180 degree headers WAS:Re: Turbo header design

[Shannen Durphey]

diy_efi at efi332.eng.ohio-state.edu wrote:
> 
> I've got a car and a bike (both 4 cyl) with 180 degree cranks.  If you're
> interested.
> 
Thanks.  Greg H was kind enough to help.
Shannen
> rick
> 
> > -----Original Message-----
> > From: Shannen Durphey [SMTP:shannen at grolen.com]
> > Sent: Friday, January 08, 1999 12:38 AM
> > To:   diy_efi at efi332.eng.ohio-state.edu
> > Subject:      Re: 180 degree headers WAS:Re: Turbo header design
> >
> > diy_efi at efi332.eng.ohio-state.edu wrote:
> > >
> > > <snipperoo>
> > >
> > > >Clarence,
> > > >  This is easily done with an inline four having a 1-3-4-2 firing
> > order,
> > > >as you just pair cyl's 1-4 and 2-3 together.  Commonly done in NA
> > > >headers and OEM manifolds too.  However, true 180 degree headers on a
> > V8
> > > >typically take up a lot of space.
> > > >   The only firing order i am familiar with is for a GM engine, which
> > is
> > > >1-8-4-3-6-5-7-2.  Picture the cyliders as two rows (which they are):
> > > >
> > > >     1     2        you can see that #1's 180 degree partner is #6,
> > #8's
> > > >     3     4        is #5, #4's is #7 and #3's is #2.
> > > >     5     6
> > > >     7     8
> > >
> > > #1 and #6 are 180 degrees apart on the distributor, not the crank. #1
> > and #4
> > > are 180 degrees apart on the crank. Aren't they? What cylinders are
> > grouped
> > > together with NASCAR 180 degree headers?
> > >
> > > Jon
> > >
> > > <snip>
> > Suppose it would make things easier to include "cam" or "crank". #6
> > is  180 cam degrees from #1.  Means that #8 reaches TDC at 630 crank
> > degrees.
> >
> > Anyone willing to answer some "flat" crank questions off list?
> > Shannen