348 at high speed

I did some spirited driving yesterday in my 94 348 Spyder and noticed at higher speeds 120+ the car gets very floaty on the road. What is the best way to rectify this? If I lower the car by adjusting the coil overs will this help?

Thanks,

Rob

 

In my experience.....a splitter of 1.5" or more on the front eliminates enough lift to cure this floatiness. Wheel spacers, etc, will increase stability, but will not reduce the air under the front, which is the cause of the floatiness, so put on a splitter. Easy to make, or use the SS lip commercially available. Lowering the front may help, but you'll scrape the front even worse on driveways, etc.

 

+1 on the splitter. I added the carbon fiber SS splitter and have seen speeds of 160MPH. I did not notice any "float". In fact, she handled very well and I would say that she was quite stable at high speed. I added the 25mm rear spacers last week and it made a huge difference in cornering stability. Before I could kick out the rear quite easily. Now I have to really work at it.

 

I think I want to add a front splitter at some stage, my car gets floaty at front above 120-130mph.

 

I guess your cars have the factory fitted chin spoiler part #27 on this drawing http://www.ricambiamerica.com/images/diagrams/full/348_124.jpg and http://www.ricambiamerica.com/product_info.php?products_id=236786 ?

Haven't had probs either on the road or on tracks at speed. with my Spider.

 

120+mph you say? Can 348s do over 120mph?

 

Please give more detail "splitter of 1.5" " ?? Photo ?? - I am familiar with the SS lip but you have confused me.

On track, I routinely cross the 130's and have only had the floaty sensation on "windy" days. Many people have stated similar feelings. I honestly think they are just repeating what they have heard from others, but that is another story.

Everyone needs to remember that a car moving 100 mph versus 140 mph is naturally going to feel different ( unless it has F1 wings / difusers and tons of downforce ) The amount if experience people have at these speeds is far less.

That being said, whatever this "spliiter" is please share more information. I would love to have complete confidence all the way up to the 160's - just need a longer back straight.


David C.



P.S. RHUNT and others - no offense intended - I personally have not had the "floaty" problem - every car and driver are different. Whatever keeps it safe is best.

 

No offense taken. You are absolutely correct...Having raced and gone to a few driving schools I am on the other end of the spectrum however. As we all know the art of driving fast lies in the seat of your pants.. LOL.... Experience is the only teacher. IMO...splitters work. F-40's have them, 512TR, 348SS, 550, etc.. My car feels more stable at speed after adding the splitter. It wasn't bad before, other than the oversteer while cornering that the spacers corrected, but after adding it the car settles down more in a noticeable way.


Just my .02...

 

171 mph was the top speed according to Ferrari. I am guessing the true speed in 165 factoring in the optimistic speedo. I have taken it slightly above 140mph myself.

 

I was kidding Trying to get into the spirit of things in the 348 V 355 wars



















































So the top end of a 348 need not have the 308 guys, let alone the 355 guys worried then

 

No one has spoken here about basics.

#1 - Tire pressures: Set to specs?
#2 - Tire condition: Normal wear pattern, legal tread?
#3 - Tire rotation: If your tires have directional tread, are they turning in the correct direction?
#4 - Tire matching: Are all four the same brand and model, or do you have a mixed set?
#5 - Tire speed rating: Are you sure that your tires have a "Z" speed rating?
#6 - Wheel alignment: Has the front and rear alignment been checked and set by someone who knows what he is doing?

Anything else? Personally, I have never driven my 348 over 110mph, so I'm not an expert on high-speed characteristics.

 

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I check tire pressure and condition before every drive. Through racing I learned how important your tires are. And at extreme speeds (anything above 100MPH IMO) your tires are your only contact with the earth..

What about the loose nut behind the wheel?

 

Someone get a rope... LOL!!

 

I haven't read about it in the past, I was comparing it to how my NSX feels at high speed. I topped the car out and it was actually scarry at 140 and above. Please don't take this as me comparing the 2 cars, but I just want to get the car a bit more stable at high speeds.

