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As motorheadmike pointed out: the SAE measured on the 2019 + is 745 HP.
I can't account for why your 2019 is underperforming compared to your 2017, I can only list the SAE J1349 actual "measured" HP results/data:
2015 - 2017 714 HP @ 6200 RPM (707 advertised)
2018 730 HP @ 6200 RPM (707 advertised)
2019 - 2020 745 HP @ 6200 RPM (717 advertised)
2019 - 2020 Red Eye 803 HP @ 6300 RPM (797 advertised)
2021 Super Stock 812 HP @ 6400 RPM (807 advertised)
 

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So what I've been reading is if I go get it custom to send the guards should wake up and run a lot better than it does now because I ran it again today car still would go no quicker than 1120s and only a hundred and twenty four and had crappy 60ft times wouldn't do better than 168 both of them were in the 1700 and I'm running the 18 in Mickey Thompson SS and the track was prepped
Just to let you know, the M/T SS's don't bite as good as the M/T street R's. I have used both and no comparison the street R's are better. You just can't get them in 20 inch. Most use 17 inch, I have 18's on mine. The 60 foot is 1.52 to 1.55. Just had tuner put more timing in from 1500rpm to 3500rpm to try to get to the 1.48 if it bites. I am trying to improve the ET while not going over 135mph. Track asked me not to go over 135.99 LOL The 100 octane tune from OST DYNO is great, hoping to run 10.30's on just tune only in 1700DA. It's real high here in Phoenix now 3500DA to 4700DA this time of year. I have the demon killer springs to put on and then go to the 3.09 gears.... I also have the ATI 10% lower to run right on 10.00. Also all stock with the drag pac best I could go was 11.009 @ 127 at 11:45 at night when it was cooler with 100 octane gas...
 

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This is interesting ....have you read the data logs from both cars? How much of a timing difference between the 2018 and the 2017 and earlier ? Super interested ..
I have looked at the logs of a friend's 17 and at 3500rpm he was getting 22.5 degrees and my 18 only had 19.5 runs were only 3 minutes apart, AIT and water temperatures were the same on both cars. No STKR and no other timing being pulled. Could compare the stock tunes in HPTUNERS side by side and the tune is just set with more timing at a faster rate. He now has a tune similar to mine and he runs 10.70's @ 132 or so. To my 10.40's @ 135. Mine also shifts at different RPM in different gears than his, I think that is so important to make the car run faster. That's why they raised the shift RPM in the demon/ redeye. I have to say my car is a few hundred pounds lighter too. (No sun roof in my car, rear seat delete, no passenger seat) I feel the 18's and newer car with the different blower and different engine parts (arp bolts, different cam profile) with the same tune are faster than the 17 and earlier cars. Just aside I found out the blower on the 1000hp 426 is a 3 liter compared to the 2.4 on the hellcat and the 2.7 on the demon/ redeye.
 
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Discussion Starter #26
I messed up on the tires they are 305 /45/18 RMickey Mickey Thompson drag radials the problem with the car is not 60 ft and not making the mph it's not spinning track is good weather was okay I compare them to notes with my Time Slips for my other car same area same altitude and air and weather and my 17 Hellcat was running 1090s 11 O's this one's running 11:33 miles an down 3 miles an hour my 2017 would run anywhere from 127 to 130 this one only runs best of 124 it's also 3mph in the 8th mile it runs 97mph when my Time Slips on my 2017 show 99 to 100 mph. And I'm not trying to brag but I'm not an amateur drag racer been Drag Racing for many years this is the first car that's ever gave me these kind of issues stock to stock I know all the little Hellcat tricks it's just not making the mile an hour and will not 60ft the other thing was there was a stock 2016 out there today went 11:02 at 127 the same time I ran 11:33 at 124 and me and the driver both weigh about the same and both cars were bone stock on drag radials but actually he was running 305 35 20 SS Mickey Thompsons
 

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Mine also shifts at different RPM in different gears than his, I think that is so important to make the car run faster.
The higher speed you are at when you shift, the more precisely you want the shift to match the best RPM for peak output. It was my assumption that the transmissions would shift at an ever-higher RPM as they went through the gear range from the factory. Not the case?
 

