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Header wrap [message #131849] Fri, 24 June 2011 13:01 Go to next message
biggreen is currently offline  biggreen   United States
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Registered: June 2011
Location: Northeast Florida
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I've decided on headers since my exhaust manifolds leak and are corroded. I've read not to waste $ on ceramic coating as it will burn off in time. I have used a wrap on headers for muscle and race cars in the past. Anyone use this in a GMC? I would think it would help keep the heat down. Thanks
Re: [GMCnet] Header wrap [message #131855 is a reply to message #131849] Fri, 24 June 2011 13:29 Go to previous messageGo to next message
Gary Worobec is currently offline  Gary Worobec   United States
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Senior Member
Hi,
I would disagree on the ceramic coating. Today's stuff is pretty good. I've
also heard that header wrap can trap moisture and cause rusting more
quickly. Doug's (Thorley) Headers are coated and they make a set just for
the GMC. Check with Jim K.

Thanks

Gary and Joanne Worobec
1973 GMC Glacier
Anza, CA

----- Original Message -----
From: "R.D. Hart" <regor5556@yahoo.com>
To: <gmclist@temp.gmcnet.org>
Sent: Friday, June 24, 2011 11:01 AM
Subject: [GMCnet] Header wrap


>
>
> I've decided on headers since my exhaust manifolds leak and are corroded.
> I've read not to waste $ on ceramic coating as it will burn off in time.
> I have used a wrap on headers for muscle and race cars in the past.
> Anyone use this in a GMC? I would think it would helC GMp keep the heat
> down. Thanks
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

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Re: [GMCnet] Header wrap [message #131856 is a reply to message #131849] Fri, 24 June 2011 13:32 Go to previous messageGo to next message
ljdavick is currently offline  ljdavick   United States
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Location: Fremont, CA
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There was a lively discussion about this very thing just a little while ago

If you are on the forum - look here
<http://gmc.mybirdfeeder.net/GMCforum/index.php?t=msg&rid=1199&th=8106&goto=54588#msg_54588>

Uhm, August of 2009? Really? It was just the other day...

Larry Davick
Fremont, California
The Mystery Machine
'76 (ish) Palm Beach


----- Original Message -----
From: "R.D. Hart" <regor5556@yahoo.com>
To: gmclist@temp.gmcnet.org
Sent: Friday, June 24, 2011 11:01:53 AM
Subject: [GMCnet] Header wrap



I've decided on headers since my exhaust manifolds leak and are corroded. I've read not to waste $ on ceramic coating as it will burn off in time. I have used a wrap on headers for muscle and race cars in the past. Anyone use this in a GMC? I would think it would help keep the heat down. Thanks
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A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
Re: Header wrap [message #131858 is a reply to message #131849] Fri, 24 June 2011 13:39 Go to previous messageGo to next message
biggreen is currently offline  biggreen   United States
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Makes sense. My hot rods were never exposed to the elements. So this ceramic coating will last?
Re: Header wrap [message #131861 is a reply to message #131849] Fri, 24 June 2011 13:55 Go to previous messageGo to next message
jaholland is currently offline  jaholland   United States
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Location: Sweet Home Alebamy
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Senior Member
biggreen wrote on Fri, 24 June 2011 13:01

I've decided on headers since my exhaust manifolds leak a
nd are corroded.
I've read not to waste $ on ceramic coating as it will burn off in time.
I have used a wrap on headers for muscle and race cars in the past.
Anyone use this in a GMC?
I would think it would help keep the heat down.
Thanks



===================================================

WRAP ~
The first thing that I did when I got my headers
was to get rid of all that wrap ~ They must have
thought the headers were breakable to have taped
all of that bubble wrayp on them and the box ~
I don't know exactly just what kind of tape they
used but it was almost impossible to cut ~

~ Joe ~


/_]*[__][] *[__|] ~ * '73 TZE063V101887 "
" O----------OO--]* ~ '78 TZE168V100234 "
" " Joe & Lavelle " "
" 'sweet home alebamy'

[Updated on: Fri, 24 June 2011 13:57]

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Re: [GMCnet] Header wrap [message #131862 is a reply to message #131849] Fri, 24 June 2011 13:58 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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There's a set of ceramic coated headers on my son's coach which came
with it in '98. IIRC, the records indicated they'd been on there
since '93. With over 80,000 miles on them, they're still in good
shape.

