Cherrier Vivace & Tograc

I pronounce it tog-rack, but maybe that's just a weird australian accent influence.

 

I have an issue with the rear brakes on the Cherrier overheating. It only seems to happen when you use the wide-track suspension with rally brakes. You can recreate it if you come to a complete stop using the handbrake and keep holding it after you've stopped.

Here is a video of how to reproduce the bug as well as the config of the car I used when I discovered the bug.

 

I pronounce it "Toag-rack" Like "Toad" but with a G.

idk, I pronounce half the cars names wrong.

 

I pronounce it that way too

 

What would you people say about how

"'Strut Bar"

and

"Chassis Stiffening"

affect vehicle handling?

 

A strut bar does not affect handling I do not think. It's main job is to roughly prevent stuff like this:

​

And chassis stiffening gives the car a bit of understeer (which helps the vivace with grip), and it makes the car more stable on turns

 

I mean, you could've done some easy research yourself, but:
https://en.wikipedia.org/wiki/Strut_bar
This should help.

 

This is not true, its main purpose is to "stiffen" the strut towers, preventing excessive deformation which could affect handling.

 

On this episode of "DriftinCovet Opens Up Paint.Net and Hacks Together A Restyled Game Car to Get All the Agrees",

I literally took the tail light from the blue Vicrock and slapped it onto the front ends of the red Vicrock and two Hogwashes, then hastily covered up the lower headlight portions on all the cars.


I think it looks better now.

 

I did the research but I am struggling to notice a difference in handling. Now, to be fair, I am driving with a keyboard but even when you corner with the maximum steering angle there does not seem to be a difference in roll angle, weight distribution or G-forces.

 

All of the turbos are unable to adjust boost pressure, all of the ECUs are unable to adjust boost-by gear, idle RPM and stuff. The AWD Tograc is restricted to 0.7 bar boost at 1st gear making climbing 45degree slope impossible unless you reverse gear. The rally transfercase is not adjustable because the "variables" had been deactivated via some "//"

Disappointed.

 

Well, I just don't know why limit 1st gear boost in an underpowered AWD vehicle.

 

Thanks for you demonstration.
The problem is that limit boost in 0.7bar is not necessary at all in an AWD, since electronic diff brake is less energy efficient than locking diffs, you'll need more engine power to climb a slippery or uneven incline. According to my off-roading experience in Utah, the Tograc can climb some incline driving is reverse, but cannot climb the very same incline when driving forwards due to the lower boost.
Also I found that when stationary or almost stationary in 1st gear(clutch assist or DCT) and hit the gas, 50% gas and 100% gas makes little difference.

 

Define underpowered? The lowest power option for AWD in the Tograc is the 150 HP turbo diesel... an engine with superior torque characteristics compared to the next more powerful 160 HP turbo gasoline one.

I fail to see what is underpowered about 150 HP turbo diesel. Please keep vehicle class and average buyer in mind..... this isnt and was never meant to be a climb 45 degree angle serious off roader.

You should see it at what it is. A car that just like in real life will be moving on asphalt in 99.9 of its driving life.

This is an car meant for onroad use first and foremost.... and for that.... I personally think its actual offroad performance is suprisingly good. Especially for something that basically has a asphalt suspension that is adjusted to be better at offroading in additition to some software adjustments.

Many modern cars ECUs limit available power output in low gears as it allows the manufacturers to use less durable = cheaper drivetrain components without hurting long term reliability. Added to the fact that in normal driving conditions - again, keep the average buyer and usage scenario of Tograc in mind - there is simple no reason at all to torture the drive train like that unless you really really want to torture it.

Even reduced power output (by means of boost or otherwise) is more than sufficient to make tires slip on asphalt and has traction control intervening.... from a normal driving standpoint there is zero reason to allow maximum torque and power output in first gear. As Nadeox just demonstrated you run into grip issues long before running into power issues.

Yes... brutal offroading is different. But then again.. this car conceptually was never meant for that.

A differerent gear ratio could mean that engine output is higher even with the same boost. In any case, coming from real life perspective again.... there is far less reasons to protect reverse gear from material torturing drivers because reversing in general is done at low speeds and low power output. A lot of people will trash their car hard in 1st gear to achieve strong acceleration but almost nobody will go full boost in reverse... far to dangerous and uncontrollable.


The expected offroad scenarios of vehicles like the Tograc only rarely involve much worse conditions than any average everyday car can handle.

I just think that you are having unrealistic expectations about what the Tograc is in principal meant to be. You wouldnt rate a rock crawler for its race track performance... why do judge an 99.9 % asphalt only car by its performance in brutal offroading..... offroading that most owners would never allow you in the first place in rightful fear about potential damage to their expensive toy.

