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Thread: crank scrapers- anything in it

  1. #31
    Junior Member Domestic Engineer
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    Default Re: crank scrapers- anything in it

    Quote Originally Posted by The Real Roadrunner
    that is like saying dry sumps are a waste of time
    The purpose of Dry sumps is different to that of Crank scrappers....

  2. #32
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    Default Re: crank scrapers- anything in it

    that was an analogy,

    they both have there uses and benefits depending on what purpose your building the engine for.

  3. #33
    Junior Member Too Much Toyota oldcorollas's Avatar
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    Default Re: crank scrapers- anything in it

    Quote Originally Posted by abently
    The purpose of Dry sumps is different to that of Crank scrappers....
    err... they both are trying to reduce the amount of oil flinging around (and the DS with added reliability of oiling etc)

    if it was of benefit to have oil around the crank.. dry sumps would be run such that there was always some oil in the sump, and no windage tray....
    "I'm a Teaspoon, not a mechanic"
    "There is hardly anything in the world that a man can not make a little worse and sell a little cheaper" - John Ruskin (1819 - 1900)

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  4. #34
    Junior Member Automotive Encyclopaedia
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    Default Re: crank scrapers- anything in it

    WOW! I thought this latest thing Sam_Q has stumbled upon would only be about the 'bang for the bucks' of Teflon, but someone seems to be on stupid/annoying pills or crack!

  5. #35
    Junior Member Domestic Engineer
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    Default Re: crank scrapers- anything in it

    How much do these off-the-shelf crank scrappers cost ?

    Here, I'll give a real 5% extra HP for nothing.

    http://www.maxracesoftware.com/pipemax36xp2.htm

    Its been developed on 20years of theory and real-world data. Best $60 you'll spend.

    I have the Lotus Engine Simulation program Renault use to design their F1 Engines but its a lot more involved for only results which are slightly more accurate....

  6. #36
    Junior Member Domestic Engineer
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    Default Re: crank scrapers- anything in it

    Should say, its designed around the exhaust Harmonics of N/A Engines.

  7. #37
    Junior Member Too Much Toyota oldcorollas's Avatar
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    Default Re: crank scrapers- anything in it

    perhaps you should read "the scientific design of intake and exhaust systems" by P.Smith

    edit: and you are the first to mention teflon
    "I'm a Teaspoon, not a mechanic"
    "There is hardly anything in the world that a man can not make a little worse and sell a little cheaper" - John Ruskin (1819 - 1900)

    AU$TRALIA... come and stay and PAY and PAY!!! The moral high horse of the world!

  8. #38
    Sucks to be a Domestic Engineer YelloRolla's Avatar
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    Default Re: crank scrapers- anything in it

    Abently - The question is about gains from a proper crank scraper - is there a gain or not? Nothing you have provided tells us that there will be a loss (with the exception of a vague notion that the wrist pin will suffer from more friction, which is ludicrous).

    The program in the link looks very good - thanks for that, but it is not relevant in this discussion.
    YelloRolla's KE20 1/4mi = 11.32 @ 119mph @ 22psi on slicks
    12.44 @ 113 mph on 165 wide street tyres
    210rwkw - not bad for a smelly 3TGTE running pump fuel.

  9. #39
    But I have no carport? Carport Converter merc-blue's Avatar
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    Default Re: crank scrapers- anything in it

    depends on the engine, if you have a stock engine with nothing special then you not going to notice,
    but if your running a 4AGE up to 9KRPM pushing max HP out of it in a sport sedan than yes a scraper will help
    I know that most big revving small engine open wheelers notice good HP benefits from them
    I would also like to say that its a good bang for your buck, when your building top end engines,
    I know our BD series ford engines that are nearing 300HP from between 1600-2000cc as far as total cost of a engine goes we would love to pay a grand for 3HP
    breaking that loverly 300HP figure would be great,

  10. #40
    Junior Member Domestic Engineer
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    Default Re: crank scrapers- anything in it

    Quote Originally Posted by YelloRolla
    Abently - The question is about gains from a proper crank scraper - is there a gain or not?
    It depends too much on the Engine particulars..... just build one, fit it and be happy with the knowledge that if their was Hp to gain, you have done so.

