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Discussion Starter · #1 ·
I know, I know, there are lots of post that might answer my question(s) below but I'm hoping to get information a little less than 2 years old.

I plan to set my Redeye up for road course fun and maybe competition at some point when I can finally catch up to the capabilities of the car. I reached out to a professional driver who recommended a few things such as wider/stickier tires, track specific brake pads and brake fluid. Also on the list is replacing the factory Brembo's with Viper ACR-E brake caliper's and also lowering the car a bit with an emphasis on a softer front and stiffer rear springs. He did not recommend a manufacturer of lowering springs so I've been on a search. I've got a full AAD suspension kit ready to bolt on but want to get springs so I can do the work at the same time. The AAD kit will allow me to adjust/correct the camber and toe to street and/or track depending on what is needed.

In my search for springs I've been trying to find the 2019 Redeye factory spring rates so I can make sure the replacement set is an improvement in my desired direction. I've heard the OEM Scat Pack springs might be close to what I'm looking for in spring rate but won't lower the car. The Mopar Perf lowering springs might lower the car but if I'm not mistaken won't do what I need in spring rate.

Any help would be greatly appreciated.
 

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I'm curious: what problem(s) are you trying to fix? Since you've already stated that you need to "catch up" to what the car can do, I suggest leaving it alone until you can point to a specific performance aspect that isn't working (i.e. mid-corner understeer, brake fade at the end of a stint, outer shoulders too hot, excessive nose lift/dive, etc.) and fix them surgically.
 
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Discussion Starter · #3 ·
I'm curious: what problem(s) are you trying to fix? Since you've already stated that you need to "catch up" to what the car can do, I suggest leaving it alone until you can point to a specific performance aspect that isn't working (i.e. mid-corner understeer, brake fade at the end of a stint, outer shoulders too hot, excessive nose lift/dive, etc.) and fix them surgically.
Springs: The change of spring rate will help with inherent understeer with the car due to its weight. Brakes: The car was not designed to be tracked for extended periods so it needs help in the brake department, i.e., pads, fluid, calipers and rotors. The OEM brake system will be what prevents me from spending more time on the track because of brake fade and boiling fluid.

Keep in mind, I didn't come up with the data in my original post. I have done lots of research but with very limited track experience so I reached out to a professional. I got this from a racing professional who has year's of seat time in the Redeye pushing it to its limits.
 

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The problem is what might work for the professional may not work for you. hklvet brings up a good point.

Leave the car stock and get some track time experience with the car. I dare say one can benefit from track driving lessons than he can from any car mods.

As you gain seat time the car's shortcomings will become apparent. You will also get exposed to a number of other participants driving Redeyes and you can possibly learn from them what they fund what helps what doesn't. I mean you have the input of one racer but it would comforting I think to see others doing the same thing. Mods cost considerably money and you want some confidence the mods are the right mods.


So initially leave the car stock.

I'd be sure to show up with fresh oil in the engine, fresh brake fluid, and plenty of material on the pads and plenty of iron on the rotors and plenty of rubber on the tires.

Initially the brakes will get hot and you will need to bring the track session to a close to give the car time to cool down. Be sure you take a cool down lap before pitting.

Not sure what one can do with the brakes. Larger brakes will give one more braking power but still they'll get plenty hot. One might consider instead of trying to throw some magical pads or super duper rotors on the car to figure out a way to route cooling air to the existing brakes. While this may not be as "sexy" as exotic brake pads, bigger brakes, better cooling means better cooling no matter what brake hardware you end up running.

My info is when changing springs ideally the shocks need to be changed. With lowering springs the spring rate changes and the stock shocks may not be up to the task of dealing with this. You can still change springs if you believe different springs are called for but you need to consider a spring/shock package with the shocks matched up to the springs.
 

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Discussion Starter · #5 ·
The problem is what might work for the professional may not work for you. hklvet brings up a good point.

