new way to stage

Discussion in 'PSI Superchargers Tech Questions' started by NITROBANDIT1, Nov 6, 2009.

  1. NITROBANDIT1

    NITROBANDIT1 LOST IN SPACE

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    looking for some sound advise on staging a fc. we have a alchohol funny car with a automatic trans. msd 44, kb,etc. currently we have done well, but are looking for a way to better the reaction times, and make them more consistent. car runs in the high 6 second range around 200, right now we are using the gas pedal directly connected to the butterflies. we cannot use a digital retards in the ignition per rules. some in our class use a air cylinder to control blade release speed on green, some argue this is illegal, some dont. right now we just use the 2 step and manage throttle opening. the car was built with 1 inch stagger in the front end, we will be relocating the other side to match 125 inch wheelbase side to side, and changing tire sizes also. is there any way( i dont mean a traction control chip hidden under the seat) or anything that is a known legal way to do this a little better. we have the trans brake switch on shifter and is adjustable and high quality.it is index fast bracket racing, so consistensy is important. anything the pro mods use that we could? im not a widget person, so am not schooled in this stuff very well.i can read between the lines on some rulebooks, but it has to be cut and dried legal to use. thanks
     
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  2. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    skinning the cat

    If digital mag retard is illegal, you could get an air operated mag retard like the fuel cars used to run. This would actually retard the mag on the drive by air.

    I've heard of people doing the same with crank triggers, too.

    If fuel management is allowed you can run the fuel system real rich with a normally closed leanout to open at a predetermined point to bring the fuel system back to the correct a/f ratio.

    I don't know why they are afraid of timing management.

    In setting your air controller, set the opening slightly above what your target rpm range will be, then adjust the rpm with your two step chip.

    Monitor head temp and trans temp since you are dial/index racing. You want your head temp the same just as you would your water temp in a bracket car. As you make more runs and the motor gets a heat soak, you will have to richen the barrel valve to maintain the same head temp. If you are not using synthetic trans fluid, typically you will go slower as the fluid gets warmer. I don't know how much this affects a blown motor, but it was critical to monitor in my sc dragster. Also if you don't get the fluid up to normal temp before the first run, usually the first run is a bit slower. Since you probably don't drive this car around the pits, this can only be accomplished through stalling the transbrake a couple of times.
     
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  3. Bob Meyer

    Bob Meyer Comp Eliminator

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    Win by 2"

    Dan; you better call me. The last thing on earth you want to do is fool with the stagger. I also think your car has 2" as it should. You are not S/C racing using delay boxes and looking for whatever they call "the package".
    If your car has no stagger, his does, you both have perfect lights of .000, both run 5.8000, you will lose by 2" everytime!!!
    Why ??, because his back wheel was holding the beam open while the car is now 1-15/16" out on the track!
     
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  4. Woodchip

    Woodchip Top Alcohol Dragster

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    Bob, if his back wheel holds the beam open and he runs he same et . his car would have to physically run slower by that two inches for the ET to be the same. Otherwise he would break out. And it wouldn't be two inches at the finish line. It would be the time interval of those two inches at the starting line translated to the same time interval at speed as you cross the finish line. which could be several feet.
     
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    Last edited: Nov 6, 2009
  5. Outlaw68

    Outlaw68 Member

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    removing the stagger "WILL NOT" make you lose a race if both cars leave the same and both run the same. Stagger was made to increase roll out for a better rolling start, this by nature will SLOW reaction times down.
    However, you should be able to go RED on a .4 protree with that car, even with the stagger and it would be the last thing I would change.

    A couple of things you can do. Smaller front tire?, TUBES in the rear stiffen that rear tire sidewall up will make the car react faster. Tightening the convertor up will as well..

    If you dont have a HIPSTER valve body, I WOULD GET ONE!

    I am racing this weekend, but when I get back home and have a chance to post more I will. One thing for sure is, I would move the button from the shifter to the steering wheel, you will be quicker if the button is in front of you, as it takes less muscle movement to react there. I have 20 yrs plus of experience in this dept.
    When you say you do pretty good, explain? Give me the RT from your last 5 passes.
     
