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I hope this isn't a repost. Here's the 2015 specs that includes the Hellcat. Thought I'd post it in this section due to all the buzz lately.

Bernie
 

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Man, that's a heavy bastard. Over 4400lbs.
 

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Now we know why it needs 707 HP! LOL
 

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I'm curious with what the fuel consumption will be with the Hellcat. It's heavier, won't have cylinder deactivation like the other Hemis. But the 8 speed with the tall 2.62 axle ratio should help offset that, on the highway anyway.
 

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I'm curious with what the fuel consumption will be with the Hellcat. It's heavier, won't have cylinder deactivation like the other Hemis. But the 8 speed with the tall 2.62 axle ratio should help offset that, on the highway anyway.
This thing might drink gas like a 400lb alcoholic drinks booze........but wont give a damn.....:)
 

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I'm a little disappointed that they took away the steep 6th gear on the manual cars. The 392 gets a 0.50:1 6th gear but the hellcat gets 0.63:1 6th. Event with the hellcat getting a 3.70 rear gear instead of a 3.90 that over drive isn't near as much. Even the auto will be better. I like driving my 2012 now where 2000 RPMs in 6th gear is almost 90mph. Great for cruising. That's one more thing that pushes me closer to going auto.
 

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I'm a little disappointed that they took away the steep 6th gear on the manual cars. The 392 gets a 0.50:1 6th gear but the hellcat gets 0.63:1 6th. Event with the hellcat getting a 3.70 rear gear instead of a 3.90 that over drive isn't near as much. Even the auto will be better. I like driving my 2012 now where 2000 RPMs in 6th gear is almost 90mph. Great for cruising. That's one more thing that pushes me closer to going auto.
Yeah by my math looks like 2050 rpm will be 75 mph now on M6... 90 will be 2460 rpm. But I'm ok with a 3.70 rear...the 2.62 rear in the auto seems super high to me...never had anything with less than 3.90 that I can think of... but the 8 speed I have in my truck has 3.91 rear end with same gear ratios and does well. First gear is SILLY low though at 4.71 - takes it to about 5mph with a kick! lol

On an auto if the rear end is only 2.62 then you would be at about 100mph at 2050 rpm. Assuming the online calculator I am using is right. and 75mph would be 1550 rpm. Seems low...
The PDF does show overall top gear manual at 2.33 vs 1.76 for the auto as well.

BUT doing the math if run to an assumed 6,000 rpm redline (and not considering wind drag) gears don't run out until 218 mph or so on a 6 speed... but with that HIGH 2.62 in the back of an auto redline would take it WAY over that top speed...

Now I'm just confused...ha. I prefer manual in fun to drive weekend racer type cars...but auto would be faster and seemingly much better on the highway with the selected gearing...I don't see why they couldn't have left 6th somewhere around .50 or even .55 for the 6 speed... I'm sure they have valid reasons.
 

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BUT doing the math if run to an assumed 6,000 rpm redline (and not considering wind drag) gears don't run out until 218 mph or so on a 6 speed... but with that HIGH 2.62 in the back of an auto redline would take it WAY over that top speed...
My math came out to 216 mph top end on a 6 speed, so your math looks spot on to me.





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My math came out to 216 mph top end on a 6 speed, so your math looks spot on to me.
Then the auto runs out of revs and gears around 250 mph with that 2.62 high geared rear end and 8th gear! I'd like to know what shift points and rpm ranges in gears are. I'll dig up a calculator I used to figure out transmission setups when I was working on my Blazer and plug numbers in and see. Must not shift to 8th until 65 or 70 mph. The auto might actually get decent highway mpg! Not that I care... Certainly not my goal to conserve fuel with the car. :)
 

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Then the auto runs out of revs and gears around 250 mph with that 2.62 high geared rear end and 8th gear! I'd like to know what shift points and rpm ranges in gears are. I'll dig up a calculator I used to figure out transmission setups when I was working on my Blazer and plug numbers in and see. Must not shift to 8th until 65 or 70 mph. The auto might actually get decent highway mpg! Not that I care... Certainly not my goal to conserve fuel with the car. :)
I plan on using the Hellcat as a daily driver. Is it too much to ask that it smokes tires, out runs the blue oval and bow tie boys, and gets good gas mileage? Is that too much?


