IS - 2nd Gen (2006-2013) Discussion about the 2006+ model IS models

Modifying the IS 350 computer to stop automatic down/up-shifting

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Old 04-05-08, 10:02 PM
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sammy5001
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Default Modifying the IS 350 computer to stop automatic down/up-shifting

With the IS 350 in manual mode, you can only set the "maximum" gear with the shift paddles and the computer will pick whatever gear that's lower than the max. This seems to me like a computer feature that can be hacked and changed easily.

Say I'm in 2nd gear and I upshift to 3rd, then it should immediately upshift to 3rd and stay in 3rd until I change it. (The current behavior is that it will upshift when it feels like it and even when I get to 3rd it will downshift whenever it feels like it).

You guys think this is possible and safe? This seems like a limitation put upon the IS 350 for no particular reason, other than to make the IS-F special in this aspect...I really don't see any physical reasons that are prevent this feature.
Old 04-05-08, 10:29 PM
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kt22cliff
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It's a slushbox. You should've get a manual gearbox car if you wanted that "behavior"

Originally Posted by sammy5001
With the IS 350 in manual mode, you can only set the "maximum" gear with the shift paddles and the computer will pick whatever gear that's lower than the max. This seems to me like a computer feature that can be hacked and changed easily.

Say I'm in 2nd gear and I upshift to 3rd, then it should immediately upshift to 3rd and stay in 3rd until I change it. (The current behavior is that it will upshift when it feels like it and even when I get to 3rd it will downshift whenever it feels like it).

You guys think this is possible and safe? This seems like a limitation put upon the IS 350 for no particular reason, other than to make the IS-F special in this aspect...I really don't see any physical reasons that are prevent this feature.
Old 04-05-08, 11:18 PM
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projectdna
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Originally Posted by kt22cliff
It's a slushbox. You should've get a manual gearbox car if you wanted that "behavior"
yah, but he'd be shorted 102 hp.

i think it is possible, to hack the computer to controll the up/downshifts. unfortunately that requires hacking the CPU, which no one to date has publicly admitted in being successful in doing so.
Old 04-05-08, 11:40 PM
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javyLSU
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Originally Posted by kt22cliff
It's a slushbox. You should've get a manual gearbox car if you wanted that "behavior"
Actually, as far as automatic transmissions go, you won't find any that are much better than the A760E. It's one of the quickest shifting transmissions on the market, and shifts more aggressively than any automatic I've ever used. I'm always amused when people think they can operate a transmission more effectively than a computer can when driving a car for performance.

Javier
Old 04-05-08, 11:50 PM
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kt22cliff
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Yeah in fact, when I put my car into 3rd, it shifts into 3rd right away and it doesn't auto-shift back up or down on its own unless I shift it myself. I think that's the exact behavior OP was/is looking for.

Originally Posted by javyLSU
Actually, as far as automatic transmissions go, you won't find any that are much better than the A760E. It's one of the quickest shifting transmissions on the market, and shifts more aggressively than any automatic I've ever used. I'm always amused when people think they can operate a transmission more effectively than a computer can when driving a car for performance.

Javier

Last edited by kt22cliff; 04-05-08 at 11:55 PM.
Old 04-06-08, 12:18 AM
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jackblack7
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Originally Posted by kt22cliff
Yeah in fact, when I put my car into 3rd, it shifts into 3rd right away and it doesn't auto-shift back up or down on its own unless I shift it myself. I think that's the exact behavior OP was/is looking for.
Are you sure you're looking at the right display? The large number shows what gear you've selected, but you have to use the multi-display to see what gear the car is actually in.
Old 04-06-08, 12:24 AM
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kt22cliff
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The car I'm talking about has manual gearbox

Originally Posted by jackblack7
Are you sure you're looking at the right display? The large number shows what gear you've selected, but you have to use the multi-display to see what gear the car is actually in.
Old 04-06-08, 02:40 AM
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ba-b4
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flip it into pwr mode. It'll hold your gears longer and shift down faster.
Old 04-06-08, 08:02 AM
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Bichon
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Originally Posted by sammy5001
With the IS 350 in manual mode, you can only set the "maximum" gear with the shift paddles and the computer will pick whatever gear that's lower than the max. This seems to me like a computer feature that can be hacked and changed easily.
Nothing easy about hacking Toyota/Lexus ECUs. The code and data are encrypted, and as far as I know, the scheme has not been broken.

Say I'm in 2nd gear and I upshift to 3rd, then it should immediately upshift to 3rd and stay in 3rd until I change it. (The current behavior is that it will upshift when it feels like it and even when I get to 3rd it will downshift whenever it feels like it).

You guys think this is possible and safe? This seems like a limitation put upon the IS 350 for no particular reason, other than to make the IS-F special in this aspect...I really don't see any physical reasons that are prevent this feature.
I wish it worked the way you describe. I find the current implementation so frustrating that I just leave it in Drive.

Originally Posted by javyLSU
I'm always amused when people think they can operate a transmission more effectively than a computer can when driving a car for performance.
For me, it's a not a question of effectiveness, it's a question of control. Pure driving enjoyment comes from having the car respond to my inputs, even if they are less than optimal. If I want the computer to operate the transmission, I'll put it in Drive. When I put it in sport mode however, I want it to go to the gear I select, when I select it, overriding my wishes only when following them would result in mechanical damage.
Old 04-06-08, 08:21 AM
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Witt
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I feel your pain. I switched from a Acura tl-s, 07 model to the is350. The automatic transmission in the IS is better in drive mode, but the manual mode in the TL worked just as it should. It stayed in any gearyou put it in. It wouldn't shift until you told it to. However, what was nice was that if you came to a stop, it would automatically put you in first gear. I was disappointed when I realized the manual mode in the IS didn't work the same.
Old 04-06-08, 10:25 AM
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Originally Posted by Witt
I feel your pain. I switched from a Acura tl-s, 07 model to the is350. The automatic transmission in the IS is better in drive mode, but the manual mode in the TL worked just as it should. It stayed in any gearyou put it in. It wouldn't shift until you told it to. However, what was nice was that if you came to a stop, it would automatically put you in first gear. I was disappointed when I realized the manual mode in the IS didn't work the same.
it does put u back in first gear after a stop...you have to change your display to see what gear your in... "disp" button on your wheel.

notice how smoothly you take off again after that stop---uh yeah your back in 1st you just dont see it on the number display - you see the last gear you chose
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