Jerking at high speed

[piggybomb]

I have only been able to replicate this on the long straightway at my local track. I wasn't able to do it on the street (but I can try again). Luckily I have datalog from the track.

So I am WOT on the straight until I am in 4th gear at ~7k rpm, I then ease off throttle to maintain a speed before a high speed turn.
When I ease off throttle, the car starts to violently jerk.

I am trying to figure out if it is a problem with the tune or it is a TPS problem. This is a fairly newly built k24 frank motor so I'm not sure if the tune is fully dialed in. I have an Acuity TPS

I have calibrated the TPS on the Kpro.

Is it:
1. the car jerking, causing my foot to shake and causes the fluctuation in TPS?
2. the TPS is bad and is causing the jerking specifically around 20-40%?
3. the vibrations of a k24 with type s oil pump is causing too much vibration and messing with the sensors?

Could someone take a look at my data log and guess what is causing the jerking? The times to look at is 2:18, 4:08, 6:14, 8:19, and 9:59.

[Spunkster]

Without the calibration the datalog was made with it's hard to say what might be happening.

[piggybomb]

here's the calibration

[Spunkster]

Has it been properly tuned at part throttle?

With the ignition on, but not running, does it read smoothly when moving the throttle?

[piggybomb]

It was tuned by a professional, so I hope it is properly tuned at part throttle.

Here is a datalog of car not running, the throttle looks a lot smoother than when it was on the track.

[Spunkster]

It may be the engine mounts being too stiff and the TPS does not like that much vibration.

[piggybomb]

I have hasport 62a mounts. Not the stiffest but stiffer than OEM. Is this common with k24 builds with type s oil pump? Would a fluidampr harmonic balancer help prevent this?

Also, from the datalogs. Do you think my car is running too rich?

From the calibration, is tip in fuel too high?

[Spunkster]

You can try the balancer and see if it helps.

It does not appear to be running too rich or have any major tuning issues, but I am not a tuner and cannot spend several hours going over the datalog with a fine-tooth comb.