Need a base point for set up on a 1/4 mile dirt track Please help

[TylerS14]

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.

[justfreaky]

Hi Tyler,

Welcome to LegendsRacer!
Try this thread. Should give you a starting point.
http://www.legendsracer.com/index.php?topic=2371.0

Steve

[TylerS14]

Thank you this looks like a good starting point.

[justfreaky]

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

[canabl]

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.

[TylerS14]

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.

[Earnst85]

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.

[justfreaky]

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

[TylerS14]

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.

[justfreaky]

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

[canabl]

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.

[VMS Motorsports]

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

[justfreaky]

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

[djracing]

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.

[justfreaky]

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