I've been trying to read up on this subject but I'm getting sort of confused and there really isn't much information out there about it.

What is the difference between anti-lag and a two-step? What are the pros and cons to each? Anything rotary specific that is prevalent ?

I am currently running a haltech E6k and stock ignition with an HKS Twin Power. What would be the best solution for me to build boost at the line?

Thanks in advance.

 

Anti lag retards the timing and adds extra fuel. The plugs are fired later (retarded timing) and that causes the mixture to still be burning when the exhaust port opens. The burning fuel in the exhaust drives the turbo instead of providing power for the engine. As soon as the clutch is released the timing and mixture go back to normal.

A two step is basically two separate rev limiters. The second limit is the one that keeps your engine from overreving (redline) the first one is set at a lover RPM and is designed to generate boost. It works in two separate ways. First as the engine has to rapidly accelerate and decelerate when it hits the limiter putting an artificial load on the engine and causes the turbo to spool, second the unburned fuel from the ignition being cut will burn inside the header and help spool the turbo.

They both have their setbacks though. The anti lag generates very high EGTs and is hard on the turbo and header. The rapid oscillation of the two step puts added stress on the internals of the engine (especially corner seals).

Allen

 

Damn, I thought they were the same thing! If I launch my car off the rev limiter, would this be the same thing as a two step?

 

Nope, I think I've told you that before.

I used a MSD Two Step Box. I hooked up two relays to shut off my trailing coils while the two step is engaged. I was able to boost about 18 psi off the line. I tried launching with it a few times but it was too cold outside and it would just blow the tires away.

 

FYI: I was able to cut a 1.43 off just holding the RPM'S at 6500 and dropping the clutch.

 

It depends on whether you limiter cuts fuel or spark. If it cuts spark you would get the same result as a two step (more or less).

Allen

 

i've been debating getting a two step system for a while my buddy has it in his sti. he let me drive it and i love the thing! though i just dont really know how it acts out on the rotary engine (hearing that you can hook it up differnent ways). can i hear some more information please?