is the way to go.
The car is just so tall and soft and tippy.
Since the Eibachs are progressive, they should give a decent ride, right?
And Eibach says they work ok with the stock dampers.
I do plan to get the GM Perf. dampers, but that will have to wait a few months.

On the other hand, the GM springs should be pretty high quality. The car still looks good with the 3/4" drop. And they shouldn't throw the camber out of spec. But will the car still squat and lean too much?

My biggest concern about buying the GM or ZZP springs is that I'll drop what for me is a substantial amt of money and still be dissatisfied with the handling.

 

[zomby woof]

You won't be happy with the handling until you get rid of thos 195 65's. Mine is completely stock and handles good - really good on the stock 17's.

 

[K-Bob]

Just put Eibachs on with the stock dampers, and it handles pretty good now.
With the Eibachs it drives like it should have driven right out of the box. What is wrong with GM?
Only had them for a day now, but seems there is no ride quality penalty, in fact the ride is improved I think.
But seriously have to watch the ground clearance. Only 4.24"clearance on the chin spoiler now. Scraped on an ally I pull into every day. And I doubt gravel roads are going to work anymore.

I'm satisfied for now, but I may get the GMP dampers later.

 

[andrewjc]

K-Bob Thanks for the update. I'm just a little surprised that you did not replace the struts because you had the suspension taken apart. Big props on DIY route!

 

[K-Bob]

Will probably add the GMP struts/shocks later. It's basically a money thing, honestly, so maybe tax return time will bring dampers.
Besides, I wanted to see how it is with just the springs.
Several guys on here seem to have Eibachs with the base dampers and like it that way.

Will try to post decent before and after pics in a few days.

And will post updates as I think of them.