Home » Public Forums » GMCnet » [GMCnet] Interested in avoiding bebuilding your 403/455
| [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350574] |
Mon, 09 December 2019 00:44  |
BobDunahugh
Messages: 2465
Registered: October 2010
Location: Cedar Rapids, IA
Karma: 11
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Sorry. I had to speak out on this one. The plastic teeth on the cam sprocket is a grenade that WILL go off. The engine will run perfectly till the bang. GM never considered back then. That people would still be driving these GMC's 45 years later.
Some say that you need to look for signs of true mileage. The condition of the brake peddle is a good one for cars. They stop a lot. We stop very seldom per miles driven. I've seen the brake peddle in a 300,000 mile GMC that looked new. Look at the condition of the suspention. Here again. Some get maintained. Some don't. At this point. It's not the miles driven. It's TIME.
It's simple. Plastic gets more brittle with age. Here's how that sprocket will come apart. Once the plastic breakdown starts. The first shavings start to plug the oil filter. As that plugging of the filter media progresses. The oil filter by pass valve. Starts to by pass more, and more contaminated oil. This is the start of when the main/rod bearings start to be destroyed.
Some say. If it's working fine. Drive it. Or. Not brook. Don't fix it. There's value in that thought. But in this case. I think that putting a good running engine at risk. Has no value. Owners choice. Not my Monkeys. Not my circus.
We've had a GMC since 2003. 42 states, and some of Canada. ( A lot of that first 78 Royale is under this second 78 Royale. ) We've never been stranded to the side of the road. Then towed. ( The fire in 2015. We never got the fire recall.) So can't blame the GMC there.
These 45 year old GMC's can be extremely dependable. There are just a few thing that need to be done to accomplish this. An no money to do it. So. Sorry for butting in. I need to go back under my rock.
Happy trails to all.
Bob Dunahugh
78 Royale
4 COPO Yenkos
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350576 is a reply to message #350574] |
Mon, 09 December 2019 07:01  |
LNelson
Messages: 335
Registered: December 2008
Location: Springfield, MO
Karma: 0
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Bob, before you disappear beneath your rock, your comments remind me of helping my Dad replace the cam gear on my straight 6, 1950 Chevy "go to school" car in a cold shop in Omaha (wood stove). My Dad (just turned 93 a few days ago) called that gear a "fiber" gear. After reading your post, I called him to see if he remembered doing that. Sometimes you have to "tease" the memory of an old loved one.
Anyway, he did remember doing it (fixing the timing gear). My question is: would routine oil analysis show the result of the disintegration of Olds cam gear? I mean, would the destruction of that gear grind up particles heading thru the oil filter that would show up in analysis. Your comments are going to cause me to open up my oil filters with my cutter just like I do for my plane engines.
Always enjoy your insights.
Larry
Larry Nelson Springfield, MO
Ex GMC'er, then GM Busnut
now '77 Eleganza ARS WB0JOT
[Updated on: Mon, 09 December 2019 08:43] Report message to a moderator |
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350577 is a reply to message #350576] |
Mon, 09 December 2019 09:02 |
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Matt Colie
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
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LNelson wrote on Mon, 09 December 2019 08:01Bob, before you disappear beneath your rock, your comments remind me of helping my Dad replace the cam gear on my straight 6, 1950 Chevy "go to school" car in a cold shop in Omaha (wood stove). My Dad (just turned 93 a few days ago) called that gear a "fiber" gear. After reading your post, I called him to see if he remembered doing that. Sometimes you have to "tease" the memory of an old loved one.
Anyway, he did remember doing it (fixing the timing gear). My question is: would routine oil analysis show the result of the disintegration of Olds cam gear? I mean, would the destruction of that gear grind up particles heading thru the oil filter that would show up in analysis. Your comments are going to cause me to open up my oil filters with my cutter just like I do for my plane engines.
Always enjoy your insights.
Larry
Larry,
Glad you still have your dad to talk to....
