I've been agonizing over this for weeks and have scanned the threads looking for some divine guidance. It's one of those decisions that you do your best not to second guess yourself after the deed is done.
The Cruise Night season is starting up out here and I'm hoping to talk to some experienced Challenger owners to get their feedback also.
Purchased my 2015 SXT with chrome clad 18's and never really though much about 20's until I started reading the forums. Now I realize how really great the 20s look.
As many of you know, I'm looking at a minimum $2000 investment if I decide to upgrade.
My past research has helped me realize that bigger wheels won't do much to negatively affect the ride, handling or speedometer functions in my Challenger. The one issue that I keep returning to is the fact that I've not read anything at all negative about mitigating from 18s to 20s and that sounds to good to be true. I did read somewhere that the SXTs that come from the factory with 20s and A8 transmissions have different rear end gear ratios.
My last ride was a 2006 Corvette with the Z51 handling package and I can't imagine any changes I could make to my Challenger would yield a firmer ride than that.
I'm looking for a few Devil's advocates to enlighten me on any issues I should really be concerned with if I make the switch to 20s.
Any and all advice is welcomed.
Thank you,
S A E T T A
Okay, I have gone through this very thing on two different Challengers, so I think I can offer up some of the info I managed to gather together while trying to decide for myself.
(Remember, this is all worst case scenario type stuff; I'm playing Devil's advocate as you requested. Don't think I am trying to talk you out of the upgrade, just make sure you have plenty of info before doing it)
If you do go from the factory 18" wheels & tires to a 20" wheel & tire, these are the things you should try to do in order to avoid any unnecessary headaches or problems:
1) If at all possible/plausible, try to find a set of factory 20" rims to go with instead of some aftermarket el-cheapo brand you've never heard of, but they are really good price so you got them anyway. The factory 20" wheels were made to work with these cars, and manufactured with a modicum of quality standards in mind, and can be trusted to serve you well in times of extreme stress. The same cannot always be said for some of the aftermarket wheels available out there (read: Made in China).
2) Try to run the OE tire size from the factory 20" rims on your new rims (no matter what rims you decide upon). For on these cars I believe that is 245/45/20 or something similar (I could be wrong there, but it's easy to look up to verify). That will ensure that your speedo isn't thrown out of whack by the change in wheel/tire size.
(Because the factory 18" rims with 235/55/18 tires are roughly the same diameter as the factory 20" rims with their OE tires - both 27.x inches IIRC, which is all the speedo cares about).
3) If you do decide to go with an aftermarket rim instead of one of the factory 20" models, make sure to pay attention to the weight of each wheel you are considering for purchase, and buy the absolute lightest one of all the ones you like. Or at the very least, do not buy a 20" wheel that is significantly heavier than your current 18" wheels.
Not many people pay attention to this spec when shopping wheels, but it is a very important one to know if you are putting them on a base model Challenger, e.g. standard sized brakes, standard suspension, high-geared rear-end, and no-torque-having-engine.
The thing to remember is that any extra weight added to the wheel/tire combo is 4x worse than that same amount of dead weight just thrown in the trunk because it is unsprung weight that the car is going to have to get moving from a dead stop and conversly bring to a dead stop when already moving at high velocity.
In other words, 8 extra lbs. on each corner of the car means 32 extra pounds of unsprung weight the car's suspension and brakes have to deal with, and while it doesn't sound like much, it WILL make a difference. Especially when you consider the brakes, suspension, rear-gears, and engine of these base model Challengers that is having to do the extra work now.
Will the car be able to handle that extra weight at each corner, sure. Would you see negative effects over time, most likely. In the short term, you'll probably lose some MPGs, and the braking distances will also increase, though they would likely be small enough as to go unnoticed without actual measurements being performed. Also, don't forget the slower acceleration, but there again, it probably wouldn't be noticed unless a bunch of 0-60 runs were performed and timed precisely.
All of that is certainly acceptable I think though, espeically if you really like the look of the 20" rims on these cars, and I think most people agree they look better with them. If you are racing the car, then maybe those draw-backs are not going to be acceptable, but then again, if you're racing one of these base trim Challengers, you have bigger things to worry about I think.
Now if you ever decide to upgrade in the future to some 22" wheels or something, now you absolutely are going be putting more stress on a base trim Challenger's suspension, brakes, etc. Not to mention some really heavy 22" wheels and tires might start to really drag the car down in terms of acceleration and really increase the braking distances in a noticable fashion.
Any upgrade that drastic should be carefully planned in my opinion so as not to negatively affect the driving experience that the SE/SXTs has to offer.
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