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Discussion Starter · #1 ·
Why does the 2015 charger have a top speed of 204 mph with 707 HP and the redeye has top speed of 203 mph?
Do fender flares on Widebody negate 90 HP??
 

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2020 Challenger Hellcat Redeye Wide Body
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Why does the 2015 charger have a top speed of 204 mph with 707 HP and the redeye has top speed of 203 mph?
Do fender flares on Widebody negate 90 HP??
The wider tires add quite a bit of drag along with the flares. The faster you go it takes exponentially more hp to overcome additional drag.
 

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The faster you go it takes exponentially more hp to overcome additional drag.
The required power is pretty close to the cube of the speed. Everything else being the same, going from 707 HP to 797 HP should bring the top speed from 204 mph to 212 mph. So these extra 90 HP are only good for ~8 mph and can be easily offset by higher drag. There is a good reason why Hellcats don't come with splash guards...
 

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I'd also make the argument that the 707hp Hellcat is slightly underrated also and it probably closer to 725-730hp which means that gap isn't quite as large as it seems either.
 

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I'd also make the argument that the 707hp Hellcat is slightly underrated also and it probably closer to 725-730hp which means that gap isn't quite as large as it seems either.
There is a thread here showing the Redeye actually having 814 HP at the crank and my Redeye clearly feels a lot quicker than my 2016 Hellcat did. The 90 hp difference sounds about right
There is also the standard body Redeye to consider. A little lighter, less drag and skinnier harder all-season tires. With the 2.62 gear should have the highest top speed of any Hellcat from the factory.
 
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2020 Challenger Hellcat Redeye Wide Body
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The required power is pretty close to the cube of the speed. Everything else being the same, going from 707 HP to 797 HP should bring the top speed from 204 mph to 212 mph. So these extra 90 HP are only good for ~8 mph and can be easily offset by higher drag. There is a good reason why Hellcats don't come with splash guards...
Not sure about the exact formula. Even with all things being the same (standard body Challenger RE) the 90 extra hp certainly isnt getting it to 212 mph. When youre up into the high triple digits it takes a lot more hp to overcome even the same drag and gets increasingly more difficult to do it.
 

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There is a thread here showing the Redeye actually having 814 HP at the crank and my Redeye clearly feels a lot quicker than my 2016 Hellcat did. The 90 hp difference sounds about right
There is also the standard body Redeye to consider. A little lighter, less drag and skinnier harder all-season tires. With the 2.62 gear should have the highest top speed of any Hellcat from the factory.
Based on the RWHP dyno's Ive seen, the 797hp rating is pretty close but almost all 707HP cats dyno enough to justify 725'ish. I'm not doubting that the Redeye feels a little quicker, it should since its making at least 60-70hp more, to most people that should be somewhat noticeable.
 

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Not sure about the exact formula. Even with all things being the same (standard body Challenger RE) the 90 extra hp certainly isnt getting it to 212 mph. When youre up into the high triple digits it takes a lot more hp to overcome even the same drag and gets increasingly more difficult to do it.
And even more so in a car that isn't that aerodynamic.
 

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Based on the RWHP dyno's Ive seen, the 797hp rating is pretty close but almost all 707HP cats dyno enough to justify 725'ish. I'm not doubting that the Redeye feels a little quicker, it should since its making at least 60-70hp more, to most people that should be somewhat noticeable.
How a fast a car feels is generally subjective and there never seems to be enough power.
I don't know of there was something wrong with my 19' ZL1 a10 but it didn't feel a whole faster then my 16' 2SS and that was about a 200 hp difference.

Whatever the actual horsepower/torque difference, my redeye doesn't feel just a little quicker, it feels a lot quicker from any speed and is clearly noticeable to me and people that have been in my old hellcat and redeye.

I'm not into street racing my self but have seen a bunch of roll race vids on you tube where cars are hanging with regular stock hellcats and same car getting gapped by the stock redeye.
 
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How a fast a car feels is generally subjective and there never seems to be enough power.
I don't know of there was something wrong with my 19' ZL1 a10 but it didn't feel a whole faster then my 16' 2SS and that was about a 200 hp difference.
Whatever the actual horsepower/torque difference, it doesn't feel just a little quicker, it feels a lot quicker from any speed and is clearly noticeable to me and people that have been in my old hellcat and redeye.

