Author Topic: Need a base point for set up on a 1/4 mile dirt track Please help  (Read 16300 times)

Gimpster

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Re: Need a base point for set up on a 1/4 mile dirt track Please help
« Reply #15 on: July 19, 2013, 03:22:12 pm »
 ( chuckles at the air pressures ). Honestly, my thought was "Who the 'ell would base set-up a chassis with something posted from the internet back in 2007 ?"... looks more like a set-up that melted on the asphalt back in around 2001. Nix, nada, null. So basically, if you throw that base set-up into the chassis,you will be in for a 12 year learning curve through the school of hard knocks (no offence Dennis) by time you figure it all out. Better off starting off with wut DJ threw out there as a base line. LMAO at the 1 pound of air, Steve. Thanks for the visual. Wrinkle walls coming off the corner like a top fuelie smoking away from the tree. Might I suggest tubes in the AR tires at that low of poundage ? BTW if your local tire store doesn't have 13 inch tubes, install 14 inch tubes.

~G~


Offline justfreaky

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Re: Need a base point for set up on a 1/4 mile dirt track Please help
« Reply #16 on: July 19, 2013, 07:27:08 pm »
Question asked for a base set up. If he doesn't have current set up numbers, I would rather give him something I know worked and let him adjust from there.
There are lots of variables to any set up. What works for me may not work for you. We might race different tracks (paved, dirt, road course). We get a lot of new members that either have no racing experience, or no experience with these types of cars. Tire pressures are a fine tuning adjustment. If the spring rates and weight percentages are all screwed up, it doesn't help what-so-ever.

Steve
Better to be hated for who you are, Than to be loved for who you are not.


Gimpster

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Re: Need a base point for set up on a 1/4 mile dirt track Please help
« Reply #17 on: July 19, 2013, 09:36:55 pm »
Not being grouchy in reply, but I disagree with the 'only fine tuning' comment with tire pressures.  Set a Legends Car on the scales with 20 pounds of air in all the tires. Let 10 pounds out of the rears only and watch the numbers change. Same amounts as a spring change would yield or adjusting air presuures enough to change the rake of a chassis. Another view is that by letting air out if the tires, you change the compression or rebound effect on that corner of the car as would a shock valving change. The biggest thing to overcome on these cars is their design, which is that have a built in push. The recommended 2007 set-up for dirt still has a push. Want a base set-up for a starting point ? Install 200 pound springs all around, lay the caster back on both sides about 3 or 4 degrees, 4 degrees of camber leaned in at the top of the front tire on the right side and 2 degrees leaned out on the left side (for oval racing). Toe the front wheels out about 1/8".  Square the rear end, set your ride heights the same all the way around. Go out and run some laps and kind of easy, not pushing it hard, then go out for a few more laps and run it as hard as you can. See which driving style that you prefer and make adjustments to the chassis from there. Biggest problem with trying to suggest a base set-up for someone that you never met is that you do not know their driving style. Once they have driven a few different set-ups, then it is easier to give them a base set-up. The reason I suggested what I did above for a base is because someone could be reading this that has never driven a Legends Car or any race car before and don't know their characteristics to begin with. Another reader could have experience with other chassis and decide to get to know these chassis. To get to know your driving style and reaction of these cars you have to set one up neutral and let the driver get the feel of the set-up neutral with change of driving style and go from there.
 Honestly, when someone contacts me for a set-up, first thing I will ask is their spring set-up. Once known,I will generally advise adjustments with those springs that they are used to. Goes back to how they are used to the car reacting. Let them run the chassis that way and learn from the change. Once they report back to me how the chassis reacted,I can identify their driving style and move them in the right direction from there. In the past I have given racers  kick butt set-ups and they couldn't drive it because of their style. Hence, once again why I have not blown a good base setup out there on this thread. There is no base established until driver ability is known.
At this point, I will ask if anyone even knows how they built the push into these chassis  ???

