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Title: BRET-TECH SET UP INFO Post by: rip|Bretware on January 15, 2010, 12:56:55 AM Schools back in session, with a new car it's a perfect time to learn.
The new cars base setup is very different than the f3000, At rest the car sits high at the rear and uses a softer rear spring vs the front to get weight to the rear tires under power. The f3000 car setup sits much closer to level at rest and uses a softer or equal front spring vs the rear, the front drops under braking. If you look at it the f3000 car while braking its similar to the FM at rest, and the FM under power is near the f3000 at rest. The following is a good starting point for most cars, except super high horsepower cars which require a soft rear spring. First set wing, find out what others are using or estimate based on track type and add a little extra rear. Now work on getting good heat in at least one front tire 90c, set all springs equal, and front anti roll to a medium setting, set rear ride height 1-2 cm higher in the rear. Run two laps and focus on how the the car acts in first and second gear corners where down force has little effect. If you still lack heat and the car was tight, soften the front spring and tighten rear anti-roll one click, keep going until you get weight on the front end. Once we have the heat we want to check all tire temps and do a pressure-camber adjustment. These settings should be checked whenever ending a run. Pressure-Camber adjustment Adjust camber until the inside of the tire is 5c hotter than the outside. Adjust tire temps until the middle temp is halfway between the inside and outside. These settings insure proper shape and contact area of the tire when the suspension collapses These setting are very fluid, and should be checked after every run. Now we can play with the anti-roll bars to dial in the balance and check the springs. If your car is not loose, tighten the rear bar until it is then back it off a little, this has a huge affect on the car, think of a chair with 4 legs, if you were to cut a half inch off one leg then push it to the floor, the leg on the opposite corner would come off the floor, this concept is everything in setup up a car. When we tighten the rear bar we prevent the wheel from moving up in the "wheel well" In a right hand turn if we don't cut a half inch off the chairs left rear leg, the right front right leg won't come off the ground. Front or back adjustments remember opposite corner has the opposite effect. Now we play with the front bar, notice how I didn't say adjust, we want to tighten the front bar to see if we can bring the hotter front tire closer to the other. If your bar is too tight the car with tend to get to the corner and not bite because it's preventing the body from rolling the weight needed, if the bar is to loose the car will get to the middle of the corner and trip over the front end, sometimes followed by snap loose. It's a tuff adjustment and works hand and hand with the rear bar. Now I mentioned that the anti-roll bars are used to check the spring. While adding bar can prevent bodyroll it's only done for fine adjustments because it's not independent, it forces it's affects on both wheels, you wouldn't want both rear wheels to act the same coming out of a corner, so if you find yourself maxing out your bar setting you may want to tighten your springs. If you look at your tire temps, and think about where your having problems on the track you only need to ask yourself, where, which tire, overloaded or underloaded. If you were to look after the race the best handling car will be the one with 4 tires closest to 90c, it would be using more grip without over working the tires. Knowing this next we want to work on the rear tire temps, we should have a car that is pretty good middle-in. This next part is tricky, we want to get some more weight to the rear tires exiting corners. What ever we do we want to keep about the same weight on the frontend, middle-in. The first thing to remember is if we soften the backend, we will get the short legged chair effect in the corners I talked about, so we know going in the rear bar is going to tighten to counter the chair effect. The other tool we have to keep the front weight is the front to back ride height differental, increase the split as needed. Soften the rear spring, and make some runs, watching the front tire temps to help make adjustments. Keep in mind is that if we soften the rear spring alot, We will end up with a very tight anti-roll bar and a rear suspension that is less independent, also as we soften the rear there is a good chance no matter what counter adjustments we make, in the middle of the corner we will loose some front weight as the rear suspension compresses, Soften the front bar a little to bring the weight to the front if helps the car in the middle, but not if it hurts entry. Ok, So where did I end up? Well, it pains me to say, but not too far from the default setup, Only alot softer springs all the way around and harder bars, NOT with a softer front spring than rear, It wasn't that the hard front spring was effectiog balance, it was that the car was sprung too hard all the way around and had no weight transfer. These tire temps RF90 LF83 RR 82 LR 80, tell me this car is ready to hunt. This is all based on the F3000 Lola but most applies to other rear wheel drive cars. Most racers new to sim racing find setting up the car confusing, while there are many guides and charts to assist you, It can be really hard to figure out where to start. Grabing a setup file from the server may help but be warned, many are funny at best and the ones that are first class may not work for you due to your controler settings. Stearing angle(reflection of steering senitivity), brake pressure(reflection of brake senitivity) , differntial lock (effected by accelarator senitivity) can all change the setup. Also depending on your driving style the weight transfer of the car will be at different points. An example is, if you were to drive my setup you will need to brake and accelerate at the same spots on the track as me or where and when the weight transfers be off. If you were to get on the gas too soon you will find the car pushes off the corner and if you drive in to deep it may feel loose. To adjust your setup you will need to be smooth on the track with no wheel spin, tire slide or lock up. You have got to hit your marks everytime, this will allow you to feel what the car is doing and keep you from overheating the tires, as soon as you overheat the tires you loose the feel of the car. Start with the basics, brakes, I have seen alot of new drivers have problems with the brake settings. Heat is most important when it comes to brakes, find the max brake temperature for the car your using, then open the air ducts to keep you below that tempature, over that