Leave the car stock and get some track time experience with the car. I dare say one can benefit from track driving lessons than he can from any car mods.

As you gain seat time the car's shortcomings will become apparent. You will also get exposed to a number of other participants driving Redeyes and you can possibly learn from them what they fund what helps what doesn't. I mean you have the input of one racer but it would comforting I think to see others doing the same thing. Mods cost considerably money and you want some confidence the mods are the right mods.


So initially leave the car stock.

I'd be sure to show up with fresh oil in the engine, fresh brake fluid, and plenty of material on the pads and plenty of iron on the rotors and plenty of rubber on the tires.

Initially the brakes will get hot and you will need to bring the track session to a close to give the car time to cool down. Be sure you take a cool down lap before pitting.

Not sure what one can do with the brakes. Larger brakes will give one more braking power but still they'll get plenty hot. One might consider instead of trying to throw some magical pads or super duper rotors on the car to figure out a way to route cooling air to the existing brakes. While this may not be as "sexy" as exotic brake pads, bigger brakes, better cooling means better cooling no matter what brake hardware you end up running.

My info is when changing springs ideally the shocks need to be changed. With lowering springs the spring rate changes and the stock shocks may not be up to the task of dealing with this. You can still change springs if you believe different springs are called for but you need to consider a spring/shock package with the shocks matched up to the springs.
Great information which seems to be the consensus, do not change anything on the car until I get some track time. That is my plan. The first couple improvements I'll be adding before I get to the track are a harness bar with harness(s) and front and rear strut bars. In my experience any bracing for a unibody vehicle is a major improvement to handling. And, they are pretty cheap items for what they offer in stiffening the chassis.

I've got the AAD full control arm kit on the shelf for a future install. Your suggestion to do springs and shocks together is a perfect idea. I'm currently looking at the Wesley Bilstein shocks when they become available. I'm trying to pair them with the right springs. They too will be a future install being aware I will be losing the ADCM.
 

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"Maybe" change fluid, only if you need it. Road America has 3 almost 3/4 mile straights, and I've never boiled fluid yet. Remember, these cars are designed for this, so you may be putting too much thought in it. Those recs sound like they're from an old-timer who has no experience as to what newer cars have now. You will be wasting money on everything brake related, except the fluid maybe. I hammered my Scat Pack last summer at the Autobahn, which is a short track. My 4-piston Brembos never faded, or lost a bit of braking ability, and they were worked hard on 4600# of weight. Like was said, find out if there are any weak points, and address them. Forget about springs too until you drive it. You'll never be able to keep up with an M3, on a small track, with a 4500#? car. Weight is murder. :)
 

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Concerning the harness bar, we have another option. As long as there isn't spinal compression in a collision, anything goes. I mounted the lap belts to the rear seat mounting bolts (longer ones needed), and the shoulder belts to the rear deck latch point. As long as there is a spreader plate underneath, we're ok. I just run the belts over the top of the seat, and wala!
 

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TrackDay, DGatzby and Sad are some fellow track day addicts that have many useful posts (including within the past two years). The AAD arms are top notch and will really help your alignment shop dial it in to handle optimally and save wear on the tires.

I don't have a Hellcat so my knowledge is limited but I recall MP (Mopar Performance) lowering springs will work/last if paired with Demon axles (which is shared by the Redeye). KW has adjustable springs but they're more than double the price of MP springs.

I'm not sure if the adaptive suspension guys even have a need for coilovers, but top tier options with height/rebound/compression adjustability, spring swappability, and true rearvcoilovers would be the Ridetech TQ and Ultimate Performance. The former has Fox shocks and the latter JRi, and both utilize US-made Hyperco springs. The only better springs you could swap in would be Swift or Draco. Wesley Motorsports, in partnership with Bilstein, is supposed to eventually come out with a fully adjustable true coilover set too.

