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Discussion Starter #1 (Edited)
I'll put some more data into this post tonight (when not taking a quick lunch at work) but I think one of the most useful threads here could be simply sharing your setup (wheels, tires, alignment, springs, etc.) and what you think about it.

My short setup description:
  • 10" front wheels with 15mm offset
  • 11" rear wheels with 21mm offset
  • Tires - 295/35 Pirelli Corsa R compound tires from Tire Rack
  • Mopar Springs - nothing fancy here
  • Speedlogix front brace
  • Petty rear brace with x crossover
  • Razors Edge subframe connectors
  • Brake pads - Hawk DTC60
With just these changes the car can hold its own on a fast road course

For this season (no track time yet)

  • 10.5" front wheels with 10mm offset
  • 11" rear wheels with 20mm offset
  • Toyo R888R 305/35/20 tires from Tire Rack
  • Downforce Solutions wicker bill rear spoiler
  • Downforce Solutions splitter & canards
  • Speedlogix harness bar
  • ZL1 Addons tow hook on front (still need to drill hole for rear mounting)
  • BWoody 3" LTR heat exchanger
  • LMI Intake
Even though the car is lowered I like my alignment specs. No need yet to get any adjustable parts for that.
 

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Any of you tried the Speedlogix billet trailing arms? I'm considering some.
 

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Challenger SRT Redeye
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Great, we have a section! Nice set-up TD. I'll post in the MN thread, but I am going to the car show on Sunday. Looks like rain Saturday, mine will melt. Hope to see you and your car Sunday.

Anyway, suspension, here goes...

My car has its entire interior intact.
Engine - only mod - catch can
Fuel = 93 octane with Torco Booster
For brakes and some weight savings
Demon Performance Brakes X4
Road course pads -Hawk DTC-70 X4 On my shelf DTC 70 F // DTC 60 R
Driveshaft - QA1
Half shafts - DSS with custom blueprint/mod to CV's with special boots
KW adjustable springs X4 - lowered center of gravity and progressive rate
Rear suspension
Razors Edge Trailing arm
Razors Edge top and rear adjustable control arms
Polyurethane cradle bushings
Speedlogix sway bar connector - short not adjustable
Front suspension
Razors Edge strut connector
Screw the adjustable sway bar connectors, they are on my bench, they
make way too much noise (click LOUD).

Track = OEM wheels with Michelin PS4S 285/35 X4
Street =Triumph Performance Wheels and PS4S tires 9.5" F 285/35 10.5" R 295/35

I am with Trackday, my alignment works pretty well. I may tweak the back because I can see a wear pattern on the rear to suggest I need MORE negative camber.
 

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Discussion Starter #6
Any of you tried the Speedlogix billet trailing arms? I'm considering some.
My opinion is we really don't need to spend money on suspension components in the beginning stages, especially not at road course speeds. These cars are really all about wheels and tires.
The stock brakes do really well on tighter road courses but once you're hitting 130 mph or above the DTC60 and DTC70 pads are a good choice.
The springs are more of an appearance mod I think, with a little bit of negative camber capability added in.
 

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I would seriously like to add some 10" wheels on the front with 295's and keep the 305's on the rear, I would likely need some Lil' Devil fender flares though.
 

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I’ll need to disagree about the springs and lowering. Lowering the center of gravity of these heavy rigs does help. My lap times improved with the lower car and definitely notice the progressive spring rate helps hold the car from a deeper lean.
 

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I would seriously like to add some 10" wheels on the front with 295's and keep the 305's on the rear, I would likely need some Lil' Devil fender flares though.
Those do look ok. Seems like a good thing as opposed to allowing rubber to extend out.
 

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Discussion Starter #10
I would seriously like to add some 10" wheels on the front with 295's and keep the 305's on the rear, I would likely need some Lil' Devil fender flares though.
No flares needed. This is my car with that setup. It's worked well for over a year.
View attachment 454905
 

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Discussion Starter #12
I’ll need to disagree about the springs and lowering. Lowering the center of gravity of these heavy rigs does help. My lap times improved with the lower car and definitely notice the progressive spring rate helps hold the car from a deeper lean.
What I'm looking for is a linear spring rate instead of progressive. Progressive is nice for little stutter bumps on the street but it's really not the right choice for a track. I would have the KWs if they just offered a selection of spring rates. I had some Ground Control coilovers for my 94 Firebird and had a near infinite selection of springs available. I got my shocks revalved too. That market just has never come to Challengers for anything close to affordable to me.
 

