i have an idea for a home made two step. here it goes. there is throttlebody limiter in the tune for park/neutral and drive. if you took the wires from neutral switch on the trans and wired them threw a switch on the brake pedal. then when you depressed it the computer would think it was in neutral. doing this it would on rev to the set rpm of the park/neutral limit. no i know for daily driving it might not be good for the computer to go into "neutral and drive" all the time. so you could make a bypass switch to bypass the switch on the brake pedal.

so what do ya think would it work??

 

Yep, been there done that, have logs showing around 4 psi in park....
I done ALOT of testing, I never did the wireing needed to make it work. I was going to do what you though of about making the pcm "think" it is park/neutral. I tested it almost everyday, playing with timming as well. Then one day it all changed, the truck ran like crap, and had a knock. I stop "testing" and gave up on the home made two step.

The problem I think I ran into was the fact I was cutting fuel not spark. In my head I though cuting fuel would be better because you wouldn't wash the liners down. But I don't think the pcm can cut the injectors 100%, plus there is still fuel in the intake runner. SO, 2 steps suck if they cut fuel..........

 

well hell i was just gonna use the ETC set it to 3000rpm in park/neutral so that it would be throttle limited to 3000 rpm and leave full spark and full fuel. that way i would have to try and regulate the boost/rpm everytime i got up to the line it would be automatic and pedal be to the floor. of course i would fine tune it at the track for rpm. but you get the idea. chevy is doing it on the cobalt. its throttle limited with the clutch to the floor for launch control and you can shift gears with out lifting the gas pedal.

 

Well that isn't really a 2 step, it wont help build boost, but it would make your launches more consistent.

 

even if you limited to just the point of it pushing threw the brakes?