Theres 1. My point was a majority of 7+ speed transmissions have 3 od
Thoughts on DCT
- Thread starter PowerWheels
- Start date
There may be 2, Ford hasn't released their spec yet.
Shift speed matters decidedly, as does the slip at launch to get the engine in to or keep it at the power band. This car would go mid 11@120 with wot shifts and a little clutch slip on the launch. The 12.1@115 he runs is not a bad or slow time, but it’s easy to see that the .5 second shifts add up to lost time and lost speed.
Compare that to this
Easy 4-5mph and ~ 1 second faster 40-120 pull.
If the gt500 delivers 70-90ms shifts and the demon is doing 150-200ms shifts, that’s a huge advantage to the gt500.
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For discussions sake, here is the calc ive used from the beginning for the GT500.
Top is known and estimated data of 2020 GT500, shift speed of .08
Bottom, exactly the same, shift speed slowed to .23
Result? .2 ET and ~2mph in the 1/4 mile, 0 other changes
Top is known and estimated data of 2020 GT500, shift speed of .08
Bottom, exactly the same, shift speed slowed to .23
Result? .2 ET and ~2mph in the 1/4 mile, 0 other changes
No doubt the DCT will shift faster, but in manual mode, it is still up to a person to command the shift. Any minuscule delay, or not at the optimal RPM will cost time. That is where the slush box could make up for some of that lost ground, as the ECU will execute absolute precise, optimal, and consistent shifts every time.
It will be interesting to see what shift strategy Ford offers if you leave it in fully auto mode and let it do the shifting for you. If they offer some race auto race mode, that would likely negate the above.
It will be interesting to see what shift strategy Ford offers if you leave it in fully auto mode and let it do the shifting for you. If they offer some race auto race mode, that would likely negate the above.
I’d expect the DCT to have an auto drag feature and give a perfect series of optimal shifts for quarter mile performance.
It’s their launch control I’ve never been impressed with.
If Ford is smart they will have calibrated the drag mode to give launch control optimized for drag radial track launches followed by perfect auto shifts. We shall see.
-J
It’s their launch control I’ve never been impressed with.
If Ford is smart they will have calibrated the drag mode to give launch control optimized for drag radial track launches followed by perfect auto shifts. We shall see.
-J
They put a drag mode on the damn gt with am auto. Can't see why the gt500 doesn't get one.
There are times it would be better, especially depending on powerband, that shifting earlier would help. But thats a different topic. the time it takes to shift is still the benefit, regardless of at what rpm, that doeasnt change
Exactly my point, plus we know this new 500 has a drag mode. I expect the shits to be on point. Now, the launch control?
-J
15" brake conversion, hoosier bias ply's, 5k rpm and have at it lol
That power band is off in the pic. The car will have more like this powerband. Ie climbing at 7500rpm. This iirc is a supercharged gt350.
Can you rerun the simulation with 8200rpm shifts and 760hp from 7500-8000rpm and 8k rpm shift? I honestly think the car will make 790-800hp at 8200rpm.
I’d guess 10.5@140 is possible in a perfect condition with 1.75 60ft
Throw a tire and race gas, might have a 9.75@144+ in perfect conditions.
The average gt500 time will be 10.8-11.5@ 130+ imo. Tracks altitude how fat the driver is etc all matter even in a dct car with decent traction.
You really think this car has 140 in it stock? At 4K+ lbs, I just have a hard time seeing that happen. That’s hyper car territory, and would smoke their own $500K GT.
I could see 135 under perfect conditions
In the conditions the demon went 9.65@140, yes. In average conditions 130-135.
The night/track the demon went 9.65@140, i’d Imagine a 2019 5.0 gt 10a could have gone 11.50@123 to give an idea of how opportune it was.
Iirc mid 50° range, sticky sub sea level track, lots of prep, etc.
I think 10.75@137 will be common enough to say it’s a solid near hero run.
I think 10.5@140 will be the eventual hero run. Iirc zr1 went 10.2@136 but that’s a lot of aero and an 8a.
The non carbon aero gt500’s will trap probably 3-5mph higher than the aero pack ones imo.
Big reason being I think the 760 is a soft rating much like the 2013 gt500’s 662 or the 03’s 390.
Demons claim 840 and make 760whp
I think the fords will follow in the bullitt, gt, and gt350’s footsteps of 10-12% drivetrain loss tops.