My experience with disintegrating timing gears in not very extensive, but my next big question would be if the 455 is an "interference" valve gear question. If some engines come out of time, they bend valves. When this happens, there is a lot more work to do than just changing out a timing set.
What I can definitively add is that an oil analysis will probably not predict a nylon timing gear failure. Most lubricating oil analysis looks at what is essentially in "solution" in the oil. If it is chunks, it won't go into the analysis set. Now, cutting open an oil filter may see the chunks, but that has the problem of the running time between chunks and crunch is not very long.
I usually firmly prescribe to the "If it isn't broken, Don't fix it" standard, but this may not be one of those times.
This is one of those times when I would go with the community rule: If you can't prove this has been done - Do it. The failure is too predictable at this time. It should be pretty easy to look at the timing gear cover and determine if it has ever been removed.
Matt
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350579 is a reply to message #350577] |
Mon, 09 December 2019 09:09 |
LNelson
Messages: 335
Registered: December 2008
Location: Springfield, MO
Karma: 0
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Matt Colie wrote on Mon, 09 December 2019 09:02LNelson wrote on Mon, 09 December 2019 08:01Bob, before you disappear beneath your rock, your comments remind me of helping my Dad replace the cam gear on my straight 6, 1950 Chevy "go to school" car in a cold shop in Omaha (wood stove). My Dad (just turned 93 a few days ago) called that gear a "fiber" gear. After reading your post, I called him to see if he remembered doing that. Sometimes you have to "tease" the memory of an old loved one.
Anyway, he did remember doing it (fixing the timing gear). My question is: would routine oil analysis show the result of the disintegration of Olds cam gear? I mean, would the destruction of that gear grind up particles heading thru the oil filter that would show up in analysis. Your comments are going to cause me to open up my oil filters with my cutter just like I do for my plane engines.
Always enjoy your insights.
Larry
Larry,
Glad you still have your dad to talk to....
My experience with disintegrating timing gears in not very extensive, but my next big question would be if the 455 is an "interference" valve gear question. If some engines come out of time, they bend valves. When this happens, there is a lot more work to do than just changing out a timing set.
What I can definitively add is that an oil analysis will probably not predict a nylon timing gear failure. Most lubricating oil analysis looks at what is essentially in "solution" in the oil. If it is chunks, it won't go into the analysis set. Now, cutting open an oil filter may see the chunks, but that has the problem of the running time between chunks and crunch is not very long.
I usually firmly prescribe to the "If it isn't broken, Don't fix it" standard, but this may not be one of those times.
This is one of those times when I would go with the community rule: If you can't prove this has been done - Do it. The failure is too predictable at this time. It should be pretty easy to look at the timing gear cover and determine if it has ever been removed.
Matt
Matt, I assume this isn't a project to perform in a campground somewhere. The hardest part probably is just getting the radiator out, and other elements in the way. Assume it can be done with the engine in the coach.
Larry Nelson Springfield, MO
Ex GMC'er, then GM Busnut
now '77 Eleganza ARS WB0JOT
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350580 is a reply to message #350577] |
Mon, 09 December 2019 09:30 |
Marsh Wilkes
Messages: 155
Registered: January 2004
Karma: -3
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Joe Mondello told me the 455 is an interference engine, I was a little
surprised, but that's what he said.
Marsh (rarely post) Wilkes
-----Original Message-----
From: Matt Colie via Gmclist
Sent: Monday, December 09, 2019 10:02 AM
To: gmclist@list.gmcnet.org
Cc: Matt Colie
Subject: Re: [GMCnet] Interested in avoiding bebuilding your 403/455
LNelson wrote on Mon, 09 December 2019 08:01
> Bob, before you disappear beneath your rock, your comments remind me of
> helping my Dad replace the cam gear on my straight 6, 1950 Chevy "go to
> school" car in a cold shop in Omaha (wood stove). My Dad (just turned 93 a
> few days ago) called that gear a "fiber" gear. After reading your post, I
> called him to see if he remembered doing that. Sometimes you have to
> "tease" the memory of an old loved one.
