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3X8/Mondial custom drop gears

Discussion in 'Technical Q&A' started by snj5, Feb 5, 2004.

  1. snj5

    snj5 F1 World Champ

    Feb 22, 2003
    10,213
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    Russ Turner
    Have been looking for replacement drop gears (the three gears removed during a clutch change) to give the Mondial a bit less buzzy cruise (current 60 mph @3000) and longer legs. The current ratios are a bit compromised between track and street.
    Drop gears to modify to both higher and lower final ratios are available. Tate at Carobu (www.carobu.com) offers sets done by our old friend, Frank Capo in Oz. They are straight cut gears, so they do whine a little, and DO require a different cover that comes with.
    Told him my requirement was to go from the current approx 20 mph/1000 to 22 - 23 mph/1000 rpm (23mph/1K: 60 mph = 2600 rpm, 70 mph = 3000rpm and 7000rpm = 161 mph)

    Of course, this will not correct the factory speedo error. My ratio change will probably decrease 0-60 times if you are into that, but your upper interval times will be about the same. For me the Mondial is way undergeared, especially with the new power. The magic of this is that 3rd and 4th become more effective 'working gears' on the street. Would not recommend this for the track. Tate will be getting the price back to me soon. May do this if $ not too bad at clutch change since the gears come out anyway.
    Also can get a lower racing ratio made if you are into that.

    No affiliation, yada. Just in case enquiring minds want to know.
     
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  3. mk e

    mk e F1 World Champ

    Oct 31, 2003
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    Dude, you're out of control :)

    Somebody, I can't remember who, is running them...Paul Sloan??....Anyway, I recall reading that it's most than a little gear noise, something about sounding like a blower under the hood. That said, my 1st gear (and second really) are useless with the increased power so I've been thinking about the same thing. I'd be interested in knowing the price.
     
  4. vincent355

    vincent355 F1 Veteran
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    Apr 8, 2003
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    Question:

    what do you guys mean by increased power? have you made som mods?

    Vincent.
     
  5. mk e

    mk e F1 World Champ

    Oct 31, 2003
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    Vincent,
    Russ has done a carb conversion and is fitting cams and custom exhaust and is closing in on 300 hp. My car is supercharged and up around 600. If you do a search by our user name you should turn up the threads about building both cars.
     
  6. Verell

    Verell F1 Veteran
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    May 5, 2001
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    Mk e,
    Have I overlooked a post w/some dyno numbers obtained after you sorted out your spark plug/ignition problems?
     
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  8. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
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    Almost all cars with a manual transmission, such as my old Honda Civic and my Toyota Celica, have straight cut reverse gears in the transmission. This is why so many cars make a particular whine when backing up, but don't do it going forwards. Straight cut gears are extremely noisy, but cheaper to make than diagonally cut gears, so many car manufacturers save a little $$ but making the reverse gears straight cut (most people don't care because how often do you back up for more than a few yards?). I can't imagine having straight cut forward gears in the transfer case. I would think it would be INCREDIBLY noisy. If the Mondial is your nice "cruising with the top down" car, I would not suggest putting in a set of straight cut transfer gears. Just my $.02.

    Birdman
     
  9. snj5

    snj5 F1 World Champ

    Feb 22, 2003
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    Birdman
    Good point about the reverse possibly giving the same whine. While I had initially imagined the engine sound would cover up the whine, my memories of reverse whine would be annoying. I need to find someone who has done this for a pirep.
    many thanks
    rt
     
  10. Ken

    Ken F1 World Champ

    Oct 19, 2001
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    Straight cut gears in a gearbox require a higher degree of skill to shift correctly, and yes they whine. I don't know if the drop gears would affect shifting ease but it's a question to ask.

    Ken
     
  11. 4re gt4

    4re gt4 Formula 3

    Apr 23, 2002
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    Ken: The drop gears are in constant mesh. They have nothing to do with shifting.

    Also, note that straight cut gears inside the tranny itself have no effect on shifting if the box is a syncromesh.

    Straight cut transmission gears? Bring on the earplugs.
     
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  13. mk e

    mk e F1 World Champ

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    No, I'm still working with calculated numbers until spring comes and I can get out to the dyno. I have the dyno numbers with the first blower 304rwhp or about 352 crankhp, and I corrected for the new manifold conditions (temp & pressure) and I get 620. I also calculated that it should take 450-500 ft-lb torque to spin the tires in second gear just rolling on the throttle, so it works out about the same. I'm dying to get to the dyno though, I'll post it when I do.
     
