| Author | Message | ||
| Gregg Willhoit (Gregg)
New member Username: Gregg Post Number: 4 Registered: 5-2003 |
Mitch, Thanks for the suspension tuning information. I've printed it off, and I will give it a try. I'll let you know how the adjustments affect the oversteer. | ||
| Mitch Alsup (Mitch_alsup)
Member Username: Mitch_alsup Post Number: 653 Registered: 4-2002 |
I should add that you should do this setup with 1/2 a tank of gas, and the drivers weight in the drivers seat for both corner weighting and ride height setting. | ||
| Mitch Alsup (Mitch_alsup)
Member Username: Mitch_alsup Post Number: 652 Registered: 4-2002 |
Greg: with regard to oversteer. My F355B came with a lot of oversteer (two kinds). I played around with camber and toe until I was blue in the face without much luck. I could feel each change in camber or toe, but I never felt I was getting ahead of the problem; and in my case there were two issues. Issue one: car had the tendency to go directly into oversteer while trail braking into turns at the onset of steering input, and displayed instability when braking from ultra high speeds in straight line. Solution raise nose 2 turns. Issue two: car would oversteer under power exiting turns. This ended up being a lot of fun. But I wanted better traction in this department. Lowering the tail solved this problem and all was well. Basically, this reset the rake of the chassis. The rake of the chassis and the roll centers of the suspension can be used to fine tune the spring and anti-roll bar package already on the car to achieve whatever kind of balance the dirver desires. Raising the nose moves the front roll center and decreases the lever arm at the front, increasing the effective stiffness of the spring/roll-bar package to roll while leaving the same spring rate with respect to bump. Lowering the rear does the same in reverse. So changing the rake of the chassis can be used to adjust the roll couple distribution front and rear. The changes are basically invisible as seen from a few feet away, but the sensitivity of the F355 to suspension adjustments is very high. I can now run 35F/35R tire pressures and have a completely neutral car both on the road and on the track. These adjustments took 25 degrees of tire temperature off the rear tires (TWS with probe pyrometer) and completely changed the characteristics with respect to throwing the car around and having confidence of its response. Factory 355 alignments: Front camber -0.5 to -0.8 Front Caster 7 Front toe in 2mm +/- 0.5mm Front ride height 163mm Rear camber -2.0 Read Toe in 2mm Rear Ride height 187 mm Ride height is measured at the centerline of the pivot bolt on the chassis bracket at the back of the lower control arm to the (flat and level) ground with tires at HOT pressures. My car was only 4mm low (1/8") at the front and only 2mm high (1/16") at the rear. But this adjustment really transformed the car. Anytime you move the adjustment collars you should also be performing a corner weighting. Good luck | ||
| DES (Sickspeed)
Advanced Member Username: Sickspeed Post Number: 4055 Registered: 8-2002 |
i think it's pretty sweet...! Nice car, Gregg... & you're just looking for trouble parking it between two Porsches... Friends of yours...? i bet those 3 cars make for some fun drives... | ||
| Jim Schad (Jim_schad)
Intermediate Member Username: Jim_schad Post Number: 1265 Registered: 7-2002 |
I know that color is not the most popular, but it is really growing on me. | ||
| Gregg Willhoit (Gregg)
New member Username: Gregg Post Number: 3 Registered: 5-2003 |
Here is a pic. Thanks Sickspeed!  | ||
| DES (Sickspeed)
Advanced Member Username: Sickspeed Post Number: 4026 Registered: 8-2002 |
Gregg, welcome to FerrariChat...! How about a picture of that beautiful 355...?  | ||
| Gregg Willhoit (Gregg)
New member Username: Gregg Post Number: 2 Registered: 5-2003 |
Thanks for the Texas welcome Dave, Jim and Jayson! Jim, I was lucky to get Rosso Barchetta as I wanted an F-car so bad, I would have taken "burnt orange" if they had it.<gr> Jason, I live close to Kirby and 59, north of 59, some people refer to it as the "Upper Kirby District" | ||
| Jason Williams (Pristines4)
Member Username: Pristines4 Post Number: 288 Registered: 12-2002 |
Howdy Gregg, Which part of Houston are you in? I'm down in Clear Lake next to NASA. | ||
| Jim E (Jimpo1)
Intermediate Member Username: Jimpo1 Post Number: 1785 Registered: 7-2001 |
Greg, you have my car! My next Ferrari will be one just like yours, although I was thinking I might get the Crema interior. I love Rosso Barchetta. Welcome aboard! | ||
| Dave (Maranelloman)
Intermediate Member Username: Maranelloman Post Number: 1552 Registered: 1-2002 |
Welcome, fellow Texan!! | ||
| Gregg Willhoit (Gregg)
New member Username: Gregg Post Number: 1 Registered: 5-2003 |
Hi, I'm Gregg Willhoit. Have a 355 Spider, rossa barchetta/tan/6spd/tubi. I'm impressed by the depth/breadth of Ferrari knowledge on this board. Just in the short time I've been watching, I've learned how to reset my ECU, why 2nd gear is kinda recalcitrant when cold, EVERYONE seems to have some sort of manifold/cat problem (FOH said my manifold problem not severe enough yet), the black gummy plastic pieces are not just my problem(whew!), and a few other useful tidbits of Ferrari technical minutiae. I'm considering getting larger tires in the rear, as I'm a little surprised by the amount of oversteer(I have a 97 RUF Cabriolet that is supposed to have lots and does). Anyway, just wanted to introduce myself, and say hello. I'm interested in meeting some of the local F-car owners. I'll be on the look out for upcoming social (yes I imbibe..I'm a functional wino<gr>) events. Look forward to meeting ya'll, Gregg |