News

Would you degree wheel a 308 qv?

Discussion in 'Technical Q&A' started by tf308, Apr 21, 2004.

  1. tf308

    tf308 Formula 3
    Silver Subscribed

    Dec 14, 2003
    1,122
    Virginia Beach
    Full Name:
    Tim
    I finally have all of my belts reinstalled on my 308qv. The motor is out of the car on a crate. Would you bother with a degree wheel? I have all of the marks aligned, ie. the PM14 mark is dead on and all the cams are dead on.

    I ask this because as I come up to pm14 on the flywheel the intake appears to open at 16 BTDC which is correct, but the PM58 looks more like 10btdc. But, this is just a fast visual not accurate with a dial indicator ( I dont have one)

    what would any of you do? Would ferrari techs say that this would be ok as long as the marks all line up? Opinions greatly appreciated.
     
  2. mk e

    mk e F1 World Champ

    Oct 31, 2003
    11,505
    The twilight zone
    Full Name:
    The Butcher
    I got it in my head that the because of the width of the grooves the only right way to do the cams was with a degree wheel....I had a couple question and called a couple ferrari dealers, but no one at the dealerships had ever done cams with a degree wheel.....but I continued and found out that as long as the marks were lined up, the cams were in spec. I just use the marks now.
     
  3. chrismorse

    chrismorse Formula 3

    Feb 16, 2004
    2,149
    way north california
    Full Name:
    chris morse
    I've only had the car a month and a half, but I love engines and this car in particular. If no one else comes up with a better suggestion, I would opt for certainty. Buy the degree wheel and the dial indicator and get it to the point where you feel good about it - that it is right. Next time you do the job, you will know what one tooth or 10 degrees or a half notch means.
    Go for certainty, this could be a bit of performance lost, not likely bent valves???
    Experience is worth a great deal more than hot air, (which is all I have to offer).

    good luck,
    chris
     
  4. mk e

    mk e F1 World Champ

    Oct 31, 2003
    11,505
    The twilight zone
    Full Name:
    The Butcher
    I should add that the way ferrari specs the timing, you need to shim the valves to 0 clearance before taking any degree measurements or everything comes out wrong. If you search the old archieves you should find directions.
     
  5. davehelms

    davehelms F1 Rookie

    Jan 3, 2004
    4,629
    Full Name:
    Dave Helms
    Use the flywheel as your degree wheel. It is marked for the valve opening and closing points. Check it with a dial indicator on the 1 piston at TDC (PM1/4) and make sure that mark is accurate (usually within 1 degree) Readings and adjustment are done with the valves set to .5MM
     
  6. atlantaman

    atlantaman Formula 3

    Mar 31, 2002
    1,726
    Roswell, Georgia
    Full Name:
    Charles
    You should go back and check some older posts on this--on my old 308v4 motor I found the cam marks to be off about 4 degrees. I would not have known this if not for applying the degree wheel.
     
  7. Verell

    Verell F1 Veteran
    Consultant Owner

    May 5, 2001
    6,992
    Groton, MA
    Full Name:
    Verell Boaen
    If you're going for max performance, esp up near redline, say for a track car, then use every tool you've got (flywheel marks, dial indicator, special shims, & degree wheel). There are several excellent threads in the Old FChat archives.

    For spirited daily driving the cam/cam cap marks & flywheel PM1-4 mark are sufficient. They'll get you within factory tolerences.

    BTW, I've got scaleable artwork for making your own degree wheel. Just print it out & glue it to a sheet metal disc. If anyone is interested, go to:
    http://www.tavia.com/free_degree_wheel.html

    I found it on the web, Tavia is offering it as advertising. Of course some jmoke has started selling a copy on eBAY!

    Just wish I"d found it before I spent a hundred bucks for summit's degree wheel kit.
     

Share This Page