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What I'm looking for is a linear spring rate instead of progressive. Progressive is nice for little stutter bumps on the street but it's really not the right choice for a track. I would have the KWs if they just offered a selection of spring rates. I had some Ground Control coilovers for my 94 Firebird and had a near infinite selection of springs available. I got my shocks revalved too. That market just has never come to Challengers for anything close to affordable to me.
We will agree to disagree. I have them on a ‘15 Hellcat. It rides great on the street. When challenged on the track the more “stiff” competition spring rate happens and improves the rebound and is more stiff. I paid for the KW’s and my testimony is that they improved my times and made my car better for the track.
 

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Discussion Starter #15
We will agree to disagree. I have them on a ‘15 Hellcat. It rides great on the street. When challenged on the track the more “stiff” competition spring rate happens and improves the rebound and is more stiff. I paid for the KW’s and my testimony is that they improved my times and made my car better for the track.
I think we've learned over the past couple of years that we disagree a lot. ;) I'm not sure we have any of the same parts on our car except maybe the front shock tower brace. It just shows there are many ways to accomplish a goal. We both go out there and have fun with cars that are thought to be much faster than ours and we both have a lot of fun. I'm good with that.
I'll stand by my statement though, that wheels and tires are the change for this car. Since the best tires are significantly lower profile, some lowering springs help a lot with the appearance factor and the springs give some natural negative camber without buying any adjustable parts. Some people have seen alignment specs with lowering springs they don't like and as a result have still bought the adjustable suspension components to get back the alignment they want.
 

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NT05s in stock size mounted on sperate set of rims
ZL1 tow hooks front and rear
Speedlogix strut tower brace front and their 4point in rear

The absolute mod ever? LOTS of seat time. I’ve gone to at least 1 track event per month for the last year. And good portion of those events are multi day events.
 

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For everyone considering lowering there is a big caution. I know we have posted about it, but let’s get it in our new thread. With lowering comes the risk of exposing a weak link. The half shaft axle boots.

Seems if you are in a course with say max speeds below 130 mph little or no problem. But as your top speeds and then more heat and more high speed centrifugal force work together the boots on the OEM shafts AND both the DSS and GForce shafts will get soft and begin to fail.

Be aware of this because if you ignore it you will eventually have a CV failure. The first signs of boot failure will be grease appearing inside the barrel of the rear wheels.

I believe the half shafts I modified may be he solution, but until I test them on June 11 at what is the worst offending track (BIR Donnybrook) I cannot say it is solved. Give me a couple of weeks and I will of course report back.
 

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Discussion Starter #19
For everyone considering lowering there is a big caution. I know we have posted about it, but let’s get it in our new thread. With lowering comes the risk of exposing a weak link. The half shaft axle boots.

Seems if you are in a course with say max speeds below 130 mph little or no problem. But as your top speeds and then more heat and more high speed centrifugal force work together the boots on the OEM shafts AND both the DSS and GForce shafts will get soft and begin to fail.

Be aware of this because if you ignore it you will eventually have a CV failure. The first signs of boot failure will be grease appearing inside the barrel of the rear wheels.

I believe the half shafts I modified may be he solution, but until I test them on June 11 at what is the worst offending track (BIR Donnybrook) I cannot say it is solved. Give me a couple of weeks and I will of course report back.
My stock axles lasted only about 10 laps at BIR. They had done multiple track days at Waterford Hills, Nelson Ledges, M1 and a lot of autox events without issue. You can see the white smoke in my rear view mirror in my BIR video around lap 8, just at the end of the video. It was VERY noticeable and made the Viper behind me veer quickly to the side thinking he was going to hit an oil slick.
I may still be able to make it out there with you on June 11 but I won't know until later next week. If I make it out there, I'll be testing the Demon axles at MP lowering spring rear ride height. So, effectively we'll find out if a stock WB with MP springs might have an issue as well.
 

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Great thread guys. I've found the KW's adjustable with the lower center of gravity really do a great job a great job in the corners, But tires is the #1 big change. Pilot Super Sport 4s are great track tires for hot tracks and in the rain. Next to R compound these are the best.
 
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