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Old Jan 26, 2012 | 09:35 AM
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Gear shift jerk on SST

hi..

This happens only a few times, I feel a big jerk when gear drop from D2 to D1 in low speed in Normal mode. Is it normal for the SST?
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Old Jan 26, 2012 | 09:57 AM
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Originally Posted by emperor496
hi..

This happens only a few times, I feel a big jerk when gear drop from D2 to D1 in low speed in Normal mode. Is it normal for the SST?
No, it's not normal.


Have you been tuned?

That exact issue cropped up in some prior beta revisions of the Ralliart GST Base Map. We tracked it down - the trail led back to a minor tuning change in the SST-Throttle-Voodoo-Requested-Torque-Guru-Meditation tables. Or something. Once the low-load, low-rpm cells were smoothed down towards stock values, it resolved the issue.

I reckon the ECU was getting confused, and tried to almost throttle-blip its way from 2 to 1 in Normal Auto mode. It had no place doing that in Normal, and got itself in a knot. Once fixed, there was no blipping, no clutch action, and all was smooth once again.

But... if you're on stock ECU, it's a "take it to the dealer" kind of thing.

Rich
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Old Jan 26, 2012 | 07:39 PM
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Originally Posted by richardjh
No, it's not normal.


Have you been tuned?

That exact issue cropped up in some prior beta revisions of the Ralliart GST Base Map. We tracked it down - the trail led back to a minor tuning change in the SST-Throttle-Voodoo-Requested-Torque-Guru-Meditation tables. Or something. Once the low-load, low-rpm cells were smoothed down towards stock values, it resolved the issue.

I reckon the ECU was getting confused, and tried to almost throttle-blip its way from 2 to 1 in Normal Auto mode. It had no place doing that in Normal, and got itself in a knot. Once fixed, there was no blipping, no clutch action, and all was smooth once again.

But... if you're on stock ECU, it's a "take it to the dealer" kind of thing.

Rich
I am on stock ECU. No plan to change to better ECU or tune right now. Will it damage the gear box or cluctch if it happens very often?

Will the jerk gone completely if I change the ECU or tune?
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Old Jan 26, 2012 | 08:11 PM
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xi
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Happened to me once or twice around 20000 miles ago, car still runs fine.
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Old Jan 26, 2012 | 08:44 PM
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Originally Posted by emperor496
I am on stock ECU. No plan to change to better ECU or tune right now. Will it damage the gear box or cluctch if it happens very often?
I'd raise it with the dealer... especially seeing as you're on stock tune.

Originally Posted by emperor496
Will the jerk gone completely if I change the ECU or tune?
Nope, I can't see how.

Rich
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Old Feb 4, 2012 | 12:10 AM
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I just watch the show Top Gear, they test the new lambo aventador.. and jeremy clarkson says that flappy paddle gearbox do jerk at low speed. Let say if we are trapped in traffic jam.. The lambo gearbox of cause better than evo sst, I think..

any comment??
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Old Feb 4, 2012 | 09:31 PM
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I'm at 20K now and never experienced it before? I don't think its normal anyway outta get that checked out bro.
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Old Feb 5, 2012 | 08:59 AM
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Originally Posted by daspasian
I'm at 20K now and never experienced it before? I don't think its normal anyway outta get that checked out bro.
will do..
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Old Feb 10, 2012 | 04:01 AM
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Any word on this?

My Ralliart when I had it did this as well and so does my X now occasionally.
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Old Feb 10, 2012 | 04:17 AM
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Originally Posted by Credz
Any word on this?

My Ralliart when I had it did this as well and so does my X now occasionally.
Your sig says Cobb Accessport... so your best bet is to raise it with them.

Rich
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Old Feb 10, 2012 | 06:36 AM
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Oh I didnt install that yet. It's still in the mail on the way. Haha.
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Old Feb 10, 2012 | 10:05 AM
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Your gonna feel the difference in the car
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Old Feb 12, 2012 | 12:21 AM
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the lambo trans isn't dual clutch either.
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Old Aug 3, 2016 | 10:09 PM
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Originally Posted by richardjh
No, it's not normal.


Have you been tuned?

That exact issue cropped up in some prior beta revisions of the Ralliart GST Base Map. We tracked it down - the trail led back to a minor tuning change in the SST-Throttle-Voodoo-Requested-Torque-Guru-Meditation tables. Or something. Once the low-load, low-rpm cells were smoothed down towards stock values, it resolved the issue.

I reckon the ECU was getting confused, and tried to almost throttle-blip its way from 2 to 1 in Normal Auto mode. It had no place doing that in Normal, and got itself in a knot. Once fixed, there was no blipping, no clutch action, and all was smooth once again.

But... if you're on stock ECU, it's a "take it to the dealer" kind of thing.

Rich
What did you do exactly ? I have this exact issue from 2nd to 1st on my 2012 MR, all stock SST tables. This clutch action is really annoying in normal, auto mode (especially for my girlfriend who don't drive in manual mode )

My thread about this issue is here: http://www.evoxforums.com/forums/sho...d.php?t=352041

Last edited by domyz; Aug 4, 2016 at 11:23 AM.
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Old Aug 9, 2016 | 08:08 AM
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Originally Posted by domyz
What did you do exactly ? I have this exact issue from 2nd to 1st on my 2012 MR, all stock SST tables. This clutch action is really annoying in normal, auto mode (especially for my girlfriend who don't drive in manual mode )

My thread about this issue is here: http://www.evoxforums.com/forums/sho...d.php?t=352041
Hi.

What did we do? We were revising the stock ECU SST-related maps, and making them not-stock.

If a stock-SST-map car in NORMAL AUTO is doing horrible clunky downshifts at low speed, it's not typical. And I don't reckon it's something that can really be "fixed" by editing ECU SST-related tables.

Rich
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