Just an fyi, Dodge noted in it's press release that the Demon has a top speed of 168mph. I'm guessing it's a gearing limitation.
Demon on the Loose...
- Thread starter TFStang
- Start date
Just an fyi, Dodge noted in it's press release that the Demon has a top speed of 168mph. I'm guessing it's a gearing limitation.
And that's likely because it's geared as a 1/4 Mile Drag Car and not a top-speed Mile Runner.
Some one into that could just regear and add more power however.
- Joined
- Mar 30, 2017
- Messages
- 216
You have to respect the dedication.
The 168mph is because of the drag radials haha. They aren't legally going to allow it to go faster than the tire is specced. That's an open shut lawsuit.
It has a 3.09 rear end with a 28" tall tire and a 1.0 6ths, .84 7th and .67 8th guys.
175mph in 6th@ 6500
208mph in 7th@ 6500
261mph in 8th@ 6500
You guys kill me with this crap.
It would have to have a 6.x rear to crap out at 168mph because of gearing hahahaha
It has a 3.09 rear end with a 28" tall tire and a 1.0 6ths, .84 7th and .67 8th guys.
175mph in 6th@ 6500
208mph in 7th@ 6500
261mph in 8th@ 6500
You guys kill me with this crap.
It would have to have a 6.x rear to crap out at 168mph because of gearing hahahaha
4.8* read gear set. 6.0 would only run 135ish.
- Joined
- Mar 30, 2017
- Messages
- 216
So you think the quicker way to run the 1/4 mile is to use all eight forward gears, two of which are overdriven, in the first 1320'?
The lack of real world knowledge becomes more evident every post. Take it fwiw.
- Joined
- Mar 30, 2017
- Messages
- 216
Top speed happens in sixth gear, 1:1, then factor in aerodynamics to get to 168.
Top speed happens when the ecu cuts power as it registers 168mph.
It could have the aerodynamics of a semi truck and still break 170mph with 840hp. Case in point, 750whp diesel Chevys and fords hit 170mph.
Remove the factory speed limiter. The car will easily do 200mph.
A 707hp hellcat does 190+ and is 300lbs heavier, has 133 fewer hp, the same gearing, and so on.
The top speed has nothing to do with being in a 1:1 gear. A c6 z06 will do 175~ in 4th. It's top speed is 198 in 5th. People have gotten 203+ going to 7200+ rpm in 5th. 5th is a .74 iirc in that car.
It's not wise to agressively acceleration any gear smaller than a 1:1, but people do so every day in every type of racing.
It could have the aerodynamics of a semi truck and still break 170mph with 840hp. Case in point, 750whp diesel Chevys and fords hit 170mph.
Remove the factory speed limiter. The car will easily do 200mph.
A 707hp hellcat does 190+ and is 300lbs heavier, has 133 fewer hp, the same gearing, and so on.
The top speed has nothing to do with being in a 1:1 gear. A c6 z06 will do 175~ in 4th. It's top speed is 198 in 5th. People have gotten 203+ going to 7200+ rpm in 5th. 5th is a .74 iirc in that car.
It's not wise to agressively acceleration any gear smaller than a 1:1, but people do so every day in every type of racing.
Fourcam what are you talking about when you say 8 gears in the quarter mile? I just posted that the damn car does 168mph in 6th gear at 6500rpm. How is it getting through all 8 gears by 140mph if it's able to do 168 in 6th?
Real world? I don't give a flying f*ck what world you live in, in the real world, the car is limited to 168 because the tires are rated to 168. It has nothing to do with aero or gearing.
Real world? I don't give a flying f*ck what world you live in, in the real world, the car is limited to 168 because the tires are rated to 168. It has nothing to do with aero or gearing.
A Range Rover SVR does 162mph with 550hp. Aerodynamics? .38 drag coefficient. The hellcat challenger has a .38 cd as well.
The demons is going to be tops .40
You have to be trolling or bullsh*tting.
The demons is going to be tops .40
You have to be trolling or bullsh*tting.
- Joined
- Mar 30, 2017
- Messages
- 216
When did I say anything about top speed having to do with a direct drive gear scenario?
Do the math on a regular hellcat with 2.62 rear end. It's in 6th gear at 190mph+.
- Joined
- Mar 30, 2017
- Messages
- 216
My point was that the car is in fact optimally geared for the 1/4 mile as is.
Dude you are completely misinterpreting what I posted.
I replied to the guys thinking it might need better gearing or aero by doing the math and showing the top speed in 6th, 7th and 8th.
It's not edited or revised. Go look. It's still there. It's 2 posts above the one where you claim I think the car goes through all 8 gears to reach 140mph.
You misinterpreted when I said "4.8 rear*, not 6.0. A 6.0 would only run 135ish" as saying 6th gear only does 135 (I'm assuming)
In the post prior to that I had joked that the car would need something idiotic like a 6.0 rear end to be limited to 168 because of gearing.
I then did the math and found it would be limited to 168 with a 4.8 rear gear set.
I replied to the guys thinking it might need better gearing or aero by doing the math and showing the top speed in 6th, 7th and 8th.
It's not edited or revised. Go look. It's still there. It's 2 posts above the one where you claim I think the car goes through all 8 gears to reach 140mph.
