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Discussion Starter · #1 · (Edited)
Little over 2 months on brand new 2018 Volt.
I am quite disappointed with this car's emergency manoevuring ability. Its very sloppy, almost wobbly. Gives that mushy inconfident feeling in a hard steer at highway speeds. Its especially worse when the car is loaded with passengers and/or cargo. Tire psi on dash shows 38 all around.

Is this due to the stock tires ? Or is the suspension inherently lacking ? or both ? or is something wrong with my car ?

The only time I have experienced this kind of handling is when the struts and shocks have worn out. This type of handling would get a very low score in a slalom lap test on the track.
My comparison is not with any fancy sports coupe but regular sedan (accord v6) and suv (acura mdx). I have no complaints on the handling of these two cars. T
 

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In my opinion, it is the OEM tires. Also, please try increasing the tire pressure to about 44 psi. I think you will notice a big improvement in emergency handling with that change.
 
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Discussion Starter · #3 ·
While I don't expect it to be nimble like my TR7 (saved my life once) I think it could well be down to tires (low rolling resistance vs. performance). Never had a emergency maneuver yet although nearly side swiped this morning as the girl driver wanted to cross several lanes of traffic to make an exit and didn't hear me come up to her as she was accelerating from a stop, she ducked in behind me at last minute to make her exit. Scared the wife. Nothing I could have done in that instance anyway.
 

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I have no complaints with the handling of my 18 Volt, but it's never had more than two people and generally I drive alone. My tires are at 44 psi.
 

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Check the lug nuts. Make sure cargo is tied down firmly. Everybody belted. Use recommended higher pressure for max vehicle weight. Check for loose nut between seat and steering wheel.

It's a heavy car when loaded with higher CG than unladen. Like other cars, you adjust your driving style accordingly.

I have no problems with 5 people in the car, nor 2 people at 101 mph in crosswind. Or autocrossing at the limits of what the car is capable of, like violent slaloms.

But I can also make folk nauseous if I want in a tight Corvette. I just drive jerky deliberately. Smooth is fast, no matter what car.

As far as lap times, when a Tesla Model S shows at an AutoX, I can normally cut very similar lap times. But neither one is a sports car.
 

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Tires, suspension, or .... driver? :) Just saying ...

But my guess would be tires. Performance tire can be more aggressive, but you will lose 5+ miles range.
 

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The Volt seems to handle fine around town with 43 PSI in the tires.

Given the weight and LRR tires, I worry a little about an emergency maneuver at highway speeds.
 

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Boost the tire pressure. Cars sold in the US have OEM recommended tire pressures based on comfort, then safety, then handling. As a result those of us who want better handling, which also results in better safety, need to boost the tire pressure.
 

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I think my 2017 handles great in any situation. Tires were at 42 but our roads are pretty bad right now so I took them down to 38 for now. Can’t say I notice a difference in handling....


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I understand the OP's point, and agree it is likely the tires (although I think the boosted electric steering may struggle a bit on sharper turns with rapid deceleration). My Gen 1 Volt had less body roll and was heavier--better maneuvering, but less comfort in some choppy roads. Different tires on the Gen 1 made a big difference and when these OEMs are done, I'll be switching and expect better performance.

I had a situation where I had to slam the brakes and rapidly change lanes to avoid a stopped car at 75 MPH and the Gen 2 Volt had insane body roll in this scenario and the tires squealed like mad. However--the car recovered and a bad situation could have been much worse.

Now, since these situations are rare and I would never A/B test this with other cars, I'm not sure how others would respond. My guess is this same scenario in a prius would have been much, much worse.
 

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I highly doubt anybody here is pushing their car hard enough to really reach the limits of the tires. The limits are far higher than almost anybody would ever feel comfortable actually pushing a car on the street.

I'm guessing from the OP's phrasing that he's complaining of the lack of aggressive rebound damping in the shocks and relatively soft front roll stiffness. These things give a comfortable ride, but they definitely make the weight transfer and suspension taking a "set" a relatively slow process compared to more "sporty" offerings. The Volt also seems to run essentially zero negative camber front and rear, which doesn't help, because you only generate lateral force as the tire carcass is distorted to the side. Running negative camber gives the tire an innate "thrust force" due to the tire being canted slightly inwards, which makes a car turn in much more readily and generate more ultimate grip on that axle (within reason, there are diminishing returns, and extreme negative camber can take away grip in many instances).

I plan on putting a hair of negative camber in the front of my car via "camber bolts" or "crash bolts" as some call them. Probably around -0.7 to 1.0 degrees is fine, and should even out the wear on the outside shoulder I see because I drive a little... ahem... more spiritedly in the twisties than most Volt drivers likely do. I imagine it'll improve initial turn-in and ultimate front end grip at the limit.

That said, negative front camber will push the need for zero or near zero front toe, otherwise most people are likely to suffer increased inner shoulder wear. Most people here would not like the feeling zero toe gives on the road, as it will make the car wander a bit and grab ruts in the road much more. I imagine it won't be horrible in the Volt with the relatively narrow tires, but it'll definitely increase from the "lazy" dead-straight tracking the stock alignment gives.
 

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About a month ago I had to do not 1, but 2 emergency maneuvers dealing with the same teenage driver. She first cut across two lanes at a freeway exchange to get on a different freeway, cut me off so first one wasn't bad, just had to slow down and let her go. She then decides the original freeway is what she needed, cut across the median of the freeways and almost side swiped me, so had to cut right (no one in that lane). Bottom line, the Volt handled well.

