Exhaust Manifolds

Rich Kinas

Member
Jul 30, 2019
110
1
18
So I finally got both my manifolds off (no broken bolts). Yipee! Got them both sand blasted (no cracks), osphod and painted with 2000 deg flat black
paint. Interesting drivers is a 76 manifold and passengers is a 73. Although they have the same shape, (Mr. obvious speaking) they do look quite
different. Are there any specific reasons one would be concerned in running this configuration, two different year exhaust manifolds? I sure cant
think of any, just thought I would ask, just to be sure.

Obviously the passenger manifold bit the dust some time in the past. Interesting also is that the front bolt for the passenger was larger, must have
broken in the past, drilled out and tapped to a larger bolt size. I doubt this was original. So getting all the surfaces cleaned up then going to
check for flatness. More rain this afternoon in Orlando, which keeps interrupting my progress.

Rich
--
Rich Kinas
1976 Elaganza II
Orlando, FL
 
They must be from the Toronado as it is front wheel drive.

On Mon, Oct 21, 2019 at 2:51 PM Rich Kinas via Gmclist <

> So I finally got both my manifolds off (no broken bolts). Yipee! Got them
> both sand blasted (no cracks), osphod and painted with 2000 deg flat black
> paint. Interesting drivers is a 76 manifold and passengers is a 73.
> Although they have the same shape, (Mr. obvious speaking) they do look quite
> different. Are there any specific reasons one would be concerned in
> running this configuration, two different year exhaust manifolds? I sure
> cant
> think of any, just thought I would ask, just to be sure.
>
>
> Obviously the passenger manifold bit the dust some time in the past.
> Interesting also is that the front bolt for the passenger was larger, must
> have
> broken in the past, drilled out and tapped to a larger bolt size. I doubt
> this was original. So getting all the surfaces cleaned up then going to
> check for flatness. More rain this afternoon in Orlando, which keeps
> interrupting my progress.
>
> Rich
> --
> Rich Kinas
> 1976 Elaganza II
> Orlando, FL
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
The two manifolds are pretty different in any case because the left one has
to work around the transmission.

Rick “not thinking they changed over the years” Denney

On Mon, Oct 21, 2019 at 5:51 PM Rich Kinas via Gmclist <

> So I finally got both my manifolds off (no broken bolts). Yipee! Got them
> both sand blasted (no cracks), osphod and painted with 2000 deg flat black
> paint. Interesting drivers is a 76 manifold and passengers is a 73.
> Although they have the same shape, (Mr. obvious speaking) they do look quite
> different. Are there any specific reasons one would be concerned in
> running this configuration, two different year exhaust manifolds? I sure
> cant
> think of any, just thought I would ask, just to be sure.
>
>
> Obviously the passenger manifold bit the dust some time in the past.
> Interesting also is that the front bolt for the passenger was larger, must
> have
> broken in the past, drilled out and tapped to a larger bolt size. I doubt
> this was original. So getting all the surfaces cleaned up then going to
> check for flatness. More rain this afternoon in Orlando, which keeps
> interrupting my progress.
>
> Rich
> --
> Rich Kinas
> 1976 Elaganza II
> Orlando, FL
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
'73 X-Glacier 230 "Jaws"
Northern Virginia
Offlist email: rick at rickdenney dot com
 
Ok Interesting...I'll take a picture of both tonight and post so we can all
take a look and see if we can figure it out. I'm going to put them back on,
I just like to know all the ins and outs of my coach.

Rich

On Mon, Oct 21, 2019 at 7:02 PM Richard Denney via Gmclist <

> The two manifolds are pretty different in any case because the left one has
> to work around the transmission.
>
> Rick “not thinking they changed over the years” Denney
>
> On Mon, Oct 21, 2019 at 5:51 PM Rich Kinas via Gmclist <

>
> > So I finally got both my manifolds off (no broken bolts). Yipee! Got them
> > both sand blasted (no cracks), osphod and painted with 2000 deg flat
> black
> > paint. Interesting drivers is a 76 manifold and passengers is a 73.
> > Although they have the same shape, (Mr. obvious speaking) they do look
> quite
> > different. Are there any specific reasons one would be concerned in
> > running this configuration, two different year exhaust manifolds? I sure
> > cant
> > think of any, just thought I would ask, just to be sure.
> >
> >
> > Obviously the passenger manifold bit the dust some time in the past.
> > Interesting also is that the front bolt for the passenger was larger,
> must
> > have
> > broken in the past, drilled out and tapped to a larger bolt size. I doubt
> > this was original. So getting all the surfaces cleaned up then going to
> > check for flatness. More rain this afternoon in Orlando, which keeps
> > interrupting my progress.
> >
> > Rich
> > --
> > Rich Kinas
> > 1976 Elaganza II
> > Orlando, FL
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> --
> '73 X-Glacier 230 "Jaws"
> Northern Virginia
> Offlist email: rick at rickdenney dot com
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
The date code is present on all GM product castings and forgings, clear
back to at least the 1950's. They might make a part identical for several
years, but the date code changes frequently. "P.I.T.A. Purists that restore
GM vehicles want everything exactly period correct. That goes to things
like windshield glass, fasteners, headlights, you name it. Such is the
state of the art on the show circuit. My last show car, a 1961 Cadillac
small roof 2 door hardtop DeVille, was judged in a number of national
concours shows, got points knocked off for replacement headlamps.
Picky, picky, picky. Never enjoyed that part of the show circuit. Every
time we drove it to an event, I hovered next to it like an expectant
father. Takes some of the enjoyment out of it, for sure.
So, your manifold easily could have been made later than the coach,
but be identical in every respect. Functions exactly the same. Don't spend
another second thinking about stuff like that. Drive it with your family,
make some lasting memories, have a great time in it. My take on it, anyhow.
But, if your coach is one of the only Five (5 ea.) Coca-Cola/Pepsi
comparison challenge contest prize coaches, you are going to want period
correct, all numbers matching components from bumper to bumper. They are
the only significant GMC's ever made, and clones abound. Just like the
EM-50 from the movie Stripes.
Jim Hupy
Salem, Oregon