>
> Anyway, he did remember doing it (fixing the timing gear). My question is:
> would routine oil analysis show the result of the disintegration of
> Olds cam gear? I mean, would the destruction of that gear grind up
> particles heading thru the oil filter that would show up in analysis. Your
> comments are going to cause me to open up my oil filters with my cutter
> just like I do for my plane engines.
>
> Always enjoy your insights.
>
> Larry
Larry,
Glad you still have your dad to talk to....
My experience with disintegrating timing gears in not very extensive, but my
next big question would be if the 455 is an "interference" valve gear
question. If some engines come out of time, they bend valves. When this
happens, there is a lot more work to do than just changing out a timing set.
What I can definitively add is that an oil analysis will probably not
predict a nylon timing gear failure. Most lubricating oil analysis looks at
what is essentially in "solution" in the oil. If it is chunks, it won't go
into the analysis set. Now, cutting open an oil filter may see the
chunks, but that has the problem of the running time between chunks and
crunch is not very long.
I usually firmly prescribe to the "If it isn't broken, Don't fix it"
standard, but this may not be one of those times.
This is one of those times when I would go with the community rule: If you
can't prove this has been done - Do it. The failure is too predictable at
this time. It should be pretty easy to look at the timing gear cover and
determine if it has ever been removed.
Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350581 is a reply to message #350580] |
Mon, 09 December 2019 09:50 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
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Senior Member |
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All engines are interference engines. If the cam stops or skips and the
crank, pistons, and rods don't, they soon will, and abruptly so. I have
broken and bent parts to prove it.
Any "floaters" in the oil is a really, really bad thing. Do not
procrastinate. Fix it before it costs you a whole bunch of that stuff that
is near and dear to your wallet. Jus' sayin'!
Jim Hupy
Salem, Oregon
On Mon, Dec 9, 2019, 7:31 AM Marsh Wilkes via Gmclist <
gmclist@list.gmcnet.org> wrote:
> Joe Mondello told me the 455 is an interference engine, I was a little
> surprised, but that's what he said.
>
> Marsh (rarely post) Wilkes
>
>
>
>
> -----Original Message-----
> From: Matt Colie via Gmclist
> Sent: Monday, December 09, 2019 10:02 AM
> To: gmclist@list.gmcnet.org
> Cc: Matt Colie
> Subject: Re: [GMCnet] Interested in avoiding bebuilding your 403/455
>
> LNelson wrote on Mon, 09 December 2019 08:01
>> Bob, before you disappear beneath your rock, your comments remind me of
>> helping my Dad replace the cam gear on my straight 6, 1950 Chevy "go to
>> school" car in a cold shop in Omaha (wood stove). My Dad (just turned 93
> a
>> few days ago) called that gear a "fiber" gear. After reading your post, I
>> called him to see if he remembered doing that. Sometimes you have to
>> "tease" the memory of an old loved one.
>>
>> Anyway, he did remember doing it (fixing the timing gear). My question
> is:
>> would routine oil analysis show the result of the disintegration of
>> Olds cam gear? I mean, would the destruction of that gear grind up
>> particles heading thru the oil filter that would show up in analysis.
> Your
>> comments are going to cause me to open up my oil filters with my cutter
>> just like I do for my plane engines.
>>
>> Always enjoy your insights.
>>
>> Larry
>
> Larry,
>
> Glad you still have your dad to talk to....
>
> My experience with disintegrating timing gears in not very extensive, but
> my
> next big question would be if the 455 is an "interference" valve gear
> question. If some engines come out of time, they bend valves. When this
> happens, there is a lot more work to do than just changing out a timing
> set.
>
>
> What I can definitively add is that an oil analysis will probably not
> predict a nylon timing gear failure. Most lubricating oil analysis looks
> at
> what is essentially in "solution" in the oil. If it is chunks, it won't
> go
> into the analysis set. Now, cutting open an oil filter may see the
> chunks, but that has the problem of the running time between chunks and
> crunch is not very long.
