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Discussion Starter · #1 ·
I was very hesitant to put this post up, as it could lead to a result unintended by the author.

First off a disclaimer:

If you have no idea what fuse 17 does, please don't bother reading any further.

If you have no significant performance driving experience with a high powered rear wheel drive vehicle, please don't bother reading further.

Now for the rest of you, if you have any experience in this subject - or want to consider experimenting, read on.

Today, I began a series of unscientific performance runs in my 300C with #17 removed. I may do the same runs with our Magnum R/T as well.

Before I post up my first day of findings, I would like to see your interest by return post.

I would also like to know if this info is better off being discussed in Private Messages, due to the safety implications.
 

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Northern Rider said:
I would also like to know if this info is better off being discussed in Private Messages, due to the safety implications.
Too late - might as well talk about it - people will go out ant try it anyway, might as well be informed.
 

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I posted in LX that I tried this and it actually slowed my times because they car wouldnt stop spinning till it got to 3rd gear.
 

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Northern Rider said:
I was very hesitant to put this post up, as it could lead to a result unintended by the author...

Before I post up my first day of findings, I would like to see your interest by return post.

I would also like to know if this info is better off being discussed in Private Messages, due to the safety implications.
I, for one, am most definitely interested in seeing your findings, and sharing some of my own with you. And I understand your caution re. open posts on "non-factory-sponsored" topics on this forum. It's your call, either way works for me.

And it's a shame that, beyond your initial disclaimers, one must even have that inner debate as to how much sensitive information to release due to valid concerns about how such information may be received and treated here.
 

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Tire pressure

300CGuy said:
I posted in LX that I tried this and it actually slowed my times because they car wouldnt stop spinning till it got to 3rd gear.
Thanks for your contribution.

What pressure had you lowered your rears to, 300CGuy?

Were you running your stock Conti's? How many miles on the tires?
 

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Meister said:
...And it's a shame that, beyond your initial disclaimers, one must even have that inner debate as to how much sensitive information to release due to valid concerns about how such information may be received and treated here.
I know EXACTLY what you're saying Slick!!

I think NR is sincerely and legitimately concerned about the safety issues... with a disclaimer about the results of doing this without advanced driving/handling skills, and doing so in the proper setting, I don't see a problem with it - we're all adults. Besides, I can't wait to read another one of those "NR write-ups" :drive:

WingEEE :wink1:
 

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Would like to see someone with a clean bias on the issue, NR, you're the right man for the job.. Let us know what you encountered when you shut off the car's brain telling you how far you can drive it..

It will also give us a good idea what to expect from GSM's latest ESP and trans shift "mod"
 

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NR, you are the one to post it with your experience...I'll be awaiting anxiously!
 

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I am definately interested in your findings. You also seem the right man for the job :biggrin: ......so without further ado...........let's have it.
 

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May as well get it out before we all pull the fuse and try it!!!! :evil:
 

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Discussion Starter · #16 ·
Ok, got the disclaimer out of the way, and it seems like there is some interest - so here goes.

When you look into the engine compartment, you will see a box by the fuse box that has all kinds of metal tubes running from it. This is the ESP / BAS control module - a smart module that co-ordinates brakes, throttle and transmission interaction, over and above driver input. The objective of this system is to allow the car to accelerate smoothly regardless of the surface; ditto for braking - and keep the car going in the intended direction (yaw control). It is capable of making rapid adjusments to brake power and torque in the blink of an eye. By default it is on. when you push the ESP button on the dash, it does not turn off - it just grants you broader movemnt before intervention. Mercedes pioneered this system and most of the time, it operates unnoticed by most drivers.

All this is controlled by fuse 17. When this fuse comes out, the entire system shuts down. The anti lock brake function is gone; traction control is gone; as is yaw control and torque modulation.Loss of these functions seriously degrades the collision avoidance ability of the car. In effect, it returns it to the technology of 30 years ago. It makes no sense to disable this system under normal street driving.

