Keep it totally streetable but get rid of the snap oversteer on track

What alignment are you currently running? We're your offs because of trail braking, hitting an early apex and running out of room, or something else?

 

I believe throttle control is very different between a front engined car and a mid-engined car like the F360 ... thus with some time to allow you to change habits surely this issue would be somewhat resolved?

My point is not all cars behave the same to the same inputs and YOU need to adapt.
Pete

 

I'm running -2F/-2.5R with some toe in the rear... Seems that is what most folks are happy with.. Car is a bit lower than stock, but I'm not sure how much (previous owner was responsible) I can compare measurements if you want. I have only a little seat time to compare, but I've been able to control high speed traction loss and keep it moving the direction I want - 2 times above 80mph I had the rear break on me and I had time to respond.. No snap. Regardless of the setup, I think the weight balance is controllable, but smoother, and keeping the weight neutral or on the back tires in corners will keep things happier . Traction control in sport I assume? Tires? Did you watch tire pressures?

 

Fair comment but I did have to adapt my driving style with the last club car I built and raced.

Good luck
Pete

 

Funny you say that about the brakes - I've been dealing with that, and now have a front bbk on the way.

Would be curious what others have to say. I don't know that track at all, but 140mph corner speed is no joke...

 

Does a Stradale count?

My mount was twitchy to the point that it felt like I was going to go off at any moment when I 1st tried it. But it never actually got this out of hand. Anyhow I made several trips to the alignment rack & finally came off of it with cornering prowess that matches the hype.

It did take gobs of negative camber, and toe in at the rear (more than I thought it would). Its just plain impressive now.

I can still step the rear out when pushed, but the damn thing goes where its pointed - competently.

Get on that alignment & invest in a more track oriented tire.

One last note. These cars roll too much (just look at your photo). I would bet on a larger set of anti-sway bars if I wanted to continue to tune my setup (but for now I am pleased).

 

Michael - What settings did you finally settle on?
Like I said, I'm at -2 and -2.5, and then a total of .5deg of total toe in the rear.

 

Can you give us a print out of what alignment was used on your car so we know where to start? Thank you

 

Ok, brakes could feel good, but your crazy fluid boiled! Sucks to get to a corner and have the pedal hit the floor. I know!

Your spin at corner 17 sounds like you were asking a lot of the car, scrubbing a fair amount of speed some of which was after turn-in. Throw up the video if you have it!

 

Certainly,

Looks like (have last printout here) Front= Caster 7.2 / Camber -3.1 / Toe 0 ~ Rear = Camber - 2.55 / Toe-in .20" each

I started with F430GT recommendations & went from there until I was content (but not done yet!).

Yeah, with that much roll the negative camber really comes into play.

 

Did you reach down to change gears (manual?) right as you turned in? Almost looks like that's what upset the stability.

I changed my fluid too, helped but didn't resolve completely for me. Hopefully you are good. I came to the conclusion, right or not, that the fronts are just a little small for my use of the car (longer braking than a more experienced driver), and hot enough to do nasty things.

 

I'm using carbotech xp10 front xp8 rear... Was going to move up to xp10/10 or xp12/10 for better bite & consistency, but now with the larger fronts, I'm going to try xp10/10. With this setups it looked like 1/3 or 1/4 use in a track day... But that's going to vary a lot. Hopefully you can get by with new fluid, I boiled it with brand new motul rbf600... Melted the dust boots, burned the paint off of the pads, etc. Pads didn't fade much if at all.

Downshifts can definitely benefit from some heel/toe... And without care really can jerk traction away from you...

btw, your car looks great out there (already pretty low?)

Sorry, just looked at my sheet. I'm at -2.5F and -2R. So, Michael is running just a little more F and R.

 

Thank you very much for posting these specs Michael. I'm going to have my CS adjusted to these specs and see how the work at Spring Mountain in Sept.

cheers!

 

ouch, kinda harsh no? PSK was just trying to help as you make many comparisons to your M3 (another fantastic car in it's own right for sure).

anyway....good luck brotha. Nice to see another fcar on track.

 

There are too many factors at play.

1) How old are the tires? If older than 4 years or heat cycled out, they are not track worthy. Sebring does not forgive old tires, I have witnessed plenty of cars finished there.
2) What is the specific tire model (there are many series of Michelin Pilot)?
3) A 360 Modena will surely not reach 140mph before T17 at Sebring, much less with a 150-200 lbs ballast sitting as an instructor. All the speedometers in almost every Ferrari are inaccurate by a large margin. The error increases with speed, because it is proportional. For instance, a car showing 110 mph on the speedo, while indicating 100mph on the GPS will shows 220mph on speedo at 200mph.
4) The GPS speed is very precise, from a navigation system, Harry's Lap Timer on an iPhone, and Android Phone, or a decent data acquisition system.
5) YellowStuff pads are garbage and should never be used on a racetrack. Pagid, Endless, PFC, Carbotech, Cobalt make great track brake pads.
6) It is good to know what kind of brake fluid was replaced in the system.

