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M/T a bit frustrating

Litfuse

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I had the opportunity to drive a manual TJ and a manual JLR back to back several times. Around town, the TJ feels more zippy. I think it has to do with the lighter weight of the TJ and the mechanical throttle cable. It has instantaneous pull when you touch the throttle. Above 50mph, it falls pretty hard on its face.

I owned several TJs and I didn’t remember having such a heavy clutch pedal until I drove it after driving my JLR. It’s a leg workout!
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AnnDee4444

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I had the opportunity to drive a manual TJ and a manual JLR back to back several times. Around town, the TJ feels more zippy. I think it has to do with the lighter weight of the TJ and the mechanical throttle cable. It has instantaneous pull when you touch the throttle. Above 50mph, it falls pretty hard on its face.

I owned several TJs and I didn’t remember having such a heavy clutch pedal until I drove it after driving my JLR. It’s a leg workout!
Do you know what tire size & gear ratio the TJ was?

That's the downside to DBW: you are at the mercy of how the manufacturer programmed it. DBW can be just as responsive as a cable with the right tune though.
 

AnnDee4444

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Litfuse

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Do you know what tire size & gear ratio the TJ was?

That's the downside to DBW: you are at the mercy of how the manufacturer programmed it. DBW can be just as responsive as a cable with the right tune though.
The TJ had 3.73 gears and 30.5 inch tires.
 

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DanW

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I had the opportunity to drive a manual TJ and a manual JLR back to back several times. Around town, the TJ feels more zippy. I think it has to do with the lighter weight of the TJ and the mechanical throttle cable. It has instantaneous pull when you touch the throttle. Above 50mph, it falls pretty hard on its face.

I owned several TJs and I didn’t remember having such a heavy clutch pedal until I drove it after driving my JLR. It’s a leg workout!
I think you are onto something with the cable throttle. My JK sometimes has delay in the throttle by wire that really has a huge effect on driveability. My JL has much less of that, so I don't notice it. I'd bet if I drove a TJ or my old YJ, though, it would be very noticeable.
 

DanW

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Litfuse

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I think you are onto something with the cable throttle. My JK sometimes has delay in the throttle by wire that really has a huge effect on driveability. My JL has much less of that, so I don't notice it. I'd bet if I drove a TJ or my old YJ, though, it would be very noticeable.
I owned two JKs and I could not wait to throw a pedal commander on it when I bought them new. The throttle was so lazy. I do think FCA corrected this by a great deal with the JL. I never felt the JL needed a pedal commander.
 

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8flat

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The 3.6 actually has more low-end torque than the 4.0.
If you are interested, I graphed out what the road force would look like with a 4.0 in the JLR: https://www.jlwranglerforums.com/forum/threads/2-0-turbo-vs-pentastar-v6.22809/page-11#post-870456

Torque Output.webp
This just doesn't make sense. At idle, the 3.6 not only doesn't have any torque, it sounds like it's actually hard on it (lugging, etc). Those numbers are sourced from a 3.6 with an auto, I'm guessing at 1,000RPM it can post decent numbers due to the torque converter. I think if that same dyno run was made with a manual, and no clutch slippage, the 3.6 would post lower numbers at 1,000rpm.

And the numbers at idle would be horrid.

Just a guess. This is a car engine with no off-idle torque.
 

AnnDee4444

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This just doesn't make sense. At idle, the 3.6 not only doesn't have any torque, it sounds like it's actually hard on it (lugging, etc). Those numbers are sourced from a 3.6 with an auto, I'm guessing at 1,000RPM it can post decent numbers due to the torque converter. I think if that same dyno run was made with a manual, and no clutch slippage, the 3.6 would post lower numbers at 1,000rpm.

And the numbers at idle would be horrid.

Just a guess. This is a car engine with no off-idle torque.
The numbers I posted are peak (WOT) torque values at the crankshaft, without any drive-train loss. Manufactures do have different tunes for auto vs. manual, but I don't think that's what is going on here. I suspect that it's the part throttle response that is the issue. The 4.0 had great off-idle torque with only partial throttle input. I haven't driven a manual 3.6 JL, but I know that Jeep's DBW is tuned to be slightly 'muted' (probably for fuel economy reasons).

My other vehicle is a manual DBW with little low end torque, and after tuning the DBW curve drivability and slow speed control was greatly improved.
 

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“The Aisin D478 transmission is poorly matched to the 3.6-liter V-6, which suffers a low-end torque deficit“
They really picked the wrong engine for the 6MT. It would pair better with the 2.0.
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