The poor man's brake upgrade is always a good place to start in upgrading the brake system to withstand track use temps - fluid, pads and stainless steel braided lines (Goodridge is a source for that). Fluid should be Dot4 with boiling point minimums of 600F dry (new/unused) and 400F wet (old/used) like those from Castrol, Wilwood, Motul, AP Racing, ATE, Endless & Torque. Swap on dedicated race pads for track days (and sometimes rotors so you don't have to burnish/re-bed them) such as Carbotech XP10, Hawk DTC70, Raybestos ST-44 or other options from PFC, Cobalt, Porterfield, Pagid, Ferodo, Project Mu...

The Viper 6-piston caliper upgrade is an option down the line for the fronts and available from Wesley as a complete kit. The titanium pistons have a slight edge in lower thermal conductivity over stainless steel (like standard Wilwood calipers have) and much better than stock carbon steel or aluminum. Like other premium caliper options, the pistons are of different sizes too (larger ones towards the backside of rotation) in order to help prevent pad taper.

Good luck out there and have a blast!
 

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Discussion Starter · #9 ·
TrackDay, DGatzby and Sad are some fellow track day addicts that have many useful posts (including within the past two years). The AAD arms are top notch and will really help your alignment shop dial it in to handle optimally and save wear on the tires.

I don't have a Hellcat so my knowledge is limited but I recall MP (Mopar Performance) lowering springs will work/last if paired with Demon axles (which is shared by the Redeye). KW has adjustable springs but they're more than double the price of MP springs.

I'm not sure if the adaptive suspension guys even have a need for coilovers, but top tier options with height/rebound/compression adjustability, spring swappability, and true rearvcoilovers would be the Ridetech TQ and Ultimate Performance. The former has Fox shocks and the latter JRi, and both utilize US-made Hyperco springs. The only better springs you could swap in would be Swift or Draco. Wesley Motorsports, in partnership with Bilstein, is supposed to eventually come out with a fully adjustable true coilover set too.

The poor man's brake upgrade is always a good place to start in upgrading the brake system to withstand track use temps - fluid, pads and stainless steel braided lines (Goodridge is a source for that). Fluid should be Dot4 with boiling point minimums of 600F dry (new/unused) and 400F wet (old/used) like those from Castrol, Wilwood, Motul, AP Racing, ATE, Endless & Torque. Swap on dedicated race pads for track days (and sometimes rotors so you don't have to burnish/re-bed them) such as Carbotech XP10, Hawk DTC70, Raybestos ST-44 or other options from PFC, Cobalt, Porterfield, Pagid, Ferodo, Project Mu...

The Viper 6-piston caliper upgrade is an option down the line for the fronts and available from Wesley as a complete kit. The titanium pistons have a slight edge in lower thermal conductivity over stainless steel (like standard Wilwood calipers have) and much better than stock carbon steel or aluminum. Like other premium caliper options, the pistons are of different sizes too (larger ones towards the backside of rotation) in order to help prevent pad taper.

Good luck out there and have a blast!
WHOA :oops: Lots of great information here. Thank you much. Time to get to work.
 