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Edited
what he said is edited below
I messed up on the tires: They are 305 /45/18 Mickey Thompson drag radials.

The problem with the car is not the 60 ft and not making the mph it's getting the tires not to spin.

The track is good, weather was okay. I compare them to notes with my time slips for my other car, same area, altitude, air, and weather, and my '17 Hellcat was running 10.90s - 11.0's

This one's running 11.33. Top speed is down 3 miles an hour.

My 2017 would run anywhere from 127 to 130; this one only runs a best of 124 it's also 3mph slower in the 8th mile; it runs 97mph whereas my time slips on my 2017 showed 99 to 100 mph. I'm not trying to brag but I'm not an amateur drag racer; I have been drag racing for many years. [Himmelkat's addendum: like Jay Gleason on a motorbike, some people's consistency is so well-established that any variations in results are more likely to be ANYTHING AT ALL but the driver being inconsistent or making rookie mistakes.]

This is the first car that's ever given me these kinds of issues comparing stock to stock.

I know all the little Hellcat tricks; it's just not making the miles per hour and will not 60ft at the same level. The other thing was this: There was a stock 2016 out there today that went 11:02 at 127 the same time I ran 11:33 at 124 and me and the driver both weigh about the same and both cars were bone stock on drag radials but actually he was running 305 35 20 SS Mickey Thompsons
 

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Here are the base, WOT, and IAT modifier timing tables from my 2019 and a 2016 Challenger; like I said sensitivity to the thresholds will dictate power potential. Pay close attention to the Aircharge (g) mass rows as they don't align. You will also need to know what the normal aircharge mass is for your car to make any assessment of what more timing could do. Additionally, there are other factors that come into play between the two cars - like cam timing.

My car is about 1.4g air charge (580g/s air mass and 11.5-12psi), 14* total timing (with 2 degrees pulled due to aircharge temp/IATs @142*F, idealy that would have been 16*), and no STKR.

2019:
2019.jpg


2016:
2016.jpg


In short, good air and good fuel is what the 2018+ cars need for top performance.
 

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It makes me wonder if having a truly outrageous aftercooler fluid radiator in front of the main radiator in addition to the primary cooler(s) it already has would mitigate IAT woes. If the aftercooler fluid were right at ambient temperature upon entry to the aftercooler, could it not be an advantage, overall? One may need to upsize one's engine radiator capacity to make up for the slightly increased radiator airflow temperatures, too.
Bigger aftercooler bricks, too...

I know with my car, in second or third gear on cold ambient days, it feels like it is trying to climb a wall at WOT. Truly impressive acceleration. It leads me to actually, for the first time in my life, be looking forward to the return of winter.

I return to my question, "What would it be like in far-sub-zero conditions?" What would the cars do in an environment where the built-in thermostats for oil, coolant, and supercharger fluid (if such exists) actually had to cycle off occasionally, or at higher load?

Considering that during the compression cycle, the air is raised, with 8.75:1 compression, 3500 degrees higher than it was, if the baseline temperature before mechanical compression was zero degrees, having an intake air temperature before supercharging of zero or lower would multiply the efficacy of the various cooling systems without risking "being too cold for combustion."

The primary negative impact would be the somewhat reduced fuel atomization, but, the intake air is never going to be below ambient temperature, especially AFTER the supercharger, and neither is the fuel, with the rails sitting over the engine, I would imagine.

Since the temperature increase during compression is based on temperature above absolute zero, which is minus 400 Fahrenheit, as an example, 8.75:1 compression on a 100 degree IAT would yield 500X8.75=4,375 degrees at top dead center of compression stroke.