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  6. Outlaw68

    Outlaw68 Member

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    And btw.. If your back wheel is holding the beam open, you staged with the wrong end of the car.. The FRONT tire breaks the beam. :)
     
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  7. Bob Meyer

    Bob Meyer Comp Eliminator

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    Well, i wish I could type faster..........
    If you have stagger, you have one side forward and the other is BACK.
    There is only one beam in the system that is held open.
    When that beam closes, a clock starts when the green comes on. It stops with a count when the beam is no longer held open by the backside of the further back FRONT wheel. It's called a reaction time!
    In the case I mentioned, both having .000 R.T.'s...........
    follow this closely now..........
    The guy with the stagger is already out on the track by 2 ", meaning his lane will be 1319'10".
    The backside of the further back tire has kept him from redlighting because the beam couldn't reconnect.

    Remember those stupid little dragster wheels? It made some "stars" out of old guys, as far as reaction times, but the fact was that the guys with the big wheels were leaving on them because the bigger wheel takes more time holding that beam open. Most of the lookie loos finally figured it out and the fad was over. Ever see a S/S car with little tires?
    Think about it completely, or better still, get your hands on a track timing system set up guide (as I have) to help understand how it really works. Then apply what you've learned to how you stage your car.

    I had the pure pleasure of working with one of the best there ever was at staging a car consistantly, D.R.(RIP)

    Also, because this is what I thought to be a board concerning ALCOHOL cars, it just dawned on me that some are thinking bracket racing with breakouts, which is not something that concerns me, and I don't wish to learn.
     
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    Last edited: Nov 7, 2009
  8. Woodchip

    Woodchip Top Alcohol Dragster

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    Bob, as far as cars who compete without breakout, yes, Roll-out is an advantage. But in brackets with both cars running identical ET's The car that runs 1319'10" MUST run slower to get the same ET.
     
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  9. Woodchip

    Woodchip Top Alcohol Dragster

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    Which was the original posters point, fast bracket racing. In the eighties I volunteered to help build a super comp dragster. We hemmed and hawed about the benefits of stagger and no stagger. After hashing it out we built it with no stagger at all. The guy won the division one super comp championship with that car with a small-block that was so underpowered it barely would run the number. To my knowledge all super comp cars out of that chassis shop since had no stagger.
     
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  10. kosky racing

    kosky racing Comp Eliminator

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    Stagger

    Don't believe stagger matters you still stage with the edge that gets there first. ????? Mike
     
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  11. Bob Meyer

    Bob Meyer Comp Eliminator

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    W.Chip; duh..... too old to read full sentences, missed that.
    So, I burned up my finger for nutin.:eek:
     
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  12. Woodchip

    Woodchip Top Alcohol Dragster

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    With no stagger your et will suffer, With stagger you get an additional two inches of roll out before the et clock starts. During rounds a few (McPhillps) use this two inch of stagger to go deep and put their car closer to the finish line.
     
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  13. Bob Meyer

    Bob Meyer Comp Eliminator

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    Mikey; don't forget the finishline beams are 6-7" off the ground and if you do it right, the nose/tip plates trip the beam, not the front tire.
     
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  14. Woodchip

    Woodchip Top Alcohol Dragster

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    drag race to 1317 feet 4 inches

    yes so its actually a quarter mile less the roll out including the two inches less the allowable 30 inch overhang.
     
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  15. NITROBANDIT1

    NITROBANDIT1 LOST IN SPACE

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    better rts

    yes, i could mention the car does has slightly oversize tires on the front, a real fc tire is about 11/2 inches smaller in height compared to whats on it, and the rear tires have safety liners also. like the original post said, this is only about getting better rts for now, the average is about .60 to .100 and the driver is consistant and a veteran of the drag wars. heres the problem, most of the races that were lost were by very small margins. .006-.009. most wins were easily decided. the theory is to pick up the rts and make them better, increasing the percentage of wins that were usually lost my small margins. we are building a 80 inch overhang piece of pipe to hit the high side beams right now out of an old flagpole! that will guarantee getting the stripe every time i hope!:eek:
     
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  16. Rockin' Robin WKR

    Rockin' Robin WKR New Member

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    The way I see it, to quicken the reaction time you could roll in deeper, put on smaller tires, run more air pressure (raises wheel), remove the stagger, and/or any combination of the above.