I'm not into street racing my self but have seen a bunch of roll race vids on you tube where cars are hanging with regular stock hellcats and same car getting gapped by the stock redeye.
Hard to tell by watching internet videos. No one is ever honest about what's been done to the cars, and don't even get me started on the skill of the drivers being a huge wildcard.
 
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2.62 gear should have the highest top speed of any Hellcat from the factory.
Looking at the gear/speed calc, the 2.62 and 3.09 rear should hit the same top speed @6200, 203. 2.62s at top 6th, 3.09s top of 7th ,,

It looks like Dodge chose those ratio;s for that reason.

Redeye's with 3.09's should technically hit 210 @6400 top of 7th but as the others posted, that ain't happening stock power in a car that's aerodynamic as a brick.

And even more so in a car that isn't that aerodynamic.
My 2018 Gen3 Mustang dyno'd 470rwhp. with the A10 hit 180 at 6600 in 8th and eventhough peak power was at 6900, it absolutely wouldn't go any faster. Simply not enough power to overcome drag at that point.

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Not sure about the exact formula. Even with all things being the same (standard body Challenger RE) the 90 extra hp certainly isnt getting it to 212 mph.
The formula is pretty accurate at those speeds. As for the standard body RE top speed (I'm not sure what it is), the HP difference with the regular HC is most likely less that 90 HP since the 707 HP is known to be underrated. Knowing both top speeds and one of the HP, it's easy to calculate the other HP with a decent accuracy.
 

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Hard to tell by watching internet videos. No one is ever honest about what's been done to the cars, and don't even get me started on the skill of the drivers being a huge wildcard.
Best way to tell the actual difference in power between a known stock hellcat and known stock Redeye would be testing 60-130 with a dragy on the same day, time and road. Same day same 1/2 mile test would be nice to see the difference in mph.
I don’t know why you all care about the top speed differences, these cars in any form acceleration hit a wall around 190ish stock.
The redeyes extra power gets it there faster.
 

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The formula is pretty accurate at those speeds. As for the standard body RE top speed (I'm not sure what it is), the HP difference with the regular HC is most likely less that 90 HP since the 707 HP is known to be underrated. Knowing both top speeds and one of the HP, it's easy to calculate the other HP with a decent accuracy.
They say the 797 is actually 812 too. So many variables.
 

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Looking at the gear/speed calc, the 2.62 and 3.09 rear should hit the same top speed @6200, 203. 2.62s at top 6th, 3.09s top of 7th ,,

It looks like Dodge chose those ratio;s for that reason.

Redeye's with 3.09's should technically hit 210 @6400 top of 7th but as the others posted, that ain't happening stock power in a car that's aerodynamic as a brick.



My 2018 Gen3 Mustang dyno'd 470rwhp. with the A10 hit 180 at 6600 in 8th and eventhough peak power was at 6900, it absolutely wouldn't go any faster. Simply not enough power to overcome drag at that point.

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1,024 whp got me to 203mph on an airstrip run. It could have likely made it to 207, maybe 210 as a pipe dream, but this was not a 6,000ft runway.
570965
 

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Discussion Starter · #16 ·
Curious, will I notice the difference in acceleration of my Redeye Charger vs my Hellcat Charger?
 

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1,024 whp got me to 203mph on an airstrip run. It could have likely made it to 207, maybe 210 as a pipe dream, but this was not a 6,000ft runway. View attachment 570965
Pretty, My old turbo 3v hit 196 on the Mile with a .63 OD T56 and 4.10 rear, and feeding it corn, ran out of gear.

Might, and I mean Might have hit 205 with 3.90's, I know it would've if I'd gazzed it but I'm leary of hitting even a small shot of giggle gas at that kinda speed.

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Discussion Starter · #19 ·
As someone who has made the jump, my Redeye Charger is definitely noticeable.
One more question. On my Hellcat I am constantly spinning out the wheels. They had no bite and i was always a heart beat from losing control of my ass end. Does the wide body and 305s make a big difference?
 

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One more question. On my Hellcat I am constantly spinning out the wheels. They had no bite and i was always a heart beat from losing control of my ass end. Does the wide body and 305s make a big difference?
Wider tires will help somewhat, but replacing the stock tires with something really sticky (I use R888R in the back) makes a huge difference. That said, even with R-compound tires, you can still spin them easily, but at least you can get a real acceleration before you do. Stock Pirellis are good for burnouts and not much else.
 
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