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Discussion Starter · #1 · (Edited)
I'm not the owner of a Caliber just yet, but I want to know this before I decide on the SXT or the R/T:

Supposedly, the characteristics of the CVT in the Caliber hinder the vehicles overall performance. My understanding of CVT technology in general is that when accelerating aggressively, the the CVT ratio should allow the engine's rpms to hover around the peak horsepower of the engine, providing maximum acceleration. I also imagine that when towing or climbing, the CVT should allow the engine to hover around the peak torque.

Naturally, because this is a small engine, you don't want to be spinning 4k or more rpm at all times, but does anyone know if reprogramming the CVT's computer (I assume it has one) will allow better utilization of the engine's performance values? Really, more to the point - does anyone know if reprogramming the CVT is possible?

Or - does anyone who owns a Caliber disagree with the reviews I've read about it? They assert that cars that are (admitedly) 300lbs lighter but have ~50 fewer horsepower are posting similar acceleration times, and that especially the R/T should be much faster given that it puts out about 175 horsepower. I only test drove the SXT with the 2.0, and was unimpressed with its acceleration, although I liked the car overall (and despite the cheap plastic used on the interior, too).

So basically, if this is an option (I'm new to the CVT world) in the future, I would probably go for the R/T - but if there's no way the CVT could be altered, I would rather pay less money for an equally slow car.
 

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For max performance, the Caliber CVT goes to like 6000 RPM when you mash the go-pedal all the way to the floor past the "click" in the pedal. The idea is to go to max Hp, not max torque, since that will get you the best accelleration. The JATCO CVT does have it's own trans computer which can be reprogrammed (there have been a couple of software updates for the trans controller since the caliber first launched). That said, I wouldn't expect anyone to be coming out with any kind of "performance" flash for the CVT trans. Since it already spins the engine at peak power when you floor it (well, pretty close at least), there's not much performance to be had anyway. The problem with the CVT seems to be that 1st gear isn't very steep and maybe it needs a high-stall torque converter or something.

Also, as far as 2.0L versus 2.4L performance goes, since the CVT should let both of them run at "peak" power, the nice fat torque curve of the 2.4L won't help you too much. The 2.0L is like 160 Hp versus 175 for the 2.4L, right, so the 2.0L has 3000lbs/160 hp = 18.75 lb/hp, 2.4L AWD R/T has 3300 lbs/175 Hp = 18.87 lb/hp. This is why they perform about the same. Plus the AWD is taking some power to spin. Personally, I like the 2.0L CVT better, but you may want to wait to drive a FWD R/T (2.4L manual FWD or 2.4L CVT FWD). Those should be the real performance packages and should be available later in the summer...
 

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the car accelerates much faster than you think the cvt makes the car feel powerle3ss untill you look at the speedo and realize you are going crasy fast and you don't even think the car has started to move yet also the car is competly different with 5000km on it the car just keeps getting better
 

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Discussion Starter · #4 ·
Thanks, guys. I got to drive the R/T at my local dealer last night, and I liked it pretty well. My wife just got her approval for the car (it’s for her), so we’re going to go see what rate they’ll give us. If it’s low enough, and it probably will be, we will take the car home tonight. My wife isn’t a car nut like I am, so she doesn’t appreciate the relatively advanced technology under the hood – she just wants it to go – so I was the proponent for the R/T. (She was too once she found out that it was equipped with a sunroof)
Wayne: I definitely look forward to driving the car when it gets broken in. I expect your observation of the car feeling like it’s not moving is more than related to the absence of shifting up to an rpm below the power band and moving back into it, which would provide some inter-acceleration acceleration, if that made any sense. I had to keep reminding myself not to compare this car to my old Volvo 850 turbo. Compared to my Escort commuter, it was more than capable though I still felt the response to the accelerator was less than expected.
Tito: I understand that at WOT, for performance and acceleration you want max horsepower, but when I mentioned torque I wasn’t talking about acceleration. I’m sure you also understand that horsepower is a function of torque over time – torque and rpm are the only real measurements, horsepower is computed using these data. In real world driving, if you’re not flooring the gas everywhere then you’re relying on your low-end torque to motivate the car. According to the bore x stroke information on kbb.com, the 2.4L is an undersquare engine, which *should* produce more low-end torque than the squarish 2.0L – displacement notwithstanding – because it has more leverage over the crankshaft. Indeed, the 2.4 produces 24 more ft-lbs of torque 600 rpm lower than the 2.0, a 17% increase when comparing peaks. Although it “only” produces 14 more horsepower @ 172hp, it also is produced 400 rpm lower than the 2.0. This is a characteristic I prefer in my cars, and is how I made my decision. Torque ratings are more useful for determining towing/cargo weight capacity (along with suspension, etc), and since this will be the family vehicle in charge of getting my family and its stuff around on vacations, etc, torque played another part in the decision. Not that it’s towing capacity is so greatly increased or anything, but every little bit helps.
For others’ reference, hp = tq * (rpm / 5252). A torque formula can be derived as tq = hp * (5252 / rpm), for fun. I’m fairly certain this is for a naked engine that’s not driving accessories like A/C, power steering et al.
Also regarding the AWD, I was under the impression that it was an electronically activated part-time AWD system, so it shouldn’t be turning all 4 wheels all the time unless slippage on the front wheels occurs. I did read, however, that the AWD system may engage during heavy acceleration to assure the driver of good traction despite the nonexistence of wheel spin. Is this inference correct?

