Block interchangability

[jdbubb at ix.netcom.com (Dan Bubb)]

The purpose of the oil squirters is to cool the underside of the piston directly and thereby help heat transfer from the crown of the piston. A cooler crown is a stronger crown.
couple thoughts:
1.  If you think about it the heat path out of the piston crown (where all of the heat is input) is a pretty torturous one. Alot of the heat actually goes out through the top ring and the rest goes out through contact between the piston skirt and cylinder. With a high performance engine and especially with a turbo you can put heat into the piston faster than this crummy heat path can get it out. So, the oil squirter is a way to cool the piston crown directly. As a note; the Formula 1 turbo engines of the mid-80's had an "oil gallery" piston. I don't know what it looks like but sounds like they actually ran the oil around a gallery for maximum heat transfer instead of just shooting it at the bottom.
2..  Cooler piston crown=cooler combustion chamber=less likely to detonate???
3.   Even though the GRM events are pretty short duration, with a high HP turbo engine you can heat up the piston so fast that it's possible to blow it in the course of a 1/4 mile run. Lots of drag racers manage this. VW may have installed the squirters mainly for durability i.e. the piston will just last longer if it always runs cooler, and perhaps to lower piston temps for the comparitivily high CR of the day, but here we're primarily interested in durability in the sense of the piston lasting thru a short race with really high heat input.
Make any sense??
Dan


----- Original Message ----- 
  From: Jeff Toomasson 
  To: Brian McGarvey ; Dan Bubb 
  Cc: GRM Skateboard Racing -- Allyn ; Brian Haygood ; scirocco-l@scirocco.org ; Rick Alexander ; Brett Van Sprewenburg ; Scott F. Williams ; Ron Pieper 
  Sent: Saturday, August 23, 2003 3:55 AM
  Subject: Re: Block interchangability


  'scuse me if I inject a little ignorance here, but why are you so hot to have a block with oil squirters?

  The reason I ask is that you're building this guy for GRM - which is a small series of races? (this is the part I'm unclear of...)

  If the intended purpose of this motor is for a limited duration of use (i.e., one-two-time competition) and you're not looking for durability, how would having the oil squirters make much of a difference over the course of your intended use?

  Just trying to truly define the value of the oil-squirter-deal....

  Jeff

  Brian McGarvey <brianm@earendel.org> wrote:
    THose are the kind of things that we can do.

    Ooooh BTW I need a little advice...

    Turbo choice
    T3/T4 hybrid $300-500 various trims
    K24 $100 (stock UrQ turbo)
    K26 $100 (audi 10vT)

    any suggestions.

    and regarding the squirters etc. is there anything fancy that we have to 
    do?
    brian


    On Mon, 18 Aug 2003, Dan Bubb wrote:

    > >From the table Allyn listed it looks like all will work.
    > But, doesn't the G60 have oil squirters for the pistons? And if you're
    > aiming for big power that means lots of boost, so you really want the
    > squirters. Means you'd need to put all the goodies into a 16V block.
    > Dan
    > ----- Original Message -----
    > From: "Brian McGarvey" 
    > To: "GRM Skateboard Racing -- Allyn" ; "bigmac"
    > ; "Brett Van Sprewenburg" ; "Brian
    > Haygood" ; "Dan Bubb" ; "Rick
    > Alexander" ; "Ron Pieper" ;
    > "Scott F. Williams" 
    > Cc: 
    > Sent: Sunday, August 17, 2003 11:34 PM
    > Subject: Block interchangability
    > 
    > 
    > > Hey ya'll
    > > This is a GRM cheapass question..
    > > the G60 block i got is prolly crap, but the pistons, rods, and crank are
    > > prolly salvagable. So my question is
    > >
    > > if i get one of the readily available, 1.8L 16v or 8v blocks that are
    > > often available free or very cheap, can I swap the crank, rods, and
    > > pistons into the block? Cheapass Racing wants to know...
    > >
    > >
    > >
    > > --
    > > -------------------------------------------------------------
    > > Brian
    > > 88 16v $2004 GRM challenge car http://www.grmotorsports.com
    > > 84 0v Next years car got parts?
    > > 82 2.0L Topless bunny -- Knock Ignition and bigger clutch. next.
    > > 90 90q20v doing daily driver duty.
    > > 91 VFR750F everybody needs a 11-12 sec vehicle.
    > >
    > > Contact method. Email me for AIM, ICQ, YahooIM, IRC, etc.
    > > -------------------------------------------------------------
    > >
    > >
    > > _______________________________________________
    > > Scirocco-l mailing list
    > > Scirocco-l@scirocco.org
    > > http://neubayern.net/mailman/listinfo/scirocco-l
    > 
    > 

    -- 
    -------------------------------------------------------------
    Brian 
    88 16v $2003 GRM challenge car http://www.grmotorsports.com
    84 0v Next years car got parts?
    82 2.0L Topless bunny -- Knock Ignition and bigger clutch. next.
    90 90q20v doing daily driver duty. 
    91 VFR750F everybody needs a 11-12 sec vehicle.

    Contact method. Email me for AIM, ICQ, YahooIM, IRC, etc.
    -------------------------------------------------------------


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