I would NOT wrap headers because of moisture retention and rusting.

JMHO

Ken H.

On Fri, Jun 24, 2011 at 2:01 PM, R.D. Hart wrote:
>
>
> I've decided on headers since my exhaust manifolds leak and are corroded.  I've read not to waste $ on ceramic coating as it will burn off in time.  I have used a wrap on headers for muscle and race cars in the past.  Anyone use this in a GMC?  I would think it would help keep the heat down.  Thanks
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Header wrap [message #131866 is a reply to message #131858] Fri, 24 June 2011 14:48 Go to previous messageGo to next message
Gary Worobec is currently offline  Gary Worobec   United States
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Ceramic coating will last but why not go with coated Thorley headers. You
would not be able to get a set of decent headers and have them coated for
the same price as Thorleys
http://www.appliedgmc.com/search.itml?icQuery=headers. These have thick
flanges, coated and a designed to fit all for about $600.00

Thanks

Gary and Joanne Worobec
1973 GMC Glacier
Anza, CA


----- Original Message -----
From: "R.D. Hart" <regor5556@yahoo.com>t
To: <gmclist@temp.gmcnet.org>
Sent: Friday, June 24, 2011 11:39 AM
Subject: Re: [GMCnet] Header wrap


>
>
> Makes sense. My hot rods were never exposed to the elements. So this
> ceramic coating will last?
> _______________________________________________
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Re: [GMCnet] Header wrap [message #131867 is a reply to message #131858] Fri, 24 June 2011 14:50 Go to previous messageGo to next message
Gary Worobec is currently offline  Gary Worobec   United States
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Also, don;t think you are going to get more power from a GMC 455 with
headers. It's very close to the same with iron manifolds. There are some
dyno sheets floating around on this.

Thanks

Gary and Joanne Worobec
1973 GMC Glacier
Anza, CA




----- Original Message -----
From: "R.D. Hart" <regor5556@yahoo.com>
To: <gmclist@temp.gmcnet.org>
Sent: Friday, June 24, 2011 11:39 AM
Subject: Re: [GMCnet] Header wrap


>
>
> Makes sense. My hot rods were never exposed to the elements. So this
> ceramic coating will last?
> _______________________________________________
> GMCnet mailing listin
> Unsubscribe or Change List Options:
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Re: [GMCnet] Header wrap [message #131868 is a reply to message #131849] Fri, 24 June 2011 15:06 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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On Fri, Jun 24, 2011 at 11:01 AM, R.D. Hart <regor5556@yahoo.com> wrote:

Mr Thorley, always, did not recommend wrapping the headers. ( it willhold
water and cause them to rust).

He also did not recommend that they be ceramic coated (inside) because it
would come off and go into the engine.

read here
http://www.gmcmotorhome.info/HEADERS.html
gene




--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: Header wrap [message #131881 is a reply to message #131849] Fri, 24 June 2011 18:12 Go to previous messageGo to next message
biggreen is currently offline  biggreen   United States
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Location: Northeast Florida
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I am aware that only Thorley makes the GMC Motorhome headers. Mine is a 403. So opinions are split on the coating. Are they coated on the inside or outside? Also, Gateway sells ceramic coated headers for a few bucks less. I've had good service from Gateway in the past, as I have had from Jim K and Jim B.,and wonder why no one here ever mentions them. Can of worms??
Re: [GMCnet] Header wrap [message #131885 is a reply to message #131862] Fri, 24 June 2011 18:26 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Thorly has now gone 100% to Ceramic coatings as the original nickle
dip was costing them too much.
Doug's headers are doing the same.
Being that our headers stay high enough and not effected by the rocks
hitting them, you'll see that it will survive.
Header manufactures refuse to honor warranty if they have been wrapped.
Keep in mind that only Doug's headers have the 455 flange, the
Thorley's might go there on the next batch,
Doug's come standard with Oxy sensor bungs on each side on the collector.
They are in stock

