Bypassing fuel on 2 step

Discussion in 'PSI Superchargers Tech Questions' started by H BROWN, Mar 5, 2009.

  1. H BROWN

    H BROWN blown alky

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    is there a difference on bypassing fuel on the 2 step between a converter car and clutch car? i would think a clutch car on the 2 step at 5000 rpm, the pump would be making x amount of fuel and most car do not use a bypass or lean out, the just let it blow out the zoomies

    but what happens when a converter car 2 steps at 3000 rpm and is tugging on the converter? i would think it would burn more fuel lugging the motor, and the pump speed being down that u would almost want to fatten her up.

    any ideas from converter, blown cars using a 2 step and tranbrake?

    i am confused on what to do with my car, put her on the tranbrake and 2 step at 3000 rpm with butterflys wide open and let the excess fuel go out the pipes, or is she gonna be lean and need to fatten her up, or put a lean out or by pass and lean her out on the 2 step. if I lean her out whats a ballpark jet size on a converter car,same as clutch car?

    using an air throttle is gonna take a lot of mods in my car, so i am trying to find another way.

    thanks for any and all help.
     
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  2. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    throttle control

    I would recommend with the converter to use the air controller to open the blades just a touch more than what you would ever need for launch rpm, then use the two step to limit the rpm, rather than limiting it at WOT. It's just wasted power anyway with the converter and makes it trickier to get off the line. You're probably going to have to pull timing out at the hit as it is, so if you go from making 10 lbs of boost at the hit to 30, you're just making it more tempermental, and may be the difference between having to pull 5 degrees out at the hit and 15.

    BTW, I still think you have too much timing unless you have an extremely low compression ratio.
     
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  3. H BROWN

    H BROWN blown alky

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    hey will,my timing is 36-38, but they are big chamber fuel heads around 11-5 comp. I will be pullin timing this year also just the air throttle deal will be a lot of work to modify to my car, but that may be the ticket.

    u at the adrl, i will be there tomorrow.
     
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  4. td314b

    td314b New Member

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    It can be done.

    H. Brown,

    I have heard for years that you can not launch a converter car off of 2-step with the blades wide open and this is simply not true. We have been doing it for 4 years on our dragster and it is so much easier then the air throttle controls. Granted Will is right that you do have to adjust some things to make sure that you do not go crazy with the power but it is by far the way to go in our opinion.

    I could go on and on about how we do it and all the things you need to consider but it is easier if you just call me if you want to get a 4 year history on this stuff. I can be reached at 800-233-5455

    Troy
     
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  5. Eric David Bru

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  6. Chuxluv

    Chuxluv Member

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    Blower Twostep

    I have been using a two step on my blower truck for years. BBC SSI 32 lbs boost 7al3. Sometimes at 4000/4600.I have used a NOS solenoid to remove fuel when it is decked and on the TB. I found out that when reading the data logger the boost was less when the solenoid was used and boost was more when solenoid was not used.I have noticed by the data that I am only on the two step .7 to .9 tenth of a second.I use this system to affect my light from day and night racing because we race a pro light.Reaction times adverage .009
     
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  7. JRB

    JRB Guest

    You can use a 2 step, no problem. I do it on 3 different motor combination's, and it works great on them all. And as far a bypassing fuel, you can definitely make the car more or less aggressive by allowing more or less fuel to be bypassed. Gimme a shout if you have any questions. Its not rocket science. (916)505-6852.
     
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