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Discussion Starter #1
So my mom's been complaining about her SC, she doesnt like how it "takes to long to go fast" (compared to her LX470 which she says "goes zoom right away"), after she described what she meant, which was there seems to be a 3 second delay from when u floor the pedal to when the car downshifts and starts accelerating.

i decided to see for myself, i drove the SC (with power button on) and it really did seem to just be sluggish and there was a definite delay.

i talked to her about aftermarket upgrades for it.

so my question is would a valve body upgrade really help out the reaction time of the SC and if so where should i look into getting one and getting one installed?
 

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Grt06 said:
So my mom's been complaining about her SC, she doesnt like how it "takes to long to go fast" (compared to her LX470 which she says "goes zoom right away"), after she described what she meant, which was there seems to be a 3 second delay from when u floor the pedal to when the car downshifts and starts accelerating.

i decided to see for myself, i drove the SC (with power button on) and it really did seem to just be sluggish and there was a definite delay.

i talked to her about aftermarket upgrades for it.

so my question is would a valve body upgrade really help out the reaction time of the SC and if so where should i look into getting one and getting one installed?
A VB upgrade can be done in the latest model SC430... it uses the exact same transmission (A650E) as the e-shift IS300.

Prior Models... I'm not sure.

Where are you located?
 

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Discussion Starter #6
haha yeah cdd is only manual, and the SC430 is only auto, and correct me if im wrong but there is only one model type for the sc430 the older models would be sc400's

and das im located in the middle of MD so i got SRT and Turboeast like 40 minutes away
 

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dasgalloway said:
You mean CDD mod?
no the tdd mod lol....the one that puts that little spacer on the throttle cable for quicker response. I know all our cars will feel that since that little mush on the gas pedal will be gone.

Or just get her an after market intake....it might put a placebo effect on her since the engine sounds more alive lol although intake does help a little.
 

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Is her car regularly maintained? There is no way an SC430 should feel slow.
 

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Discussion Starter #9
yes the car is regularly maintained. only 10-15k miles on it. and its not the throttle that makes it feel slow its def the transmission because it takes forever to downshift and start accelerating once you floor it.

so das r u sure its the same tranny, and if so would the valve-body upgrade help the problem that im describing?
 

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Pull the negative terminal from the battery for 20 mins to reset. Let the car re-learn your mom's driving patterns. Tell her to drive the car more aggressively for the next while. I've done this on a few Toyotas with auto-trannies and it solves this exact problem.
 
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Discussion Starter #11
thanks platinum
 

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Grt06 said:
yes the car is regularly maintained. only 10-15k miles on it. and its not the throttle that makes it feel slow its def the transmission because it takes forever to downshift and start accelerating once you floor it.

so das r u sure its the same tranny, and if so would the valve-body upgrade help the problem that im describing?

Yes, it is the same tranny... I have the OEM service manual.

The VB will definitely make it shift faster.

Is she putting premium in it?
 

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might want to ask some opinions on club lexus too. Not sure how many experts on the SC we have here (other than das b/c he's da man).
 

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acumenhokie said:
might want to ask some opinions on club lexus too. Not sure how many experts on the SC we have here (other than das b/c he's da man).

Not an SC expert, but I do know the tranny since it's the same as the E-shift IS300's
 

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Dude i think it's TCS mod : throttle cable spacer mod.

You could do that and try tightening the throttle cable but put a washer b/t the pedal and the floor so it's not stretching the cable.

I guess if u don't want the delay you could use the shift buttons to knock it down to 2 or whatever you need.

Hope that helps.

edit: could engine or tranny oil be to blame?
 

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Platinum288 said:
Pull the negative terminal from the battery for 20 mins to reset. Let the car re-learn your mom's driving patterns. Tell her to drive the car more aggressively for the next while. I've done this on a few Toyotas with auto-trannies and it solves this exact problem.

please prove this. where in the ecu progaming is it able to learn a driver's driving pattern??
 

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goohead said:
please prove this. where in the ecu progaming is it able to learn a driver's driving pattern??

In lexus marketing materials?

I have always wanted to record what the ECU is doing to "learn" these patterns, however...
 

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goohead said:
please prove this. where in the ecu progaming is it able to learn a driver's driving pattern??
Fuzzy logic has been used in automobile technology for years from automatic trannies to ABS brake systems to vehicle stability. Adaptive algorithms take inputs from various sources and use them to adjust weights on the coefficients used in calculating particular outputs. What it is trying to do is effectively predict a pattern and react to that pattern. If a neural network system is exposed to enough input over time, it will be able to learn and adapt to your patterns. If you pull the power to reset the ECU, all the learned weightings will disappear and revert back to baseline. The learning process is started all over again.
 

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Platinum288 said:
Fuzzy logic has been used in automobile technology for years from automatic trannies to ABS brake systems to vehicle stability. Adaptive algorithms take inputs from various sources and use them to adjust weights on the coefficients used in calculating particular outputs. What it is trying to do is effectively predict a pattern and react to that pattern. If a neural network system is exposed to enough input over time, it will be able to learn and adapt to your patterns. If you pull the power to reset the ECU, all the learned weightings will disappear and revert back to baseline. The learning process is started all over again.

reason why i asked i tried this one my maxima multiple times and never seen any diff... any link to where you got the info from?
 

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goohead said:
reason why i asked i tried this one my maxima multiple times and never seen any diff... any link to where you got the info from?
I know the theory behind the application and I've tried this method on Hondas and Toyotas with success. Toyota ECT-i (intelligence) trannies use adaptive fuzzy logic algorithms. The adjusted coefficients are stored in volitile memory and will be wiped when there is no power to maintain the adjusted values. That's just how the system works. If you google it, you'll find lots of information regarding fuzzy logic and adaptive learning applied in Toyota trannies.

If you notice no difference on your Maxima, perhaps you don't have an adaptive learning auto tranny or a tranny with multiple shift maps. If you are having issues with your Maxima, I would suggest visiting a Nissan forum for further advice.
 
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