Hi All, Just took my 355B out for a spirited drive - but my experience wasn't what I expected. At full throttle the nose becomes very light and the car moves around a lot. The steering becomes very light too, to the point where I had to back off the throttle as it was too disconcerting. Is this normal?
I had similar problem and the sway bar was disconnected on the drivers side. Maybe you should check your aligment or suspension components.
I would guess the first place to start is verify ride height and alignment are correct. I've never experienced this but the fastest I've been is the top of 5th. What speed are you having issues?
Agree with the above comments. Never had such an issue but those would be a good place to start. As FBB said those bushings are old.
It was a common complaint when the cars were new. We dropped the nose on a lot of them by about 1/2 an inch and we were told by the owners it cured the problem.
Thanks for all the replies. I have been considering lowering the car (and replacing springs with challenge versions) and replacing the anti-roll bars for Fiorano items. I'll get the car on a ramp in the next few weeks and see if the bushes seem particularly worn; either way, I may as well replace them too.
Cars with areo are much more sensitive to ride heights than crs without. As little as 2mm in ride height change can turn an uncontrollable car into a planted car. I suspect that no suspension spring on any F355 is within 2mm of when the car left the factory.
Not sure my car is as bad as what you describe but it most certainly gets light in the front at upper speeds. I'll likely replace tires next year (time based) and will trailer the car to Scuderia Performante and have them check out the alignment.
Mine is definately not planted at top speed but is managable. It moves around a little and of course is touchy on the steering. I assumed the road was not flat and the car is fighting the wheel ruts from the traffic. Up to 150 or top of 5th it seems very planted.
Amazing, all the Ferrari pundits claimed the 348 handling sucked. I thought the F355 was huge improvement over the 348?
If you're doing a suspension upgrade and want a streetable F355, consider getting Fiorano springs or Delta Vee's equivalents to go along with the Fiorano anti-roll bars. The Challenge springs ideally require further modification of your suspension and if you have a 1995 car, the front shock mounts will have to be reinforced. That would yield a trackable car which will be a pleasure on the track but not very comfortable on the roads. In either case, ride height and alignment will need to be done. Good advice was given here:
No, Ferrari designed a car to pass all bumper crash and height restrictions world wide and all headlight height restrictions world wide. High speed stability considerations were secondary.
So the touted 1800 hours of wind tunnel testing were just for promotion? Luca: "We spent 1800 hours of testing to get the aero on the 355 right and have eff it 'cause the bumper is too low?" Marketing: "Yea, but we can use it to promote the car." Luca: "Great idea. Let's raise the price another 10%."
This is something I have never thought about...what roads was the 355 originally designed for? Are there "eurpopean" alignment settings that completely change the character of the car? In the USA I can only assume american cars are designed for american roads and bumper heights. On the modern vettes we race in near stock classes we have very limited lowering because we run out of shock travel. The cars are actually faster at near factory ride heights. GM designed the vette right because at factory rake and near factory rideheight even with tow out in the front we are rock solid at 160mph which is top speed at Daytona on DOT-R race tires. GM seemed to properly design the vette for it's entire performance envelope even though the top road speed in the USA is 70mph. Maybe Mitch or Barry who track their 355's might comment on "track" 355 ride heights, chassis rake and alignment? RD's 1/2" front drop is a lot of chassis rake change and a lot of lost shock travel. If for example dropping 1/2" is needed to alter the chassis rake for high speeds and the combo of huge huge front 355C springs additionally negate the loss of 1/2" of shock travel, and who knows what effect on bump steer, that would be an amazing set of suspension compromises and lend credence to JohnK's statement of Ferrari getting it wrong.
I've attached my F355 Challenge Alignment print-out. Caster is factory spec. Remember this is a Challenge alignment. Springs: 2200 lb/in F 900 lb/in R Ride Height: 90 mm F 95 mm R Measurements are taken from the bottom of the chassis, just behind the front wheel centerline and just ahead of the rear wheel centerline, not including the undertray. Cross weight must be within 10 pounds with driver and 1/2 tank fuel. See Rob Schermerhorn's blog on Delta Vee for further discussion of varying chassis rake: Set-Up F355 Challenge for Racing . Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Thanks for all the help. I managed to get the car on the ramp for 5 minutes just to see if there was anything obvious. The passenger side of the car is sitting 10 mm higher than the drivers side; this must get exaggerated once the driver is inside.