  14. pma1010

    pma1010 F1 Rookie

    Jul 21, 2002
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    Russ, from memory, QV London has also done this and can provide you with experience/parts/

    BTW, have you seen the posts on the Ferrari Classic racing series in the UK (328s/308s/Daytonas/246s all having a go)? QV cars finished first and second. Mondials were also run to good effect.

    Without (I hope) diverting this further, I have the 44s stripped and going into the carb dip. Will stick with 36mm venturis at start. Chassis with the QV recommended "race" alignment, modified forks (for camber), new springs and uprated ARBs almost done. Roll on track season!
    Philip
     
  15. snj5

    snj5 F1 World Champ

    Feb 22, 2003
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    Philip
    Thanks for the note. I went and drove it out to FoW and back today and will probably leave the gears the way they are for the time being if only straight cuts are available - The car is pretty loud already with the tubi and you had mentioned that changing the cam may make it louder.

    Can't wait to hear how your carbs turn out.
    Will keep the 36mm venturi in awaiting the hot cams, but if I were keeping the stock I might consider going back to 34mm chokes just as a fine tuning point for low end smoothness. It definitely runs better in the high rpm bands.

    On a side note -it's amazing to see how American Ferrari dealerships have changed. They used to be understated meccas for true hard core car guys, now it seems they are all glitz. Today was the first time I have ever been greeted by a 'Do not touch, sit on our cars..they are works of art' sign posted on the front door of a Ferrari dealership. Oh well. They were OK, just not as warm and down homey as FAF was in the 70s.... the new FoA (former FAF) is now glitzy as well. Different target clientele I guess. Well, enough pining for the old days - at least Grand Touring in Laurel is still all enthusiasts..
     
  16. thecarreaper

    thecarreaper F1 World Champ
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    Sep 30, 2003
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    straight cut gears suck on the street. if you want to torture yourself find a muscle car with the muncie rock crusher 4 speed and take it for a drive on the freeway/interstate. when your ears stop bleeding let me know. over 70mph sustained in my elderly Z28 will give you a headache. but its lots of fun for short blasts. with all the mods your f cars have , there must be another way to accomplish your goal.
     
  17. Birdman

    Birdman F1 Veteran

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  18. mk e

    mk e F1 World Champ

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    Very interesting, it says he has several ratios too.
     
  19. davehelms

    davehelms F1 Rookie

    Jan 3, 2004
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    Glen Sipe at Gear and Machine Specialitys in Atlanta I think. Glen has made me gears for many Ferrari's. Helical and straight cut gears, he does them all. Every 250 series car we ran on the track had Glens gears in the rear end as well.
    Dave
     
  20. snj5

    snj5 F1 World Champ

    Feb 22, 2003
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    This is great -
    will follow up
    many thanks
    Russ
     
  21. snj5

    snj5 F1 World Champ

    Feb 22, 2003
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    Dave - do you have a contact # or email address
    Many thanks
    Russ?
     
  22. atlantaman

    atlantaman Formula 3

    Mar 31, 2002
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    Glen made a xfer 308 gear for me years ago--he is--or was then--in Memphis--I have not heard from him in 10 yrs
     
  23. davehelms

    davehelms F1 Rookie

    Jan 3, 2004
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    Your right, it was Memphis. I will look his number up tomorrow. I speak with Glen a couple of times a year, and it was just about 4 months ago we spoke last. No one knows gears like Glen. Last set he made for me was for a T35 Bugatti and they were perfect
    Dave
     
  24. mk e

    mk e F1 World Champ

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    I wonder what you would do with just 2 gears, they would never mess with the third.....
     
  25. AR!

    AR! Formula Junior

    Apr 8, 2004
    974
    Berlin, Germany
    I have the same feeling about the gear ratio in my Mondial t, so I am really curious to learn about the result of your project!
     
  26. snj5

    snj5 F1 World Champ

    Feb 22, 2003
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    Talked to Glen Sipe - great guy.
    He said the way to do this was a new custom ring and pinion gear and that it would run about $4 - 6 K.
    A bit too much even for me, when you consider installation, whoch I think would entail dropping the transmission out.
    The idea of a quick easy drop gear fix seemed appealing - I think I will venture back into the black magic of Frank Capo in OZ and see if he has anything other than straight cut drop gears. Another option might be Ferrari UK to see if other ratios are available in their inventory.
    best
    rt
     
  27. AR!

    AR! Formula Junior

    Apr 8, 2004
    974
    Berlin, Germany
    Just saw at the Koenig website that they offer longer transmissions for the 348 for 3k EUR (installation additional 1k EUR).

    http://www.koenig-specials.com/

    Still quite a lot of cash considering that they basically only change three cogs ... ?
     

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