On Fri, Jun 24, 2011 at 11:58 AM, Ken Henderson <hend4800@bellsouth.net> wrote:
> There's a set of ceramic coated headers on my son's coach which came
> with it in '98.  IIRC, the records indicated they'd been on there
> since '93.  With over 80,000 miles on them, they're still in good
> shape.
>
> I would NOT wrap headers because of moisture retention and rusting.
>
> JMHO
>
> Ken H.
>
> On Fri, Jun 24, 2011 at 2:01 PM, R.D. Hart wrote:
>>
>>
>> I've decided on headers since my exhaust manifolds leak and are corroded.  I've read not to waste $ on ceramic coating as it will burn off in time.  I have used a wrap on headers for muscle and race cars in the past.  Anyone use this in a GMC?  I would think it would help keep the heat down.  Thanks
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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www.appliedgmc.com
1-800-752-7502
Re: Header wrap [message #131886 is a reply to message #131849] Fri, 24 June 2011 18:37 Go to previous messageGo to next message
biggreen is currently offline  biggreen   United States
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So, Jim, do these headers fit a 403?
Re: [GMCnet] Header wrap [message #131888 is a reply to message #131886] Fri, 24 June 2011 18:51 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Yes, and we found no degradation on low end torque when Joe Mondello
did it with a dyno.

On Fri, Jun 24, 2011 at 4:37 PM, R.D. Hart <regor5556@yahoo.com> wrote:
>
>
> So, Jim, do these headers fit a 403?
> _______________________________________________
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>



--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Header wrap [message #131931 is a reply to message #131881] Fri, 24 June 2011 20:19 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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On Jun 24, 2011, at 5:12 PM, R.D. Hart wrote:

>
>
> I am aware that only Thorley makes the GMC Motorhome headers. Mine is a 403. So opinions are split on the coating. Are they coated on the inside or outside? Also, Gateway sells ceramic coated headers for a few bucks less. I've had good service from Gateway in the past, as I have had from Jim K and Jim B.,and wonder why no one here ever mentions them. Can of worms??
Do they have the O2 sensor bung already welded into the end of the header? I believe that Jim K.'s does.

Emery Stora
77 Kingsley
Santa Fe, NM


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Re: [GMCnet] Header wrap [message #131944 is a reply to message #131888] Sat, 25 June 2011 07:12 Go to previous messageGo to next message
Jim Bounds is currently offline  Jim Bounds   United States
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In the initial testing of our Koba Motor program, we did a dyno pull with
headers and with stock manifolds, the results were so close as to not bear
comparison.  There was actually a little rise in torque just off idle with the
original manifolds but like I said it was too small to really note.


You do not install headers for increased performance, the scavange effect
headers give you does not really kick in under 3000 rpm, the main reason you
install them is the cast manifolds are cracking.  Thedriver saide manifold can
only be resurfaced slightly before there is not adequite clearance for the oil
dip stick tue to pass between it and the head.  That along with having a off
pressure 5 bolt pattern, it really is only a matter of time until the manifolds
need to be given a gold watch for their past services.  Every motor we install
gets header sets, I mean if the intent is to offer a reliable drive train,
original manifold simply "CAN'T HOLD THE SMOKE"!  If everything works flawless
but the exhaust manifolds constantly blow out gaskets-- what have you
accomplished.

There are several issues that time has made us address, this is one of them. 
It's a bummer but there it is.  I get my Doug Thorley header sets through Jim
K., I would suggest getting them there as well,

Jim Bounds
-----------------------



----- Original Message ----
From: Jim Kanomata <jimkanomata@gmail.com>
To: gmclist@temp.gmcnet.org
Sent: Fri, June 24, 2011 7:51:30 PM
Subject: Re: [GMCnet] Header wrap

Yes, and we found no degradation on low end torque when Joe Mondello
did it with a dyno.

