Enthalpy

Yup, sounds like you have the boost controller's operation down. The only thing I would reiterate is if you give a huge ramp in lower RPM areas, you might overboost and hit fuel cut as the ambient temperature falls this autumn.

2-step vs. antilag:
2-step is simply implimenting a fuel and/or spark cut at an artificial redline usually activated by a switch wired back to the EMS. You can make this switch the clutch start switch so it only does it when you stage.

The point of this is to provide PERFECTLY CONSISTENT launches with boost. It enables you to nail the perfect launch RPM each and every time. For consistency drag competitions, this is very effective. This isn't usually THAT hard on things, although I wouldn't evoke the system any more than a few seconds every 1/2 minute or so. It will create VERY LOUD BANGS out the exhaust that can sometimes kill cats in short order.

Antilag is where you pull a TON of timing such that the combustion is still happening when the exhaust valve opens!! This dumps a TON of exhaust energy down the manifold to spool the turbo and keep the engine spinning at an optimal RPM. Antilag was originally developed by F1 teams in the 80s to keep their turbos spun up while going around a corner.

Antilag is USUALLY activated using a switch, although some activate it other ways.

WARNING - ANTILAG WILL KILL YOUR ENGINE/TURBO/MANIFOLD QUICKER THAN JUST ABOUT ANYTHING ELSE IF ABUSED!! As you can imagine, burning exhaust valves, warping manifolds and destroying turbo oil seals are closely tied to EGT, which will SKYROCKET while evoking antilag. For this reason, don't evoke antilag any more than a few seconds, waiting at least a minute between.

To keep things a little cooler, you enrich the mixture quite a bit.

You set the alternate 3D fuel and spark maps to keep the engine at the right speed. It can be a bit of a trick, but you detune the motor as it increases above your target RPM, and "retune" the motor in the maps below this point.

So the first step you want to do for setting up either of these features is to figure out your car's optimal launch RPM. Something that lightly chirps the wheels without spinning the tires or bogging the engine.

tdonnell

Cool, thanks for the detailed explanation of the differences and setups.

I don't think I am going to wire up the anti-lag, especially after all those caps you just used warning me not to damage my expensive components. Too risky if you ask me.

But the two step sounds cool, I would like to hook that up ASAP. How do I set that up in the haltech software though? There is no map for it that I can find. If you still have the software it would be awesome if you could help me out here, everything in the manual is very bland. The only possible options I can find are in the input/output section, by using the spare input with AUX RPM limit? Or the Aux IN function? Any help distinguising which one I need to use would be great. Also, can I wire it up to either of the two 3 pin GM connectors? I suppose one is the aux in and one is the spare input??? And are there maps to control the amount of timing the EMS pulls, or do I just set a target RPM?

Sorry for so many novice questions, lol.

And about figuring out the perfect launch RPM; I cant really do that until I start building 15 psi at those rpm points, otherwise where I set it will end up being way to high and blowing the tires up off the line right? As it sits now, about 4500 is just right, but once I have 15 psi, I would think about 3500-4000 tops.

Thanks in advance.

Enthalpy

It's entirely possible to tune antilag if you observe thermal limits.

The E6X is a little lacking in the 2-step area when compared with the E8 and such. I'm doing this from memory, so it might not be perfect. In the E6X, you setup an input to be a rev limiter activation. You go into the main setup and select if you want to cut fuel or spark at the limit. Cutting spark dumps a good combustible air/fuel mix into the turbo that can then combust in the turbo, spiking temps. For this reason, start with fuel and see if you get what you want.

DO NOT do a spark cut if you have a cat! This will kill it quickly.

As for if you can use those specific 3-wire inputs, you probably can, but check the software and see if those inputs are allowed to be a rev limiter. You will probably be given a voltage threashold to use. Set it to 1 volt then wire the switch to short the signal wire to signal ground, which is the black wire in those 3-wire bundles.

You can use a clutch start switch. Some people put a switch on the shifter. You can go hog wild and put a switch on the steering wheel. That might look cool. It's your call!

If you need to go buy a switch, any radio shack setup will work. If you have to wire it to chassis ground, I suppose that's okay, but wiring it back to the sensor ground circuit is preferred. It will be less problematic.

tdonnell

The only way it seems to be able to do it is to set it up under the aux input as an aux rpm limit. Then it lets me set the aux rpm limit I want, but there is no independent adjustment for the aux in rpm limit as far as whether to cut fuel or spark, so I will have to cut fuel like my normal rpm limit right? I don't really hit redline often, could I setup my rpm limit to be spark cut normally? How does the sound differ and will it hurt my engine if every once and a while for 1 second max I hit the spark cut 7500 rpm limit?

Thanks.

Enthalpy

I think the fuel vs. spark is in the main setup where you set how you want redline to be handled to begin with. Once again, I'm operating off memory here since I'm at work.

Hitting the motor's natural redline every now and then won't hurt much. It's when you make a practice of it is when you risk fatigue failure of the rods and such. As for what the EMS does, it shouldn't hurt much at all if you are cutting fuel. Cutting just spark can KILL the cat quickly, and there can be interactions with the turbo as combustion will sometimes happen in there. It won't instantly kill the turbo, but you want to manage its temps so you don't kill the turbo's turbine oil seal.

tdonnell

So as long as I don't hit redline too often I should be fine cutting spark for it?

I am saying in the main setup is where you set the aux rpm limit that is activated by a switch I assume.

99mini

my SDS standalone (http://www.sdsefi.com) includes the option to cut the fuel at whatever rpm you want, eg at redline. but one of the tuner shops told me this design (cutting fuel as a rev limiter) can result in the engine running lean/grenading.

so my computer fuel cut is set at 7500 rpm, and the tachometer shift light is set at 7000 rpm, and i shift as soon as the light flashes. hopefully i never experience the consequences of a fuel cut at 7500 rpm.

Enthalpy

I'm not familiar with SDS systems, but it is fundamentally stupid to think you are going to grenade an engine if you COMPLETELY cut fuel from one cycle to the next. How am I going to detonate if I have NO GAS with which to detonate?

Either the shop's tuner isn't thinking of this, or something is getting lost in the translation.

An example of loss of translation might be if you try to "trick" a fake fuel cut using the base fuel map. The EMS will interpolate between a cell that has a valid fuel value and another cell that has a zero in it. So in THIS case, yes, it's possible to go lean depending on the spacing of the cells.

However, that would be a VERY hacked-together way of implimenting a fuel cut.

I can guarantee the E6X's 2-step does NOT do this hack method. The E6X will COMPLETELY cut the fuel between cycles on a given cylinder so you either have CORRECT fuel, or NO FUEL. There's no worry with the E6X.

tdonnell

Yeah, you would be more likley to detonate and grenade (lol, love that term) an engine if you were to cut spark and the combustion chamber hot spots were at a high enough temp to ignite the fuel mixture after the spark cut. I think that would even be a rare circumstance though.

As for the two step, any new info once referencing the haltech software Damon?

Thanks bro.

Enthalpy

That's preignition, which is EVIL. You shouldn't EVER have that condition!

Under main setup, select RPM limit type, select fuel or ignition.