Anybody know what type of rear end is in the new Charger? Are there aftermarket gears for this rear end, what ever it may be? The reason I ask is that the rear gear is only 2.82:1 and is not a very suitable ratio for getting quick performance out of a 4000lb car. The transmission ratios look great though! 1st: 3.58, 2nd: 2.19, 3rd: 1.41, 4th: 1.00, 5th: 0.83. Can anyone say "Close Ratio"?
(You don't see something other than 1:1 in 3rd very often if at all in an auto!)
This thing looks like a 3.23 rear ratio would do wonders for in town driving excitement!!!
With the relatively high numerical ratio of 5th gear Overdrive, 3.55 is about as radical as I'd probably want to go.
Take a look at the attached Excel speadsheet for RPM, MPH, and gearing.
blackarmy
06-10-2005, 01:37 AM
You know what, I dont know didly about gears. Any one care to give a quick lesson here?
'03 MOPAR R/T
06-10-2005, 02:35 AM
Well blackarmy, this may be a bit much all at once, but in my first post above I have an Excel spreadsheet that allows you to plug in different tire sizes (the outside diameter size affects how a car will run), rear gear ratios, transmission gear ratios if you so choose (its setup now to be exactly what is stock for the new charger, but if you ever wanted to do a "what if", all you'd have to do is charge to gear ratios around and see what it does). Those three small things are all you have to think about when trying to get the performance you want.
One thing to note is that for any given gear, say 2nd gear, that is really a combination of (actually a multiplication between) the rear gear and that particular transmission gear. So in the case of the stock new Charger, 2nd gear is 2.19 and the rear gear is 2.82. Multiply them together and you have the actual gear ratio that the vehicle has to rotate the rear tires with, in this case 2.19 X 2.82= 6.18. So, in second gear the tires make one revolution but the motor makes 6.18 revolutions in that same time.
To get a good feel for what that means try to envision an example taken to the extreme: What do you think that a vehicles performance would be like if the motor was to turn over less than the rear tires per turn? Say the rear tires went around 100 times for every revolution of the motor. Wouldn't it seam that the tires were going really fast for just one turn of the motor? Sound pretty impossible doesn't it. We all know that for those tires to be going that fast that the motor would have to be super powerful or something crazy to be able to get so much work done for so little effort! All that for just one turn of the motor? It doesn't work that way. In actuality, to get the tires and vehicle to move, the motor has to expend alot more effort, it has to turn over many times more than the tires do to really wind up and use its revs to get it going. So a high numerical gear ratio will give a motor more mechanical advantage and get the vehicle going quickly, but the trade off is that the motor will rev out quickly as well. That is oversimplified but is a general example.
It really comes down to the gear ratio and the mechanical advantage that that ratio provides. The higher numerical value that that ratio is, the easier it is but more quickly will rpm increase. I hope this makes sense! ;) :crazy: :huh: :WHT:
Anyway, I don't know if I've helped or hurt more but anyway take a look at the spreadsheet if you can and play with the numbers. Remember, on that spreadsheet, all you can change (and have to worry about) are the cells in green. Everything else gets calculated for you. Also, anywhere you see a small red triangle in the upper right corner of a cell, that means that cell has addition info. Just move your mouse cursor over the cell and pause there briefly and the additional info will appear.
One other thing, if you have any questions, ask away and I'll do my best (as will others I'm sure) to help redirect.
Also, sorry for the confusion but the excel file in my first post has ONE small error. I can't edit it so I'm attaching a new updated file here.
'03 MOPAR R/T
06-30-2005, 09:21 PM
TTT, anyone have any info on what model of rear end housing is used in the new Charger? What size, how strong, different gears available?
I would think that once the Charger has established itself and the number of owners have increased that this is going to become a big issue. If anyone has been following the HEATED debate on the 3rd gen. Ram's stock gearing inefficiencies, then you will probably make the same conclusion about the Chargers gearing, stock has it's flaws, DONT FEAR THE GEAR!