    After that it is probably in the converter and how you launch with the two-step.
     
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    Last edited: Nov 8, 2009
  17. kosky racing

    kosky racing Comp Eliminator

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    Stagger

    The starting line does not know stagger. The finish line only knows what gets there first. Front leading edge of the wing or the tire? ------mIKE
     
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  18. Bottlefed

    Bottlefed New to Blowers

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    Rollout, taken from NHRA's website

    Racing Technology
    Rollout and reaction time —
    more important than you might think

    by Wayne Scraba


    Rollout is a familiar word in drag racing. Even if you only occasionally race your car in brackets, it's a term that could save you countless red-lights. It also can improve the vehicle's elapsed time and help if you're late. Sound interesting? It is. Best of all, most rollout improvements are free of charge — or at least cheap.

    How the system works
    Virtually all contemporary dragstrips feature a pre-stage and a stage beam (many also have what is called a "guard beam" that starts the e.t. clock if the stage beam does not). The pre-stage beam is approximately 12 inches ahead of the stage beam; however, this distance can change from track to track or, in rare cases, may change during the course of an event.

    To chart your progress as you stage your car, corresponding lights are affixed to the Christmas Tree. The pre-stage bulb tells the driver that his or her car is about to enter the stage beam — which, in essence, is the dragstrip starting line. When the front tires of the car pass completely through the stage beam, the timers begin. If you start too soon, the evil red-light comes on and you go home early.

    According to Jerry Bickel, "Increasing the rollout distance of a car gives the racer advantages that can make the difference between winning and losing. The added distance means that a little more time will elapse before the light beam reconnects. This makes it less likely that the driver will red-light, and the car gets a running start to cover the quarter-mile. The length of the track is also shortened slightly by the increased rollout distance.

    "On the downside, increasing the rollout distance of a car will also increase your recorded reaction times. If your reaction times are good, you should increase the rollout distance as much as the rules allow." More on this topic later.

    The connection
    The folks at Port-A-Tree have done a considerable amount of research into rollout. I highly recommend the company's comprehensive video on the subject. According to Port-A-Tree, "Rollout is the ability of the car and the driver to react to the Christmas Tree lights and to leave the starting line at a precise time.

    "No matter what class, the driver with a better reaction time has a better chance of winning the race. Reaction time, as a number on the e.t. slip, measures the driver and the vehicle performance at the starting line. The driver reacts first, with a foot off the clutch, a finger off the transbrake button, or a foot off the brake pedal. The response to this action is the vehicle reaction time, or rollout. Variables that influence reaction time include engine rpm, clutch or converter slippage, tire spin, engine performance, front tire diameter, suspension setup, staging technique, and any combination of the preceding.

    "The movement of the tire out of the stage beam is what stops the reaction-time clock and starts the e.t. clock. The stage beam must be blocked by the vehicle tire at the beginning of the Tree sequence, and the beam must be unblocked the instant the green light comes on."

    Time constraints
    According to the folks at Port-A-Tree, a specific amount of time is required for the Christmas Tree bulbs to work. This is called trigger time, which equates to 0.040-second. Port-A-Tree has also determined that the average driver reaction time is 0.140-second, plus or minus 0.020-second. This means that, all told, a driver requires 0.180-second, plus or minus 0.020-second, to react to a given bulb on the Tree. When this is taken into account, the driver reaction time can, in fact, be taken out of the equation, leaving just the race car, the burnout process, and a few other items to influence overall reaction time.

