400 GTA - Top speed and maintenance suggestions | FerrariChat
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400 GTA - Top speed and maintenance suggestions

Discussion in '365 GT4 2+2/400/412' started by Flo400, Sep 5, 2011.

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  1. Flo400

    Flo400 Formula Junior

    Jun 8, 2011
    358
    Munich, Germany
    Full Name:
    Florian
    #1 Flo400, Sep 5, 2011
    This weekend I drove on the German highway and tried to test top speed. The fastest I could go was at 5.500 rpm a speed of 225 kmh (or 140 mph). Now that's the speedo, considering it was being a bit optimistic that was probably more like 215 kmh (135 mph) but not less. I am wondering how much faster the car should be going - I couldn't go beyond 5.500 rpm and the way up to 6.500 rpm should provide a lot more speed.

    It is an automatic transmission - that can probably cost some top speed, but I have no idea about what top speed should be considering her age.

    I plan to have a maintenance the next few weeks, so I am looking for suggestions what should/could be done without doing dangerous or extremely expensive stuff. I came up with (hope that my english is correct):

    Changing air filters (mine are quite old)
    Change gas filters
    Synchronise carburetors
    New spark plugs
    Check valves and belt
    (Fluids were changed beginning of this year)

    The past 2 years I have used the car often as a daily driver so lots of really short trips - the car couldn't go beyond 4.800 after that... Only recently I have completed 1.000 km on longer trips, the engine now runs well, burns no oil. I recently passsed 100.000 km (62.000 miles) and I have maintenance records for every 5.000 km service from the beginning.

    I hope that doing the above work will make the car run even smoother and maybe make her a little faster. Any more suggestions/thoughts?
     
  2. wrxmike

    wrxmike Moderator
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    Mar 20, 2004
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    Mike
    #2 wrxmike, Sep 5, 2011
    Check & set the ignition timing, and consider replacing the distributor caps and rotors.
    Also, I think you probably mean "chain" when you say "belt", the camshaft's are driven by a chain in that car. It does stretch, and with 100 000k's on the clock, it's hopefully been replaced at some point in the past.

    M
     
  3. Ashman

    Ashman Three Time F1 World Champ
    Owner Silver Subscribed

    Sep 5, 2002
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    John
    #3 Ashman, Sep 5, 2011
    Last edited: Sep 5, 2011
    New air filters and spark plugs will probably help a little, as would checking the timing and making sure that the carburetors are tuned properly.

    The advertised top speed of the 400 GTA is right around 150 mph, if I recall correctlly. Given that Ferrari has in the past sometimes published optimistic data about its road cars, you may not be too far away from the real top speed attainable in these cars.

    I don't have the formula or the data about the transmission and rear end ratios handy but you can eliminate any uncertainty about the true top speed of the car caused by the speedometer by calculating it from engine revs. Depending on gear ratios, many cars are not able to reach redline in top gear, so only reaching 5,500 rpm may not be a fault of the car. I don't know if that is the case with the 400As.
     
  4. wrxmike

    wrxmike Moderator
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    Mar 20, 2004
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    #4 wrxmike, Sep 5, 2011
    Or use a GPS :).

    M
     
  5. Flo400

    Flo400 Formula Junior

    Jun 8, 2011
    358
    Munich, Germany
    Full Name:
    Florian
    #5 Flo400, Sep 5, 2011
    Thanks! Yep, I suppose that since I have the old stamps for every 5k kms maintenance the chain has been replaced more than once. I know the workshop where it has been replaced 5.000 kms ago but I will have it checked if its still tight. I'll ask my current workshop about the distributor caps and rotors as well...
     
  6. Flinch

    Flinch Formula Junior

    Nov 15, 2009
    302
    Holland and Sweden
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    Peter El Cheapo
    #6 Flinch, Sep 6, 2011
    The best maintenance is to drive it! From my experience I can only say the the sparkplugwires and ingnition will need some attention anually. Getting to the distributors and contact points (is that correct english?) can be a hassle though.

    As for the top speed : I do not know. My GTa cruizes perfectly at 100mph, but I never went over 130 (loads of power left). Just too much police hassle if I get cought.
     
  7. SouthJersey400i

    SouthJersey400i Formula 3

    Mar 14, 2007
    1,679
    Romulus, NY (Finger Lakes)
    Full Name:
    Ken Battle
    #7 SouthJersey400i, Sep 6, 2011
    Flo
    Checking valves, especially exhaust, is not a trivial matter on this motor. Cleaning carb jets might be useful, but as stated best way to do that is driving it hard!
    Ken
     
  8. billg

    billg Formula Junior

    Jun 7, 2006
    307
    New Orleans
    Full Name:
    Bill Grady
    #8 billg, Sep 6, 2011
    You're about at the top. I had mine right where yours is, and that was it. If this disappoints you, trust me when I say the GTA is by far the best of these.
     