By looking at the video, and the steering angle (almost straight), that's a very little angle to produce a spin. The car is either suffering from an ill alignment, heat cycled out tires or bump steer on the rear axle. There are no bumps at the end of the back straight entering T17, but the picture shows a lowered car, so bump steer is still a problem.

The 360 is very easy to align, if you plan on tracking the Modena some more, the car will need stiffer springs, bigger front brakes, and brake cooling ducts. I like the Pagid RS19 or RS29 pads for combined street/track use, I even use RS19 on my SUV (better for towing when brakes are critical).

For track use, I would get a 2nd set of wheels and fit tires that are suitable for track use, many affordable options available. This will eliminate the tire age problem.

Florida weather (hot and humid) presents high stress on the engine, transmission, brakes, clutch, as things run hot in here. With decent driving skills, the stock Modena brakes won't tolerate Sebring not even with good pads, good brake fluid, and brake cooling ducts. This car really needs a big brake kit.

No idea on what lap times the HLT iPhone app was reporting, but based on the 2:34 by the end of the straight barrier between T16 and T17, and the actual top speed shown (126mph which is decent for a 360 Modena on pure street tires), the lap times must have been in the 2:45 to 3:00 minutes range. At this pace, there is no need to change the brake system, just add cooling ducts, good brake pads, good brake fluid.

360/F430/16M/Scuderia/Stradale share a lot of the basic suspension geometry, and they have similar weight distribution.

Feel free to stop by an alignment shop (GoodYear store), and ask them to connect the sensors from their alignment equipment, and get a read-out of the alignment the car has right now, I bet it is messed up badly. Get a print out from them. It should cost no more than $50 (don't do the alignment, just get the reading in print). Also measure the ride height from the front and the back on the side rocker panels (4 corners), I can extrapolate to height from the suspension measuring points if you provide the tire model, their tread depth, and inflate them in between 30psi and 40psi.

The measuring point for the suspension is easy to reach when the car is on the alignment bridge (Front is chassis from the back section of the lower control arm, Rear is chassis from the front section of the lower control arm).

A friend went emotional and brought his Stradale to a racetrack, despite of my advice to change the tires, brake pads, brake fluid, alignment, ride height and corner weights. He totaled the car, the car did a snap oversteer on turn exit and hit the wall, he is an experienced track driver.

The expenses are pretty low to make a Modena track-friendly, and a 360 Modena with a manual transmission must be one of the must fun cars (not the fastest) out there.

 

The critical alignment setting in these cars (360/F430) is rear toe. Be sure you're using 0.25 degrees toe-in per rear corner (0.50 degrees total).

Some shops use minutes to measure angles, rather than degrees.

20' (20 minutes) per rear corner is too much toe-in.

60' = 1 degree
20' = 0.333 degrees (it would put total toe-in to 0.67 degrees, way too much).

To achieve 0.25 degrees per rear wheel, (15' per rear wheel), you can also use millimeters. 4mm total toe-in will produce the 0.50 degrees total toe-in.

Front toe is good at zero, or just a little toe-in for comfort on the streets and high speed (0.10 degrees per wheel), or a little toe-out for autoX and twisty race tracks (0.10 degrees per wheel).

Camber is determined by the tires used. -2.0 degrees all-around is fine for street tires. -2.5 degrees all-around is fine for combined track/street use. These are initial settings, as camber needs to be fine tuned for the tires being used, car weight, driving skills, racetrack, etc, many factors.

 

The alignment is pretty decent. I would recommend you:

Front: -2.5 camber, 0 toe
Rear: -2.5 degrees camber, 0.50 degrees total toe-in (0.25 degrees per corner)

From the front and rear ride height measuring points: 120mm front, 140mm rear. If you can run stiffer springs, then set it down to 110mm front and 130mm rear. Below this ride height, or running this ride height with racing tires, the car will hit the bump stops, and handling suffers badly when you ride the bump stops.

 

Thanks, I actually am at -2.5F and -2R. I had it switched around. And the toe you suggest. What are the measuring points you mention?

Also, I really am curious what solution you've seen/used for brake ducts. (Like really interested in detail!!) And how the challenge carbon deal might bolt up and work or not.