At any rate, my concern is really the sluggish feel of acceleration when not fully WOT. I don’t like to run my cars WOT, so I feel I should be able to reach, say, 3500 or 4000 rpm under 50% or greater pedal depression. My original post may not have really gotten to the point; I was most interested in CVT programs that would help increase vehicular response by “downshifting” proportionally to the depression of the gas pedal. If the car already does this, then I would prefer the program shift the gear down a bit faster based on the same input. In lieu of this option, at least the R/T has the Autostick feature (another selling point for me).
 

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OK, I get it now -- you'r talking about how the car drives at part throttle where the 2.4L "should" help. Sounds like Chrysler is playing the fuel economy game and keeping the RPM so low that you negate the benefits of the 2.4L (i.e. for the same pedal position, 2.0L and 2.4L deliver similar power, but the 2.4L is just at a lower RPM -- end result is similar performance). If you could figure out how to get the 2.4L up at the same RPM as the 2.0L, it should feel better. Kind of like a shift kit for a CVT -- delay the "upshifts" a bit so it drives around better. Probably a good idea, but I guess you're stuck with autostick on that. I'd also be a little scared of any aftermarket trans flash for the CVT. Since the computer controls how hard the belt is grabbed, I ould think it'd be easy to make a mistook and toast the tranny. I agree that it would be pretty neat if Mopar came out with a "sport" transmission ECU that moved the "shift" lines up a bit -- especially for the R/T (which I don't think feels all that sporty). Come on Mopar -- hook us up with CVT sport mode (or maybe a performance/fuel economy switch of some sort?)

As far as AWD goes, the Caliber is an active computer controlled system, but it's basically just a computer controlled clutch at the back of the prop shaft (before the rear diff). so you still gotta lug all that extra weight around (~300 lbs?) Even worse, you have to spin it...

Good luck on whatever decision you make!
 

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waynet said:
the car accelerates much faster than you think the cvt makes the car feel powerle3ss untill you look at the speedo and realize you are going crasy fast and you don't even think the car has started to move yet also the car is competly different with 5000km on it the car just keeps getting better
I have also noticed that...At first I was like "what the hell? Where's the umph in this thing??"

But then looked at my speedometer and was quickly cheered up. Not only was I already at 67, but also felt as if I was only going 40 tops...this car rides very nice!
 

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waynet said:
the car accelerates much faster than you think the cvt makes the car feel powerle3ss untill you look at the speedo and realize you are going crasy fast and you don't even think the car has started to move yet also the car is competly different with 5000km on it the car just keeps getting better
EXACTLY. THIS IS HOW I EXPLAIN IT TO PEOPLE. THE CAR DOESNT REV TOO MUCH.. IT IS PRETTY MONOTONAL AND QUIET, SO I DIDNT FEEL LIKE I WAS GOING REALLY FAST, BUT ON MY TEST DRIVE I LOOKED DOWN AND WAS GOING 65 IN A 35 WITH OUT REALIZING IT OR TRYING TO SPEED AROUND.
 

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Discussion Starter · #8 ·
Actually, I got to drive the car for the first time since I test drove it before we bought it (It's my wife's car, she's still too excited to drive it at every opportunity, so I let her). The problem is still there; when I floor the gas (like merging) the rpms of the car don't shoot up like I would expect. I had the pedal literally to the floor (couldn't go anymore) and the engine was only turning 4k rpm. At that level I would expect the CVT to allow 6k rpm. Luckily, the R/T model has the autostick mode, so I was able to get the engine to the "sweet spot" for merging. I would still want to custom make a program to allow the engine speed to climb higher than it did, faster than it did; when I floor the gas, I don't expect to be holding it there for long to ramp the rpms up. Especially with the CVT, I expect the depression of the accelerator to correlate directly to engine speed.

Basically, the car could be much more responsive, and much more fun to drive. My original post was about the feasibility of programming the shifting characteristics of the CVT, and it still remains. Does anyone have any information about this or other CVTs and reprogramming?
 

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Sounds weird -- are you 100% sure you had the pedal all the way to the floor? I'm not trying to be a pain in the butt -- it's just that the caliber has this weird throttle pedal -- you'l push the pedal down so it feels like it's all the way to the floor (you'll feel it stop moving and kind of bottom out), then if you push a little harder, it'll "click" past a detent and you'll get full power, CVT "downshift" etc. I'm still of no use as far as CVT reprogramming goes. I wonder if the 2.0L and 2.4L programs are different? I'm thinking the 2.0L probably runs a little higher revs since it'll have less torque. Of course, I doubt you could find a guinea pig to try swapping parts....
 

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the Caliber sure changes demeanor when the "kickdown" switch is enabled (by mashing the pedal WFO :) ). maybe you guys are right, it is a sportscar deep down inside.

/wonders what, if anything, rigging up a manual kickdown override would accomplish on part throttle, etc.
 

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Discussion Starter · #11 ·
I'll see if I can't wrestle the keys away again to try, but I don't like the idea of pushing the pedal farther than it feels like it should go....but you say it exists, so I'll try it :)
 

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I;ve noticed that my Caliber has quite a bit more pick up after putting a couple 1000 miles on it. Totally different than when new.

I've also heard that the latest computer update for spark knock and on other update I'm not sure about greatly improve accelleration. Mines going in next week for a new muffler (exhaust ping noise) and the computer update.
 

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Denzien said:
I'll see if I can't wrestle the keys away again to try, but I don't like the idea of pushing the pedal farther than it feels like it should go....but you say it exists, so I'll try it :)
Oh yea! When you go past the detent, the tach jumps to redline and pretty much stays there, and awwaayyy you go! And you get some pretty startled looks from people when you're turning 6000 rpm and it never shifts, you just keep accelerating. Heh, heh. I love this car.
 
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