[Jonx96]

This is what it looks like when you hit COT. This was on the highway coming home from an evening at the dragstrip. Watch the boost.

Scary it does that. It means you are leaving a safe limit for injector pulse widths. It bleeds boost to attempt to need less fuel….

 

[Vet Rider]

Scary it does that. It means you are leaving a safe limit for injector pulse widths. It bleeds boost to attempt to need less fuel….

Yeah you should have seen my logs. Bypass would open, injector DC would go to 125%, commanded lambda would go to .70 and the fuel pressure would drop to 20psi at the rail. This car was throwing out the boat anchor.

 

[Vet Rider]

Most already know, but I sold this car and bought another ZL1. Not to be a hater but my ZL1 doesnt care about the weather. It just rips. Sure it has its own version of blower car heat soak quirks, but it never falls on its face no matter how hot it gets while Im ripping on it. I was never able to get a clean pass out of the hellcat. And in hotter weather, I've ran faster and more consistent with my stock ZL1 then I ever could manage in hellcat. It was a shame. I really wanted that hellcat. But I've been soured since this and wont ever go back unless I could find a steal deal on a 2019 challenger RE. My shit show car was a 21 charger HC I ordered new from DC. Waited 4 months for it. It was gone in less time than I waited for it.

 

[Greengohellcat]

That blasted cat replacement and ecm reflash...the dealer had no information about what was actually in the flash and there was no way for the customer to definitively find out.

I think that this lack of info was deliberate- I would NOT have done the recall knowing that the car would bleed horsepower like that.
I watched the dealer remove my perfect condition cats and wondered why bother?

 

[Jonx96]

Most already know, but I sold this car and bought another ZL1. Not to be a hater but my ZL1 doesnt care about the weather. It just rips. Sure it has its own version of blower car heat soak quirks, but it never falls on its face no matter how hot it gets while Im ripping on it. I was never able to get a clean pass out of the hellcat. And in hotter weather, I've ran faster and more consistent with my stock ZL1 then I ever could manage in hellcat. It was a shame. I really wanted that hellcat. But I've been soured since this and wont ever go back unless I could find a steal deal on a 2019 challenger RE. My shit show car was a 21 charger HC I ordered new from DC. Waited 4 months for it. It was gone in less time than I waited for it.

ZL1 eww narrowbands

 

[Vet Rider]

ZL1 eww narrowbands

I didn’t say it was perfect lol.

 

[moparjim]

Yeah you should have seen my logs. Bypass would open, injector DC would go to 125%, commanded lambda would go to .70 and the fuel pressure would drop to 20psi at the rail. This car was throwing out the boat anchor.

Sounds very close to what nonsense was going on with mine after the recall.

 

[HP_Addict19]

For comparison, when mine hit cot it was making 535rwhp on the dyno. After the tune on the same dyno it made 734rwhp. That was still completely stock except the tune all on 93 in 90*+ temps same dyno. Thats how bad COT was hitting. When the car was cold before the tune it made 655rwhp on that same dyno. This is a 21 normal HC Charger WB. NON RE.

I wonder if Dodge tuned the new Hellcats COT that way because the Redeye, SS and Jailbreak make more power? More power equals More Heat. Edit: But, I also know those 3 other faster Hellcats have the 6.2 L HO engine with stronger internals.

If I have the same COT issues, I’ll just get it tuned. knock on wood

I’m new to Hellcats but I remember Diablosport made a hand held tuner that plugged into the diagnostic port under the dash on the 03-04 Mustang Cobras. I think they make those for Hellcats too.

 

[Vet Rider]

I wonder if Dodge tuned the new Hellcats COT that way because the Redeye, SS and Jailbreak make more power? More power equals More Heat.

If I have the same COT issues, I’ll just get it tuned. knock on wood

I’m new to Hellcats but I remember Diablosport made a hand held tuner that plugged into the diagnostic port under the dash on the 03-04 Mustang Cobras. I think they make those for Hellcats too.

Nah its just an EPA thing. The EPA came down hard on everyone over emissions and this was Dodge's way to protect the cats from failure and keep them legal. This is what I've heard, obv take with many grains of salt.

 

[HP_Addict19]

Nah its just an EPA thing. The EPA came down hard on everyone over emissions and this was Dodge's way to protect the cats from failure and keep them legal. This is what I've heard, obv take with many grains of salt.

Good point. About the EPA.

How did you tune your car? To fix that COT issue. Did your tuner use a flash tuner or chip?

