What cut patterns you config? Launch settings/2-step

Give input on tuning as well as any tips and tricks you may have. Also feel free to share base mapping files for various engine types.
Jon K
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What cut patterns you config? Launch settings/2-step

Post by Jon K »

I am playing with the pit speed limiter and was wondering what you guys are using as your cut patterns?

Also - I am using launch control "Limit RPM When Button Pressed Only" to build boost in neutral and while rolling. I am using the "Set Start RPM when Button First Pressed" so that I just rev or drive and hold the launch button to antilag. I do not build as much boost as I'd like and trying to figure out why.

My settings are:
Launch settings
Launch settings
I do not have "User Cut Patterns When Target RPM Exceeded"

I feel like it pulls timing nicely, but then seems to be cutting. I don't want to cut fuel because I want to build boost. Any thoughts on this setup? I haven't checked the logs yet, but audibly it sounds like it retards nicely, pops/bangs, I hear spool, but only get 2 - 3 PSI and then I get spaced out pops/bangs so it feels like it starts to hard cut but again, I cannot tell.

Anythoughts on this strategy?
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stevieturbo
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Re: What cut patterns you config? Launch settings/2-step

Post by stevieturbo »

The cut patterns allow you to choose cut fuel or spark, so maybe that might be a better route to take ?

Not sure of the launch strategies allow the user to choose what is being cut ?
Jon K
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Re: What cut patterns you config? Launch settings/2-step

Post by Jon K »

stevieturbo wrote:The cut patterns allow you to choose cut fuel or spark, so maybe that might be a better route to take ?

Not sure of the launch strategies allow the user to choose what is being cut ?
I do have that set:
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stevieturbo
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Re: What cut patterns you config? Launch settings/2-step

Post by stevieturbo »

Have you any logs of it sitting on the launch ? ie, does it record actual ign timing ? and what rpm is it actually holding and how much boost is it making ?
gnutz2
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Re: What cut patterns you config? Launch settings/2-step

Post by gnutz2 »

Retard before cut is the one you need to change to make lots of boost.

If i want a few psi on the start line I run low figures in that box, anything above 30 deg retard on my engine will make 1.5 bar boost.

I think it's degrees off your base timing, so if you had 30deg timing and put 50 in the box, the result would be - 20 deg of timing and lots of boost.

I noticed it says when car is stopped but mine seems to work when rolling!
Jon K
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Re: What cut patterns you config? Launch settings/2-step

Post by Jon K »

stevieturbo wrote:Have you any logs of it sitting on the launch ? ie, does it record actual ign timing ? and what rpm is it actually holding and how much boost is it making ?
Not yet - I will pull logs and see.
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Jon K
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Re: What cut patterns you config? Launch settings/2-step

Post by Jon K »

gnutz2 wrote:Retard before cut is the one you need to change to make lots of boost.

If i want a few psi on the start line I run low figures in that box, anything above 30 deg retard on my engine will make 1.5 bar boost.

I think it's degrees off your base timing, so if you had 30deg timing and put 50 in the box, the result would be - 20 deg of timing and lots of boost.

I noticed it says when car is stopped but mine seems to work when rolling!
Right so I think I'll be running like 12 - 16 degrees where the antilag/2-step should be happening at so -30 should be around -18 to -14 ish degrees. Maybe I should run a larger amount of pull?
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stevieturbo
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Re: What cut patterns you config? Launch settings/2-step

Post by stevieturbo »

Only way to know is to try, and worth keeping an eye on EGT's if you intend holding it on launch for more than a few seconds.


Although this is one for any new software/firmware. Proper rpm and boost targets for launch settings.

At the minute there's only rpm, and you have to play with it more to see what boost it may make.
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Re: What cut patterns you config? Launch settings/2-step

Post by Jon K »

Can anyone share their cut % or layout? Just interested more than anything.
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Re: What cut patterns you config? Launch settings/2-step

Post by stevieturbo »

It isnt really something I ever used much, as most of the time I used the DTA I had the blower, and with the old TT RV8 before that, I always launched manually. Never did get the launch working too well, although that was also on the P8 back then, not S-series
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