Launch Control- Initial trials

My Octavia ALH manual has been re-mapped by myself. I saw a 1.2 second reduction in 1/4 mile times, and about 1 sec drop in 0-60mph.

However, my 60ft times didnt really improve.

I reckon it was a combination of the car being mapped for 200ft/lb from 1500rpm, and really crap tyres on the front.

As I read more into the mapping software, it became apparent that you could create a launch control map- essentially limiting the level of fuelling available at a standstill, then phasing in more as the car got underway.

I had a try at doing it tonight, and it makes a helluva difference: launches are consistent with minimal wheelspin.

Feels a bit odd to go foot flat to the floor with the clutch down, and only have it rev to 1600ish

the real trial will be in the rain!

Stock map (I.E. no Launch Control)


Modified map

That's pretty awesome man.
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Yes, my TDTuning files from vwmikel have that, though mine is set to 4000 limit. Any lower and my big ass turbo wont stay spooled with the slicks.

dremd said:

That's pretty awesome man.
Subscribed

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Cheers, yeah I think it may need a bit more work to get it spot on but its a big improvement!

oldpoopie said:

Yes, my TDTuning files from vwmikel have that, though mine is set to 4000 limit. Any lower and my big ass turbo wont stay spooled with the slicks.

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I only have a stock turbo fitted, so can get away with 1800rpm or so. At that point it'll pull cleanly for a bit then some wheelslip.

I may consider tweaking it so it holds back for a bit longer.

Is this the same as the 'popcorn limiter'?

numbnuts said:

Is this the same as the 'popcorn limiter'?

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I have no idea what that is?

this holds the engine at fixed revs until clutch is taken up and car starts moving.

once moving it progressively increases fuelling in line with roadspeed and rpm

essentially supplying just enough power for a little wheelslip.

I have "launch control" on my tune (just holds 2100rpm until the car starts moving) and I view it just as a fun factor. Does it make my autocross starts faster? Idunno, but it sure is fun to see a dieselcar at the start line going bruuuuuuuu-bum-bum-bum-bum-bum! I've found 2100rpm to be the sweet spot for my car's power level in dry weather. There is no torque limiting on mine as speed increases so it wouldn't work in the rain, my tires would just spin.

I even had Mark make sure the revs bounced!

I think the "popcorn" limiter is referring to that "bum-bum-bum" noise that I've tried mimicking by typing out.

Joester said:

I have "launch control" on my tune (just holds 2100rpm until the car starts moving) and I view it just as a fun factor. Does it make my autocross starts faster? Idunno, but it sure is fun to see a dieselcar at the start line going bruuuuuuuu-bum-bum-bum-bum-bum! I've found 2100rpm to be the sweet spot for my car's power level in dry weather. There is no torque limiting on mine as speed increases so it wouldn't work in the rain, my tires would just spin.
I even had Mark make sure the revs bounced!
I think the "popcorn" limiter is referring to that "bum-bum-bum" noise that I've tried mimicking by typing out.

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cool

my lc is set at 1800rpm just now.works in the dry a treat-still lots of spin in the wet.

Reckon new tyres may be sensible, but that costs money

WoodieGuthrie said:

cool
my lc is set at 1800rpm just now.works in the dry a treat-still lots of spin in the wet.
Reckon new tyres may be sensible, but that costs money

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What tires do you have? I have 225cm wide 280 treadwear summer tires and it sticks pretty well. Heavy setup though.

Joester said:

What tires do you have? I have 225cm wide 280 treadwear summer tires and it sticks pretty well. Heavy setup though.

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they are 195/65/15s of a budget make, apparently made of plastic..

For drag racing I'll be getting softer tyres I think

I have essentially a stock car with tune but have been playing with LC too... I had mine popcorn but doesn't build boost and seems kinda bad for the car so I went with about 2800rpm limit and builds about 8lbs but spins tires like crazy lol so I don't think I will be using it all that often

tromano32 said:

I have essentially a stock car with tune but have been playing with LC too... I had mine popcorn but doesn't build boost and seems kinda bad for the car so I went with about 2800rpm limit and builds about 8lbs but spins tires like crazy lol so I don't think I will be using it all that often

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my tune has full boost coming in about 2000rpm.

having LC at 1800rpm means it doesnt just boost like billio from the off

He means that revving without load he can make 8 psi. It doesn't matter if the tune asks for more, without load you cannot build the boost.

BTW, that pop pop limiter reduces the amount of boost you can build.
Make it smooth drop like you see below and it won't pop pop.

I too did the speed limiting rpm through the range for 1st gear. Originally, I made it to slip 10% rpm, but sometimes it would cut power without wheelspin. The ecu sometimes seems not fast enough to react. So best to give a wider leeway.

robnitro said:

He means that revving without load he can make 8 psi. It doesn't matter if the tune asks for more, without load you cannot build the boost.

BTW, that pop pop limiter reduces the amount of boost you can build.
Make it smooth drop like you see below and it won't pop pop.

I too did the speed limiting rpm through the range for 1st gear. Originally, I made it to slip 10% rpm, but sometimes it would cut power without wheelspin. The ecu sometimes seems not fast enough to react. So best to give a wider leeway.

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thanks for that-will have a look tonight when I get in!

yes I meant no load 8psi... I like your LC map... kinda works like traction control a bit too when you slip in rain and snow?

Is this only available on the EDC15 / 2000+ ECUs?

-J

compu_85 said:

Is this only available on the EDC15 / 2000+ ECUs?

-J

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I honestly could not tell you- I'm new to this Tdi tuning malarky, and seem to have been lucky in the car I bought!

http://www.ecuconnections.com/forum/viewtopic.php?f=2&t=3312&start=575

"

Re: "Launch Control for EDC15 TDI's "

by sneikas » Thu May 14, 2015 3:21 am
2.5TDI v6 1998-2001 - possible (msa15)
2.5TDI v6 2001-2005 - not possible (edc15)
1.9TDI r4 1768-1999/05 - not possible (msa15)
1.9TDI r4 1999/05-till now - possible (edc15,16,17)"

This is great fun at junctions or coming onto roundabouts

I'm unsure whether it is worth having on every day- but it certainly helps in the wet in the lower gears with current tuning