 

[Vet Rider]

Good point. About the EPA.

How did you tune your car? To fix that COT issue. Did your tuner use a flash tuner or chip?

HP tuners. I bought all the hardware and sent out the PCM for them to unlock. Then installed it all and flashed the tunes emailed to me. Sent logs back and forth with tuner.

 

[HC5120]

OK - it seems no one got what I was trying to say here - sorry.
I was underwhelmed as it took so long to accelerate from 90 mph to 165 mph - but now I see it is not me - it is what is expected).
So I looked at multiple Redeye top speed runs on Youtube and timed their results. It is clear that a Redeye (like mine) needs ~14 seconds to go from 90 mph to 165 mph. That was the same result at my Hellcat. So nothing wrong with my car. In these 14 seconds you (and Me) will use up ~2600 feet - which is what I observed on the 3,500 ft straightaway at Poconos. So going 0-90mph (about 7 seconds) is MUCH quicker than going 90-165 mph (about 14 seconds).

You need to gather more info about what's going on with the car. At minimum, what's the air intake temp throughout the run and especially going into the straightaways, and like someone said, log it, if possible.

I’ll keep it simple. If your stock hellcat/Redeye intake air temp is over 100 degrees the car is cutting timing. If it’s over 140 degrees it’ll cut timing even further. I like running my car ideally when I can keep intake air temps under 100 degrees. Don’t forget to use the chiller to help cool it down!

My 16 HC starts to fall off when IAT hits about 115. Depending on IAT it runs between 6.80 and 7.05 in the 1/8 at 4500 DA.

Wow, I didn't plan to track (HPDE) any Redeye I purchase but this sure is interesting. I understand that heat is the enemy of power adder cars from drag strip experience and that high intake temps on a road course kill power. But your talking about power pulled for cat converter temps or oil cooling issues. So on a hot day in highway driving would it ever come into play or it's just pushing the car all out over time? So I get that you are PO'd but would the 717 HC really be any different? I just read so much about the larger supercharger, the power chiller, the beefed up internals, and the superior rear end and axles on the RE versus the Hellcat that I thought it was a no brainer that the RE was just a better engineered and superior car in every metric. So would you still say it's superior in every way except this one HPDE application?

The power chiller is basically worthless on a big track, isn't it? Once you use up the chilled coolant, which takes less than 15 seconds probably, I don't think it would be able to keep up with removing more heat in a race environment on a big track where you are pushing the car as hard as it will go. The chiller, from my understanding, and reading about it, and looking at posts on here, etc., is best for drag racing. But maybe someone who has tried to use the chiller on a big track can comment on whether it works well or not.

Doesn't seem like many people use superchargers on big tracks. That's probably because of the heat issue, not to mention it's more weight, too. But I am not a big track guy, so maybe someone can comment on that who goes to these types of events a lot.

Lastly, there will always be a faster car than whatever you're driving. Max out what you have. Focus on improving your times with what you have. My two cents anyways.

And most importantly have fun.

 

[matt someone with an SRT]

You need to gather more info about what's going on with the car. At minimum, what's the air intake temp throughout the run and especially going into the straightaways, and like someone said, log it, if possible.




My 16 HC starts to fall off when IAT hits about 115. Depending on IAT it runs between 6.80 and 7.05 in the 1/8 at 4500 DA.




The power chiller is basically worthless on a big track, isn't it? Once you use up the chilled coolant, which takes less than 15 seconds probably, I don't think it would be able to keep up with removing more heat in a race environment on a big track where you are pushing the car as hard as it will go. The chiller, from my understanding, and reading about it, and looking at posts on here, etc., is best for drag racing. But maybe someone who has tried to use the chiller on a big track can comment on whether it works well or not.

Doesn't seem like many people use superchargers on big tracks. That's probably because of the heat issue, not to mention it's more weight, too. But I am not a big track guy, so maybe someone can comment on that who goes to these types of events a lot.

Lastly, there will always be a faster car than whatever you're driving. Max out what you have. Focus on improving your times with what you have. My two cents anyways.

And most importantly have fun.

It’s not totally useless but you have a good point.. it’s still spinning the fans to push heat from the engine bay out the right side of the vehicle even though as you stated it has Exhausted the coolant reserve.

 

[16GoManGoHC]

I’ll keep it simple. If your stock hellcat/Redeye intake air temp is over 100 degrees the car is cutting timing. If it’s over 140 degrees it’ll cut timing even further. I like running my car ideally when I can keep intake air temps under 100 degrees. Don’t forget to use the chiller to help cool it down!

