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512tr compression/leak down testing?

Discussion in 'Boxers/TR/M' started by gregklanderman, Feb 5, 2020.

  1. gregklanderman

    May 31, 2006
    10
    Boston/North Shore
    Full Name:
    Greg
    Hi guys, I am looking to join your fold and considering a PPI on a car. Can anyone tell me about how many hours it should take to do a compression/leak down properly for a PPI, and what acceptable values should be? It is a euro model if it makes a difference. I have searched but not found much detailed info.

    thank you,
    Greg
     
  2. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    A leak down is for diagnostics.... no value in a ppi... relatively high time consumption
    A compression test is for problem detection.... relatively low time.

    a comp test and thorough ppi will need no more than 2 hrs.

    Just an opinion.
     
  3. Rifledriver

    Rifledriver Two Time F1 World Champ

    Apr 29, 2004
    26,949
    Austin TX
    Full Name:
    Brian Crall
    #3 Rifledriver, Feb 5, 2020
    Last edited: Feb 5, 2020
    I disagree 100%.

    PPI in 2 hours? No wonder so many people are getting stuck with POS cars.

    Leak down test is a far better indicator of engine condition.

    A good motor can generate a bad compression test. A good leak down test cannot be generated by a worn motor.

    In any event depending on mileage I generally do not perform either on Ferrari 4 valve engines of the period unless dictated by symptoms.
     
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  4. MOSS

    MOSS Formula 3
    Rossa Subscribed Owner

    Apr 28, 2004
    1,255
    Totally agree! A leak down test as I have performed takes a lot of time (more than 2 hours) and it takes a very knowledgeable guy to do it right. Brian is that guy but if the engine is in tune and running great why go there? Save the expense and put the time in another area where its needed. Besides I have seen leak down tests show less than desirable results (usually because done wrong) and the car has great power and runs great. Then the worrying begins. 20 years later the car still runs fine and worry for nothing.
     
  5. Loulou_77

    Loulou_77 Rookie

    Jan 5, 2020
    1
    Full Name:
    Louis DUC
    The engine of the 512 TR has a compression ratio of 10.0:1.
    The rule of the thumb to translate it in bar is just to multiply the comrepssion by 1.2. So you should find a value close to 12 bar per cylender. The value should depend of the tools/ way the mesure is done. There is some tool where you do not screw it, bu just push it, so there could be a leak.
    One thing which is interesting in a compression ratio, is not the absolute value, but the dispersion of each cylender. The lower, the better.
     
  6. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    How does a good motor have a lone cylinder with inordinately low compression?
    How does a good motor have all cylinders showing excessively low, but consistent readings?

    Either one in my book rejects a car for purchase... no matter the story as to ‘why’. Move on... better, no stories cars are out there.

    More than 2hrs without checking compression?

    Drive - 25min
    Lift and inspect -40min
    Check all the buttons/ functions - 15min
    Hook up computer & scan - 20min
    Write up results - 20 minutes

    Yeah... I could see 3 hrs with a comp test... but not without. What am I missing?


     
  7. MOSS

    MOSS Formula 3
    Rossa Subscribed Owner

    Apr 28, 2004
    1,255
    Very rare to run across this issue.


    Sent from my iPhone using FerrariChat.com mobile app
     
  8. Rifledriver

    Rifledriver Two Time F1 World Champ

    Apr 29, 2004
    26,949
    Austin TX
    Full Name:
    Brian Crall
    Lots.
     
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  9. gregklanderman

    May 31, 2006
    10
    Boston/North Shore
    Full Name:
    Greg
    thanks for the replies all..

    Brian, can you be more specific as to why you generally would not do either as part of a PPI if the leak down is a good indicator of engine condition? Just if it runs well and has relatively low miles you don't expect it to show anything, and it takes a lot of time/$?

    I should have mentioned, the car has about 25k mi.

    thank you,
    Greg
     
  10. V4NG0

    V4NG0 Karting
    Silver Subscribed

    Dec 14, 2018
    141
    Full Name:
    Vinny
    When I had a PPI done on my car, the (factory) tech said he would be able to tell when driving it as part of the inspection if a test was necessary. Doing one absent any indication for actual need would likely be a waste of time and money, he said.
     