 

And they almost never tell the true power rating in 1st gear, those car manufactures/dealers always tell you the power at 2nd gear and above, as "rated power", while doing limitation in their ECU(and using less reliable drivetrain) secretly.
That's a deception.

 

One might argue that most customers dont even understand the relation between torque and power and that in 1st gear significant differences only occur when you rev it to peak power and then - brutally - engage the clutch. Which makes traction control intervene even in rather modestly powered cars because changes are, you are not getting that power to the wheels at standstill without significant slip. (And generous amounts of clutch, drivetrain and tire wear) In a more realistic scenario, accelerating from a standstill to highway speeds at full power output will not see much use of the first gear and the difference between full boost and limited boost as such is probably very small.

Keep in mind that in an naturally aspirated engine you are far more affected by ICEs principled power band. Starting in first gear and revving the engine all the way to peak power in a NA gasoline engine of 100 HP rated power actually looks like this:

1000 RPM = 17 HP
2000 RPM = 33 HP
3000 RPM = 50 HP
4000 RPM = 67 HP
5000 RPM = 83 HP
6000 RPM = 100 HP

You are not really getting those 100 HP much.... in fact... for most of the time you are getting far less. It should be noted that in reality, this simple model isnt entirely accurate.... torque development in an NA gasoline engine means that it will have slightly more power at mid revs to peak torque than estimated here. It still perfectly describes the principle and helps explaining why turbo diesels with less rated peak power often feel much more powerful than gasoline engines of comparable but superior peak power. A 90 HP turbo diesel will have those 90 HP at 4000 RPM.... where the 100 HP gasoline engine only manages arround 67 HP.... granting it superior performance in everyday driving. Only in the area between 5500 - 6000 RPM does the gasoline engine actually has its 10 HP power advantage.

Modern turbo engines meant for economy first primarily increase the power output at low to mid RPMs because this is what makes the car feel powerful in everyday driving. A wild estimate might look something like this:

1000 RPM = 20 HP (still mostly in turbo lag)
2000 RPM = 45 HP
3000 RPM = 60 HP
4000 RPM = 80 HP
5000 RPM = 85 HP (turbo effect starts to dwindle)
6000 RPM = 100 HP


With the power band in mind and the turbo advantage in "power feeling" already being quite notable.... you would be hard pressed in real life to make the case for non limited boost in 1st gear. The difference is going to be very very small and probably not even noticable outside of a race track or extreme driving.

Meanwhile, as a buyer of used car I have a vested interest that the car does not allow you to torture its drivetrain unduly. And while I fully agree with you that manufacturers should make drivetrain components as reliabe as possible (with a nice safety margin on top) the reality is that this is a market where manufacturers haggles about the 3rd digit behind the decimal point for most parts. They would most likely not use a more durable drivetrain and instead think that realistically even when undersized it will casually live past the warranty period in most cases. Most people dont trash their cars, especially not in such an average commuter vehicle.

Yes, they should use a drivetrain that can handle full power in 1st gear.... but they wont and I have an above average chance of being the winner of a expensive repair bill and as such have to say that I favour them - knowing their dirt cheap hardware - to software limit the stress on it.



Lasty, one might argue that it isnt a deception as we are talking about peak engine power output and not peak wheel power output. Seing that an ICE only reaches full power for a very limited amount of time one might seriously argue about the value of getting all worked up about the boost pressure.


I dont mean to attack you, I just disagree with your opinion in this case.

 

Informative post. Could you please do the following test? My saying that it cannot climb 45degree slope didn't specify the road condition clearly, sorry. The road condition is about 35 degree slope uneven terrain.
Put the AWD tograc 160 against a wall or making it stationary. Apply throttle to boost to 0.7 bar. Then you'll notice that 50% and 100% engine torque are almost the same.
Mod the ECU so that 1st gear boost is the same as 2nd gear boost, then use the diagonal ramp test, set the ramp to about 30degree.
As shown, limiting the boost to 0.7 fail the test because of insufficient engine power.

This is because eDiff or traction control is less energy efficient than LSD or locking diff since braking dissipate power as heat. When off-roading with open diff, more engine torque is required, compeared with vehicles w/ LSDs.

Also I didn't say that the drivetrain should be "as reliable as possible", the Arsenic use the same 7DCT and driveshaft IIRC, the deception I meant is that the rating of the engine torque/power should be in that RPM range with full throttle, but if you are in 1st gear, the engine torque is not rated torque even in that RPM range with full throttle.

 

The only thing I wish is that there was a traditional automatic on the less-powerful engines. Peugeot and Citroen are putting that new 8-speed automatic in basically everything that has 100HP or more. But it seems like the higher-powered European hatchbacks are using a DCT.


It's a great car, devs! I like it a lot.