These cars have a low center of gravity due to the traction battery so I find they are reasonably well planted. Yes, LRR tires aren't as good as performance sport tires, but I find them adequate. I run them (OEM Michelins) at 42psi cold. They run up to around 44 to 45 hot. I've found 42psi to be perfect and I've played with a few different cold psi settings. No complaints on the Volt handling from me.
 

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pfm: Please describe what you really mean by "emergency maneuvering ability". What sort of driving maneuvers were you attempting to do exactly?
Exactly! And how often are you doing them? The Volt is no sports car, but for a sedan it has a low center of gravity, and handles very well in everyday driving. I've had to make some quick maneuvers (given that my Volt seems to be invisible), and found no issue with slalom behavior what so ever. There is no way that any SUV (short of a maybe a Jeep SRT) is going to handle better than the Volt. Studies done by DOT in the 60s and 70s demonstrated overwhelming that cars outperform drivers trying to control them. And since then cars have gotten a lot better -- drivers not so much :(
 
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Discussion Starter · #17 ·
I saw lots of folks using 40+ psi for tires. The factory recommended is 36. I have mine around 34/35. Is it better to go 5+ psi over recommended number? That seems a lot to me, but maybe I don't know what I am missing here.
 

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I saw lots of folks using 40+ psi for tires. The factory recommended is 36. I have mine around 34/35. Is it better to go 5+ psi over recommended number? That seems a lot to me, but maybe I don't know what I am missing here.
The recommended tire pressure is printed on the DOT label that is located on the B pillar of the driver's side door. The maximum tire inflation pressure is molded into the sidewall of the tire. You can safely inflate up to the maximum pressure (you need to account for the tire pressure reading when the tire is hot.) Generally under inflation by 1-2 lbs is not a safety risk but too low tire pressure will cause the tire to run hotter and also contribute to excessive wear on the inner and outer edges of the tire. Both over and under inflation can affect handling of the vehicle. The tire pressure monitor system (TPMS) monitors over inflation as well as under inflation as both are unsafe.

One approach would be to inflate the tires to 40 - 42 PSI (when cold) and then reduce the tire pressure by 1 lb each day (use an accurate tire pressure gauge) until you find a setting that provides the best combination of EV driving range, ride comfort, handling for your driving. Many have found that for the Gen 2 Volt OE Michelin EnergySaver AS tires 40 PSI (cold pressure reading) provides the best combination of range and handling. The Goodyear tires on the Gen 1 Volt can be safely inflated to higher tire pressure than the Michelins. Personally I have found that I prefer the way the Gen 2 Volt rides when the Michelin tires are inflated to 37 - 38 PSI although I admit I will add air in the late fall until the tire pressure is 39 or 40 PSI knowing that tire pressure will drop 1 -2 PSI for every 10 degrees drop in ambient temperature. In the early summer I will lower the tire pressure to 37 PSI (cold reading).
 
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Discussion Starter · #19 ·
The recommended tire pressure is printed on the DOT label that is located on the B pillar of the driver's side door. The maximum tire inflation pressure is molded into the sidewall of the tire. You can safely inflate up to the maximum pressure (you need to account for the tire pressure reading when the tire is hot.) Generally under inflation by 1-2 lbs is not a safety risk but too low tire pressure will cause the tire to run hotter and also contribute to excessive wear on the inner and outer edges of the tire. Both over and under inflation can affect handling of the vehicle. The tire pressure monitor system (TPMS) monitors over inflation as well as under inflation as both are unsafe.

One approach would be to inflate the tires to 40 - 42 PSI (when cold) and then reduce the tire pressure by 1 lb each day (use an accurate tire pressure gauge) until you find a setting that provides the best combination of EV driving range, ride comfort, handling for your driving. Many have found that for the Gen 2 Volt OE Michelin EnergySaver AS tires 40 PSI (cold pressure reading) provides the best combination of range and handling. The Goodyear tires on the Gen 1 Volt can be safely inflated to higher tire pressure than the Michelins. Personally I have found that I prefer the way the Gen 2 Volt rides when the Michelin tires are inflated to 37 - 38 PSI although I admit I will add air in the late fall until the tire pressure is 39 or 40 PSI knowing that tire pressure will drop 1 -2 PSI for every 10 degrees drop in ambient temperature. In the early summer I will lower the tire pressure to 37 PSI (cold reading).
Thanks! Yes I am referring to that DOT label and I see 36 there. As you mentioned, range and handling is important, but I care also about an even tire wear. Setting to 40 psi will provide a more even tire wear, compared to 36?
 
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Discussion Starter · #20 ·
pfm: Please describe what you really mean by "emergency maneuvering ability". What sort of driving maneuvers were you attempting to do exactly?
I had a situation where I had to slam the brakes and rapidly change lanes to avoid a stopped car at 75 MPH and the Gen 2 Volt had insane body roll in this scenario and the tires squealed like mad. However--the car recovered and a bad situation could have been much worse.
The title of the thread was chosen deliberately. Because if it read "subpar handling" it wouldn't have conveyed the situation accurately. Sure it "handles well" for the most part, but it is in this specific scenario that is the real test of "handling".

Once someone cut in front of me and at another time when I was changing lanes/merging the guy behind me jumped lane and merged before me forcing me to move out of the lane and back in. One more - traffic in my lane came to a sudden stop and I had to swerve to the shoulder.
These situations are pretty common around here.
 
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