Your experience foot brake vs. 2 step regarding ET

[Rusty Davenport]

Maybe someone will see this and reply but has anyone experimented with low rpm 2 step ......will the motor respond ok on the 2 step at 2000 ????

[Rsmith38]

Don't know about 2000 but my R/SA Jeep 4.0 leaves fine at 2550 - down from 3000 because the brakes won't keep it from pushing thru the lights!
4.0 is FI so can't say about a carb reacting.

[Rusty Davenport]

I'm finding out little by little with experimentation, and it gets back a little to what some of you hinted around to, the quadrajet does not like "rich" fuel mixture when leaving on the mat with the 2 step activated by the brake. It will sit on the starting line and hold the RPMS but when you let go the "rich" will usually make it leave terribly, even though it will run great with the same carb setup when running with the footbrake only.
MAKING THE 2 STEP WORK WITH THE QJET IS A CHALLENGE in order to get it to perform at its best especially on a stocker that doesn't have a transbrake and has to leave at much lower RPMS......by what I am seeing testing the 2 step requires leaner setup to run at least reasonably well.
Does anyone else have similar findings ????

[Danny Ashley]

Plug the accelerator well tubes

[Rusty Davenport]

Originally Posted by Danny Ashley

Plug the accelerator well tubes

Hey Danny sounds like what I've been looking for......but please don't leave us hanging.....can you go into a little depth on the "accelerator well tubes" PLEASE SIR or anyone else who has done this.....THANK YOU

[Rusty Davenport]

Originally Posted by Rusty Davenport

Hey Danny sounds like what I've been looking for......but please don't leave us hanging.....can you go into a little depth on the "accelerator well tubes" PLEASE SIR or anyone else who has done this.....THANK YOU

Is that the same as "SECONDAY ACCELERATOR WELL TUBES"

[Danny Ashley]

The accelerator well tubes are the outer 1/8 inch diameter brass tubes in the air horn. They need to be plugged or removed for 2-stepping. However it isn't necessary, but will help the rich condition the moment the 2-step is de-activated. I have had racers with O2 sensors tell me their A/F would go as rich as 10.5 the moment the trans brake was released. I was told my someone a lot smarter than me that while on the 2-step puddling occurs in the intake because of the cylinders being canceled and the moment the button is released the excess fuel enters the cylinders causing the over-rich condition. My preferred method was to tap the tubes for a 3-48 stainless steel set screw. This allowed the racer to go back to foot-braking simply by taking off the airhorn and removing the set screws. You can just pull them out and if you decide to install them just flip them around for a press fit as they are swedged from the initial installation. They should be staked in regardless as they have been known to fall out even from the factory. Hope this helps.

Originally Posted by Rusty Davenport

Maybe someone will see this and reply but has anyone experimented with low rpm 2 step ......will the motor respond ok on the 2 step at 2000 ????

I used to leave at 2200 with my 455 Lemans. I did what Danny said. blocked off the accelerator tubes and it left great. Always to the floor.

[mat H/SA]

Originally Posted by Todd Hoven

I used to leave at 2200 with my 455 Lemans. I did what Danny said. blocked off the accelerator tubes and it left great. Always to the floor.

with the 2 step??

Originally Posted by mat H/SA

with the 2 step??

yes, the only way I could hit the tree in that car