  9. Fritz Ficke

    Fritz Ficke Formula 3
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    Jan 3, 2006
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    Fritz Ficke
    #9 Fritz Ficke, Sep 6, 2011
    I have GPS checked my 400I at 146 MPH before I ran out of track. I have a fresh engine and it would not do that when I brought it, the previous owner thought it ran great!
    The chains really stretch after 50,000 miles and retard cam timing and bounce will happen the short valve guides are shot by then to, My car was a bit of a slug till then engine out service. I believe most of these cars do not run really well, but good enough for Boulevard cruising and audio delight.
     
  10. hoverland

    hoverland Formula Junior

    Aug 14, 2010
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    Norway
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    Harald Ø
    #10 hoverland, Sep 6, 2011
    Lack of power above 5000rpm is likely to be ignition related, so making sure the coils have enough time to "charge" by keeping the dwellangle close to 40deg might do the trick.
    My 400A lacked power in the top rpms after setting contact breaker points to factory spec by blade gauge. This gave 31.5deg dwellangle and insufficient time for coils to build up the field -resulting in very little energy actually delivered to sparkplugs. (same symptoms as fuel starvation)
    After setting my dwellangles to 38.5deg it runs perfectly also in the high rpms.
    Also check resistance in sparkplugcable, total resistance should not exceed approx 5Kohms for the longest cables (cyl 1&12), preferrably they should be around 2Kohms.

    Harald
     
  11. It's Ross

    It's Ross Formula 3

    Jul 30, 2007
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    #11 It's Ross, Sep 12, 2011
    My FI '82 400i auto has seen an indicated 260kph, hovering right at redline. I doubt I was traveling 160MPH but it sure sounded great.
     
  12. laperriere

    laperriere Karting

    Mar 10, 2006
    162
    Montreal
    #12 laperriere, Sep 13, 2011
    Reached effortless 146 mph in Italy. I did not have the feeling it was the maximum speed.
     
  13. Flo400

    Flo400 Formula Junior

    Jun 8, 2011
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    Florian
    #13 Flo400, Sep 13, 2011
    Is that with a 400i or a carburetted version? I'd be happy with 146 mph... will follow all the suggestions on my spring maintenance.
     
  14. greyboxer

    greyboxer F1 World Champ

    Dec 8, 2004
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    #14 greyboxer, Sep 13, 2011
    Isn't there a maintenance schedule in the owners manual ?
     
  15. NickKerigan

    NickKerigan Karting

    Mar 17, 2011
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    Oxford, UK
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    Nick Kerigan
    #15 NickKerigan, Sep 13, 2011
    My 400i has been measured at over 150mph, but then it is a 5-speed.
    I think you should be able to get close to that in an auto.
     
  16. Ak Jim

    Ak Jim F1 Veteran
    Owner Rossa Subscribed

    Dec 23, 2007
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    North Pole AK
    #16 Ak Jim, Sep 13, 2011
    Do you rember what the RPM was at that speed? I've had mine up to 6500 in 5th.
     
  17. GreggG

    GreggG Karting

    Jul 14, 2008
    202
    New Jersey
    #17 GreggG, Sep 13, 2011
    Last edited: Sep 13, 2011
  18. laperriere

    laperriere Karting

    Mar 10, 2006
    162
    Montreal
    #18 laperriere, Sep 14, 2011
    400 IA, 1979. There was a Ford GT roaring behind the car, apparently requesting to free the left lane, which I did. The Ford passed the Ferrari and quickly disappeared! Olivier
     
  19. Flinch

    Flinch Formula Junior

    Nov 15, 2009
    302
    Holland and Sweden
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    Peter El Cheapo
    #19 Flinch, Sep 14, 2011
  20. Flo400

    Flo400 Formula Junior

    Jun 8, 2011
    358
    Munich, Germany
    Full Name:
    Florian
    #20 Flo400, Jun 2, 2012
    Just to finish my old thread with the results:

    Some of the wires and caps that connect to the sparks were replaced, there were some channels completely closed (dunno in english) that we opened up again with some needle device and carbs were cleaned (if that is the right term). Car was running only on 9 cylinders.

    Now we're back on track and on the dyno the car went all the way up to top rpm. Drove it today on the highway, guess it was around 146 mph and not quite at the end (biut not much more). That is scaling the 260 kmh down by the normal margin of optimism on the tachometer - the car drove 136 kmh on the dyno and it showed 150 kmh. Need to replace my old tires before I do more testing. Happy.
     

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