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Discussion Starter #1
How does MDX Sport Hybrid sustain high speed acceleration to 130mph and be faster than non-hybrid 3.5L SH-AWD if the battery is under discharged mode during constant acceleration?

I imagine under sustained acceleration, the battery charge will deplete (regenerate when the car is slowing/braking) so the car will on rely on its 3.0L 257HP while the non-hybrid has 290HP engine?



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The MDX Sport Hybrid is just fwd with 3.0L once you hit +80 mph (84 is exact mph I think). I didn't see any regen braking, charging of battery pack, or tq vectoring at +84 mph. I was in Sport mode, don't know if anything would change in Sport+ mode. Noticed the use of I.C.E. only when passing on 2 lane hwys and some interstates out west have posed speeds of 80 mph and I set the ACC to 85 mph.

My hybrid can go from 70-75 mph to 95-100 mph a lot quicker than my 11 MDX. My RLX Sport Hybrid can do +110 mph in the same 2 lane hwy passing maneuver. Both of my hybrids come in about the same curb weight (100lbs more for the MDX).
 

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This is a quote from Motor Trend. "Sport+ mode entertainingly keeps the electric motors on, providing full power during takeoff. Sport+ mode also adjusts throttle response and transmission shifts for maximum performance"
 

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Discussion Starter #5
The MDX Sport Hybrid is just fwd with 3.0L once you hit +80 mph (84 is exact mph I think). I didn't see any regen braking, charging of battery pack, or tq vectoring at +84 mph. I was in Sport mode, don't know if anything would change in Sport+ mode. Noticed the use of I.C.E. only when passing on 2 lane hwys and some interstates out west have posed speeds of 80 mph and I set the ACC to 85 mph.

My hybrid can go from 70-75 mph to 95-100 mph a lot quicker than my 11 MDX. My RLX Sport Hybrid can do +110 mph in the same 2 lane hwy passing maneuver. Both of my hybrids come in about the same curb weight (100lbs more for the MDX).
If it were true that above 84mph, the MDX hybrid relies on 3.0L engine (257HP) only, then it would have been slower above 84mph than '11 MDX SH-AWD with its 3.7L 300HP or '20 MDX SH-AWD. Since it is not the same , the electric motor must have been working synergistic .

But I wonder how since the battery without regen should have been depleted?

Did you notice whether the battery power level is low and whether the power distribution monitor show the battery providing power to the wheels at sustained 84+ mph?
 

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I keep my MDX in Sport mode and the battery pack range is usually between 1/3-2/3 for stop/go city or 80-85 mph hwy speeds. I've seen it below 1/3 only with city driving. Once I put it into Sport+, the battery pack is charged to 100% in 1-2 miles (along with downshift to lower gear and improved throttle response).

The power distribution monitor shows zero electric activity from the rear motors at +80 mph (power, tq vectoring, regen on/off brake pedal). The battery pack shows blue to the front wheels when providing power (green when regen or recharge from engine). I didn't see any blue from the battery at +80 mph; but, that just might mean battery power wasn't needed for my driving conditions. I don't think I've seen the Sport Hybrid run on front electric motor alone?

I know the front electric motor is inside the 7DCT; but, not 100% sure if the front electric motor is before or after the 7DCT? Maybe the improved acceleration might because of less drivetrain loss with the 7DCT and nothing between the electric motor and wheels?
 

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I got mine to 173 MPH by disconnecting the governing module and back looping the battery emulator. You must be doing something wrong.
 

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I keep my MDX in Sport mode and the battery pack range is usually between 1/3-2/3 for stop/go city or 80-85 mph hwy speeds. I've seen it below 1/3 only with city driving. Once I put it into Sport+, the battery pack is charged to 100% in 1-2 miles (along with downshift to lower gear and improved throttle response).

The power distribution monitor shows zero electric activity from the rear motors at +80 mph (power, tq vectoring, regen on/off brake pedal). The battery pack shows blue to the front wheels when providing power (green when regen or recharge from engine). I didn't see any blue from the battery at +80 mph; but, that just might mean battery power wasn't needed for my driving conditions. I don't think I've seen the Sport Hybrid run on front electric motor alone?

I know the front electric motor is inside the 7DCT; but, not 100% sure if the front electric motor is before or after the 7DCT? Maybe the improved acceleration might because of less drivetrain loss with the 7DCT and nothing between the electric motor and wheels?
Front motor is inside the DCT case and I don’t know where it connects. I’ve had both the hybrid and regular 3rd gen MDX. Regular MDX is stronger above 80 mph for sure.
 

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I know the electric motor is inside the 7DCT. I don't know if it is before or after the transmission (does it use the 7DCT). I don't think it is common to add a transmission to electric motors before the wheels because of the longer and linear instant tq starting from 0 rpms. I've noticed my hybrid idle speed is around 900-1000 rpms compared to around 200 rpm lower for my 11 MDX.

The Acura motors does show rpm ranges of:

Front Drive Motor Power (hp @ rpm) 47 @ 3000
Front Drive Motor Torque (lb-ft @ rpm) 109 @ 500-2000
Dual Rear Motors Power (hp @ rpm) (36 + 36) @ 4000
Dual Rear Motors Torque (lb-ft @ rpm) (54 + 54) @ 0-2000

I don't know if those rpm ranges are converted for matching the I.C.E. engine rpms OR they spin independently from the I.C.E.? The electric motors could be spin at a much lower 500-2000 rpm for max tq; while, the I.C.E. is in +4500 rpm i-Vtec mode.

I'm thinking the electric motors do provide power up to 84 mph before the software shuts them off. Then the fwd+7DCT might produce less drivetrain loss compared to 3.5L+9AT+sh-awd drivetrain at +84 mph.
 

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Discussion Starter #12
I f just found out that the chart was based on simulation model (not true road test) so the 321HP Hybrid w/DCT gearing shows faster high speed acceleration compare to 290HP non-hybrid w/9 speed gearing.
In actual, as stated above the 321HP is available only under 84mph (up to the 11k RPM of the electric motor) so under 84mph, the hybird is faster.
After 84moh it will rely on just the 257HP so top speed is limited to 110moh, slower than the 290HP version which can get slightly over 120mph.
 

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Here's is Car & Driver's actual road test results for the Hybrid. Their test results show top speed (governor limited): 133 mph
C/D TEST RESULTS:
Zero to 60 mph: 5.7 sec
Zero to 100 mph: 15.5 sec
Zero to 130 mph: 32.1 sec
Rolling start, 5-60 mph: 6.1 sec
Top gear, 30-50 mph: 3.6 sec
Top gear, 50-70 mph: 4.0 sec
Standing ¼-mile: 14.5 sec @ 97 mph
Top speed (governor limited): 133 mph
Braking, 70-0 mph: 188 ft
Roadholding, 300-ft-dia skidpad: 0.87 g
 
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