I believe that the Charger in it's stock form would do wonders with a rear gear swap to lower (higher numerical) gears. Heaving a 4000 lb. car around will be alot easier in any gear if the stock 2.82 rear gears are swapped for a more performance oriented ratio. With overdrive trans. these days, it's a no-brainer because you still retain highway speeds at a reasonable rpm.
Somebody take a look at this, I would think that others would agree!
Edit: With the trend of bigger wheels and tires comes lower overall gearing in most cases so that alone could be reason enough to start looking at gearing. Again, with overdrive transmissions there is NO reason not to have steep gears! :drivingz: :drivingz: :drivingz: :rck: :D
Hercules
07-01-2005, 09:59 PM
I believe the SRT versions use a 3.07 rear ratio....and I believe its the same rear, just a lower gear...and another 75hp or so.
DAYTONA_R/T
07-01-2005, 11:17 PM
TTT, anyone have any info on what model of rear end housing is used in the new Charger? What size, how strong, different gears available?
I would think that once the Charger has established itself and the number of owners have increased that this is going to become a big issue. If anyone has been following the HEATED debate on the 3rd gen. Ram's stock gearing inefficiencies, then you will probably make the same conclusion about the Chargers gearing, stock has it's flaws, DONT FEAR THE GEAR!
I believe that the Charger in it's stock form would do wonders with a rear gear swap to lower (higher numerical) gears. Heaving a 4000 lb. car around will be alot easier in any gear if the stock 2.82 rear gears are swapped for a more performance oriented ratio. With overdrive trans. these days, it's a no-brainer because you still retain highway speeds at a reasonable rpm.
Somebody take a look at this, I would think that others would agree!
Edit: With the trend of bigger wheels and tires comes lower overall gearing in most cases so that alone could be reason enough to start looking at gearing. Again, with overdrive transmissions there is NO reason not to have steep gears! :drivingz: :drivingz: :drivingz: :rck: :D
with trucks, putting oversided tires on it is a reason for re-gearing... but if the overall diameter of the tire is same as stock, you are not changing the overall gear ratio of the car.... I see you have a stratus and a rumble be... and guessing you are looking at this from a truck person point of view (I am a truck person myself so....)so the wheel/tire thing has no bearing with this car... (unless you plan to lift it and put 33's or 35's under it) ;)
Anyway... if you are wanting to get better performance, and dont care about loosing a few MPG then a gear swap suits... but for those that have this as a DD and do alot of driving, you will be happy with the performance of the R/T in stock form, without giving up more fuel economy then needed....
I am getting my daytona as a fun DD..... not to go to the track every weekend.... so stock is fine for me....
v10sport
07-02-2005, 12:00 AM
Doesnt the 300 use a dana 44 center section?
Good chance the charger will be the same
'03 MOPAR R/T
07-02-2005, 01:45 AM
[QUOTE=DAYTONA_R/T]and guessing you are looking at this from a truck person point of view (I am a truck person myself so....)so the wheel/tire thing has no bearing with this car... (unless you plan to lift it and put 33's or 35's under it) ;)QUOTE]
Well, I don't want to sound like I'm arguing but I definitely am NOT thinking from a "truck" point of view, just simple performance math and relationships.
Regardless of tire size,(as long as it's not UNDER sized vs stock) stock or larger the 2.82 rear gear is a pretty darn high gear ratio. IF you change out to 20" wheels and tires there is a fair chance that the overall dia. of the tires will increase and make the gearing even higher. This has nothing to do with trucks and 33"-35"-80"-1000" tires. I shouldn't have even brought up the subject of tires and wheels, I should have just talked about stock. The stock R/T 225/60R18 tires are 28"-28.6" in diameter. How many 20" tires do you know of in that size?
As I say again, even in stock form the 2.82 stock rear gearing is rather high geared, a steeper gear IMHO would get this relatively heavy car going with more punch.