On Tue, Oct 22, 2019, 4:13 AM Rich Kinas via Gmclist <

> Ok Interesting...I'll take a picture of both tonight and post so we can all
> take a look and see if we can figure it out. I'm going to put them back on,
> I just like to know all the ins and outs of my coach.
>
> Rich
>
> On Mon, Oct 21, 2019 at 7:02 PM Richard Denney via Gmclist <

>
> > The two manifolds are pretty different in any case because the left one
> has
> > to work around the transmission.
> >
> > Rick “not thinking they changed over the years” Denney
> >
> > On Mon, Oct 21, 2019 at 5:51 PM Rich Kinas via Gmclist <

> >
> > > So I finally got both my manifolds off (no broken bolts). Yipee! Got
> them
> > > both sand blasted (no cracks), osphod and painted with 2000 deg flat
> > black
> > > paint. Interesting drivers is a 76 manifold and passengers is a 73.
> > > Although they have the same shape, (Mr. obvious speaking) they do look
> > quite
> > > different. Are there any specific reasons one would be concerned in
> > > running this configuration, two different year exhaust manifolds? I
> sure
> > > cant
> > > think of any, just thought I would ask, just to be sure.
> > >
> > >
> > > Obviously the passenger manifold bit the dust some time in the past.
> > > Interesting also is that the front bolt for the passenger was larger,
> > must
> > > have
> > > broken in the past, drilled out and tapped to a larger bolt size. I
> doubt
> > > this was original. So getting all the surfaces cleaned up then going to
> > > check for flatness. More rain this afternoon in Orlando, which keeps
> > > interrupting my progress.
> > >
> > > Rich
> > > --
> > > Rich Kinas
> > > 1976 Elaganza II
> > > Orlando, FL
> > >
> > > _______________________________________________
> > > GMCnet mailing list
> > > Unsubscribe or Change List Options:
> > > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> > >
> > --
> > '73 X-Glacier 230 "Jaws"
> > Northern Virginia
> > Offlist email: rick at rickdenney dot com
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
I saw a pair of Road Runners judged down to the color of the battery caps which changed from year to year, some yellow, some orange. I think yellow
won out over the other car. I'd much rather just drive them with an aftermarket battery.

--johnny

--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
Here is a link to a picture of the exhaust manifolds that are on my 76
Eleganza, sand blasted and painted with 2000 deg F paint.
I assume the drivers manifold date code is 1216 which I guess is Jan 21,
1976, and the passenger manifold looks like a 73 date code. Are they
supposed to look this different?

http://www.gmcmhphotos.com/photos/member-galleries/p66783-76-exhaust-manifolds.html

Rich

On Wed, Oct 23, 2019 at 9:24 AM Johnny Bridges via Gmclist <

> I saw a pair of Road Runners judged down to the color of the battery caps
> which changed from year to year, some yellow, some orange. I think yellow
> won out over the other car. I'd much rather just drive them with an
> aftermarket battery.
>
>
> --johnny
>
> --
> Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> I forgive them all, save those who hurt the dogs. They must answer to me
> in hell
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
If you are asking if L/R are supposed to be simple mirror image, they are not. The exhaust pipes are quite different as well, to have the end at the
muffler inlets relatively equal.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
The right or passenger exhaust is unique to the 455 as installed in the motorhome. The Toronado manifold will not work easily.
I know you did not ask, but the middle bolt on the exhaust manifolds exist to hold the manifold in place while getting the other 4 bolts installed. Do
not torque it down, torqueing it down will cause a tilt towards the top and result in leaks out the bottom of the joint.
I suggest RemFlex gaskets be used. Follow the RemFlex directions as to torque amounts and tighting pattern. Remember to re-torque the manifolds after
driving the coach.
Tom
--
2012 Phoenix Cruiser model 2552
KA4CSG
 
You are experiencing some of the issues of dealing with 40+ year old
machinery. Cast Iron cracks with age, that is a fact of life. Can't change
that. Add engine exhaust gas temperatures to that equation, and you speed
up the process. Many, many 455 exhaust manifolds have already succumbed to
cracking, and the supply of motorhome and toronado components available is
dwindling quickly. Hoarders have salvaged nearly any and all of them, and
are reluctant to part with any. That is why many of us use headers. They
work well, properly installed.
Jim Hupy
Salem, Oregon

On Thu, Oct 24, 2019, 7:58 AM Thomas Phipps via Gmclist <

> The right or passenger exhaust is unique to the 455 as installed in the
> motorhome. The Toronado manifold will not work easily.
> I know you did not ask, but the middle bolt on the exhaust manifolds exist
> to hold the manifold in place while getting the other 4 bolts installed. Do
> not torque it down, torqueing it down will cause a tilt towards the top
> and result in leaks out the bottom of the joint.
> I suggest RemFlex gaskets be used. Follow the RemFlex directions as to
> torque amounts and tighting pattern. Remember to re-torque the manifolds
> after
> driving the coach.
> Tom
> --
> 2012 Phoenix Cruiser model 2552
> KA4CSG
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>