LegendsRacer - Legends & Bandolero Racing Forum
LEGENDS => Setup and Handling => Topic started by: TylerS14 on July 14, 2013, 04:22:23 pm
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Hi I am new to the legends. I have a friend that has ran one all year now in eastern PA. He had a coupe and now he bought a sedan. I run a 4cyl. mustang thunder car and now I am going to run my friends coupe for one race [ possibly more]. The problem is my buddy doesn't seem to have a good set up for his car and I have no clue. I am running the car at the same track that I run my thunder car so I know the track and I run very well there. Its a 1/4 mile semi banked dirt track. I need a good starting point. [ springs, air pressure frame heights]. I would appreciate any help.
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Hi Tyler,
Welcome to LegendsRacer!
Try this thread. Should give you a starting point.
http://www.legendsracer.com/index.php?topic=2371.0
Steve
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Thank you this looks like a good starting point.
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You will still need to adjust for your track and driving style. At least it is a starting point.
Not sure what you have now.
Steve
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What tyres are being used by you boys in USA?
We running American racer sd57 USLC series tyres.
We find on a clay track, we running lower pressures, most guys start off,
FL FR
8 8
RL RR
6 8
Usually dropping a pound all round for second heat then another pound all round for feature.
I run the same setup thats detailed in that link and apart from tightening the car up a few turns on the left rear, the car is a dream to drive with limited experience.
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Yea I was wondering the same thing. Is that link from when they were on the BFGs or the race rubber? and was this from when you were not allowed to run a bead lock on the RR.
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Its hard to give you a specific air pressure for each corner. Just to give you an idea, I run run completely different airs between my 2 cars. My base set for the primary car (woody) is RR 12 RF 11 LR 6 LF 10. The backup car (what I run at Linda's) is RR 10 RF 11 LR 5 LF 7. These where established based on scale readings in order to get closer to the cross I wanted. With that said, I know of other guys running 6-8 lbs in the RR. My advice would be to scale out the car with you in it and adjust air to what ever cross you are looking for. I would also tell you to try the setup Keith had been running on it and adjust after each time you hit the track. I should be there friday and can help you guys with adjustments. Just a heads up, the rear ends gonna come around alot quicker than your charger. With the shorter wheelbase & power to weight difference your gonna be all smiles.
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Air pressure is just a small part of the set up. More a fine tuning adjustment.
I do believe Jeff posted this set up using the old BFG's.
Steve
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Thanks everyone for the input its a big help. I think the last question I have is on my car I run tubes in all my tires because I cant run bead locks. But I notice that my buddy doesn't run them. With the low pressures I would think you should run them in the three non bead lock wheels. Are tubes common in the legends or am I thinking about this wrong.
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With pressures as low as Adam is talking, Tubes are probably a good idea.
I still think the set up that Jeff posted would be a good place to start. It will take more than one race to get things adjusted to your track and driving style. If you have a practice day, or can get there early and get some time for practice; So much the better. As you don't think the set up is good "as is", then I would set up the car with Jeff's suggestions as a baseline. You will still need to do some fooling around to find out what works for you.
Steve
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We run a beadlock (mandatory) on RR only. have seen pressures as low as 4 on our LR and 6 up front, even after getting king hit on the rim and tyres we have never seen a bead let go.
We also scaled the car with the tyre pressure i noted above and good clearance but now going into the new 2013 chassis, we have found the car stiff and testing this weekend at our local track to see if our cross is too high making the car feel loose on exit or if the new 1250 motor is making us break loose over the stock 1200 we recently ran.
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I've been playing with tire pressures since the AR's hit the scene trying to find what works best for me.
Currently running (on a dry-slick high banked 1/3 mile):
LF 8 RF 10
LR 7 RR 9
...and it's the best I've ever run, but I also changed the set-up quite a bit.
So many other things play into it. You just have to play around and see what works best for you
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As Jim said; " You are just going to have to play around with it". Chassis set up is not all about tire pressure.
If you seriously have no baseline set up, start with Jeff's set up. At least you will have something to start with. Keep set up sheet and lots of notes about what you change, track conditions, etc... You do have to start somewhere. ;)
Steve
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Alot of races last year
LF 10.5 RF 13
LR 7.5 RR 10.5-12
Cross would be in the range of 47-48% and 2-3 inches rear stagger. Car never had an issue turning :)
Edit:
Springs
LF 190 RF 190
LR 150 RR 140
Car only weighed about 1315 before a feature. (driver weight 165 with gear) Had max left side and rear weight rules allowed. Front camber/caster similar but not the same to Jeffs setup.
Ride heights
LF 4 RF 4.125
LR 4.25 RR 4.5
Toe 1/8 - 1/4 inch.
Rear end was squared to the front shock towers.
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Why is everyone so stuck on tire pressures?
Tire pressure is a fine tuning adjustment.
Hell run 1 lb. if it makes you happy. Without some baseline set up, what are you going to compare it to?
Seriously?!!!!!!
Steve
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( 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~
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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
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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~
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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
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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~
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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
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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~
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Whatever Gregg
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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~