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Subaru bogging after launch

Launch Control

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I really need some input here as I am having an issue I can't seem to address.

Using a 2 step (fuel cut & -5* timing) to build boost and using a slipper clutch (issue occurs with or without it enabled)

The problem is that the car boggs once I achieve full traction. I have attached a log for reference. Launch is at 13:38.0 and boggs at 13:38.5-13:39.0

Boost pressure is good and any more RPM would result in lots of wheelspin, what do you suggest?

Attached Files

I can't read that file, but I do have a possible cause.

You aren't giving any info' on your setup, but what I think the problem will be is you have too big a turbo (hot side?) and/or a clutch incorrectly set up for your application.

When the clutch engages fully, it will pull the rpm down a little and that may bring it down, momentarily, to under the point where it is making full boost - almost immediately it's picking up rpm again to the point it is fully on boost.

As you have the luxury of a slipper clutch, I would start by adjusting it to 'lock up' a little higher in the engine's rpm range, and seeing what that does. If it works, as I expect, you may find you're able to add rpm and/or boost to the 2 step, and repeat.

Thanks for the response. I Changed the file to Excel.

Maybe the clutch is the issue as the turbo seems to be holding the boost just fine, however, as suggested, I will try a different RPM range

As far as the setup:

Engine: 2.0 EJ207

Turbo: TD05H-20G 10cm

Drivetrain: Stock 4WD

Tyres: Toyo Proxes R1R

That's better, thank you.

Yup, I see it is holding pressure, and the vehicle seems to be moving quite smartly off the line.

Could it be there is more of an impression of 'bogging' because of the rpm being pulled down slightly as the clutch bites, rather than a true bog?

If you can, try increasing the Hz for the speed logging, it may help to identify the apparent bog.

It is evident it's bogging. As soon as the car starts going the RPMs go from the LC 5500RPM to about 4200RPM.

You need to raise your RPM limiter or work on your LC to build more boost off the launch.

I would start with more RPM.

I thought would be to adjust the clutch to give a little more slip

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