Project Update
I've done much testing of various set ups at various tracks. I've done my own tweaking and tuning trying to get this Bird as fast as she can be. What a daunting task as this beast has various tuning challenges. As you begin to address one issue you inadvertently create another. Then you get lost in curing all the issues. Another thing I've noticed is that consistency when testing this car is incredibly difficult. I've found myself making incredible fast laps but unable to repeat the time consistently, and settings that would churn hot laps, they would churn a hot lap when finally contained and dancing on the edge of disaster the whole way through, a dance that is difficult to repeat with precision. It would seem that to accomplish my Project goal, I may have to settle for a car that was not the absolute fastest, but the most balanced and consistent. At the same time I can't completely tame the Beast, she still needs to be able to bite, but on demand.
I figured the biggest issue to address first and what would be impossible to overlook, was the incredible off balanced weight. The heavy rear end coupled with the earth shattering torque put out by the rear wheels makes for a touchy throttle pedal. Any tuning around such an offset weight/huge amount of torque would be an exercise in compromise in an attempt to contain the back end. It's basically like driving a hammer with the front end being the handle. When you hit a corner the heavy side always wants to go around the light side, as if you threw the hammer. In the case of the CTR this is the rear end swinging around the front wheels. I made many attempts to tune the suspension as is, but it became more and more apparent that the weight needs to be equalized before we can address the suspension tuning.
I began making some calculations to see how much weight was being tossed around and how much the balance was upset as it moved around. This was a great move because it showed me just how serious the Problem is. The front and rear weight balances are so far apart when weight is transferred that while looking at how loaded the tires are during braking/acceleration and cornering it was all too clear what needed to be done. Ballast, this would be the only way to balance the weight and establish the best starting point for tuning. According to my calculations we were looking at a need for close to 200kg of ballast on the front end to even out the weight. Now some people don't like the ballast because it does slow the car down, however when needed if done right it can be the answer to our problems. Seeing that there was a need for 200kg upfront I began making some other calculations based on some recent findings in regards to ballast. Some believe that when moving the ballast position you at the same time move the weight of the gas tank, or a 100kg of stock mass is moved with the ballast tank behind the scenes. When considering this if at position 0 there is 100kg behind the scene weight split between the front and back, then moving it in any direction will add 50kg in the direction you move it while taking 50kg off the other. So moving the ballast tank with nothing in it added 50kg to the front and took 50kg off the rear, after readjusting my calculations to account for this and the amount of weight transfer the new amount of ballast needed became 130kg up front approximately. So I toss 130kg and do some testing. The place I go is Eigar Nordwand because of that huge jump at the start. If I got an overly heavy side I should see some dip on the heavy side when in the air. I get the car air born, and she stays perfectly level and lands on all 4s.
With good often comes bad. So after I've been able to relatively balance the weight, I created a much heavier front end that doesn't want to go around corners. What?!?!? A Yellowbird that understeers? Yeah, until you hit the gas too hard and break out the rear end that just whips around the front. So now I've created more issues, just great. Well actually, it was pretty great. Yes I generated more issues to solve, however all of a sudden proper tuning techniques to address the issues with the suspension began to work, I also started seeing real consistency.
I decided to fully address the suspension at this point, I needed to put the huge torque causing throttle oversteer on the back burner until the suspension was balanced. I'll deal with the torque through gearing and LSD tuning. I figure when the suspension is in check the power would be easier to deal with. To do this I chocked the crap out of the motor until it was hard to break the tail end loose no matter how much throttle I gave. I then went all out on the suspension until I was satisfied I had it dialled in right.
Once I felt the suspension was in check, it was time to turn on the heat and unleash the 610ft-lb of Torque. Instantly it was more manageable with the suspension dialled in, I did need to tweak it to accommodate the new power but tuning this car at this point became easy. Gearing was a breeze; the only issue left at this point was the LSD.
The LSD was the touchiest area of the Tune, dialling it in right basically took much trial and error balancing the Initial Torque & Accel, while the Decel was a breeze. I spent many hours last night and this morning working on this, I felt it was dialled in on a 1:04.8XX lap at Eigar Nordwand. The car is set up and ready for testing.
I bring this set up over to multiple tracks, TGTT, Grand Valley, Suzuka, Fuji, and put down fast consistent laps, lap after lap. They are not as fast as I was able to get on more unstable configurations, but I'm running sick fast laps with consistency within tenths lap to lap, with the extra baggage...
The Decision has been made, Time to Paint the Yellow Bird Black....
I havent Tuned the Bird to be the fastes she can be. Through my testing I found that the fastest laps with this car come out of the most unstable settings and consistency with them is near non existant lap to lap. What I've done is tune the Bird to be more, balanced, Driver friendly, & consistant from lap to lap. While at the same time retaining the Character of the "YellowBird" in stock form where she can break the rear loose in a controled manner for "Fun" driving. I believe I've acomplished this, and the settings I will release I feel truely embody what the Project intended to acheive.
Stay Tuned for more details, a video of the Lap at Eigar Nordwand & the Reveling of the Settings.
