Cammed 2-step = dangerous?

[metrogdor22]

Originally Posted by pyroguy

This may be an ignorant question, but what is a 2 step?

To add on to what SynergyGreenSS said, a 2-step rev limiter gives you a second rev limit below your redline. It does this by cutting spark. A side effect is unburnt air/fuel mixture entering your exhaust and igniting from the heat, giving you loud pops and commonly flames. It'll blow your cats right out, so most people don't run a 2-step with cats.

The benefit for N/A cars is that it holds your RPM at whatever limit you set for consistent launches. If your car likes to be launched at 3500 RPM exactly, a 2-step will take care of that so you are focusing on the lights and not your tach. If you have a turbo, it does the same plus spools the turbo. But it's also a great way to melt the hot side of your $4500 Garrett.

There are a few ways of implementing it, but us LS guys get it easy. MSD and Lingenfelter make a plug-n-play module that just plugs into your coils. Set the RPM, wire the activation wire to whatever you want (typically a clutch or brake switch with an inline arming toggle), and you're good to go. You can also do it with a tune to customize activation for things like AFR, gear, spray, whatever.

[metrogdor22]

Originally Posted by SynergyGreenSS

I’m no professional, but shouldn’t dumping fuel into the cylinders without igniting it have something of a cooling effect? Or am I way off?

It probably does to an extent, but it's a concern because unburnt fuel will wash oil off of cylinder walls. I don't think it's that much of a concern if you're not bouncing off your 2-step for 10 minutes. But like you said, I'm no professional either.

[Russell James]

Using an aftermarket 2 step... yeah you don't want to sit there for minutes hammering everything to death with all those misfires. A couple seconds tops. If you ridiculously over did it, I'd bet the first thing to go would be the balancer up front slipping.

Which is the beauty of the factory two step (launch mode)- smoother, no misfires hammering the bejesus out of your balancer. Most people don't even know there is a factory two step. And it does it smoothly, just holds the RPM steady while your foot is matted. If in Comp mode.

[mmaattppllaayy]

Originally Posted by Russell James

Using an aftermarket 2 step... yeah you don't want to sit there for minutes hammering everything to death with all those misfires. A couple seconds tops. If you ridiculously over did it, I'd bet the first thing to go would be the balancer up front slipping.

Which is the beauty of the factory two step (launch mode)- smoother, no misfires hammering the bejesus out of your balancer. Most people don't even know there is a factory two step. And it does it smoothly, just holds the RPM steady while your foot is matted. If in Comp mode.

Factory launch control is not a 2step. It is a throttle blade regulated rev limiter. It isn’t much good for building boost quickly. Also isn’t as safe as an actual 2 step because fuel is sometimes removed to maintain that rpm.

[Badbubba]

I've read that the manual cars get alot of wheel hop and axles breaking while using the factory launch control. I got hop wheel hop using launch control. Launch control is used in competitive mode, which limits the amount of wheel spin. By varying ignition timimg, throttle position and or brakes.

[christianchevell]

Metro you should be talking to a experienced shop and let them answer your questions, of course there are problems with ingesting Nitrous into your engine, not all cams, pistons, rings etc made equal or best for various stages varied nitrous kits can be installed for.

Timing , LSA, duration and overlap all matter to some degree and having the engine tuned for the correct AFR matters a lot avoiding ever going lean matter big time...IMO and good plugs and maintenance etc all matter as using a power adder presses a engine to more. Many have on here over time done a 200 or more common 150/100 shot or less on the stock engine with great success but also with problems you may be able to read up on in the threads in the FI section. SO the cam you get matters, I know TSP, cam motion, tick, jannetty, livernois , lingenfelter, etc etc make as many make a more nitrous friendly cam or basically cams that can handle a simpler low spray system...... Good Luck.

And BTW a upgrade of the trailing arms and toes with good poly bushings is good to avoid wheel hop and many do not use the factory launch as its meant for stock engine and at 4000 rpm, a good launch is more when built in the 3500 area IMO; and sticky tires and wheel hop do make a stock axle stress to possibly break when the car is built. Where you have your Nitrous window and engagement RPM set matters and custom tuning matters and even where you have the nitrous switch located can matter, many even like to alter shift knobs to accept the switch.. a lot too just a "simple" install if you want to do it correctly and be safe, but yes long term use...not so good for unforged pistons /normal rings like stock hypereutectic. And yes everything costs money$$$$ And the more shock you put to everything the more $$$ to be durable and longevity wise.

[metrogdor22]

Originally Posted by christianchevell

Metro you should be talking to a experienced shop and let them answer your questions, of course there are problems with ingesting Nitrous into your engine, not all cams, pistons, rings etc made equal or best for various stages varied nitrous kits can be installed for.

Timing , LSA, duration and overlap all matter to some degree and having the engine tuned for the correct AFR matters a lot avoiding ever going lean matter big time...IMO and good plugs and maintenance etc all matter as using a power adder presses a engine to more. Many have on here over time done a 200 or more common 150/100 shot or less on the stock engine with great success but also with problems you may be able to read up on in the threads in the FI section. SO the cam you get matters, I know TSP, cam motion, tick, jannetty, livernois , lingenfelter, etc etc make as many make a more nitrous friendly cam or basically cams that can handle a simpler low spray system...... Good Luck.

And BTW a upgrade of the trailing arms and toes with good poly bushings is good to avoid wheel hop and many do not use the factory launch as its meant for stock engine and at 4000 rpm, a good launch is more when built in the 3500 area IMO; and sticky tires and wheel hop do make a stock axle stress to possibly break when the car is built. Where you have your Nitrous window and engagement RPM set matters and custom tuning matters and even where you have the nitrous switch located can matter, many even like to alter shift knobs to accept the switch.. a lot too just a "simple" install if you want to do it correctly and be safe, but yes long term use...not so good for unforged pistons /normal rings like stock hypereutectic. And yes everything costs money$$$$ And the more shock you put to everything the more $$$ to be durable and longevity wise.

Thank you for the advice, but I think I'll stay away from nitrous for a while.