[DeTomaso] Seat Belt Options- Planning ahead for Pocono

[Guy Dellavecchia]

I don't understand all the math involved, but if an engine has both primary
and secondary balance it is sometimes called "inherently balanced".  Primary
balance is being able to both balance the up and down movement of the
pistons with counterweights on the crank that don't themselves create
vibrations that cannot be offset.  A 90 degree V twin can have primary
balance I believe, so can an inline four.

Secondary balance is where you can counteract the difference between the
piston motion and the sinusoid it would be if not for the connecting rods.
An easy way to see this is to mentally replace the connecting rod with a
Scotch yoke mechanism, that piston motion would then be a sinusoid and not
create a secondary imbalance.  This vibration is 2X the rpm, hence separate
balance shafts in many engines turning 2X crank speed.

By rote memory, inline six, V-8 with 90 degree crank, 60 deg V-6 and V-12
can all have primary and secondary balance without separate balance shafts.
4 cyl inline and V-8 with flat crankshaft cannot.

Or so it seems to me.

The Bosch handbook has many diagrams and formulas about this too.

Guy D.

> I've read this a number of times, and probably understood it at one point,
> but can someone go over why either and in-line 6 or a V12 is an inherently
> balanced engine?
>
> Ken
>
> ----- Original Message -----
> From: "Mc Mullen, Mirril, SOBUS" <mmcmullen@att.com>
> To: <LaurieFerrari@aol.com>; <scottcar@scottcar.org>; "Ken Green"
> <keninsocal@home.com>
> Cc: "Detomaso List" <detomaso@realbig.com>
> Sent: Wednesday, January 09, 2002 12:50 PM
> Subject: RE: [DeTomaso] Seat Belt Options- Planning ahead for Pocono
>
>
> Hey,
>
> Of course it works!
>
> GM went back to the design that BMW always new was the best way to go....
> Straight 6 !!!!
>
> Mirril M. McMullen
> AT&T Solutions
> *  mmcmullen@att.com
> *212-647-3023
> &Pager# 888-merril0 (637-7450)
>      AIM MirrilM
>
>
> > ----------
> > From: Ken Green[SMTP:keninsocal@home.com]
> > Sent: Wednesday, January 09, 2002 10:35 AM
> > To: LaurieFerrari@aol.com; scottcar@scottcar.org
> > Cc: DeTomaso@realbig.com
> > Subject: Re: [DeTomaso] Seat Belt Options- Planning ahead for Pocono
> >
> > charset="iso-8859-1"
> >
> > Laurie,
> >
> > How about a report on the Trailblazer.  The engine is a big departure
from
> > typical Chebby.  i.e., an in line 6, DOHC, variable valve timing?  Does
it
> > all work?
> >
> > Ken
> >
> > ----- Original Message -----
> > From: <LaurieFerrari@aol.com>
> > To: <scottcar@scottcar.org>
> > Cc: <DeTomaso@realbig.com>
> > Sent: Wednesday, January 09, 2002 7:26 AM
> > Subject: Re: [DeTomaso] Seat Belt Options- Planning ahead for Pocono
> >
> >
> > > Aww that's cute... all you say is correct excepting one thing.... you
> are
> > > nowhere's near a pip-squeak to someone who is 5'2" (in tall shoes) ...
> > more
> > > like a giant : )  hehe.  Just seeing if you were awake...love ribbin'
> the
> > > FORD  boyz. I've been in one of yours (little Bro. in SD had one
before
> he
> > > got the Camero SS (which he loves, by the way) and 4 seats are handy
> > indeed).
> > > Regards,
> > > Laurie  (big shot now who now can seat 5-7 depending on size & weight,
> in
> > new
> > > Trailblazer.... much fun racing all the other stoopid SUV's I've
always
> > > hated..& now I'm one of them).
> >
>
> --------------------------------------------------------------------------
> > ----
> > >
> > > -------------------------------------------
> > >
> > > In a message dated 1/9/2002 5:33:52 AM Pacific Standard Time,
> > > scottcar@scottcar.org writes:
> > >
> > > << Subj:     RE: [DeTomaso] Seat Belt Options- Planning ahead for
Pocono
> > >  Date:  1/9/2002 5:33:52 AM Pacific Standard Time
> > >  From:  scottcar@scottcar.org (Scott Carpenter)
> > >  To:    LaurieFerrari@aol.com
> > >  CC:    detomaso@realbig.com
> > >  Laurie,
> > >  Nah, the pre-2001 Cobras have crappy seats (no side support) and the
> fact
> > >  that I am a pipsqueak.. (only 5' 6ish") ;-) They seem to have fixed
it
> > with
> > >  the 2001 Cobra. So I'll eventually put those seats in... other than
> that
> > the
> > >  car is a blast.. Maybe not up to par with a C-5 but definately as
good
> or
> > >  better than any of the earlier Vettes... and cheaper too... Plus I
need
> > to
> > >  have at least something that seats four.  I've got two little ones...
> My
> > >  five year old has already informed me that he wants the Pantera when
he
> > is
> > >  old enough to drive... :-D
> > >
> > >  Scott >>
> > > _______________________________________________
> > > DeTomaso mailing list
> > > DeTomaso@realbig.com
> > > http://realbig.com/mailman/listinfo/detomaso
> > >
> >
> > _______________________________________________
> > DeTomaso mailing list
> > DeTomaso@realbig.com
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> >
>
>
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