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Then the auto runs out of revs and gears around 250 mph with that 2.62 high geared rear end and 8th gear! I'd like to know what shift points and rpm ranges in gears are. I'll dig up a calculator I used to figure out transmission setups when I was working on my Blazer and plug numbers in and see. Must not shift to 8th until 65 or 70 mph. The auto might actually get decent highway mpg! Not that I care... Certainly not my goal to conserve fuel with the car. :)
according to an online calc, here are the top speeds for each gear, assuming a 6000 rpm redline and tire size 275/40/20:

1) 42 mph
2) 62 mph
3) 93 mph
4) 117 mph
5) 151 mph
6) 195 mph
7) 233 mph
8) 293 mph

rpms at highway speeds (60 - 65mph) are in the 1300 rpm range.
the car will cross the finish line in the 1/4 mile in 5th gear, assuming a trap speed > 120 mph
 

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I plan on using the Hellcat as a daily driver. Is it too much to ask that it smokes tires, out runs the blue oval and bow tie boys, and gets good gas mileage? Is that too much?

I'm thinking it will likely be 12-13 mpg city and 16-18 mpg hwy on M6 and then A8 will be 13-14 city and 18-20 hwy.
 

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according to an online calc, here are the top speeds for each gear, assuming a 6000 rpm redline and tire size 275/40/20:

1) 42 mph
2) 62 mph
3) 93 mph
4) 117 mph
5) 151 mph
6) 195 mph
7) 233 mph
8) 293 mph

rpms at highway speeds (60 - 65mph) are in the 1300 rpm range.
the car will cross the finish line in the 1/4 mile in 5th gear, assuming a trap speed > 120 mph
I was just about to sit down and compare the two trans and figure this out! Saves me a step. LOL at 293 mph...I think wind limitations will not allow more than about 210 mph... But WOW on the highway it's just chugging along at 1500 rpm at 70! Might get decent gas mileage with the A8! Can't wait to see specs.
 

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I'm thinking it will likely be 12-13 mpg city and 16-18 mpg hwy on M6 and then A8 will be 13-14 city and 18-20 hwy.
I'll bet it does better than that. My M6 392 averaged almost 25 mpg (24.8 or 24.9) highway on a recent trip to Virginia. That was around 80mph average speed. 100% stock. I think the 6.2 will be a pretty efficient motor. New PCM with killer processors on it too.
 

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I was just about to sit down and compare the two trans and figure this out! Saves me a step. LOL at 293 mph...I think wind limitations will not allow more than about 210 mph... But WOW on the highway it's just chugging along at 1500 rpm at 70! Might get decent gas mileage with the A8! Can't wait to see specs.
Has anyone looked up the 8 speed in the 392 SRT Charger? That might give us something to compare it to, vs. the old 5 speed auto.


5 sp vs. 8 sp = % gain with 392... interpolate that into the Hellcat 370 6.2, maybe?



.,
 

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I'll bet it does better than that. My M6 392 averaged almost 25 mpg (24.8 or 24.9) highway on a recent trip to Virginia. That was around 80mph average speed. 100% stock. I think the 6.2 will be a pretty efficient motor. New PCM with killer processors on it too.

Yeah I remember when mine was stock...it did about the same. MPG is so subjective though...depends how you drive, where, what you haul around (trunk full and passengers vs just a small driver makes a difference), fuel, and mostly how much you press on the GO pedal lol.

My Challenger initially got 24-25 mpg on highway when it had wider tires and exhaust only. Now...an extra 100 hp later... I get 12-13 city and maybe 16-17 highway BUT I'm on the gas a LOT... You are likely correct on the A8 and more mpg but I don't think the 6 speed will do as well with the lower 6th gear.

Smaller displacement helps as well as forced induction CAN help with efficiency but they put 60 lb injector in for a reason...because it pumps a LOT of fuel in. I doubt even the A8 gets better than say 16 city and 22 hwy...max. Hope to see these numbers within a week or two... Not that it would sway my purchase lol. As long as it's not insane like 8 mpg city and 12 hwy .... I'm in!
 
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