    What parts of the vehicle can you change to influence reaction time? As mentioned by those at Port-A-Tree, engine rpm, clutch or converter slippage, tire spin, engine performance, front tire diameter, suspension setup, and staging techniques affect overall reaction time. One of the easiest mechanical things to change is the front tire diameter.

    According to Jerry Bickel, tire rollout is critical. "There are only two ways to legally increase the rollout distance: Use larger diameter tires or stagger the front wheels," he said. "Race sanctioning organization rule books [NHRA's included] allow a certain amount of wheelbase stagger. This means that one tire (usually the right front) is positioned slightly behind the other. Because the light beam is broken by the front wheels at the starting line, wheelbase stagger increases the rollout distance by the same amount."

    Unless the car in question is a purpose-built drag machine (dragster, altered, Funny Car, Pro Stocker, and the like), it's extremely difficult (if not impossible) to change the front tire stagger. In cases such as this, the best bet is to physically change the overall diameter of the front tires. As you can imagine, the front tire diameter and, to a certain degree, tire pressure play a serious role in determining rollout.

    By increasing the size (diameter) of the front tire, rollout is increased. For example, most of today's street cars are fitted with low-profile tires on all four corners, and these tires are substantially shorter than an old-fashioned 78-aspect ratio tire. By adding a tall tire, such as a 78-series or a dedicated drag race front tire, rollout is increased.

    How much can rollout change? Take a look at the chart below from Goodyear. For the sake of comparison, only non-dragster tires are listed.

    Size Diameter Overall Rollout Overall
    23.0x5.0-15 23.0 inches 72.2 inches
    24.0x5.0-15 24.0 inches 75.4 inches
    25.0x4.5-15 25.0 inches 78.5 inches
    26.0x4.5-15 26.0 inches 81.7 inches
    27.0x4.5-15 27.0 inches 84.8 inches
    28.0x4.5-15 28.0 inches 88.3 inches


    Note that the rollout measured above is the total rollout of the tire. In essence, that measurement is how far the tire moves in one complete revolution. The chart does, however, show just how much rollout difference there is between various sizes of tires.

    Running starts and red-lights
    The bottom line is that an increase in the front tire diameter provides the racer with greater insurance against viewing the red eye on the Christmas Tree. In simple terms, the tall front tire will roll further without unblocking the stage beam, effectively fooling the starting system. In addition, increased rollout allows the car to literally take a running start (albeit a short running start measured in inches) when the Tree comes down.

    If front tire pressure is increased, the overall diameter of the tire is increased, which in turn increases rollout (at least in theory). Conversely, if the front tire pressure is reduced, the rollout decreases. I should point out, however that a number of racers have tested this theory, and when kept within safe levels, it's often difficult to see much change by raising or lowering tire pressure. You'll also find that excessively lowering the front tire pressure can have an adverse effect on handling, especially at the big end of the dragstrip. Practically speaking, you're probably better off playing with front tires of a different diameter.

    When using a tire diameter advantage on the starting line, be absolutely positive that you bump your car slowly into the pre-stage and stage beams. This is called shallow staging — a process that works well with street-strip vehicles (or footbrake cars) that do not have outstanding vehicle reaction times. If you drive right through the beams, the advantages of more rollout are tossed out the window.

    In the end, you may find that by "adjusting" the rollout, you will be capable of cutting better lights (i.e., reaction times decrease) while at the same time lowering the elapsed times (i.e., the car now has a running start).

    The price? In the big picture, next to nothing. Down the road, we'll take a close look at varied (and precise) starting line rpm, "adjustable" travel transmission brake switches, and other reaction-time factors. In the meantime, think long and hard about rollout. A simple front tire swap can often spell the difference between going home early and enjoying the spoils of competition.
     
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  19. tafc155

    tafc155 Member

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    Al,
    If I remember right, Celko wanted to put stagger in and I wouldn't let him.
    Duane
     
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  20. Woodchip

    Woodchip Top Alcohol Dragster

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    The results are.... Staggering

    Me and him talked about it for quite awhile. Probably after you told him no stagger. I suggested no stagger. Did Donny's car have stagger? I don't remember.

    Al Smith
     
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