On Fri, Jun 24, 2011 at 4:37 PM, R.D. Hart <regor5556@yahoo.com> wrote:
>
>
> So, Jim, do these headers fit a 403?
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>



--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Re: Header wrap [message #131971 is a reply to message #131849] Sat, 25 June 2011 12:48 Go to previous messageGo to next message
Larry C   United States
Messages: 1168
Registered: July 2004
Location: NE Illinois by the Illino...
Karma: 0
Senior Member
When I purchased Gatsbys' CRUISER Very Happy The Manifold exh gasket had been replaced. By the time I returned home, about 2000 miles, they were blown out again. Sounded like a truck.

My mechanic thought it was just a simple gasket replacement. I blew that one out in 1400 miles.

I then used REMFLEX gaskets and has held ever since. Cheaper than headers and a new exhaust system to match it.

JimB also has developed a system where he glues the gasket in which seems to work well also.

I have wondered if it would be worth while to wrap the exhaust where the tranny over flow would pour out fluid. Anything to keep from flaming up.


my thought


Gatsbys' CRUISER 08-18-04
74 GLACIER X, 260/455-APC-4 Bagg'r
Remflex Manifold gaskets
CampGrounds needed, Add yours to "PLACES" /> http://www.gmceast.com/travel
_
Re: [GMCnet] Header wrap [message #131977 is a reply to message #131944] Sat, 25 June 2011 13:31 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Location: Belmont, CA
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I have seen the data that Jerry Jarden and Doug Thorly published back in 1995.
It was done with an comparison on the dyno with closed system and also open.
As I remember, there was a gain from 2,000-2900.
They were using the 0ne that was designed for 403 engine as Jerry
Jarden had a 78 MH.
Now we have Doug"s headers from Pertronics that are designed for use
on both 403 and 455.
The late Joe Mondello told me that the new one showed increase in the
range from 2,000-3200.


On Sat, Jun 25, 2011 at 5:12 AM, Jim Bounds <gmccoop@yahoo.com> wrote:
> In the initial testing of our Koba Motor program, we did a dyno pull with
> headers and with stock manifolds, the results were so close as to not bear
> comparison.  There was actually a little rise in torque just off idle with the
> original manifolds but like I said it was too small to really note.
>
>
> You do not install headers for increased performance, the scavange effect
> headers give you does not really kick in under 3000 rpm, the main reason you
> install them is the cast manifolds are cracking.  Thedriver saide manifold can
> only be resurfaced slightly before there is not adequite clearance for the oil
> dip stick tue to pass between it and the head.  That along with having a off
> pressure 5 bolt pattern, it really is only a matter of time until the manifolds
> need to be given a gold watch for their past services.  Every motor we install
> gets header sets, I mean if the intent is to offer a reliable drive train,
> original manifold simply "CAN'T HOLD THE SMOKE"!  If everything works flawless
> but the exhaust manifolds constantly blow out gaskets-- what have you
> accomplished.
>
> There are several issues that time has made us address, this is one of them.
> It's a bummer but there it is.  I get my Doug Thorley header sets through Jim
> K., I would suggest getting them there as well,
>
> Jim Bounds
> -----------------------
>
>
>
> ----- Original Message ----
> From: Jim Kanomata <jimkanomata@gmail.com>
> To: gmclist@temp.gmcnet.org
> Sent: Fri, June 24, 2011 7:51:30 PM
> Subject: Re: [GMCnet] Header wrap
>
> Yes, and we found no degradation on low end torque when Joe Mondello
> did it with a dyno.
>
> On Fri, Jun 24, 2011 at 4:37 PM, R.D. Hart <regor5556@yahoo.com> wrote:
>>
>>
>> So, Jim, do these headers fit a 403?
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>>
>
>
>
> --
> Jim Kanomata
> Applied/GMC, Fremont,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
> _______________________________________________
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>
> _______________________________________________
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>



--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Header wrap [message #132036 is a reply to message #131971] Sat, 25 June 2011 22:39 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Larry,

If you're talking about the vent I reckon it would be easier to install:

http://www.appliedgmc.com/prod.itml/icOid/866

Ken Frey installed a 90° air line fitting in Double Trouble. He said there
was just enough room to get a tap in there and he greased it to hold the
sworf. It must have been OK as I've put about 12K miles on since he did it.


