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348 solid flywheel experiment

Discussion in 'Technical Q&A' started by fatbillybob, Jun 5, 2004.

  1. fatbillybob

    fatbillybob F1 World Champ
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    Aug 10, 2002
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    348 solid flywheel experiment. i talked about doing dual mass to solid conversions. Does anyone whant to hear about it?
     
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  3. ShanB

    ShanB Formula Junior

    Jul 9, 2003
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    Yes. Would love to know how this turned out.

    Well???....
     
  4. Ricambi America

    Ricambi America F1 World Champ
    Sponsor Owner

    Yes!! Start typing man ! :)


    -Daniel
     
  5. MarkCollins

    MarkCollins F1 Rookie
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    Jul 2, 2002
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    Yes very interested :)
     
  6. ernie

    ernie Two Time F1 World Champ
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    Well come on with it Billybob. You know I have my old flywheel waiting to do this.
     
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  8. snj5

    snj5 F1 World Champ

    Feb 22, 2003
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    Russ Turner
    I'm even wildly interested and I don't have a dual mass flywheel. Would love to hear.
     
  9. RAYMAN

    RAYMAN Formula Junior
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    Even though I don't know what your talkin about..Spill it brother
     
  10. ernie

    ernie Two Time F1 World Champ
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    Hey Mundo

    It is way cool. Billybob and I talked about doing this a while ago. He finally got down and did it. In a nuts shell, he took all the grease out of the flywheel an welded it together. Last weekend he when to the track to test it out. I haven't heard back from him yet. So I'm still waiting Billybob you fat bastard. Hahahaaa.
     
  11. fatbillybob

    fatbillybob F1 World Champ
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    Aug 10, 2002
    19,034
    socal
    O.K. guys,
    Here is the deal....First Ernie sorry I have been so busy I have not called like I promised. Problem: 348 flywheel systems suck. Ferrari redesigned them several times all dual mass dual plate to dual mass single plate. 355's use the same system in single plate. 360's may use this too I'm not sure. Key problem is the 348 input/clutch shaft seal leaks oil past the crappy oil rings and wets the grease in the Flywheel (FW) pack. This causes the grease to thin and dampening fail either the plastic parts inside rattle or the other parts of the pressure plate multiple clutch pates and intermediate plate rattle. Your car symptom is hard hot starts or slow starts with cranking (due to bad vibes to sensors), and or rattle on shut down, melted internal plastic parts from friction. To a lesser degree 355's have this problem because they seal better. I have never heard of this problem on a 360 and I am not sure but believe thsy have a similar system gearbox in rear clutch house rear to gearbox.

    Ferrari Solution is to repak the FW with a $45 can of grease to the tune of a $1500 in/out of the clutch pack. Even for us DIY'ER's this is not only a 2 hour pain in the A$$ but also, we hate getting ripped for $45 bucks. Personally, I have used the correct kluber grease, marine wheel bearing grease, and a really high temp AGI cert I forget which it is grease used in industry and they ALL work! So you don;t need to spend 45 bucks the best grease was the hig temp stuff...I'll find the name latter.

    You heard it first on FC the Billybob solution...drum roll please....you open the FW pack gut the internals, cutt off the spider looking thing, cut off the rockwell hardness 70 hub spokes using 8 colbalt lathe bits, weld the hub to the clutch pack backing plate, spin balance it and put it all back together. I used the existing spacers but they can be a rattle source and will mill out an aluminium spacer with the 6-8 holes in it to clamp everything together in version 2.

    Results: I drove the crap out of the new system at Willow Springs International raceway for two days. It did not break. It worked perfectly. My car did not blow up. I drove harder than anyone would drive on the street. 1) I dropped 5 lbs off the assembly! 2) I almost stalled the car on first off the line due to the lightness of the FW. After I learned the feel of the clutch I do not notice it anymore. No problems 3) I can feel the car rev and exit the turns with more go juice. 4) Even with a well packed FW the car would take a second to start upon cranking. 5) Now the car fires the instant the key is turned. no more bad vibes to sensors. 6) There is no zero nada zip rattle vibration extra noise once over 1200-1500 rpm. My idle is 800 and I notice some small rattle that presumably the dual mass isolates. Is that important who knows. 7) There is a small shut down rattle (like a 3 round burst on a machine gun but quiet) when I turn the key off. This is no worse than the sound of a worn FW pack and is of no consequence. 8) all of this works with stock parts and uses stock parts. I just took out stock parts and modified stock parts. Until you open the FW you can see no difference.