Remember, at WOT the AC compressor is turned OFF, so a power chiller is doing squat then. A friend of mine at Road America last year learned the hard way and killed his supercharger when the coolant temps went over 220° in the LTR coolant system and he wasn’t keeping an eye on gauges and kept on it.
Yes, these cars need better cooling for road courses!! Road course and continuous WOT use is where turbos and big air to air intercoolers shine!!!

 

[RB185AFM]

I can tell ya from the two sessions I ran this morning, these Redeye’s suck large in the heat! The DA is 4500’ that don’t help, but after a few laps this POS is pulling power due to excessive temps in the Cats and oil. I have seen oil temps over 290! Seems like over 275 it runs like hell anyway. We are not passing squat the way this is running. OP take it back to Dodge and tell them it don’t work HPDE driving on hot days. Cat overheat and inadequate oil cooler. I want my Hellcat back, these are not built to support the extra power with any additional cooling.

Anyone think a new C8 will be better? In our group that is 50/50 today. One is down, and I just dropped him at the Chev dealer. It can’t make it to the dealer from the track. It is parked at a gas station.

My C7 GS was hitting 285 degrees on ave

Remember, at WOT the AC compressor is turned OFF, so a power chiller is doing squat then. A friend of mine at Road America last year learned the hard way and killed his supercharger when the coolant temps went over 220° in the LTR coolant system and he wasn’t keeping an eye on gauges and kept on it.
Yes, these cars need better cooling for road courses!! Road course and continuous WOT use is where turbos and big air to air intercoolers shine!!!

Agreed! I’m hitting 270 degrees doing canyon runs on a 70 degree day!

Badass street car? Maybe the best!

Track car with that pesky stopping and turning, hell no! FI sucks on the track when your not dealing with crazy weight. The Redeye is fine for a novice to blast around the track in. If you have pace……going to get expensive and not going to be worth the cost in consumable or life span, IMO. Better to run your Redeye in some canyons and buy a built Miata for the track. It will be cheaper than trying to seriously track a 4500 pound car with 800 hp

 

[S8ER01Z]

Is there any indication of COT other than the boost dropping off?! I need to watch for this because I have noticed the Durango going into PIG mode and stops pulling like normal when it’s hot and I’ve not been going easy on it.

 

[Vet Rider]

Is there any indication of COT other than the boost dropping off?! I need to watch for this because I have noticed the Durango going into PIG mode and stops pulling like normal when it’s hot and I’ve not been going easy on it.

commanded lambda goes like .70, injector duty cycle goes to 125% or more. Mine also would have the fuel pressure drop at the rail too down to like 20psi when it’s supposed to be 80psi.

 

[JMAbacus]

This is what it looks like when you hit COT. This was on the highway coming home from an evening at the dragstrip. Watch the boost.

So the Vet Rider was kind enough to explain all the data logging details and power loss in a very well written DM. I understand the cars pulling timing as the IAT's go up. I know about heat soak. I get that the oil cooler is not really designed for extended track use and when the oil is overheated more power is pulled. All this is a non issue for me. But on the issue of COT (cat over temperature) killing boost this was something happening on "normal" highway driving with some WOT attempts. Seems like this type of driving is about the most common form of WOT. Your out cruising around or on a highway and see a long flat straightaway and go WOT from 50 up to whatever you deem safe (say 120). Seems like nearly all board members would have driven their RE's like this. Got a couple folks indicating they have lost boost like this. Do the lack of comments mean that most 21-22 RE owners just haven't seen any boost loss during highway driving going to WOT? I'm in the south so the ambient temp is going to be over 90F during daylight hours for the entire summer. Just trying to understand how common this COT boost loss might be during normal summer driving? Thanks for any input.

 

[S8ER01Z]

commanded lambda goes like .70, injector duty cycle goes to 125% or more. Mine also would have the fuel pressure drop at the rail too down to like 20psi when it’s supposed to be 80psi.

Appreciate that. I don’t have an unlocked PCM but I have HP Tuners for my LS6 car, I should be able to see that data logging at least. 🍻

 

[Vet Rider]

Appreciate that. I don’t have an unlocked PCM but I have HP Tuners for my LS6 car, I should be able to see that data logging at least. 🍻

Yeah you can log no problem. You’ll need the bypass cable installed and unlocked pcm before you can flash though.