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  11. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    A leakdown test tells you WHY an engine has a compression problem.

    The question is:

    Buy it
    or
    Don’t Buy it

    who gives a rip WHY the engine has a compression problem.

    Answer:

    Don’t Buy It.
    Spend your research money on a different car.... UNLESS the car in question is stupidly cheap.

    Rifledriver:
    “Lots” may work on your customers with more money than brains.... but that dog don’t hunt. If you want credibility you need to provide supporting information.
     
  12. turbo-joe

    turbo-joe F1 Veteran

    Apr 6, 2008
    6,001
    southwest germany
    Full Name:
    romano schwabel
    if you would meassure the HC before the cats and it is below 200 ppm there is no need to do a leak down test
    but if the ppm are higher such a test is a must, even the higher HC may be a result of other things
     
  13. MOSS

    MOSS Formula 3
    Rossa Subscribed Owner

    Apr 28, 2004
    1,255
    My first question is what is your credibility? Not an attack just seeing what skill set you are at and how did you get it. Rifledriver does it for a living and very well respected shop.
     
  14. Rifledriver

    Rifledriver Two Time F1 World Champ

    Apr 29, 2004
    26,949
    Austin TX
    Full Name:
    Brian Crall
    To you? Why bother.
     
  15. Rifledriver

    Rifledriver Two Time F1 World Champ

    Apr 29, 2004
    26,949
    Austin TX
    Full Name:
    Brian Crall
    The 4 valve engines of that period were the toughest and most robust engines Ferrari ever made. When they did have issues it almost never manifests itself as a compression issue. For any given model there are known weak links so to most profitably spend your time and your clients money focus on those. I would never dream of doing a PPI on a 355 without a leak down test, but we know that is an area of potential trouble. When I hear hoof beats I don't spend a lot of time looking for Zebras.
     
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  16. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    My credibility...

    Lets’ see...
    Mechanical Engineer - California Polytechnic University - more than 30yrs experience. Built oil and gas facilities all over the world. Wrenching don’t pay bills.... wrenching is a BORING profession doing the same thing over and over again....

    As a kid... I worked for Electramotive under John Knepp back when Don Devendorf and John Morten were driving. MULTIPLE Manufacturers’ Championships. Both John and Don were brilliant people truly worthy of respect. I am honored to have worked with them. Electramotive guys put ALL of these F-car downstream techs to shame. Simply no comparison.

    I work on these F-cars as a hobby - not a vocation.

    But frankly.... what is ‘right’ is more important than the messenger. I can demonstrate my assertions and am happy to do so. If the data proves me wrong, I am eager to realign my understanding with the facts. As you know, I very frequently ask technical questions here on F-Chat and am most appreciative for the knowledge that is frequently shared. Let somebody explain WHY their PPI version is worth big bucks.... then lets discuss whether or not the ‘to-do’ list has merit.

    ****Lets talk FACTS and quit slinging BS.****

    If the car is worth only 100k - is is NOT worth spending 4 or more hrs ($600 plus) on evaluation. A ppi is for screening. With so many of these cars available it is STUPID to waste the money. If a ‘Professional’ can’t screen a 100k car in 3 hrs with a compression test... in my book, his credibility, expertise an/or honesty is to be questioned.

    A 6 million USD car is different. If you are charged that level of cost to evaluate a Testarossa you are are being played as STUPID by a thieving tech. Run Forest RUN!

    So many techs in this industry charge STUPID money and promote their mystique on the tail feathers of Ferrari. These cars are NOT mystical... nor are their independent techs. The knowledgeable people associated with Ferrari DESIGN, ENGINEER and CAMPAIGN the cars.

    There ARE good shops out there. Honest, open, experienced and quality... I always recommend Salerno. Ben would never charge excessively and justify it by saying “we did lots”. My only affiliation with them is as a retail customer.

    https://www.salernomotorsports.com/

    Shops like FoS have ZERO merit in my book.

    Here is a few pics...

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  17. gregklanderman

    May 31, 2006
    10
    Boston/North Shore
    Full Name:
    Greg
    Thank you Brian, that makes sense.
     
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  18. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    It makes “Lots” of sense.
     