  11. #41
    Senior ****** Carport Converter Sam_Q's Avatar
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    Default Re: crank scrapers- anything in it

    ok thanks guys, I think I will give it a miss

  12. #42
    Senior ****** Carport Converter Sam_Q's Avatar
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    Default Re: crank scrapers- anything in it

    I had a polite email sent to me from Ishihara-Johnson Crank Scrapers. he couldnt post on here because it would be considered advertising and I am hopig I am not breaking any rules by quoting him


    Before I forget, the windage tray in the 4A is very similar in design to that of the OEM one in the big block Chrysler.* That tray was put into service almost 40 years ago.* Dyno testing and drag racing use of our scrapers in that app has been very, very successful.* Hopefully this will dispell the notion that the OEM piece in the 4A is optimal even with the longitudinal versus transverse mounting issues.* There is a good reason I add internal screening to the trays -- high speed oil droplets bounce off the interior of smooth metal trays and are hit again and again.*

    * The wrist pin issue -- there are wrist pin issues with some engines in low pressure sumps.* The threshold appears to be 15" of vacuum.* The reason why appears very straight forward: In stock engines, most piston pin oiling comes from the oil scraper rings that collect oil from the cylinder walls.* As ambient pressures decrease the windage effects decrease -- in the 4A, pumping between 1-2 and 3-4 bays as well as rotational.* The oil spray patterns from the rods and mains revert to their ideal, i.e. radially and tangentially.* These patterns are orthogonal to the cylinder wall sections where the piston ring scrapers collect oil.* Very simple.

    * To increase oiling to the pin simply direct a spray to the inner area of the piston.* Many ways to do this.* Cheapest and simplest is to add a groove to either side of the rod big end faces aimed directly up the beam.* Old trick from motorcycle engines.* OEMs often do the same thing but typically directed towards the thrust face of the cylinder.


    In any event, by disrupting the pressure differential that actively draws oil into it more oil will be released to follow its normal path -- i.e. there should be an increase in pin oiling rather than a decline.* The caveats still hold about 15" and higher of sump vacuum.

    *

    As for other issues with the oiling system in the 4A, a very fundamental problem is the distance of the pickup from the sump floor.* A racer in Australia, Wayne Walker, has measured that out to be close to an inch or 25mm.* Ford Motorsports recommends .250" to .375".* Vast difference there.* The pickup is more likely to be exposed bcause of this in high Gs because of the intersection of the angle of repose of the oil at its surface and the edge of the opening of the pickup tube in the screening bulb.* Very straight foward issue.* It also makes it more likely that the pickup will draw in foamed oil sitting on the surface of the neat oil.* The rods will only endure up to about 30% entrained air; mains 50%.* This angle of repose issue also arises in the 1ZZ and 2ZZ engines where the wetsump has a 1G design limit.* It also arises in the M series of straight six engines.

    *

    I am currently working on a dual scraper system for the 4A used in the Toyota Atlantic engines.* Because of the clearance issues with the dry sump pan the scraper will mount along the main caps.* I am also making a number of baffles to go with it.* There will also be a bolt in scavenging system for the TRD pan.

    *

    Kind regards,

    *

    Kevin Johnson

    *

    Ishihara-Johnson Crank Scrapers
    http://www.crank-scrapers.com
    Land O' Lakes, Florida
    727-808-8602

    anyone got any comments on this?

  13. #43
    Forum Sponsor Conversion King
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    Default Re: crank scrapers- anything in it

    all seems pretty legit from this side of the fence.
    cheers
    linden

  14. #44
    Junior Member Grease Monkey
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    Default Re: crank scrapers- anything in it

    Seems like there are a lot of people here talking about something they have no first hand knowledge or experience of, and try to make out what they are saying is fact.

    There are benefits with windage trays and crank scrapers if designed correctly !
    Are they cost effective ?
    On a beer budget - probably not, that is until the engine expires from aerated oil, excessive oil temps, oil surge etc.

  15. #45
    Junior Member Grease Monkey
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    Default Re: crank scrapers- anything in it

    I do believe there are benfits to be had from a properly setup crank scraper, but there only small. I read up a fair bit on them about 4 years ago, so I can't remember where the stuff is now, but I never heard of any problems with problems with the wrist pins before.

    Quote Originally Posted by ed_jza80
    i whole heartedly disagree, and can cite engines before and after crank craper/windage control installation netting around 15hp on a 500hp engine
    If you do the maths it comes out to a 3% gain, so if your only pushing out little horsepower, it not really worth it. If your pushing out big numbers, then you've already spent a crap load, so who cares about a little more to make the number get bigger

    If you've got a 4AGE, and you build it with an aftermarket computer with a decent tune, 272 cams, and get the head ported, and a few other little bits, you'll be pushing 160hp (see http://www.billzilla.org/4agmods.htm). So the most gain you'll get would be 5hp (4.8 if you want to be exact ), but I imagine the pretty decent stock steup would already be getting you this horsepower

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