348 on a cheap diet

That's a Michelletto built "GT" Competizione. I don't think the factory Competizionne had built in head lights. They do look cool though. Probably not hard to replicate.

I like that CF steering wheel.

 

If it gets to slick from saliva you might have to add sticky tape which would add weight!! LOL

 

There are many great suggestions, and like you, have the car (lowly 308) on a diet. Color me clueless about what your car has and does not. So these are best guesses... lighter weight all aluminum radiator, aluminium lightweight adjustable shocks, raise your spring rate... A lightweight flywheel and clutch can help.

FYI: i run with Pilot Sport PS2 on the track and they are very good, but frankly the car here is now at the point to where i have more suspension than tire adhesion in the twisties. You might want to get another set of lightweight rims and mount Mich Pilot Cup or Hoosier dry day tires (use the PS2 for the wet track days).

Also, the brake rotors, go aluminum hat floating. See Fchat sponsor Girodisc Save as much unsprung weight as you can.

Wish i knew more, but your model is foreign to me in this regard, sorry

 

Actually there is some truth to that. The saltflat guys tape over the creases on the hood of the car, bumper, lights, etecetera. It's helps to reduce drag, and gives them a few more mph on the top end, which is what running on the flats is all about.

 

Removing rotating mass is more effective than removing static mass, and the faster it's rotating, the more effective - i.e. flywheel mass reduction is better than wheel weight reduction, which is better than frame weight reduction. Unsprung weight reduction also is very desirable - tires and wheels vary a lot, even for the same size.

If you remove body mass, make it high-mounted mass first, and also look at the front and rear ends.

Any weight savings is great, and our business, along with our more publicized cosmetic carbon fiber parts, is vehicle weight reduction through the use of lightweight composite body panels.

Other firms do a great job with lightweight flywheels, clutches, springs, lugs, wheels, tires, etc.

 

I don't see much benefit in the cf body panels. Because wich part would you change? The door airinlets when the stakes are removed are ultra thin gfk doesn't weight much would maybe safe 0,25kg made of cfk instead. The front fenders are metal could be made of cfk but they are also not that heavy. If its a street car i would go for thin gfk layers anyway because the weight difference between a gfk to cfk isn't that much. The Rearhood is also in stock very light. The aluminium fronthood would be ok made of gfk or cfk. Also the roof. If you change to complete gfk or cfk doors it would be much lighter but i wouldn't drive that without an cage wich adds more weight then safed. As a result on the outer body i wouldn't do more then change both bumpers to 355 challange bumpers. Rearwindows and Sidewindoes out of makrolon or lexan. Doorstakes removed. And maybe a gfk or cfk fronthood. And removed electricmotor in the side mirrors. Mine weights 1100kg dry that should be ok for the street with some rest comfort. F.e. Makrolon Sidewindows are scratched very fast and you can change them every couple of month, i won't handle with that on my street/all day car.
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Samy

 

Samy, I agree with your analysis to a large degree. We've done the hood and front fenders in carbon fiber - these are about 1/3 the weight of stock in both cases. Door scoops are heavy - 11 lb. each side. Bare door shells are about 30 each if memory serves me right - but carbon doors, at least as we've had experience with them so far, would indeed require a roll cage for safety.

Little things like foot rests, brackets, and stuff really add up - they're ususally steel and non load-bearing.

In my experience, the 348 seems to be built with only the most cursory regards to weight savings. I'd say most of the parts (non-drivetrain) I've seen are comically heavy. Not a great deal has changed, by the way.

You'd see an appreciable weight savings if you replaced a lot of stuff at once as opposed to just a panel or two. Great way to rebuild a wreck, though.

Our body panels are still in development to a degree, but the front fenders are pretty much ready to go - they're carbon fiber/Kevlar/epoxy - autoclave cured.

Pics and prices later.

I'm not going to push this stuff too hard on this particular thread, as the title was "Cheap Diet."

For $20 - $30 grand or so, a 348/355 could be made ridiculously light.

Chris

 

Did you have the exact weight of a stock fender and the weight of a cfk fender?

The footrest was the first part i throw out. Such an heavy useless part. Why they dont use lighter and cheaper plastik for it Or the metal doorhandels/openers for such an small part realy heavy.

I removed the stakes in the doorscoops and that made the part realy light 80-90% of the doorscoopweight are the stakes.
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Samy

 

From memory, 355 stock front fenders are 9-10 lb each. I'll have to re-weigh them to be absolutely sure. I do not know for sure if they are the same material as the 348 fenders - the hoods I know are both aluminum. Our CF/Kevlar fenders are 3 lb.

Smart move on the foot rest.

It is funny how heavy the door handles are - like fishing weights.

I see what you mean about the strakes - once these were removed, there wouldn't be a lot of mass left in the scoop.

 

Put 100kg in and then take it out and you will see. But the suspension is adjustable so you can just lower it after the cars diet.
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Samy

 

I saw Marcel's copyrighted photo of Jim G's 0846 and noticed that it had inboard rear brakes early in its race life.

Inboard brakes lower your unsprung weight; a good thing. Pic included below.

Also, other vehicles such as the Hummer H1/HMMWV use inboard brakes, as does the Suburu G series (which uses front inboard half-shaft drum brakes to further eliminate rotors entirely).

The Jaguar E-Type also used inboard brakes.

Another way to lower the 348's weight would be to dual-use one of the engine radiators for the heater core duties so that you could remove the dedicated front heater core.
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Loose weight and drive naked..

 

I was surprised at the weight of the package from the Tire Rack when my new rear brake rotors were delivered. The rotors (naked) weigh nearly 16 pounds each.

 

Glad to hear you got your rotors! They are a set of pigs...the Brembo setup is 11 lbs per rotor if I remember right without looking at my setup.

 

You could move the rotors inside the engine compartment, directly on the half-shafts. You could even make wider calipers, turn them 90 degrees, and use the half-shafts as your brake rotors.

Or you could go to rear drum brakes on your half-shafts.

Any of the above would lower your unsprung weight. In board brakes have been on several successful race cars.

 

I wish Girodisc (the sponsor here) would make some of their upgraded rotors for the 348 instead of just 360 etc. The weight comes from the hat being massive on the stock cast compared to the aluminium hats on the 360's etc. Only alternative I have seen is it basically go Brembo or Stop Tech....and I have searched a lot.

 

I weighed my stock 348 wheels: Front with newer Bridgestone S01 = 53.5 lbs. , Rear with older RE71 Bridgestone 59 lbs. That's with bathroom scale.

I am going to take the challenge wheels off this weekend just to weigh them.

 

That just seems backward. Maybe it's just me.

 

Cool.