Lingenfelter 2-Step Launch Control Installed.
05-14-2009, 01:06 PM
#1
Le Mans Master
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Location: Greater Detroit Metro MI, when I'm not travelling.
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Lingenfelter 2-Step Launch Control Installed.
I used to have Launch Control (and Flat Foot Shifting / No Lift Shift) on my Subaru STI via an ECU reprogram and it was awesome; I would hold the gas to the floor and bounce a secondary rev limiter which would actually spool the turbo from a standstill. When I found out that Lingenfelter makes something similar for the C6, I just had to give it a try...
Well here it is
:
The device is that small orange box that is currently velcroed on the side of my fender. There are 2 adjustments; RPM X 1000 and RPM x 100. Those two allow me to dial in the exact RPM I want to launch at. The orange plug is for a MAP sensor input which would allow Boost based ignition timing retard via the other two pots; I of course don't need that since my timing is tuned properly via the ECU. Those pots can be used to retard ignition timing via a trigger signal for things such as Nitrous injection, or perhaps something more clever, such as using a flow switch to command ignition timing retard should methanol injection fail in a car equipped with it. I am not using any of that.
The unit intercepts the factory coil packs with supplied plugs and is a true plug-and-play device; even the power for the unit comes from the coil pack plugs:
I routed all the wires along the fuel rail together with the factory fuel injector wires for a clean install. The trigger wire goes into the passenger side of the car without drilling any holes:
For triggering, I am using a Bosch automotive relay spliced into the factory clutch position switch; that relay switches 12 volts from the clutch pedal switch into the +12V trigger line of the launch control unit. I put a switch in line with that so I can turn the unit off for daily drivin.
Operation:
With the switch "ON" I push the clutch down and the car holds the exact RPM dialled into the unit, even at full throttle. Because I can hold full throttle, the supercharger bypass valve closes, pressurizing the intake manifold. At my currently selected 2300RPM, my blower makes 2PSI, and there are 380 foot pounds of torque available at the wheels. The moment the clutch comes off the floor, the ECU regains control over the rev limiter and the car behaves normally.
Because ignition is being cut anywhere after 2300RPMs with the clutch down, I can shift with the throttle buried to the floor; this makes the blow off valve never open between shifts, maintaining the intake manifold pressurized; boost is never vented so the infinitesimally small time delay between the blow off valve closing and the car coming back onto boost is eliminated. This is a big advantage on a turbo car that loses spool on shifts, but I am not convinced it helps on a S/C car.
Ultimately this unit allows me to launch at the same RPM every time, helping consistency.
WARNINGS:
This is ignition cut, not fuel cut; the injectors continue to spray raw fuel into the engine and that makes its way to the exhaust. On a catless car this means fireballs and backfires, but on a catted car like mine it means destroyed catalytic converters if I stay on it long enough. This is a risk I am willing to take because I never plan to stay on it for over a second.
Other than that, this unit allows launches to happen from a lower RPM, so you should (at least in theory) be less likely to break something.
RESULTS:
Well it definitely works in that the car holds and launches from the same RPM time after time. Unfortunately clutch issues currently prevent me from getting a proper pass though (when I launch, the pedal stays on the floor). I will try and post some videos of it in action later on, and will have some drag strip results once I get a new clutch in.
Well here it is
:The device is that small orange box that is currently velcroed on the side of my fender. There are 2 adjustments; RPM X 1000 and RPM x 100. Those two allow me to dial in the exact RPM I want to launch at. The orange plug is for a MAP sensor input which would allow Boost based ignition timing retard via the other two pots; I of course don't need that since my timing is tuned properly via the ECU. Those pots can be used to retard ignition timing via a trigger signal for things such as Nitrous injection, or perhaps something more clever, such as using a flow switch to command ignition timing retard should methanol injection fail in a car equipped with it. I am not using any of that.
The unit intercepts the factory coil packs with supplied plugs and is a true plug-and-play device; even the power for the unit comes from the coil pack plugs:
I routed all the wires along the fuel rail together with the factory fuel injector wires for a clean install. The trigger wire goes into the passenger side of the car without drilling any holes:
For triggering, I am using a Bosch automotive relay spliced into the factory clutch position switch; that relay switches 12 volts from the clutch pedal switch into the +12V trigger line of the launch control unit. I put a switch in line with that so I can turn the unit off for daily drivin.
Operation:
With the switch "ON" I push the clutch down and the car holds the exact RPM dialled into the unit, even at full throttle. Because I can hold full throttle, the supercharger bypass valve closes, pressurizing the intake manifold. At my currently selected 2300RPM, my blower makes 2PSI, and there are 380 foot pounds of torque available at the wheels. The moment the clutch comes off the floor, the ECU regains control over the rev limiter and the car behaves normally.
Because ignition is being cut anywhere after 2300RPMs with the clutch down, I can shift with the throttle buried to the floor; this makes the blow off valve never open between shifts, maintaining the intake manifold pressurized; boost is never vented so the infinitesimally small time delay between the blow off valve closing and the car coming back onto boost is eliminated. This is a big advantage on a turbo car that loses spool on shifts, but I am not convinced it helps on a S/C car.
Ultimately this unit allows me to launch at the same RPM every time, helping consistency.
WARNINGS:
This is ignition cut, not fuel cut; the injectors continue to spray raw fuel into the engine and that makes its way to the exhaust. On a catless car this means fireballs and backfires, but on a catted car like mine it means destroyed catalytic converters if I stay on it long enough. This is a risk I am willing to take because I never plan to stay on it for over a second.
Other than that, this unit allows launches to happen from a lower RPM, so you should (at least in theory) be less likely to break something.
RESULTS:
Well it definitely works in that the car holds and launches from the same RPM time after time. Unfortunately clutch issues currently prevent me from getting a proper pass though (when I launch, the pedal stays on the floor). I will try and post some videos of it in action later on, and will have some drag strip results once I get a new clutch in.
05-14-2009, 02:05 PM
#2
I've got mine for sale (it's as good as new - a month old) for $150............. This piece works great!
Install looks great other than you need to run those wires through the firewall! Running them along the door jam is really ghetto!
Install looks great other than you need to run those wires through the firewall! Running them along the door jam is really ghetto!
05-14-2009, 02:08 PM
#3
Le Mans Master
Thread Starter
Member Since: Oct 2007
Location: Greater Detroit Metro MI, when I'm not travelling.
Posts: 6,149
Likes: 0
Received 10 Likes
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10 Posts
Hey, I was in a hurry!!!Is there a spot on the firewall where I can run the wires though, or do I have to drill a hole?
05-14-2009, 03:03 PM
#4
Team Owner
those two steps seem to work well in most applications too.
05-14-2009, 03:41 PM
#5
Is there a spot on the firewall where I can run the wires though, or do I have to drill a hole?
The hole in the firewall is just above the PCM in the passenger foot/kick panel area. There is a rubber grommet that the wiring harness passes through. You have several options (cut the grommet, run wires through the grommet as it is, route wires around the grommet, etc...) with the grommet. Pick your option, then replace the grommet in the firewall and happy driving!
01-24-2010, 06:34 AM
#10
Tech Contributor
Here's another thread with drag strip video of the 2 step...it results in some really good times, 1.4 60's! However, Isaiah48 broke his rear on his first try with the 2 step.
http://forums.corvetteforum.com/c6-t...ay-at-mir.html
http://forums.corvetteforum.com/c6-t...ay-at-mir.html