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@Rloosarow , based on your initial post I can tall you talked to Kevin Wesley. He's a good reference, but I've had my car for 5 years and it's taken time to come to the conclusion it was worth it to me to get the ACR calipers. I punish my brakes hard at any other track than Road America and have no durability or stopping issues after just installing Hawk DTC70 pads front and rear and using either Castrol SRF or Endless brake fluid. I can kill the brakes in 3 laps at Road America since there are 3 long straights of about 150 MPH that each enter 90 deg. turns per lap. The ACR calipers won't help much with that aspect. I just need better cooling and/or DTC80 front pads to handle higher temperatures. However, the ACR calipers have tapered pistons that will help me with pad wear rate. It should make it more even so I won't have to flip the pads to get through a track day there. Again, other than Road America, I've been to Brainerd, Waterford Hills, M1 and Nelson Ledges with the car and had 0 issues. Heck, until I ran Brainerd and the 160 MPH straight with some high speed stops each lap, I was even using my stock brake pads front and rear.
Regarding springs, I'd keep what you have for now. I think there might be some advantage to using the KW springs on the front only as they are stiffer than stock, but the stock rear springs are still one of the best I think. Anything else at least starts out at a significantly lower spring rate than stock and may eventually get stiffer with compression. What noone has ever measured is how much afftermarket springs change their spring rate with compression.
The AAD suspension parts are first class but I still haven't spent the money on them. I have close to -2 deg. front camber with my MP springs and my rear is a little over -1. I get good tire wear so the cost of firmer bushings, adjustability, etc. isn't worth it to me yet.
I have the Speedlogix front brace that is triangulated (I caution against current Speedlogix products due to a lot of quality issues), the Petty rear and some SFCs with the Demon harness bar as well. The car feels very planted. I don't think any of these are necessary until you get a little time on the track with the car. They won't hurt for sure, but they're not a direct effect on lap times. They just help the car to feel more consistent and linear lap after lap on the track, at least IMO.
I missed whether you have a WB or a NB car, but get a few track days on your stock tires and then you'll likely want to get something better like a Michelin PS4 or the Continental Extremes. For a 9.5" wheel a 285/35 tire is a great next step from stock, but it's a little shorter so many people don't like the wheel gap. For the 11" wheel I'd stick with 305/35 in the same 2 brands. If you get the itch to do more, wider wheels and tires are the best equalizer we have for our heavy beasts.
 

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Discussion Starter · #11 ·
@TrackDay It was Kevin Wesley I spoke to. I am very grateful for him taking the time to offer some professional advice but I think the replies to this post has woke me up to the reality that there is a car I want and dream of in my head, then I open my eyes and realize I'm just a man with asperations but lots of work in order to get there. Your response tells me we are very like minded when it comes to what we want out of the car. But, you have the track experience I haven't gotten yet which puts us far apart. Your response, along with the others, is exactly what I was looking for. I needed to hear what modifications you have done, noticeable or not noticeable improvements on the track. How much if any loss in street comfort, etc...

Crawl before I walk, walk before I run. Get some track time in her stock form so I can get a sense of where she and I are at. Unfortunately for me there aren't very many track options in my neck of the woods, New Mexico. Sandia Motorsports Park is where I'll be cutting my teeth for now. At some point I'll make trips to better tracks when time and money permit.

Were any alignment adjustments needed after the install of the MP springs? I really would like to get the springs on sooner than later for both the handling improvement and also aesthetics. The springs are a pretty cheap mod and can be reversed pretty easily if in the future I choose a better option or I don't like the ride or look.

As far as tires go I don't see having any other choice but to buy a set of track wheels and mount track tires on them. This might be further down the road when I get a sense for how much track time I can actually get.

BTW, I have a widebody RE with PS4's at about 50% tread. Too much fun to be had. OEM tires lasted me about 4K miles. I'm at 9K on this set so I'm getting better(ish).
 

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Unfortunately for me there aren't very many track options in my neck of the woods, New Mexico. Sandia Motorsports Park is where I'll be cutting my teeth for now. At some point I'll make trips to better tracks when time and money permit.
At least you have one road course nearby! Nature of the beast unfortunately.

I have PittRace 45 minutes away and Nelson Ledges another hour beyond that. If I'm willing to drive up to 8 hours away 20 more tracks become available (VIR, Watkins Glen, Lime Rock). If I go up to 12 hours it opens up 25 more tracks (Charlotte roval, Road Atlanta, Road America).

I know there are some amazing tracks around you in TX, AZ, CO, UT, NV and especially SoCal. Hopefully, you can get to some eventually! I myself am knocking Mid-Ohio and Pocono off my track bucket list this year, then the multiple tracks at Summit Point and NJMP next year.
 