~Gimpster~

Offline justfreaky

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Re: Need a base point for set up on a 1/4 mile dirt track Please help
« Reply #18 on: July 19, 2013, 10:58:59 pm »
Gimpster,

Not worried about you being grouchy.  ;D
Seriously? So you are trying to say go to the track with the springs out of whack, set up way off base and let more air pressure out of the tire than you have in it? If you have no kind of baseline set up to compare to; You can adjust whatever you want, to no avail. Air pressure IS a fine tuning device. Since Tyler did not post his current set up and asked for anything, this is what I have that at least makes some kind of sense. Yes, what you are saying is somewhat correct. Air pressure does react on the chassis to some degree as you pointed out. But it is still a fine tuning device. But you bring up a lot about toe, camber and such also. That goes back to the original set up question. I don't have the perfect answer for Tyler, but I am trying to give him somewhere to start. All of this chassis set up goes back to all the basics in any chassis book. The basic set up is done long before you get to the track. Tire pressures are one of the basic 5 "at the track" tuning devices.

Tyler,

If you know what your set up is, that is great. If you can get a few of your local racers to share their set up with you, you can compare to where you are at.
Gimpster pretty much said all the same info as I posted for you to start with. I know Jeff did well with this set up as his basic starting point. You have to be in the ball park before you can play ball.

Steve
Better to be hated for who you are, Than to be loved for who you are not.

Gimpster

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Re: Need a base point for set up on a 1/4 mile dirt track Please help
« Reply #19 on: July 19, 2013, 11:15:12 pm »
 Air pressures would hold true if we were on BFG's.. I can see it that way, but measure a tire buy compressing it an inch on a scale as you would compressing a spring to find it's poundage. There is a BIG difference between an AR tire with 20 pounds of air as compared to the same tire with 5 pounds of air. YES you can go to a track with completely wrong springs and compensate with air pressure. Bleed offs on rims is more proof that air pressure is more than just fine tuning. Once the tire builds heat and pressure, they bleed off which would prevent you from making a spring change to compensate for classes that are not allowing bleeders in the same situation. Hopefully that set-up book is newer than the outdated Steve Smith Dwarf Car Technology book. Good base and explanations about things but specifics within it have changed per techno and more need be added to it on the techno aspect since it's printing way back when.
 If he would provide the set-up he was running I could advise a change for the 1/4 mile track. Still nobody has hinted to the knowledge of what they did to build a natural push in these chassis..

~Gimp~


Offline justfreaky

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Re: Need a base point for set up on a 1/4 mile dirt track Please help
« Reply #20 on: July 19, 2013, 11:29:02 pm »
To some extent air pressure can fix some ills. I love all this therory. Been there done that. Perhaps not in the same arenas as you. Set up at the shop at least gives one some baseline to adjust from. Most of these new guys and gals come in totally blind. A lot of them don't even know how to make adjustments on the car what-so-ever. They just want to race. Sorry if I anger you, but these are the people I most like to help. I have had many far surpass my experiences. Hell, some of them are teaching me new thoughts and ways of doing thing. Yep; I'm an old dog. I'm ok with that. But you can teach an old dog new tricks. ;)

Steve
Better to be hated for who you are, Than to be loved for who you are not.


Gimpster

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Re: Need a base point for set up on a 1/4 mile dirt track Please help
« Reply #21 on: July 19, 2013, 11:39:55 pm »
 Odd is how this fits into topic but it does, since you mention old dog and new tricks. Youth born around 1980 and on up have a section of their brain that evolved. In reality, the pea in the pea brain became bigger and they learn different than older folk. They even had to change the way they teach kids in schools these days. I ran across it while helping younger folks with set-ups, that you have to learn them about how to change things differently than how you just tell and old feller. Some time, I will turn you on to a link that will keep you pinned to your screen for 5 hours on that topic. But for now, I will say this. One of the things I mentioned on the base set-up cures the built in push. BTW, I do know what they did. Just trying to see who else know because it is relevant to the solution of change that need be from a 3/8th to 1/4 mile track

~Gimp~

Offline justfreaky

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Re: Need a base point for set up on a 1/4 mile dirt track Please help
« Reply #22 on: July 19, 2013, 11:48:26 pm »
Whatever Gregg
Better to be hated for who you are, Than to be loved for who you are not.


Gimpster

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Re: Need a base point for set up on a 1/4 mile dirt track Please help
« Reply #23 on: July 20, 2013, 11:29:31 pm »
Ok , ok... next time someone wants set-up help, I'll send them on the snipe hunt with a GPS
But I get to be the GPS.

~G~