2-step launch control

[Disturbed1]

hey guys im playing around with the two stepper feature of my ems ecu atm and im trying to work out if its a fuel cut style limiter or an ignition cut like those bee*R limiters that backfire and pop flames etc etc..

with a 3500 rpm limiter is mates 3 psi boost
and at 4000 rpm it makes 5 psi

when it sits on the limites it just bounces off it ever so quietly and shows mega lean mixtures as if its just cutting fuel... would u expect fuel cut to still generate boost in neutral???

[lojik]

I've taken this from the EMS 8860 manual. Fuel Cut.

"
2-step rpm limiter
This mode will enable the "Rpm Limit" field. In one switch position,
the Ecu will engage the Soft RPM limit to the value selected in the
field.
In the other switch position, the Ecu reverts back to the normal RPM
limits set in the main setup page.

This mode gives the user an extra stall Rpm limit.

Soft Rev Limit
The Ecu has a Rpm Limiter that can be adjusted from 0 to 32000 RPM

If you wish to use this option, set to the required rpm limit and press the enter button.

The rpm limiter cuts the fuel out on every second engine cycle e.g. the engine will be
injected with the correct amount of fuel for one cycle and no fuel for the next cycle, in turn
not running the engine lean at any stage.

To disable the Soft Rpm Limiter set it to 0 RPM.
"

[dori dori]

Haltech E11 FTW!

I have just set up my launch control with the Haltech guys and it holds 14psi rock solid.

It takes an input from the speed sensor to arm the system, i.e less than 12km/h the system is armed. More and the system disarms. Floor the throttle, revs reach 4000rpm and the launch control arms. It injects 15% more fuel across all cylinders and retards timing -17 degrees. When you're ready pop the clutch and presto 14psi out of the hole. Its wicked and works a treat but it just blows my street tyres into the weeds!

Heading to the track next week for some track testing.

[Disturbed1]

i wanted flames oh well guess i might just have to use antilag instead to get off the line...

mine backs ultra stick street tyres leaving on 6 psi (260 hp car)- id hate to imagine what 14 psi does... can u reduce the amount of boost it holds at set rpms???

[oldcorollas]

when it sits on the limites it just bounces off it ever so quietly and shows mega lean mixtures as if its just cutting fuel... would u expect fuel cut to still generate boost in neutral???

if it is cutting sparks there will also be an excess of oxygen, since it is not getting burnt.

put LED's on the injector inputs to ECU and see if they are dropping?

[Disturbed1]

The rpm limiter cuts the fuel out on every second engine cycle e.g. the engine will be
injected with the correct amount of fuel for one cycle and no fuel for the next cycle, in turn
not running the engine lean at any stage.

"

after reading that id deff say its fuel cut


can u see this harming the motor in any way oldcorollas??

[oldcorollas]

after reading that id deff say its fuel cut


can u see this harming the motor in any way oldcorollas??

are you running sequential injection and phased to be in exact timing with the intake event of the valve?

if not, you could do damage then again.... fuel cut is used for rev limiters with not so much damage.. do you want to risk it?
you could just run it like that and see if it blows a piston

(edit: and my point was that both fuel and spark cut will show up as lean on AFR)

[Disturbed1]

point taken

for the very odd occasion that ill be unsing it ill risk it, already tried my 3500 rpm launches and im somewhat impressed


at the drags on super sticky mt and 5000 rpm limiter should be fun - at least i can concentrate on releasing clutch properly then focusing on the revs

[dori dori]

Yes. One of the Haltech guys has it set up on his Evo 9 and he dials up 20psi!!!!! needless to say it is nearly unbeatable off the line.

i wanted flames oh well guess i might just have to use antilag instead to get off the line...

mine backs ultra stick street tyres leaving on 6 psi (260 hp car)- id hate to imagine what 14 psi does... can u reduce the amount of boost it holds at set rpms???

[-==L=a=N=c=E==-]

i have 2 step on the microtech, and have it set to 4000 rpm 4mS more fuel and -20degrees of retard.

I build 7psi with the GT35R.

Launches have never been so fun. And not to mention consistent.

[Mazman]

Yes. One of the Haltech guys has it set up on his Evo 9 and he dials up 20psi!!!!! needless to say it is nearly unbeatable off the line.

the 2 step does shit fuk all on the haltech! i had it and it was just that, a 2 step where you just set your rpm limit and it launches from said limit!

its teh antilag that makes you build boost and retards timing etc etc.

I could never build positive boost on the 2 step, then i enabled teh antilag and now i can build easily 15psi on idle (this is antilag with a two step combined).

When you speak of your haltech guys, who are you speaking of if you dont mind?

[Disturbed1]

fuck.. EMS offer ultra shit instructions with their ecus!!!

does anyone know how to hook up the 2 step function via a switch?? the manual says just connect the digital input (1 of 7 yet dont specify which 1 and ive tried em all) to a switch with closes the circuit to 12 volt power

im stumped cause the only way to activate the 2nd limiter is to click on it on the laptop and the only way to turn it off it to unclick it off the laptop!! kinda useless when u trying to launch at the same time



im also having great trouble getting the wideband o2 sensor to work with the ecu

[DX20VT]

Anti-lag and Launch control are totally different.

Launch control will almost never make boost on the line.

Launch control controls RPM by stoping the combustion by either spark of fuel, and therefore the air in the cylinder does not heat up and expand enough to spin the turbo as the volume of unburnt air is not enough to make boost even at WOT without combustion.

Antilag controls the rpm by retarding the timing, and if set hard enough sometimes to the point that combustion occours in the exhaust manifold rather than in the combustion chamber. As the combustion still occours the air expands enough to make the turbo spin enough to make boost.
The amount of boost depends on Turbo, retard amount, Throttle position i.e.airflow into the engine, and set rpm.

[pornstr20v]

does 2step launch control do anything bad 2 the motor

[LeeRoy]

It is effectively a second rev limiter but with the limit being set in an rpm far from an engines limit. Engine damage is more likely to occur from fairly heavy clutch dumps than it is from the cutting of fuel or ignition.