Regards,
Rob M.
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426


-----Original Message-----
From: Larry

I have wondered if it would be worth while to wrap the exhaust where the
tranny over flow would pour out fluid. Anything to keep from flaming up.

my thought
--
Gatsbys' CRUISER :d
74 GLACIER X, 260
455/APC/4 bagg'r(ver3)
Remflex Manifold gaskets

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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Header wrap [message #132077 is a reply to message #132036] Sun, 26 June 2011 09:31 Go to previous messageGo to next message
Arthur Mansfield is currently offline  Arthur Mansfield   United States
Messages: 290
Registered: April 2010
Karma: 0
Senior Member
What is the affect of grinding the bump put of the exhaust port of the heads. Does it reduce the low end torque or what? I have a set of heads that these were ground out of. In fact because of a cracked head one of these is on the engine now. Well I am assuming cracked head since it leaked water and filled a cylinder with water. The head had been milled flat when I had a valve job done on it.

Art & Doris
EL 76
On Jun 25, 2011, at 10:39 PM, Rob Mueller wrote:

> Larry,
>
> If you're talking about the vent I reckon it would be easier to install:
>
> http://www.appliedgmc.com/prod.itml/icOid/866
>
> Ken Frey installed a 90° air line fitting in Double Trouble. He said there
> was just enough room to get a tap in there and he greased it to hold the
> sworf. It must have been OK as I've put about 12K miles on since he did it.
>
>
> Regards,
> Rob M.
> Sydney, Australia
> AUS '75 Avion-The Blue Streak TZE365V100428
> USA '75 Avion-Double Trouble TZE365V100426
>
>
> -----Original Message-----
> From: Larry
>
> I have wondered if it would be worth while to wrap the exhaust where the
> tranny over flow would pour out fluid. Anything to keep from flaming up.
>
> my thought
> --
> Gatsbys' CRUISER :d
> 74 GLACIER X, 260
> 455/APC/4 bagg'r(ver3)
> Remflex Manifold gaskets
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

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Re: [GMCnet] Header wrap [message #132079 is a reply to message #132077] Sun, 26 June 2011 09:41 Go to previous messageGo to previous message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
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Senior Member
Depending on which tuner that you believe, and the combination of heads,
manifolds, headers, cam, compression ratios that you are using, the effect
would be from a loss of power at certain RPMs, to a slight gain at a RPM
range where we do not generally run our GMC engines. What works for a fairly
lightweight vehicle with numerically high differential gearing, around 4:10
or so, does not have the same effect on a 12,000 pound vehicle with highway
gearing. In other words, no easy answer.
Jim Hupy
Salem, OR
78 GMC Royale 403

On Sun, Jun 26, 2011 at 7:31 AM, 1104agm <1104agm@gmail.com> wrote:

> What is the affect of grinding the bump put of the exhaust port of the
> heads. Does it reduce the low end torque or what? I have a set of heads
> that these were ground out of. In fact because of a cracked head one of
> these is on the engine now. Well I am assuming cracked head since it leaked
> water and filled a cylinder with water. The head had been milled flat when
> I had a valve job done on it.
>
> Art & Doris
> EL 76
> On Jun 25, 2011, at 10:39 PM, Rob Mueller wrote:
>
> > Larry,
> >
> > If you're talking about the vent I reckon it would be easier to install:
> >
> > http://www.appliedgmc.com/prod.itml/icOid/866
> >
> > Ken Frey installed a 90° air line fitting in Double Trouble. He said
> there
> > was just enough room to get a tap in there and he greased it to hold the
> > sworf. It must have been OK as I've put about 12K miles on since he did
> it.
> >
> >
> > Regards,
> > Rob M.
> > Sydney, Australia
> > AUS '75 Avion-The Blue Streak TZE365V100428
> > USA '75 Avion-Double Trouble TZE365V100426
> >
> >
> > -----Original Message-----
> > From: Larry
> >
> > I have wondered if it would be worth while to wrap the exhaust where the
> > tranny over flow would pour out fluid. Anything to keep from flaming up.
> >
> > my thought
> > --
> > Gatsbys' CRUISER :d
> > 74 GLACIER X, 260
> > 455/APC/4 bagg'r(ver3)
> > Remflex Manifold gaskets
> >
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