XHP Issue - Help Needed

[N800MRG]

Hi guys,

I’ve had this issue ever since I flashed XHP on my car. But it’s got to the point where it’s really bugging me now.

Basically, when driving in comfort, which I do a lot of the time as my car is a daily driver, if I accelerate over 50% throttle the XHP Ignition Cut kicks in when the car upshifts. This is fine, it does the same in sport, but in comfort it makes the shifts ridiculously jerky/laggy and the car almost falls on its face for split second between shifts.

This doesn’t happen when driving in sport mode, or when driving in manual mode. Even when driving in manual mode, but still with comfort mode active it doesn’t do it. It’s only when in comfort + auto, and only when over 50% throttle so the Ignition Cuts are active.

Obviously the majority of the time if I want to accelerate hard I switch into sport mode, but for example when coming off a roundabout during my commute or when giving it a blast down the motorway it makes the shifts almost unbearable if I use over 50% throttle.

I have a JB4 fitted to the car as well, I initially thought it was the Auto Shift Boost Reduction feature on the JB4 messing with the Ignition Cut feature of XHP. But I have tried every setting from 0 through to 100 on the JB4 and it has no affect.

I contacted XHP regarding turning off the Ignition Cut in comfort mode but they informed me that it isn’t possible. So I am just looking to see if anyone else has issues with their XHP when I’m comfort mode or maybe it’s just my car?

Thanks in advance,
Marcus

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[Deathscythe]

I actually hat this exact same issue as well, exactly as you described it.

The only difference is that my car does not have the JB4.

I spent the last month adjusting all applicable settings to no avail. A few weeks ago I found some settings that seemed to help, but they really masked the issue rather than solving it.

Long story short:

I'm almost 100% sure that this IS in fact Ignition Cut shifting occurring. I drove hundreds of test miles and tried just about every safe configuration you could try.

After looking at the XHP documentation, I saw that the feature "Ignition Cut Shifting" was formerly "Soft Shifts in Sport Mode."

The note under the feature reads:

"This flash setting is obsolete and was replaced by the Ignition-Cut Shifting. If you do want to have soft shifts in sport mode, move the “rpm” and “Nm” sliders of the “Standard” and the “Fast” settings (if available) all the way to the right and save them.
This way, the car never uses “Ignition cut during shifting”. Then flash the desired stage. "

Reference:
https://rbttuning.atlassian.net/wik...eed+ZF+-+Flash+Settings#Ignition-Cut-Shifting

Knowing this, I figured I would perform an experiment.


For the Supra's ZF8 we have the ability to modify Ignition Cust Shifting for both Standard and Sport modes. So I figured I'd try to eliminate Ignition Cut Shifting from normal mode, but keep it in Sport mode.


As a result of the info above I made the following custom flash changes:

Ignition Cut Shifting - ON

• Standard - (sliders all the way to the right)
  • 8000rpm
  • 737 ft-lb
    
• Fast
  • 3750 rpm
  • 184 ft-lb

This resulted in completely smooth shifts in normal mode with no huge 2-3 gear upshift lag/ ignition cut.

Sport mode functions as it should and still performs ignition cut shifts when at the RPM listed.

Note:
When I tried moving the sport mode sliders all the way to the left for some reason, I lost all ignition cut shifting in Sport mode. The settings above are what worked for me and gave me an OEM like feel with all of the benefits of the XHP OTS maps and settings.

Hopefully this helps!