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Overbore Size [message #328505] Mon, 22 January 2018 14:12 Go to next message
Carl S. is currently offline  Carl S.   United States
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Registered: January 2009
Location: Tucson, AZ.
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Senior Member

Long story, but I have a full reciprocating assembly that I acquired from Steve Ferguson, that HE got from another GMCer who received it as part of a warranty settlement from Mondello. The only problem is that (I believe) it has .060 over pistons and rings. I am looking for opinions on whether or not this much of an overbore is an issue on a 455. If it is even questionable, I will try to work out some kind of a deal on those parts and go with about a .030 overbore.

Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] Overbore Size [message #328506 is a reply to message #328505] Mon, 22 January 2018 14:19 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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.060" is OK on the 455. .030" on the 403. If in doubt, have a sonogram
done on the block. Probably not a bad idea in any event.
Jim Hupy
Salem, Or.

On Jan 22, 2018 12:14 PM, "Carl Stouffer" wrote:

> Long story, but I have a full reciprocating assembly that I acquired from
> Steve Ferguson, that HE got from another GMCer who received it as part of a
> warranty settlement from Mondello. The only problem is that (I believe)
> it has .060 over pistons and rings. I am looking for opinions on whether or
> not this much of an overbore is an issue on a 455. If it is even
> questionable, I will try to work out some kind of a deal on those parts and
> go with
> about a .030 overbore.
> --
> Carl Stouffer
> '75 ex Palm Beach
> Tucson, AZ.
> Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive,
> Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American
> Eagles,
> Solar battery charging. GMCSJ and GMCMI member
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Re: Overbore Size [message #328538 is a reply to message #328505] Tue, 23 January 2018 10:31 Go to previous messageGo to next message
kingd is currently offline  kingd   Canada
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Registered: June 2004
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On a LOT of engines 0.060" is probably over the RECCOMMENDED maximum.
Ken H. knows some engine people that could probably give a very educated opinion.
0.060" might work on a particular block but not on another of the same type/brand, etc.
Core shift.
Ken H's friend might also be willing to tell us about "core shift"


DAVE KING lurker, wannabe Toronto, Ontario, Canada
Re: [GMCnet] Overbore Size [message #328540 is a reply to message #328538] Tue, 23 January 2018 10:52 Go to previous messageGo to next message
powwerjon is currently offline  powwerjon   United States
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Dave,
You are not that far from Dick Paterson up in Coldwater, ONT. You can reach him at 705 325-4554. He is the go to person on the 455 engine and the 403 too.

J.R. Wright
GMC GreatLakerTech Editor
78 Buskirk 30' Stretch
75 Avion Under Reconstruction
Michigan

> On Jan 23, 2018, at 9:31 AM, Dave King wrote:
>
> On a LOT of engines 0.060" is probably over the RECCOMMENDED maximum.
> Ken H. knows some engine people that could probably give a very educated opinion.
> 0.060" might work on a particular block but not on another of the same type/brand, etc.
> Core shift.
> Ken H's friend might also be willing to tell us about "core shift"
> --
> DAVE KING
> lurker, wannabe
> Toronto, Ontario, Canada
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Re: [GMCnet] Overbore Size [message #328541 is a reply to message #328540] Tue, 23 January 2018 11:18 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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It's worth the time to contact people like Dick Patterson as he is familiar with the 455/403