    As I see it there is only the remote possiblility that harmonics below 1200 rpm could be a problem. I gain less rotating mass. I gain faster exist in the corners due to faster acceleration. I NEVER have to grease that damn FW again!!!! This is the biggest gain. So now the shafts can leak all they want. Negatives are a shut down rattle and just a bit more mechanical noise around idle which could be eliminated by turning up the idle to 1000rpm.

    So there you have it. YMMV. If anyone wants me to help them do this let me know. I need to find some better tools for my lathe like a beefy a$$ tol holder and diamond bits= big bucks. You see the hub needs to be cut with a "well" in it so that you can make a nice weld fillet to the clutch back. This makes it impossible to break. It is actually pretty costly to do this with welding/balancing and breaking tools. If people are interested in version 2 which in my head is a better design let me know. We may be able to get the cost of parts down by milling several spacer rings in aluminium. Also, on version 2 I'm going to cut out some slots in the FW itself and maybe some other lightening. That means more balancing but I think I can get at least another pound off the FW assembly. Every pound means more useable acceleration but yet it will look so stock.
     
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  13. snj5

    snj5 F1 World Champ

    Feb 22, 2003
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    Russ Turner
    this is truly brilliant work.
    great job!
     
  14. k wright

    k wright Formula 3
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    Feb 4, 2004
    1,679
    North East TN
    Cool write-up. Photos would also be greatly appreciated. The photos that I've seen don't give me a full picture on how this works, but from these photos it looks like the inner mass serves only as a dampener and does not transmit any torque. If this is the case could it not be competely removed? Is there any aftermarket company that makes a one piece flywheel for these cars? Lastly, if the 360 hasn't had this problem....what is the part number for the new and improved seal that we need to stick in our 348's and 355's?

    Thanks for your work.
     
  15. ernie

    ernie Two Time F1 World Champ
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    Right on Billybob!!!

    I kinda figured you have been busy, so no worries. I was just messing with you anyway. Okay dude my flywheel is gonna be the second version. I have the majority of next week off so I'll give you a call to set up a time when I can go down to your place. I'm thinkin wednesday night or thursday. I'll try to give you a call tomorrow. It was great to hear you picked up some exit speed out of the corners. Now your just gonna have to see how it does against your arch enemy, the M3. LOL. But this time you have to take out the windows. You will drop 75 pounds easy. That should make you even quicker, but you may have to get it corner balanced again.
     
  16. fatbillybob

    fatbillybob F1 World Champ
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    Aug 10, 2002
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    Well I don't know of a 360 part that will fit the 348. The 360 may be a totally different design. As to dampener yes that is all it does. The spider thing inside the FW does stop on studs so there is torque transmision after you slip the clutch. That is another thing you notice a faster lock-up of the clutch. this of course transmits more force down the line but can be no worst than a clutch dump with high revs which the car can take anyway. The duallmass absorbs some of that shock and sometimes on a dry but functioning FW you can hear the springs kind of coil and bind up when you let out the clutch. That is another subtle clue that your FW grease pak is going south but very few people can hear it.
     
  17. fatbillybob

    fatbillybob F1 World Champ
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    Aug 10, 2002
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    Sorry Ernie I'll be on a fishing trip for the next two weeks. First thing I have to do is find the right tool to cut tool steel hardness of the hub. Then we are in business. I think you will like it. As to M3's I have gotten past 3 in the last 3 weeks. They must have been on street tires. Perhaps they are bad drivers but before I could not even get close. However, one M3 absolutely smoked me last week. He was on shaved race radials and must have been 5 seconds faster than me around the track at least! The M3 has a quicker shifting SMG trans, about 40 more hp and better handling. I may have to go turbo and go gunning for Z06's!
     
  18. RAYMAN

    RAYMAN Formula Junior
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    Billy Bob, for me, you might as well have written that in Italian...Not a clue..LOL. Guess I have alot to learn.
     
  19. vincent355

    vincent355 F1 Veteran
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    Billybob,

    Awesome man!!!!

    Glad to hear you finally did it and it came together.
     
  20. ShanB

    ShanB Formula Junior

    Jul 9, 2003
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    Well done Billybob. Thanks for the explanation. Do you remember what grease you substituted for the magic Kluber-snot?

    Shan
     
  21. ricrain

    ricrain Karting

    Nov 1, 2003
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    I don't like that mess of a flywheel either (I've done mine recently), but I have to wonder if the whole point is having the dual mass act as the harmonic balancer.

    Since the 308/328's had rubber dampers in the front of the crank, they got their balance that way. But the 348 has a solid front pulley. If you go solid on both ends, don't you think increased harmonics (2nd order) could result in odd or premature main bearing wear?
     