>
> I usually firmly prescribe to the "If it isn't broken, Don't fix it"
> standard, but this may not be one of those times.
>
> This is one of those times when I would go with the community rule: If you
> can't prove this has been done - Do it. The failure is too predictable at
> this time. It should be pretty easy to look at the timing gear cover and
> determine if it has ever been removed.
>
> Matt
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan
> OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
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>
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350583 is a reply to message #350582] |
Mon, 09 December 2019 10:23 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
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I used to be a co-owner of an automotive machine shop. We worked
exclusively on D.I.N. (European metric) system products, with a smattering
of I.S.O. (Asian) products thrown in. That included an occasional Subaru.
I have seen the results of catastrophic engine failure in them. Pistons and
valves will not co-exist in the same space. Call it what you wish.
Jim Hupy
Salem, Oregon
On Mon, Dec 9, 2019, 8:06 AM Tom Newell via Gmclist
wrote:
> "All" engines are most definitely not interference engines.
>
> Of course, zero flathead engines are interference.
>
> My Subaru 2.2 is famously noninterference, contributing to its properly
> earned reputation for anvil-like reliability. Just run the thing till the
> timing belt breaks... (not the best idea, of course).
>
> Regards,
>
> Tom Newell
> --
> Proud Citizen of
> Los Angeles, California
> Founded 1781 as
> El Pueblo de la Reyna de los Angeles, Alta California
>
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350584 is a reply to message #350574] |
Mon, 09 December 2019 10:41 |
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Tom Newell
Messages: 25
Registered: August 2017
Location: Los Angeles, California
Karma: 0
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So, how is it those valves and pistons are occupying the same space, ever, on a flathead.
We are all wrong sometimes; it does not diminish our value as humans; it in fact proves our humanness. And humanness is a beautiful thing.
Regards,
Tom "owner of a noninterference Subaru 2.2, will never bend the valves or hole the pistons, because, you know, physics, apologies to Richard Denney" Newell
Proud Citizen of
Los Angeles, California
Founded 1781 as
El Pueblo de la Reyna de los Angeles,
Alta California
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350585 is a reply to message #350584] |
Mon, 09 December 2019 11:05 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
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I cut my milk teeth on flathead ford and mercury engines. The valves never
occupy the same space at the same time as the pistons do!
Until they do. And the results are catastrophic nearly every time.
How? Many people are unaware that the valve head is made of different
steels than the stems are. The stem materials are for anti wear and
longevity, the valve heads are heat and pounding resistant. The 2 pieces
are friction welded in a machine similar to a lathe that presses both parts
together at vastly different rates of speed. The resulting friction welds
and fuses both pieces together. These welds can and do fail. The valve head
is then free to occupy any space it chooses. If that is the piston top and
cylinder head, you can visualize the outcome.
I sometimes communicate in abrupt or flippant ways, but seldom with
ridicule or disrespectful intent. Your experiences in life have led you
down a different path than mine have. Doesn't mean that either of us are
right or wrong. Our outlooks are just different. I welcome the differences
and look forward to the discussions.
Jim Hupy
Salem, Oregon
On Mon, Dec 9, 2019, 8:42 AM Tom Newell via Gmclist
wrote:
> So, how is it those valves and pistons are occupying the same space, ever,
> on a flathead.
>
> We are all wrong sometimes; it does not diminish our value as humans; it
> in fact proves our humanness. And humanness is a beautiful thing.
>
> Regards,
>
> Tom "owner of a noninterference Subaru 2.2, will never bend the valves or
> hole the pistons, because, you know, physics, apologies to Richard Denney"
> Newell
>
>
> --
> Proud Citizen of
> Los Angeles, California
> Founded 1781 as
> El Pueblo de la Reyna de los Angeles, Alta California
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350586 is a reply to message #350582] |
Mon, 09 December 2019 11:16 |
Emery Stora
Messages: 959
Registered: January 2011
Karma: 4
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Senior Member |
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The classic definition of a interference engine is:
An interference engine is a type of 4-stroke internal combustion piston engine in which one or more valves in the fully open position extends into any area through which the piston may travel. By contrast, in a non-interference engine, the piston does not travel into any area into which the valves open.