If you could manage an IAT of minus fifty degrees temperature, (use pure propylene glycol coolant with NO water in this case, as it has a minus 70 freezing point,) your air temperature at TDC would be 350X8.75=3325 degrees, aka 1,050 degrees cooler than at 100 degrees. Even at the same power output, your piston crowns and exhaust valves, if nothing else, would be thanking you. You would want automated shutters over your radiator to prevent overcooling the fluid in the radiator when just cruising along.
 

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I have a 2015 and a 2020. I feel that so far the 2015 seems faster and more violent. Could be cause I only have 750 miles on the wb butttt I was thinking the same thing last week. 2015 is stronger and sounds alot better. Both are totally stock but the 15 is lowered
 

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The higher speed you are at when you shift, the more precisely you want the shift to match the best RPM for peak output. It was my assumption that the transmissions would shift at an ever-higher RPM as they went through the gear range from the factory. Not the case?
The stock tune shifts the trans 6150rpm in every gear. Their is run by in the first two gears, if you look at logs it can run by 6200rpm before it actually shifts. I have my car shift 1st-2nd 6400 the rest @ 6500 I do have other shift tunes but I would have to kill you if I told you...LOL
 

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I think there's actually a comparably "easy" gain to be had in the trans tune. Obvious you don't want to raise those shift points too far and wind up with spontaneous valvetrain disassembly. :eek: But there's definitely something to adding 300 or so RPM to your shift points.

If the 2015 engine tune is "better," why not flash that in? It's conservative enough to avoid the big badaboom, right?
 

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Timing isn't going to give you the gains that RPM will in these cars. Or air flow (which the 2018+ cars (allegedly) have over the pre-2018 cars with the revised blower).

Obviously a less sensitive/more aggressive tune will be more prone to delivering repeatable results. However, if the engine is closer to the ragged edge it is closer to catastrophe.

I'll take air mass over timing everytime.
 

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I think there's actually a comparably "easy" gain to be had in the trans tune. Obvious you don't want to raise those shift points too far and wind up with spontaneous valvetrain disassembly. :eek: But there's definitely something to adding 300 or so RPM to your shift points.

If the 2015 engine tune is "better," why not flash that in? It's conservative enough to avoid the big badaboom, right?
Corben Dallas speaking to a victim of the big badboom.
 

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The stock tune shifts the trans 6150rpm in every gear. Their is run by in the first two gears, if you look at logs it can run by 6200rpm before it actually shifts. I have my car shift 1st-2nd 6400 the rest @ 6500 I do have other shift tunes but I would have to kill you if I told you...LOL
Tuco Salamanca? Literally my favorite character from Breaking Bad?
 

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Timing isn't going to give you the gains that RPM will in these cars. Or air flow (which the 2018+ cars (allegedly) have over the pre-2018 cars with the revised blower).

Obviously a less sensitive/more aggressive tune will be more prone to delivering repeatable results. However, if the engine is closer to the ragged edge it is closer to catastrophe.

I'll take air mass over timing everytime.
The torque is high and the power keeps climbing right until it slams face-first into the rev limiter. The limitation is the reciprotating assemblies.
 

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Timing isn't going to give you the gains that RPM will in these cars. Or air flow (which the 2018+ cars (allegedly) have over the pre-2018 cars with the revised blower).

Obviously a less sensitive/more aggressive tune will be more prone to delivering repeatable results. However, if the engine is closer to the ragged edge it is closer to catastrophe.

I'll take air mass over timing everytime.
The timing pull accounts for a substantial loss on this car. That’s a huge difference, and this would account for why the newer cars have been performing worse in the tests in magazines. Heat soak and higher charge air temps, along with fuel quality, absolutely wrecks output with the way the factory tune is setup on the newer vehicles.

It makes me curious what changed, because the newer engines have a number of differences that make them mechanically better, but with in real world conditions those tables you posted are a massive power difference. It really explains why the newer vehicles feel almost embarrassingly slow on hot days.
 
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