  22. fatbillybob

    fatbillybob F1 World Champ
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    Aug 10, 2002
    19,034
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    Ric,

    I do not know but I do not think so. HB's are not balancers but torsional vibration dampners. TVD's are used primarily on the front snout because this is the highest concentration of harmonic issues. TVD is needed regardless of engine balance. However, I think that the 180 degree flat crank has differnet harmonic charactor than the typical SB chevy v-8. TVD can be solid ala 348 or solid ring/rubber/inertial ring. I don't know the ferrari engineers's design protocal or compromises. But my guess is that the front snout solid pully is the 348 TVD. Dual mass flywheels were never about being crank shaft TVD's but TVD's for the gearbox to prevent gb rattle of the gears at idle. This was first done I believe in diesel trucks. As GB parts got lighter and oils thinner we get more rattle. My 348 is acting true to form in that the slight rattle that I do have with my solid experiment is at idle and most rattle is on shut down. It is either all the twin disc parts rattling and or the actual gears rattling on each other. In my case the sethescope tells me it is the clutchshaft to pinion transfer gearset. This is in the same area as the bad design that caused at least 3 other 348 GBS to be rebuilt because of noise that is first diagnosed as a throwout bearing going south. GB gears are not subject to the same cracking vibration harmonic isuses as a crankshaft. A SB chevy and actually yield .030" on either end when run without a TVD! Now that kills cranks and main bearings. Also, TVD's are tuned to the predicted engine harmonics. You can't move and squeeze the TVD in your hand. But you can squeeze and move the DMF parts in your hand. They are for a different kind of vibrations. Finally the 348 crank ends at a floating input shaft. The most solid connection of the DMF is to the GB clutch shaft. IMO the DMF is truely for the GB and not for the engine so I do not think you can do any engine destruction. GB gears slap all the time and the small amount of slapping at idle I don't think is of any consequence other than to freak out owners. Finally, I got to see the engine guts of the one 348 imsa racecar with dinky 7" multidisc clutch and solid hub assembly. The crank on the car is stock 348 with perhaps more precise balance but stock nonetheless. To my knowledge there is no issue with this car blowing apart. In fact for those of you going to Monterey '04 for the FCA meet it will be on the track. It is all being redone as we speak by Scuderia Rampante bolulder ,co. Dave Helms is the man putting it together. He is has an awesome shop. My experiment continues... I am thinking about for version 2 a way to drill out the center of a TVD of a small light motor and weld it to the internal hub of the now gutless DMF. Solid ring/rubber/inertial ring style is more difficult to guess the outcome. A fluidamper style may be the hot ticket as the fluid responds over a wider range of vibrational input. The best solution may be to see what was changed in 355's and 360's. 348C guys use to run with the GB oil at minimum to reduce splash and oil down both these shafts. Maybe a small motormount change to tip the nose of the engine a few degrees would also minimize oil running down the shafts? Similarly you could grind out the rubber bushing at the trans mount and lathecut out a delrinoffset bushing and tilt the butt of the GB up a couple degrees. What do you think about that? Maybe repeat DMF grease wetters have a weak GB bushing and we all should be changing that rubber POS? YMMV!
     
  23. mad dog

    mad dog Formula Junior

    Jan 5, 2006
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    Solid flywheel experiment was a while ago now FBB. Any updates on how it has gone, or just nothing new to report?
     
  24. fatbillybob

    fatbillybob F1 World Champ
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    Aug 10, 2002
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    Well Since I built it I raced it up until 2008 when the car was destroyed by a Pbug. The clutch worked fine and my modification held up fine. It is in another's hands now but I assume it still has many many miles in it.
     
  25. UConn Husky

    UConn Husky F1 Rookie
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    Great work and write up! Now bring on the pics!
     
  26. 350HPMondial

    350HPMondial F1 Rookie

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    Rat F&*(#) Pbug,,, FU@$-Tard,,, dirty rotten no good P-hoser.


    It "Was" work of art,
    ,
    ,
    ,
    ,
    ,
    ,untill you hit it with your horse faced VW.

    ,
    ,
    ,
    ,
    ,,
    ,
    ,Bump my A$$ again,, I'll ##@$%&*@@# U up.!
    (Whew)

    Tell us how you really feel Fat Billy Bob....?

    Edwardo
    sorry about your Ferrari 348... (sniff)
    :(
     
  27. 350HPMondial

    350HPMondial F1 Rookie

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    #24 350HPMondial, Jul 8, 2008
    Last edited by a moderator: Sep 7, 2017
  28. ferrarilou

    ferrarilou Formula Junior

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    Sorry to hear your car is gone, particularly with all the good work you did on that car.



    Lou
     

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