However, as James Hupy indicates even a non-interference engine can become an interference engine if a part such as a valve head breaks. That happened to me about three years when the valve head of my #7 exhaust valve broke loose and punched a hole into the top of my piston.
However, if a cam gear should break it should not cause a problem with interference in a 455 engine.
Emery Stora
77 Kingsley
Frederick, CO
> On Dec 9, 2019, at 9:06 AM, Tom Newell via Gmclist wrote:
>
> "All" engines are most definitely not interference engines.
>
> Of course, zero flathead engines are interference.
>
> My Subaru 2.2 is famously noninterference, contributing to its properly earned reputation for anvil-like reliability. Just run the thing till the
> timing belt breaks... (not the best idea, of course).
>
> Regards,
>
> Tom Newell
> --
> Proud Citizen of
> Los Angeles, California
> Founded 1781 as
> El Pueblo de la Reyna de los Angeles, Alta California
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350588 is a reply to message #350587] |
Mon, 09 December 2019 12:19 |
BobDunahugh
Messages: 2465
Registered: October 2010
Location: Cedar Rapids, IA
Karma: 11
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Senior Member |
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When you put high compression, domed pistons in. Then Joe M is correct. We don't have those pistons in our GMC. And we can use any gas that will burn. I have the Howell/GM EFI, EBL. You can whip the inside of my tail pipe with a tissue. And not stain it. Love my 403. Even when my GVW is at 24,000 LBS .
As to the task at hand. The Radiator DOES NOT have to be removed. As to other engines interference.. Not relevant here.
________________________________
From: Bob Dunahugh
Sent: Monday, December 9, 2019 11:52 AM
To: gmclist@list.gmcnet.org
Subject: Fw: Interested in avoiding bebuilding your 403/455
Thanks Larry for your comment on my past postings. I tried to generally direct them to new owner. And I put my Tid Bit post out when post got all tied up on one topic. Or got boring. The devils in the details. Those are the ones that come up on the road. And put your GMC on a hook back home. There are things that I do at every fuel stop. Take less then two mins to do while the fueling is taking place. Thus don't slow you down at all.
American engines back then. Where built to not have valve interferance issues. As to that Chevy 6. Those back then had a pressed fiber gear on the cam. We have a sprocket with a chain. If you decide to pull that plastic sprocket out. There is a bouble roller chain. Those are a must for engines that have very agressive cam lobes. High valve spring pressures. And run above 6000 RPMs. We don't. So there's no reason to spend twice the money. As to taking the oil filter apart to inspect. Neet idea. But if you find anything in the filter. It's really too late. The damage to the bearings has already started. I agree wth Matt on the testing the oil. But. Then again. To late. It just comes down too. If in dought. Pull it. Want to talk about this. Cell. 319-521-4891 Iowa. Not the end of the earth. But can see it from here.
As to the Harrison air bags. $25 each.
Bob Dunahugh
78 Royale
4 COPO Yenkos
________________________________
From: Bob Dunahugh
Sent: Monday, December 9, 2019 12:44 AM
To: gmclist@list.gmcnet.org
Subject: Interested in avoiding bebuilding your 403/455
Sorry. I had to speak out on this one. The plastic teeth on the cam sprocket is a grenade that WILL go off. The engine will run perfectly till the bang. GM never considered back then. That people would still be driving these GMC's 45 years later.
Some say that you need to look for signs of true mileage. The condition of the brake peddle is a good one for cars. They stop a lot. We stop very seldom per miles driven. I've seen the brake peddle in a 300,000 mile GMC that looked new. Look at the condition of the suspention. Here again. Some get maintained. Some don't. At this point. It's not the miles driven. It's TIME.