  19. MOSS

    MOSS Formula 3
    Rossa Subscribed Owner

    Apr 28, 2004
    1,255
    I would dang sure rather have wrenching experience than book or theoretical experience. It does pay the bills for a lot of guys too.
     
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  20. Rifledriver

    Rifledriver Two Time F1 World Champ

    Apr 29, 2004
    26,949
    Austin TX
    Full Name:
    Brian Crall
    A lot of us have both. We just don't need to brag about it.
     
  21. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    They are complimentary skill sets.... not substitutes. Techs without engineers are worthless. - Engineers without techs are worthless.

    A wrench being swung by somebody with no understanding of torque or materials science is truly a dangerous thing.

    Keep in mind... learning by doing, requires MISTAKES. What did the tech learn while working on YOUR car? Let’s face it... without a proven record, one must hope that YOUR tech is intelligent enough to even learn from their mistakes.

    This is one area in which Rifledriver excels... he has factory training (unknown level) under his belt. I honestly asked to learn from his input... what does he do in his hr intensive ppi??? Unfortunately “Lots” is not an answer... it is avoidance....

    I have full respect for those who wrench.... IF they deserve it. To me, it is boring... BUT it can be an honorable profession. You and I both know how many crooks slither within the car repair industry. 30 plus years of providing the oversight over factory reps, engineers and techs has taught me to recognize BS.
     
  22. MOSS

    MOSS Formula 3
    Rossa Subscribed Owner

    Apr 28, 2004
    1,255
    And college degrees have zero relevance. Some of the best mechanics, techs and even engineers I have ever seen had a HS diploma.
    God given talents and training under a master of the art go way further.
     
  23. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    John Knepp was not an engineer... brilliant.
    Don Devendorf was an engineer... brilliant.
    Their respective skill sets complimented each other to win multiple championships. Fact.

    Honestly... Moss... I am really at a loss to hear you say that an engineering degree has “zero relevance”. We are on different planets.

    BTW - my “credibility” was specifically questioned and answered only upon request. A far cry from “bragging” as Brian asserts. In no way do I present myself as ‘expert’. I am here to learn from others. You both, for lack of qualifications and facts are choosing to instead make personal attacks.

    Let’s get back to factual discussion rather than BS.

    Still waiting to hear the content of Rifledriver’s ppi to justify his exorbitant costs.

    Still waiting...
     
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  24. MOSS

    MOSS Formula 3
    Rossa Subscribed Owner

    Apr 28, 2004
    1,255
    #24 MOSS, Feb 6, 2020
    Last edited: Feb 6, 2020
    You may be waiting because Brian is probably doing a PPI right now instead of talking about it. If you think that was an attack then you don't know me very well. If you also think your degree makes a hill of beans difference on the subject we were discussing
    then you live in a vacuum.

    If you don't do evaluations for exotics on a regular business then I would imagine your being a mechanical engineer carrys little weight on this subject and you do not have a valid opinion. Don't let your pride in your education rule here. I speak occasionally with an opinion if I have sound experience on that matter and real practical successful experience. I have built racing engines for 35 years and understand American engine technology well. You will eat crow in a hurry if you think American and Italy parallel each other in that respect. Incidently, "A leakdown test tells you WHY an engine has a compression problem". It does not tell you specifically why. That takes another test. Remember, valves leak back too. Do you know how to test to see which area is leaking? Rings or valve leakage or both? Leak down tests are not for amateurs that have done it once or read how to do it! What is the key factor in getting an accurate leak down result? According to how easy the holes are to get to, this test can take a while to do.....correctly! You may also need a helper to hold the break over bar as the engine trys to rotate. Just an example of how little the ME degree does not play a part. I think its honorable btw, but just not a role player here on this subject.
     
  25. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    Will a leakdown test EVER tell you that an engine with a problematic wet/dry compression test is, in fact, worry free?

    I AGAIN say no.

    Go on... I’ll eat crow if you make that case.

    If not, then enjoy your dish of crow.

    I still say a leakdown test is a waste of time/money on a ppi. But then again.... I’m just an engineer. I don’t make money from ignorant clients.

    Go on... talk of facts WITH BACKUP rather than personal insults.


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