I love the new Charger and hope to get one in a few years (if not sooner :D ) but when I don't have something it drives me crazy so I engulf myself in research and planning and thoughts about the vehicle and modifications I'd like to do to it. This is something that has caught my eye and has raised my eyebrow towards the possibility of better acceleration and performance with this vehicle with a rear gear change as opposed to stock.
On a side note, in my Rumble Bee I've noticed that around town driving between 45-60 mph if you get on it with mid throttle acceleration (not loafing but not WOT either) it will bog out. Cars these days are across the board geared too high in my opinion. I don't want to bog myself to a belly up submissive death but rather when I move the throttle pedal I want results!
Also, the kickdown is not the answer. I don't want to wait 2 seconds for the computer to hold a special session or committee meeting to decide on what gear to put me in before I actually get going when I mash the throttle. I want acceleration in the gear I'm in and I want it now! That is what I absolutely LOVE about my Stratus, the Autostick. I know it's still an automatic, but it DOES give you control over your car and its driving characteristics. If you punch it in gear and you bog out, well it's up to you to down shift to get the gearing and rpms working for you. If you don't want to you don't have to, it'll let you do what YOU WANT TO DO, not what it thinks is best for you. That is my BIGGEST pet peave with new cars these days is the lack of CHOICES! All of these electronic wonders and features like torque management for example have their place and are useful, but, they are not the end all answer to all driving situations. If you could just have an on/off toggle of the features that would be the ultimate solution. If you want them great leave them on, if not, GIVE ME THE ABILITY TO CHOOSE NO!
.....anybody still with me? I think I'll ease backward offstage, never breaking eye contact until just the instant before I turn and dash behind the curtains now..... :D :D :D
Sorry for the rant, it is something that frustrates be though.
chargin06
07-07-2005, 02:46 PM
I like that spreadsheet!
Thanks!
maneval69
07-07-2005, 03:40 PM
There are no after market rear gears available for the RWD LX Hemis. And no one has been able to determine if the SRT8 gear will interchange mechanically. We are sure you can change the whole rear assembly out of a SRT8. Then you have to deal with calibrating the ESP system and speedometer.
One would think that for something to be made available there would have to be kit that took care of all those problems and would probable have an LSD unit included. And you would be talking about $2K or more.
As far as gears go, the Charger has a lower 1st gear than the GTO with the Manual trans.
The LX 5 speed 1st =3.59, 2nd =2.19, 3rd = 1.41, 4th = 1-1, 5th =0.83. (rear gear 2.82)
The tremec gear ratios are 1st=2.92, 2nd=2.07, 3rd=1.43, 4th=1 (rear gear 3.42)
So here is a comparison between the GTO and Charger final drive ratios in each gear
1st GTO= 9.98, Charger=10.12
2nd GTO= 7.08, Charger= 6.18
3rd GTO= 4.89, Charger= 3.98
Don’t get me wrong, I would love to have the 3.06 gear out of an srt8 or even wilder about a 3.23 gear. A lot of people on the magnum site talk about 3.90 or 4.10 gears but if you go that high you are making first gear useless.
But I just wanted to show that the 2.82 rear gears are not as much of a disadvantage as it would seem.
here is a thread that has some good info and links
http://www.lxforums.com/board/showthread.php?t=14248&highlight=rear+gears
'03 MOPAR R/T
07-07-2005, 06:30 PM
I like that spreadsheet!
Thanks!
No problem, my pleasure! :)
I made that to try and help people understand (and use as a tool) how changing drivetrain math with change the vehicles performance. It seems as though many don't understand how the relationships that these FEW different parameters change the vehicles driving characteristics.
Play with the MATH and DON'T FEAR THE GEAR! (with OD trannys that is! :D )
'03 MOPAR R/T
07-07-2005, 06:49 PM
So here is a comparison between the GTO and Charger final drive ratios in each gear
1st GTO= 9.98, Charger=10.12
2nd GTO= 7.08, Charger= 6.18
3rd GTO= 4.89, Charger= 3.98
...But I just wanted to show that the 2.82 rear gears are not as much of a disadvantage as it would seem.