480hp Bullitts are making 435-450whp.
526hp gt350’s are making 460-485whp.
460hp 18+ 5.0 10a are making 415whp
460hp 18+ 5.0 6m are making 430whp.
I’m thinking:
760hp 20 gt500 will make 720whp.
•12psi 2.65 TVS and 9.5/1 5.2L with 8k rpm is well beyond a 760hp combo. 7psi voodoo 5.2’s albeit 12/1 iirc are making 750whp. 7 vs 12psi is much more drastic than 9.5 vs 12/1 compression.
•dct’s don’t sap up hp like auto’s do. There’s no where near the thermal loss or fluid exchange issues like an auto.
•The dct drivetrain in a gt500 could be about 40tq/55hp to fully turn 8k rpm maybe more since its also spinning some heavy brakes. An a8 auto drivetrain probably needs 70tq/85hp to fully spin to 7k rpm.
I don’t personally buy the % loss because the driven parts don’t get heavier or harder to turn as you increase hp. If they did, going up 1psi of boost at a time wouldn’t be as linear to calculate whp with. Also why are 500hp cars with manuals seemingly only losing about 30-40hp just like 300-400hp cars with similar manuals did... 2017 5.0’s have basically the same drivetrain loss as 2018’s. The engines are obviously slightly under rated in both applications by 15-20hp, but additionally, the trans, driveshaft, diff, wheels and tires are close to the same. Same goes for a 2010 4.6 mustang gt manual making 275whp on a 315hp rating. It takes torque to spin that stuff. It doesn’t magically take additional torque to spin that stuff or translate a higher hp cars power to the road. These drive trains aren’t sloppy either to where power may be escaping do to poor reinforcement of hard parts or insufficient clutches etc.
Put this dct in a demon and I bet it runs 9.25@145+ Halo run.
I think the absolutely fastest gt500 scenario would be a carbon fiber wheel setup on a base aero car but that’s not worth the $18k. Buy some $5-6k very light after market wheels and be done with it instead
Thing about spinning to 8k rpm is yes you have to spin a flywheel and clutch faster, but the engine is also more accurate and efficient at scavenging and clearing itself out up there as well. Engines are the least efficient at low to mid rpm for power production. Half the time the cycles are incomplete by some percent and the fuel doesn’t even fully burn.
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@Klaus i saw you are on the challenger hellcat forum.
What’s your take on my assumptions one post up? I’m honestly just speculating
What’s your take on my assumptions one post up? I’m honestly just speculating
Ill redo it, but i found a modest 5.0 660hp 2650 s/c dyno to reference for that. I didnt want to use a 5.2 fpc due to cr and rpms, it was hard to find one with readable rpm points. Ill run it to stock 7500 1st, then up the rpms
Ill update wih your graph later and see what we get
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Hey man. Agree with your view of 720whp. Your assumptions seem reasonable. I think your view on time/trap might be a bit conservative even. I think HC are dynoing ~620whp through the 8 speed and <11 capable if they hook up. The GT500 will be lighter and the power curve will be back ended relative to the HC which will be a big help in this case. 140 trap may be a touch fast but I think 10.5 will be very doable in the right hands. Total speculation but it will be closer to the ZR1 than people think.
All good point, just think we might be a little over zealous of the performance capabilities of this thing, that it will never be able to live up to. 140 just feels a little optimistic to me.
The '13/'14 GT500 beat(s) the '05/'06 GT in every performance metric, save for maybe braking. Even though all the owner deliveries aren't complete, the new GT is an "old" car dating back to 2015. The new GT500 might very well be able to beat it on some tracks and in some performance metrics.
I had that argument here some years ago. The "logic" then was that with the added HP/TRQ, the drivetrain parts produced more heat and resistance. But, yeah, I'm with you there in not believing drivetrain loss is linear like that. I believe there's a certain amount of loss by the parts and that's it. I don't believe adding power adds drivetrain losses.
I hear what you're saying, but the mid '00 GT was way out of production by the time trinity 500 came around, so I am not sure that is the best comparison. At least this time around, both are in production at the same time. Even though they are aimed at vastly different buyers, it just doesn't seem like Ford would want a far lesser model to outperform their halo vehicle.
Who knows, maybe they don't give a rip.
Likely never know as nobody is willing to offer up a GT for real data including Ford. Pretty lame honestly.
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