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E=Mc2

Discussion in 'Ask The Pros' started by ratrodsrule1, May 23, 2020.

  1. ratrodsrule1

    ratrodsrule1 League Racer

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    No turbo, no nitrous, no twin screw, no motor. No nuttin y’all. Gravity,friction reduction, weight placement, proper drill/alignment, some aero, inertia, The Cycloid of Constant Time and 42’ is all we got.

    So with 42' to work with why is the standard steer targeted @ 4’ ? Is there a reason why a longer steer target isn’t a better choice to keep the Front D off the rail a tad longer and not scrubbing off speed. Surely with the knowledge on this forum someone can splain it to me as I am learning the way of league racing and open to wise counsel.

    Thanks.......RRR
     
  2. Jimmy & his 2 Kids

    Jimmy & his 2 Kids National Contender

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    I’ll take a stab at this. 2 points you mention or ask about in this question...
    longer steer... assuming asking why not more than 4” based on your wording?
    Keeping DFW off of the rail... meaning keeping the wheel from contacting the rail as much so as to not scrub speed based on your wording?

    These 2 contradict each other. More steer makes the cars steer harder into the rail. The only way to have DFW not connect the rail as hard or as much is less steer.

    Point of steer... keep car from bouncing/wiggling back and forth which scrubs a ton of speed. Each subsequent pull away then back to impact rail is a speed killer.

    What we are doing with these little beasties is trying to do controlled chaos. Making a fast moving car at this small size down such a long (in relation) track it is physically impossible to make a car go STRAIGHT. Just can’t be done. That’s why we use the rail. It’s a necessary evil. Better to ride smoothly on that rail than bounce and wiggle all over the place.

    The amount of steer creates the amount of force your car’s tendency to drift to one side is creating up against that rail. Not enough steer and the cars tendency to get all squiggly will overcome the DFW’s steer. This results in the dreaded wiggle. The cars wiggle will make it drive away from the rail. You know what happens next including loosing the race.

    Too much steer and the car will be rock steady with no wiggles but it will have more force than is needed to hold the car steady. This then slows the car down as the DFW is forcing the car harder than is needed into that rail. Now you have your brake affect after the transition.

    Main goal... find that sweet spot between too much force holding car too tight to the rail, and not enough force allowing the cars inherent tendency to wiggle off of it.

    It does seem after a lot of folks before us have gone through a ton of trial and error that a typical car on an average track does well enough at about 4” of steer.

    This is a safe starting point and what a lot of guys who do not have a track to tune on will go with. This is also why “easy steer” drill jigs like Micro’s 5 bushing clear jig have that 5th built in steer bushing set to give a car 4” over 4’ of travel. Quite a nice tool for typical Scout/Awana level racing.

    Now you can then of course dig deeper as you get better, do more classes and race on different tracks AND have a test track to tune on. There are a lot of variables which at the league level (.0001 make or break level) that can cause a car to do better at a different steer amount but it is really best not to cross that bridge until you get there.

    Case in point.... some fat wheel classes guys who really know what they are doing actually go less, even as little as 2” or less steer. Then the mini class... those little freak shows need more than 10”!!!
    Again... best advice on that, don’t cross that bridge until you get there. Me, I don’t even want to go near that bridge right now. lol

    Hope that jibber jabber helped some and was what you were asking and didn’t add confusion.

    Race day is here!!! Time to see whatcha got!!!
     
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  3. ratrodsrule1

    ratrodsrule1 League Racer

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    Mr. Jimmy could you go into more detail ? LOL LOl....good job of splaining it !! I keep forgetting this isn't a new sport/hobby/addiction and everything under the sun has been experimented or considered. But I always try to think outside the box. Edison din't fail he just found a thousand different ways not to build a light bulb.

    I was hoping a correctly weight biased and aligned car would stay straight enough without wiggle to go beyond the 4' mark BEFORE making rail contact thus scrubbing off less speed. But I'm in total agreement with you in regard to the relative scale of these little units where even the earths 23 degree angle rotation on its axis may come into play LOL. Dang these little things are touchy and don't have a very sunny disposition when messed with .
     
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  4. Jimmy & his 2 Kids

    Jimmy & his 2 Kids National Contender

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    Keep in mind... rail width on a Best Track is 1 5/8". Width of car block is 1 3/4". You basically have a tad over 1/8" total room both sides together depending on your wheel gaps. Chances are your car is hitting the rail way before the first 4'. Spending energy on trying to affect and lengthen the time it takes a car to actually come in contact with the rail... with all due respect... you can let that one go brother. But that's just based on my not-so experienced thinking though. Just my humble opinion.
     
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  5. ratrodsrule1

    ratrodsrule1 League Racer

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    I respect your opinion but slightly disagree but that's how friends behave. I never mention names but a good Forum friend Pro has run a sub 3 with a non steer car. So it can be done but I can't imagine the depths of preps it took to do that. So extending the contact point of a steer car beyond the 4' mark should be possible.
     
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  6. Jimmy & his 2 Kids

    Jimmy & his 2 Kids National Contender

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    Possible? Sure. A worthy endeavor? That’s where I’m not sold. But I’m certainly curious to see what you come up with.
    We are having our first non-family gathering tonight. Our governor just opened up gatherings up to 10. Though the stay at home gig has been extended thru mid June.
    But as we are gathering I’ll be trying to dodge all the questions of why I keep staring at my phone as I watch tonight’s race to see how your cars do!
     
  7. B_Regal Racing

    B_Regal Racing PWD Royalty Pro Racer

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    That was a great description of steer, wiggles, and friction - maybe the best one I've ever read.
     
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  8. Roadrunner

    Roadrunner Pinewood Ninja

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    +1. Thanks Jimmy
     
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  9. Jimmy & his 2 Kids

    Jimmy & his 2 Kids National Contender

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    Whoa... B_Regal, that means a lot to me coming from an accomplished pro. I wasn't 100% certain I had it all correct or said that right. But that is how I've taken to understand it. Thanks for the vote of confidence man. I really do appreciate that.
     
  10. B_Regal Racing

    B_Regal Racing PWD Royalty Pro Racer

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    Hahahahaaahahaaa.... Pro? Not me. I have not raced in over a year, but I am planning on it. In the interim, I get to mooch some excitement from another racer that lives near me.
     

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