It's simple. Plastic gets more brittle with age. Here's how that sprocket will come apart. Once the plastic breakdown starts. The first shavings start to plug the oil filter. As that plugging of the filter media progresses. The oil filter by pass valve. Starts to by pass more, and more contaminated oil. This is the start of when the main/rod bearings start to be destroyed.
Some say. If it's working fine. Drive it. Or. Not brook. Don't fix it. There's value in that thought. But in this case. I think that putting a good running engine at risk. Has no value. Owners choice. Not my Monkeys. Not my circus.
We've had a GMC since 2003. 42 states, and some of Canada. ( A lot of that first 78 Royale is under this second 78 Royale. ) We've never been stranded to the side of the road. Then towed. ( The fire in 2015. We never got the fire recall.) So can't blame the GMC there.
These 45 year old GMC's can be extremely dependable. There are just a few thing that need to be done to accomplish this. An no money to do it. So. Sorry for butting in. I need to go back under my rock.
Happy trails to all.
Bob Dunahugh
78 Royale
4 COPO Yenkos
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350590 is a reply to message #350588] |
Mon, 09 December 2019 17:28 |
Wayne
Messages: 106
Registered: August 2004
Karma: 0
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Senior Member |
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Hi everyone,
The previous owner had a rebuilt 403 short block and heads installed in 1990 @ 98000 miles. I now have 130000 miles. I know I am ok on miles
but that was almost 30 years ago.
Does anyone remember what the common practice of most rebuilders was back then.
Wayne Lawrence
76 Birchaven
Bellflower CA
w.lawrence@verizon.net
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350594 is a reply to message #350574] |
Mon, 09 December 2019 18:47 |
lqqkatjon
Messages: 2324
Registered: October 2010
Location: St. Cloud, MN
Karma: 5
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Senior Member |
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Many engines blow up for a multitude of reasons. Mine was a broken#6 exhaust valve. That was after I thought I did everything right, including a timing chain.
I have seen plenty of non-interfearance engines shot after a timing belt or chain breaks. Some have no issues. It is not always a valve hitting a piston. Spark the hole at the wrong time can do some damage.
Timing gear job is a pain, but not the worst thing to do. Easily done over a weekend. Radiator can stay in. The biggest hassle is dealing with the powersteering bracketry and lifting the engine a little to get the front mount off.
Jon Roche
75 palm beach
EBL EFI, manny headers, Micro Level, rebuilt most of coach now.
St. Cloud, MN
http://lqqkatjon.blogspot.com/
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350595 is a reply to message #350590] |
Mon, 09 December 2019 18:54 |
Melbo
Messages: 144
Registered: August 2018
Location: Albuquerque NM
Karma: 0
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Senior Member |
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Wayne
You can look through the opening where the fuel pump goes. That is how I found my nylon (?plastic?) teeth on the cam gear. I will definitely be replacing the cam gear before I drive this. I will check the compression before I do that so I know if there is more or less work to be done. I am on the fence as to whether or not to start it up and listen for engine noises before I do the timing chain and gears. If the compression check is kind of close on the cylinders I will feel good about not having to get deeper into it. Just my way. Any suggestions are always appreciated.
Melbo
Albuquerque NM Bus Conversion 1978 MCI 1973 GMC
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| Re: [GMCnet] Interested in avoiding bebuilding your 403/455 [message #350598 is a reply to message #350574] |
Mon, 09 December 2019 20:11 |
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pjburt
Messages: 436
Registered: February 2016
Location: Fresno, California
Karma: 1
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Senior Member |
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Something else you might want to consider doing, if it has not already been done. Pulling the intake manifold and blocking the exhaust crossover.
Jerry Burt Fresno, CA.
73 Gmc 26' Canyon Lands
Members: FMCA - GMCMI - GMCWS
A truly happy person is one who can enjoy the scenery on a detour.
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