What is going on with traction at full throttle?

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Started autocrossing my Si with TSP Stage 1 tune, max boost mode., Bridgestone S04 pole position tires. At full throttle, in 1st or 2nd there is a momentary pulsing, lasting a second or two, like the opposite of ABS action, but slower in frequency. Traction control is off with light and blinking light on.

What is going on? Is this traction control, limited slip differential, clutch, some kind of tire slide-grip cycle, suspension? Anyone experience this or know what the cause is?
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Need more description but I would wager clutch slip especially if its wot from below 3k when it occurs. Hondata or ktuner?
 
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Need more description but I would wager clutch slip especially if its wot from below 3k when it occurs. Hondata or ktuner?
Thanks for the reply. I use ktuner. I think it may occur just when I floor it off the line, or out of a really tight turn in 2nd gear so it may be below 3k. Never happened at a track day when revs were probably always higher and no standing starts.
 

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Thanks for the reply. I use ktuner. I think it may occur just when I floor it off the line, or out of a really tight turn in 2nd gear so it may be below 3k. Never happened at a track day when revs were probably always higher and no standing starts.
One other possibility is your feeling the ECU making adjustments. When I first flash mine it's a little jumpy bringing power in and out at a cyclic rate until it's all learned in to the torque commands. Smooths out with some semi aggressive miles/ key cycles.

Are you flashing the car for or around each autocross?
 

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I would wager what you are feeling is the LSD.
Does this occur when you are at full lock or close to it?
I manage to activate the LSD just about every time I leave my garage, making a sharp right turn to get out.
 


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One other possibility is your feeling the ECU making adjustments. When I first flash mine it's a little jumpy bringing power in and out at a cyclic rate until it's all learned in to the torque commands. Smooths out with some semi aggressive miles/ key cycles.

Are you flashing the car for or around each autocross?
I had re-flashed after service a couple of weeks before the autocross, but didn't really push the car until the autocross. In my experience a slipping clutch feels more like nothing happens when you give it gas, not this jerking acceleration I am trying to describe. But then I've only experience old worn-out clutches slipping, not new inadequate clutch slippage.
 
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I would wager what you are feeling is the LSD.
Does this occur when you are at full lock or close to it?
I manage to activate the LSD just about every time I leave my garage, making a sharp right turn to get out.
It happens when I'm driving in a straight line, but the pavement was pretty wet sometimes at the autocross, even pouring rain at times, on an old airfield, uneven pavement.
 

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It happens when I'm driving in a straight line, but the pavement was pretty wet sometimes at the autocross, even pouring rain at times, on an old airfield, uneven pavement.
Wheel hop?
 
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A follow up on the resolution of this issue, after another day of autocross. It was wheel hop. It felt like the car was shaking itself to pieces on full throttle launches/ acceleration. Installing the stiffer rear motor mount completely solved the problem. Side effect is more felt engine vibration and sound at all times. But I am happy with the modification overall. It feels like the power that was going into shaking the car is now moving the car forward more efficiently. Similar to pedaling a high-end bicycle with a stiff frame,
 


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A follow up on the resolution of this issue, after another day of autocross. It was wheel hop. It felt like the car was shaking itself to pieces on full throttle launches/ acceleration. Installing the stiffer rear motor mount completely solved the problem. Side effect is more felt engine vibration and sound at all times. But I am happy with the modification overall. It feels like the power that was going into shaking the car is now moving the car forward more efficiently. Similar to pedaling a high-end bicycle with a stiff frame,
Did you order the motor mount yet?
 
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The car feels quite different. You can feel more of the engine vibrations. These vibrations also make noise since the engine is more tightly connected to the rest of the car, which vibrates and makes sounds, like a speaker. I like the way it feels. I like the sounds.

It encourages you to be more precise with rev matching when shifting, because there is an unpleasant feel and lurching if you don't.
I was riding with my ex-wife and she commented "you better learn how to use a manual transmission again." (She didn't need to say that.) But anyway, I've had to pay more attention to the clutch going into 1st and 2nd, which is a good thing.
 

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If you didn't do the pedal dance to completely turn off your assists, traction control is never turned off completely, it just allows for more wheel spin but on pavement it will still react quite fast. That button is made for insance where snow is involved.
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