Sent from my iPhone

> On Jan 23, 2018, at 10:52 AM, John Wright wrote:
>
> Dave,
> You are not that far from Dick Paterson up in Coldwater, ONT. You can reach him at 705 325-4554. He is the go to person on the 455 engine and the 403 too.
>
> J.R. Wright
> GMC GreatLakerTech Editor
> 78 Buskirk 30' Stretch
> 75 Avion Under Reconstruction
> Michigan
>
>> On Jan 23, 2018, at 9:31 AM, Dave King wrote:
>>
>> On a LOT of engines 0.060" is probably over the RECCOMMENDED maximum.
>> Ken H. knows some engine people that could probably give a very educated opinion.
>> 0.060" might work on a particular block but not on another of the same type/brand, etc.
>> Core shift.
>> Ken H's friend might also be willing to tell us about "core shift"
>> --
>> DAVE KING
>> lurker, wannabe
>> Toronto, Ontario, Canada
>>
>> _______________________________________________
>> 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:
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Overbore Size [message #328547 is a reply to message #328506] Tue, 23 January 2018 15:58 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Registered: May 2010
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Keep in mind that .060" is only .030" on each side. Less than 1/32". The
455 is an "OLD SCHOOL" engine. SMALL bore, LOOONG stroke. Lots of meat
around the cylinders, and a really good casting with high nickel content.
Not much problem with "core shift" in these engines compared to "modern"
engines like 350 chev. Don't believe me? Ask Dick Paterson.
Jim Hupy

On Jan 23, 2018 9:18 AM, "Jim Kanomata" wrote:

It's worth the time to contact people like Dick Patterson as he is familiar
with the 455/403

Sent from my iPhone

> On Jan 23, 2018, at 10:52 AM, John Wright wrote:
>
> Dave,
> You are not that far from Dick Paterson up in Coldwater, ONT. You can
reach him at 705 325-4554. He is the go to person on the 455 engine and
the 403 too.
>
> J.R. Wright
> GMC GreatLakerTech Editor
> 78 Buskirk 30' Stretch
> 75 Avion Under Reconstruction
> Michigan
>
>> On Jan 23, 2018, at 9:31 AM, Dave King wrote:
>>
>> On a LOT of engines 0.060" is probably over the RECCOMMENDED maximum.
>> Ken H. knows some engine people that could probably give a very educated
opinion.
>> 0.060" might work on a particular block but not on another of the same
type/brand, etc.
>> Core shift.
>> Ken H's friend might also be willing to tell us about "core shift"
>> --
>> DAVE KING
>> lurker, wannabe
>> Toronto, Ontario, Canada
>>
>> _______________________________________________
>> 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

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Re: [GMCnet] Overbore Size [message #328548 is a reply to message #328506] Tue, 23 January 2018 16:18 Go to previous messageGo to next message
BobDunahugh is currently offline  BobDunahugh   United States
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.060 over is somewhat common. The only real down side is that it can't be bored again. In a motorhome. You'll never live long enough to have that as an issue. Bob Dunahugh
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Re: [GMCnet] Overbore Size [message #328549 is a reply to message #328548] Tue, 23 January 2018 16:23 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Bob, there is always sleeves. (Grin)
Jim Hupy

On Jan 23, 2018 2:19 PM, "Bob Dunahugh" wrote:

> .060 over is somewhat common. The only real down side is that it can't be
> bored again. In a motorhome. You'll never live long enough to have that as
> an issue. Bob Dunahugh
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Re: Overbore Size [message #328553 is a reply to message #328505] Tue, 23 January 2018 17:26 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Location: Woodstock, IL
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With the amount of work it takes to R and R an engine in a TZE, I would not want a + .060 in mine when pulling a long long grade over 6%.
I would put a meatier block in the MH and use that one in a Cutlass, 442, or 98 where long term heat loads are much lower.


John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] Overbore Size [message #328556 is a reply to message #328506] Tue, 23 January 2018 18:06 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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John, you are certainly entitled to your opinion. Spend your money however
you see fit.
Jim Hupy

On Jan 23, 2018 3:27 PM, "John R. Lebetski" wrote:

With the amount of work it takes to R and R an engine in a TZE, I would not
want a + .060 in mine when pulling a long long grade over 6%.
I would put a meatier block in the MH and use that one in a Cutlass, 442,
or 98 where long term heat loads are much lower.
--
John Lebetski
Woodstock, IL
77 Eleganza II


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Re: Overbore Size [message #328558 is a reply to message #328505] Tue, 23 January 2018 20:47 Go to previous message
JohnL455 is currently offline  JohnL455   United States
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I have a 10k engine that runs great so hopefully I won't be spending any money on it at all!

John Lebetski
Woodstock, IL
77 Eleganza II
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