 

I have found there to be a few issues to address on these cars with respect to higher speed stability.

1st is the tire size. Essentially, the 348 stock wheels suck unless you space out the rears with Ricambi's 25mm spacers. Tires are getting harder to source for stock 348 wheels and the best brands require either mixing models to get the stock size or changing the front to a close size. You don't want to mess with the rears unless you don't mind speedo error. For example, I chose Yokohamas on my Spider and took a smaller profile up front in favor of stock in the rear. Yep, it dropped the car slightly up front too for better air flow.

2nd is to replace the 348 stock wheels with 355 shoes - this worked great on my SS - with smaller spacers (15mm) on the rears. You also get more choices of tires. I have Pirellis but am lusting for Michelin Pilot Sports.

3rd is to add a front chin spoiler to the lower valance as mentioned above. The trade off is the inevitable damage you will suffer when you "forget" just how much clearance you have up there, especially if you lower the front tire profile.

4th is to adjust your ride height which is an interative process. For example, I need to lower my rears, but then the fronts will be higher, so I might need to adjust them too.

Lastly, whatever you do, don't forget to have the car aligned. You can dial out the floatiness in the front, but remember that you can inadvertently dial it into the rear. The key is balance, neutral handling at speed. With a mid-engined Ferrari, that's quite a task so just shoot to make it better.

 

Let's assume that ALL the variables above are correct ( tires, allignment, rotation direction, pressures, etc... ) -

Will the addition of the Ricambi part 236786 : 1.5" spoiler to the front will have a noticeable improvement on my 348 Spider's road handling ? Not trying to sound ignorant but it does not "look" like it would change the air flow that much even at high speeds - since it is set back from the rounded factory bumper the air is already being directed in a similar matter. If it was 3" wide I could recognize an impact as it deflected more air... assumng this air deflection helps ground the car.

Why did the SS model have a forward protruding lip added ? I doubt it was for just looks. Does the SS lip design deflect more air to the sides ? Is that what this under mount lip is trying to mirror ?

I am sure someone smarter than me can tell me how all this works


As I said before, I have been very stable in the 130's but just knowing I can maintain that stability well above intrigues me.

 

as far as I am aware the chin spoiler should have been standard fitment to your Spider, it's not an aftermarket extra. The spoiler was part of the 'improvements' made to improve the car's stability at speed.

I can say from practical experience that at speeds of 120-150 mph along the Mulsanne straight at Le Mans the stability was good, particularly when you think this section of track is normally in use on a day to day basis by heavy trucks and is quite bumpy in places.
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These discussions always move off the fix to discussions of alignment, tire size, etc. That's squirrelliness, not floatiness. Excuse the technical terms.
The reason for floatiness (technical term-"floaticus asshopuckerus at speedicus") is too much air under the front of the car. The need is to move more air over and around the car and less under it. The splitter or lip on the bottom of the bumper causes more air to move over and around the car instead of under it. Floatiness fixed. End of story.

 

HAHAHA!

Right out of the ACME technical dictionary.

 

yeah-I had to google it!

 

Haaaaaaaahahaha!

You big idiot!!!

 

Well I always hear big numbers but never see them myself. I think it is safe to say that I may have the most race miles on a 348 and I either have a broken speedo or I have never seen 130+mph. Anyway my splitter was 4.5" and my car is lower than any streetcar. My car was almost undriveable with my splitter until I cranked up the rear wing. So just be careful of how much splitter you add. If I kept my car any longer I would have had to buy a more sustancial rear wing and my rear wing was already wider than the car and above the roofline with about a 1 foot cord.

 

I guess it is safe to say in your country maybe you don't have up two miles of straight to get a bit of speed up with all that scrap iron on the back your race car.

No offense, but I know what I see on the speedo and what we have been clocked at. Lets just agree to disagree.

 

90 348 stock setup sucks.....
squirrely compared to my other cars.