Well, 1st gear may be better than the GTO but 2nd and 3rd are lacking. 1st is usually over so quick that I would rather have a better pull where I'm going to be spending MOST of my time, in 2nd and 3rd.
Regardless what you compare the Charger to though that is not my main concern, I don't waste my time comparing the Charger to ANYTHING anyway because it is in a class of its own! With that said, I am talking specifically about the gearing of the Charger as it relates TO the Charger and ITS OWN performance. 10.12 in first is not going to get my heart pounding and my adrenaline going, it's still too high geared for my tastes. I'd prefer to see about a 12.5 to 1 in 1st! :D, especially with the weight of the Charger.
The W5a580 transmission would be the ULTIMATE tranny if it only had a .70 overdrive ratio in 5th!!! Damn Chrysler for keeping it low geared in OD, it ALMOST ruins the great 1st gear ratio uniqueness and performance benefits! :VHOT: :mad: :VHOT: :mad:
GTO SCHMEETEOO!, you have to keep on track with the weight of the CHARGER and future mods to even further slow it down like larger dia. tires and possably heavier unsprung mass (wheels + tires).
If I gave a crap at all about anything from Socialist Australia I'd drink Foster's Piss Lager!
:thatfunny :thatfunny :thatfunny :thatfunny
maneval69
07-07-2005, 08:59 PM
Sorry about you paranoia but I was not comparing the Charger to the GTO. I was using the GTO as reference to final drive ratios and why ours is not as bad as one would think. I could have easily used the Viper, Camaro, or Mustang. Pick one that doesn’t offend you and move on to the POINT.
As to the Point of gearing,
You have a good point about having the mechanical advantage in the gears you spend more time in. But that’s that what selecting gears is about.
If your gears ratio is to low, then you're engine doesn't get to it's power band as soon and doesn't stay there.
If you’re gears are too high, then you don't take advantage of your best mechanical advantage. Countering the effects of the mechanical advantage gained in second is shifting one additional time at the worst time. Each shift is lost acceleration time. You accelerate quicker at the beginning of the ¼ than at the end. There for the earlier you shift the more time the shift cost you. (Not spending enough time in the gear with the greatest acceleration)
The reason there is such a big step in from 1st to second is to get the engine up in its power band quicker. Once you shift in to second the gears are spread to keep you in the power band. That’s why the SRT8 get a higher ratio gear.
Here are the speeds at shift points for the RT and SRT8
From those numbers I would think 3.06 would be best for the Charger R/T. 3.42 and you would be in the middle of a shift at the end of the ¼, and 3.73 would put you at the beginning of the next gear and adds an extra shift but not enough time in the gear to make up for the shift time. 3.92 would be great for the ¼ if you could make up for the two shifts below 60MPH. You probable will but it would suck driving on the highway at 80.
Now you add power, raise the shift points and all that changes.
By the way I think Fosters sucks also.
'03 MOPAR R/T
07-07-2005, 11:41 PM
Well, I should probably get this out of the way since I'm fairly new here and haven't established my personality yet, good or bad.
This isn't in defense or offense, just cheeky if anything. I make wild accusations and tell tall fish stories but I am NEVER as one sided as I make myself out to be. I'm just trying to get at a point with a bit of melodrama thrown in for humor.
The internet can be pretty hard to communicate at times, there is no body language or voice inflection to hint at the true meaning of what you are saying....
Hey, It's all good.
I figured there was some jest in your post. It makes the post fun to read and fun to respond to. Especially when brand loyalty comes in play.
Anyway, I hope that the SRT-8 gears are direct bolt ins. We all agree that all things being equal, the higher the ratio the more fun the car is to drive. Throw LSD in and the LX cars would be a ball.
'03 MOPAR R/T
07-08-2005, 11:29 AM
Well, just look at it this way, it's just one more motivating factor to pony up to the SRT-8, we all know that's what we REALLY want anyway, right!? :D