and you will get brake fade. Next move the balance to the rear if you can without causing rear lock up. I always find the corner where the rearend is the lightest and dive in extra deep to check for rear lock up. This is an important setting because you may have to check up during the race harder than anytime in practice or qualifing. The last setting is the overall pressure, after your other setting are complete, if you get excessive front lockup, reduce pressure. Now we can work on the balance of the car, to achive this we need to stay on the racing line, if the car is evil you should add extra wing for now to help keep you on the racing line. We need to get an idea of what the tires are doing, we want to make sure they get enough weight to build temps, but not so much weight that the tires get deformed. I look for about 90c on the tires. Camber is an easy adjustment, we want 90c on the insides and about 5c less for the outsides, more camber increases the split, less decreases. Next use the air pressure to get the middle temps between the inner and outer. Body Roll is next, below is some info, I will be reworking it soon Anti roll bars and springs Springs allow movement, Anti roll bars restrict movement, shocks control movement.(Shocks will be covered at a later date) The Anti roll bars and springs help control the load given to each tire. While the spring can be adjusted to help keep the load on the tire at bumpy tracks, adjusting it changes the body roll in the corner. We want some body roll so we can distribute the amount of load to the tires that fully uses the tires abilitys, but doesn't overload them. Overloading results in high heat and tire deflection(loss of shape). We start with the springs, we want the springs hard to the point of, (1) We can get enough body roll to generate heat in the front tires (2) The car is comfortable over the bumps. After you have your spring setting, dial in the body roll with the anti roll bars. Anti roll bars are used to restrict body roll by preventing the wheel from moving up in the wheel well. Use your tire temps to dial in the roll bar, if a tire overheats reduce body roll. Lack of weight transfer will make the car feel like it's sliding on top of the track(not biteing into the track) Too much body roll will make the tire dig in and then slide as the tire changes shape. Note: 1) If you are sliding your tires in the corners the temps will be false. 2) Too much body roll in the rear will displace weight from the opposite front tire. Differential COAST The less coast the more weight the engine puts on the drivetrain, this makes the rear end less likily to follow the front wheels. Think of a boat with a line tied from the back to a dock, if you were to gun the boat and turn the wheel the boat would pivot it place. This is the effect we are looking for in the car, to the point where the weight of the motor dosen't break rear traction. Expect this setting to be between 20-65, you will find the low 20 setting good for low speed tight sections if other areas of the track will allow for this setting. POWER When exiting a corner it is common to get tire spin on the inside wheel because it has less weight on it, the diff lock can transfer this lost of power to the outside wheel by locking the rear end together. This can have a few draw backs. First while turning, the outside wheel is traveling a greater distance than the inside wheel, if the rear end is locked in this situation one wheel will be forced to break traction causing a loss of grip from this tire. Second in situations where you are too agressive on the gas a locked rear end will cause both tires to break free at the same time. The adjustment is in relation to the amount of torque being appllied by the engine, the highest setting locks the rear end with the lowest amount of torque, look for setting in the range of 10-40, maybe fully locked somewhere like the Indy oval. HOW TO ADJUST Lock, adjust up to correct inside wheel spin exiting corners, adjust down to correct snap loose on power. Coast is a little more tricky, because the rear wing and car balance has a big effect. The deeper you drive into the corner the softer your setting may need to be. Weight transfer is a big factor for this setting, the more weight that dives to the front the less traction the rear wheels will have. General rule is as low as you can go without causing looseness. Look for snap loose on entry just as the engine down shifts and the RPM's are high PRELOAD The rear end changes from power to coast when you press or release the gas. Preload adjust the abruptness of this change. WHEN TO ADJUST Adjust up only for problems that occur just as you press or release the gas "quicky". Use to correct looseness into fast corners just as you lift and snap loose on thoddle. Preload requires power and coast to be set and reasonable, all differential settings require well set up suspension, wings and ride heights to dial in. Title: Re: BRET-TECH SET UP INFO Post by: rip|ChITty on January 15, 2010, 10:01:43 AM Where was this info before?! I might have had a shot at the championship ;) :P This encourages me to play with the coast, I've pretty much always left it at default and only played with the lock/power. I know these are probably stupid settings, but for Watkins I was using a 20% lock or power and 45% for coast. Title: Re: BRET-TECH SET UP INFO Post by: rip|buzinator on January 15, 2010, 10:06:21 AM 10% Lock and 65% Coast @ The Glen for me.
Preload was at 2. Title: Re: BRET-TECH SET UP INFO Post by: rip|Bretware on January 16, 2010, 04:09:32 PM At 20% lock, adjust up to correct inside wheel spin exiting corners, adjust down to correct loose on power.
Coast is a little more tricky, because the rear wing and car balance has a big effect. The deeper you drive into the corner the softer your setting may need to be. Weight transfer is a big factor for this setting, the more weight that dives to the front the less traction the rear wheels will have. General rule is as low as you can go without causing looseness. Look for snap loose on entry just as the engine down shifts and the RPM's are high Title: Re: BRET-TECH SET UP INFO Post by: rip|Bretware on February 22, 2010, 03:10:33 PM Added roll bar and springs, expect changes
Title: Re: BRET-TECH SET UP INFO Post by: rip|Bretware on March 25, 2010, 07:16:24 PM Added some stuff
Title: Re: BRET-TECH SET UP INFO Post by: rip|Bretware on November 26, 2010, 08:33:32 PM updated
Title: Re: BRET-TECH SET UP INFO Post by: rip|Bretware on November 28, 2010, 10:48:02 PM I fixed the part about guessing when you first set your wings, lol.
Estimate, would be a better word for the concept. Title: Re: BRET-TECH SET UP INFO Post by: rip|Bretware on December 04, 2010, 10:26:52 PM I updated the FM setup instructions to give you guys a chance on Tuesday ;D
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