Removing air pump drive extension from exhaust cam | FerrariChat

Removing air pump drive extension from exhaust cam

Discussion in '308/328' started by dave80gtsi, Dec 12, 2007.

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  1. dave80gtsi

    dave80gtsi Formula 3
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    Dave Meredith
    #1 dave80gtsi, Dec 12, 2007
    Since my 308 no longer uses an air pump (removed for off-road use only, mind you ... cough cough) I am left with the now-beltless air pump drive wheel sitting on the end of the rearward exhaust cam.

    Removal of the now-useless wheel shows that it is mounted to the end of the exhaust cam, held in place with one of those funky shaped jam nuts, with no obvious way to remove the 'extension" from the cam end.

    So, I now have this "stud" sticking out of the end of the rear exhaust cam, spinning out in space as the engine runs.

    Anyone know how to eliminate this extension, in the name of a cleaner engine compartment?

    Two (2) possible ideas come immediately to mind:

    a) locate a spare exhaust cam for the front bank of the engine w/o the air pump drive, and do a cam swap, or:
    b) remove the cam, and cut off the useless protruding bit. I'm betting that this might be easier said than done, as I can imagine that the cam is made of some pretty hard steel that might not cut easily.

    Anyone B.T.D.T.?

    Thnaks and Cheers - DM
     
  2. 2NA

    2NA F1 World Champ
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    Tim Keseluk
    #2 2NA, Dec 12, 2007
    Harder than a woodpeckers lips.

    Leave it alone.

    Look forward to the day when all that emissions garbage will bring more money at resale.
     
  3. Artvonne

    Artvonne F1 Veteran

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    #3 Artvonne, Dec 12, 2007
    You cant swap exhaust cams front to rear, they have different spacing on the cam bearing journals, plus the drive pulley end is part of the cam, so you would have to cut it off and plug the end of the cam to hold oil pressure, and block off the hole in the back of the head to do what your contemplating. Your only other option is to find a different cam, but probably a set of cams, from a car that didnt use an air pump.

    Kermit, who used to post on this board, did flow bench work and modified several 2V injected cars. He claimed the early carb cams would work in the 2V injected cars with some playing around, but thats maybe more than you wanted to do. The injected cams arent worth much, so nipping the end off that cam wouldnt be a real big deal. Call around, you can probably get another injected cam pretty cheap to keep as a spare in case you sell the car someday.
     
  4. pad

    pad Formula 3

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    #4 pad, Dec 12, 2007
    I know that on certain years, the air pump extension is pinned to the end of the cam. You need to take the cam cover off, remove the end cap, and use a "special" tool to remove the pin. Then, as previously stated, you must plug up the end of the cam. On my '83 QV, I had to cut off the end - there was no pin.
     
  5. Artvonne

    Artvonne F1 Veteran

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    #5 Artvonne, Dec 12, 2007
    My 77 isnt pinned either, its all one solid piece. But I thought I recalled seeing one pinned. Being a Ferrari you just wont ever know until you look, lol.
     
  6. Yamaric

    Yamaric Karting

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    Richard Dalgleish
    #6 Yamaric, Dec 13, 2007
    My 80 GTSi isn't pinned either, I think only the intakes are pinned for the distributor drives.
     
  7. dave80gtsi

    dave80gtsi Formula 3
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    #7 dave80gtsi, Dec 13, 2007
    Really? That's very curious. Not doubting your word, but why go to the effort of making a unique cam for each bank of a V-8?

    Looks like there's no removable "pinned" part to my existing exhaust cam, so removing the offending piece isn't an option to me - thus the original question.
     
  8. BigTex

    BigTex Seven Time F1 World Champ
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    Bubba
    #8 BigTex, Dec 13, 2007
    Put the nut back on it..........it won't hurt anything......

    When Mechanics ask me, I tell them it was for the Italian Expresso Grinder power take off, and I didn't elect to buy that option........;)
     
  9. Brian Harper

    Brian Harper F1 Rookie
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    #9 Brian Harper, Dec 13, 2007
    The two timing belts run on the same plane, driven from two side by side pulleys right above the crank's harmonic balancer. Thus the front bank's cams need to reach just a little but farther out to the belt. I think this was done to make the engine a little bit shorter so it would fit across the car even though it was a bit more expensive.
     
  10. WaltP

    WaltP Formula 3

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    #10 WaltP, Dec 13, 2007
    I removed the pulley on mine and replaced it with a grinding wheel. Now I sharpen my Wife's knives with a Ferrari knife sharpner.
     

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