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"Maybe" change fluid, only if you need it. Road America has 3 almost 3/4 mile straights, and I've never boiled fluid yet. Remember, these cars are designed for this, so you may be putting too much thought in it. Those recs sound like they're from an old-timer who has no experience as to what newer cars have now. You will be wasting money on everything brake related, except the fluid maybe. I hammered my Scat Pack last summer at the Autobahn, which is a short track. My 4-piston Brembos never faded, or lost a bit of braking ability, and they were worked hard on 4600# of weight. Like was said, find out if there are any weak points, and address them. Forget about springs too until you drive it. You'll never be able to keep up with an M3, on a small track, with a 4500#? car. Weight is murder. :)
I would not switch to a super exotic fluid. But using DOT 4 fluid might be a good idea.

In the Drive Modes supplement under the section Guidelines for Track Use, Dodge has this:

Use of DOT 4 brake fluid is suggested for extended track usage due to increased thermal capacity.

Whatever brake fluid used it is imperative the fluid be fresh. And in the same supplement and section Dodge has this:

At the conclusion of each track event, it is recommended that a brake bleed procedure is performed to maintain the pedal feel and stopping capability of your Brembo High Performance brake system.
 

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Another thing you need to think about is beefing up the engine oil system.

Other than safety equipment, the only modification I'd make at least initially to the car, and the engine specifically, is to install a larger capacity oil pan with proper baffling and a suitable oil pickup tube to help ensure the engine always receives a good supply of oil.

Even on the dyno some OHV engines manifest a loss of power at near red line and this has been traced to the oil at high RPMs becoming aerated and this results in a partial collapse of the zero lash adjusters. This compromises valve lift and timing.

On a track not only does the engine experience high RPMs but high g-forces which can result in a compromised supply of oil to the engine.
 

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If you can't keep the oil temps below 280F maybe just ease up and only go at it 7/10ths. I wouldn't be to worried right now as you get into HPDE and have fun learning everything.

If you get more serious down the line and stuck with your Mopar, perhaps then look into cooling and increased capacity with larger remote oil filter, auxiliary oil coolers, fan for the aux cooler, oil pan w/ kickouts & trapdoors, oil accumulator, et cetera.
 
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@TrackDay It was Kevin Wesley I spoke to. I am very grateful for him taking the time to offer some professional advice but I think the replies to this post has woke me up to the reality that there is a car I want and dream of in my head, then I open my eyes and realize I'm just a man with asperations but lots of work in order to get there. Your response tells me we are very like minded when it comes to what we want out of the car. But, you have the track experience I haven't gotten yet which puts us far apart. Your response, along with the others, is exactly what I was looking for. I needed to hear what modifications you have done, noticeable or not noticeable improvements on the track. How much if any loss in street comfort, etc...

Crawl before I walk, walk before I run. Get some track time in her stock form so I can get a sense of where she and I are at. Unfortunately for me there aren't very many track options in my neck of the woods, New Mexico. Sandia Motorsports Park is where I'll be cutting my teeth for now. At some point I'll make trips to better tracks when time and money permit.

Were any alignment adjustments needed after the install of the MP springs? I really would like to get the springs on sooner than later for both the handling improvement and also aesthetics. The springs are a pretty cheap mod and can be reversed pretty easily if in the future I choose a better option or I don't like the ride or look.

As far as tires go I don't see having any other choice but to buy a set of track wheels and mount track tires on them. This might be further down the road when I get a sense for how much track time I can actually get.

BTW, I have a widebody RE with PS4's at about 50% tread. Too much fun to be had. OEM tires lasted me about 4K miles. I'm at 9K on this set so I'm getting better(ish).
I have not modified my camber after installing the MP springs. The results work well for me at a little less than -2 deg in the front and close to -1.5 in the rear from memory.
However, you have the AAD parts. If you have them already I'd install them if you are doing springs.
When you have your alignment done be very careful about rear toe. Any thrust angle in the rear has caused my car to walk around on acceleration. It's really disconcerting. I'd stay near 0 toe or a small amount toe in at the rear with as close to zero thrust angle as I could get.
 
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