You misinterpreted when I said "4.8 rear*, not 6.0. A 6.0 would only run 135ish" as saying 6th gear only does 135 (I'm assuming)
In the post prior to that I had joked that the car would need something idiotic like a 6.0 rear end to be limited to 168 because of gearing.
I then did the math and found it would be limited to 168 with a 4.8 rear gear set.
It's geared well for the quarter mile given the launch/traction control and transmission they have. Keep in mind drag racing with a 7.01:1 first gear that does less than 25mph in an 840hp car is not normal or optimal. The car is in 3rd to reach 60mph. Watch dodges release video, the presenter clearly states that.
Unless you use a lot of digital traction/launch control, this would be a terrible idea. Most drag cars run 2-3spd setups to reach 140-175+ trap speeds with 500-800hp. Their first gears usually stretch well into 50-70mph. Th400's and c4's do not have short 1st gears, 2.44-2.46 respectively. That's about the zf890hp's 3rd gear for comparison.
I think dodge did phenomenal with this car. I don't get what your sniping at me for. I'm positive you are misreading something I posted
Unless you use a lot of digital traction/launch control, this would be a terrible idea. Most drag cars run 2-3spd setups to reach 140-175+ trap speeds with 500-800hp. Their first gears usually stretch well into 50-70mph. Th400's and c4's do not have short 1st gears, 2.44-2.46 respectively. That's about the zf890hp's 3rd gear for comparison.
I think dodge did phenomenal with this car. I don't get what your sniping at me for. I'm positive you are misreading something I posted
I'm lost by what you were clearing up here regarding my post that the 3.09 rear, 28" tire, and 1:1 6th allow the demon to do 175mph@6500.
Also, this was my point all along that it's limited to 168mph because it has w rated tires which legally are 168mph rated
Seems like you got a little too excited bud. I would dial it back a little.
It's been proven over and over again that, generally speaking, cars reach their top speed in the 1:1 gear. When you put the car in an overdrive gear, again, generally speaking, the car slows down because it doesn't have enough torque or horse power to make the car accelerate or even maintain its speed.
So, regardless of what the math looks like for any gear beyond the 1:1, it's not going any faster than the top speed in the 1:1 gear. This is what is very commonly referred to as "limited by gearing". Changing the rear diff gears and tire size can move those numbers around for you a bit, when when you are out of revs in 1:1, you're pretty much done.
Sure I'm worked up. I have a guy saying I'm making posts from another world, and you guys are the ones passing off incorrect info as a fact.
So let's take the assertion that it's because of 1:1.
6500rpm is going to hit 175mph. The redline is above that if I recall correct. Explain the extra 7mph above 168mph. I'll wait.
If the car is accelerating at around .4g at 140mph, it will not drop to weed range by 168 causing it to be unable to rap out its 4th gear.
This idea that the car reaches its top speed in a 1:1 is fine in a stock 150hp Corolla with no torque. Except if that isn't the case anymore. That car even reaches a higher speed in its overdrive gears.
It would be much easier to compose a list of cars than reach a higher speed in their overdrive gears than it would be to compose one about cars that do not.
Go drive a stock Subaru BRZ. 5th or 4th (manual/auto) are the 1:1 gears. Both reach ~127mph. The listed top speed for both cars is 137-147mph.
Again, thatcar has a terrible powerband for acceleration. Very little torque. It reaches its top speed in overdrive.
So let's take the assertion that it's because of 1:1.
6500rpm is going to hit 175mph. The redline is above that if I recall correct. Explain the extra 7mph above 168mph. I'll wait.
If the car is accelerating at around .4g at 140mph, it will not drop to weed range by 168 causing it to be unable to rap out its 4th gear.
This idea that the car reaches its top speed in a 1:1 is fine in a stock 150hp Corolla with no torque. Except if that isn't the case anymore. That car even reaches a higher speed in its overdrive gears.
It would be much easier to compose a list of cars than reach a higher speed in their overdrive gears than it would be to compose one about cars that do not.
Go drive a stock Subaru BRZ. 5th or 4th (manual/auto) are the 1:1 gears. Both reach ~127mph. The listed top speed for both cars is 137-147mph.
Again, thatcar has a terrible powerband for acceleration. Very little torque. It reaches its top speed in overdrive.
On a truck or something approaching .50 drag coefficient, sure. Especially when it's a 4 speed auto and drops from 1:1 down to .50
Something like a 90's Chevy truck will have a very hard time reaching a higher speed in 4th vs 3rd.
Something like a 90's Chevy truck will have a very hard time reaching a higher speed in 4th vs 3rd.
- Joined
- Mar 30, 2017
- Messages
- 216
Since wind resistance increases four fold vs velocity at vmax a demon will need a lot more than 100 extra HP over a 190+mph hellcat to break 200mph.
Which doesn't even take into account the added resistance of the fender flares, tires sticking out, etc that the demon has added. For frame of reference I've seen the same car go 174 then 181mph in the same standing mile event. With wheel well covers it picked up 7mph up top. Small stupid aero changes mean a lot as far as vmax.
Either way dodge obviously didn't just talk about building a 1/4 mile car. The tires may be the official liking factor but the demon wasn't geared for top speed.
The first fre gears are short because it's a purpose built car and the first 60' dictates any drag race.
Users who are viewing this thread