For performance driving at the drag strip, the autocross, or road circuit, turning these features might make for faster shifts; higher cornering speeds and better threshold braking.

I was supposed to do a day of advanced lapping at Mont Tremblant last Wed., but the hurricane remnants put an end to that plan. I had hoped to run a set of laps with the fuse in and with it out. The lap times would be hard data and my observations, providing I kept the rubber side down, would of added to the experiment.

This morning, I decided to pull fuse 17 and head out onto my favourite back roads for a bit of spirited driving. When my 300C started up, the ESP/BAS light came on and stayed on. Driving out to my favourite twisty 2 lane black top roads, the shifting did indeed seem very smooth. In drive, it seemed to hold gears longer. The intermittant mid range throttle hesitation was definitely gone. Unfortunately, the roads were unusually busy with Sunday drivers enjoying the nice weather. Long ,fast runs were not feasible.

My first test was braking. I used a modest 50 mph with firm pedal pressure.
The car stopped quickly and smoothly with no lock up (I'm running 255/55/18 BFG KDW2's with 35 lbs pressure). Next braking test was at 60 mph with hard pedal pressure. the car stopped straight and quick - again no lock up.

Nex test was threshold braking (used by racers to get max braking without lock up just before a corner). I did this on a straight stretch. I took the car up to 75 mph and wanted it down to 40 mph. I applied full pressure and expected to have to let up at point of lock up. The car was down to 40 mph, again with no lock up.

On to acceleration tests. Car at dead stop. Tranny in drive. Trottle quickly to WOT. Mild wheelspin in 1st; sharp shift up to 2nd - chirp in second; small chirp in third. seemed fast. Next run. Dead stop. Tranny in 1st. WOT. Same reults as in drive.

Cornering. I have a run that is a series of straights with 3 alternating 90 degree curves. Posted speed is 50 mph with 25 mph in corners. I routinely run these corners at 60 mph with the fuse in. I only got one run in. I approached the corners at 75 mph, braked to 50 mph, put on WOT after apex. Car ran smoothly. Did the 2nd and 3rd at 60 mph - no drama - except in the 3rd corner. A red dodge minivan coming in the opposite direction was over the centerline. I had to correct and move over at the last second. again the suspension tolerated this transition with no fuss.

Back home. Turned car off then back on. No error codes - just the ESP /BAS warning light on the lower right corner of the instrument panel.

Analysis? Inconclusive. Roads were dry - the tires very sticky, and g forces not high enough to put the car out of control - at least with my driving style.

The transmission definitely felt stronger. I hope we can keep this thread going - get some other results from experienced drivers; love to see some quarter mile timeslips; and some tech notes from people who understand how all of these systems work.

I still plan to go to the track. In the meantime, I strongly recommend you keep that fuse in place for everyday driving.
 

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Many of you are familiar with GM's attempt to satisfy fuel mileage/emissions requirements by utilizing the "skip shift" technology on their manual transmissions. This can easily be defeated by installing an in line plug which essentially fools the ECU thereby allowing first to second shifts under light throttle. This method does not cause a warning light on the dash.

There must be a similiar solution to our ESP situation. I suppose this is what GS is attempting to do with their kit. Personally, I would like to have the option to have a third ESP choice-turn it completely off- such as has been reported here that the Charger SRT will have.
 

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300CGuy said:
I posted in LX that I tried this and it actually slowed my times because they car wouldnt stop spinning till it got to 3rd gear.
Well, I certainly know now what I'll be doing when my conti's are ready to come off! :) :newangel:
 

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Nice write up NR!
Meister - yes sir, I have stock contis with 8,500 on them. They spun like crazy all the way to third...but with a nice set of tires that could be eliminated.
 

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Discussion Starter · #20 ·
I think my run established a few things -

the suspension and brakes on the C are awesome - put some performance tires on and it really shines, even without all the electronic "nanny" intervention. Also, the tranny felt strong in drive - no hesitation or early shifting.

Pulling the fuse is not the answer. I will be looking forward to see what GSM, Superchips, etc. come out with.
 
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