GMCforum
For enthusiast of the Classic GMC Motorhome built from 1973 to 1978. A web-based mirror of the GMCnet mailing list.

Home » Public Forums » GMCnet » [GMCnet] 455 spark plugs
[GMCnet] 455 spark plugs [message #350614] Wed, 11 December 2019 11:10 Go to next message
Emery Stora is currently offline  Emery Stora   United States
Messages: 959
Registered: January 2011
Karma: 4
Senior Member
I forgot to say that Dick Paterson recommends always using a torque wrench when installing plugs.
Most of us just spin them in and lean on the wrench.
Dick says to torque them to 26-30 ft-lbs.
Over torque can distort the thin base and fracture the “gas tight” seals between the porcelain and metal base.

Emery Stora
77 Kingsley
Frederick, CO
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
Re: [GMCnet] 455 spark plugs [message #350615 is a reply to message #350614] Wed, 11 December 2019 11:27 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
Also the gap not to exceed .040.
There are books that call for .080, that was changed by GM, but it cannot
be erased, just like the front wheel alignment specs.


On Wed, Dec 11, 2019 at 9:10 AM Emery Stora via Gmclist <
gmclist@list.gmcnet.org> wrote:

> I forgot to say that Dick Paterson recommends always using a torque wrench
> when installing plugs.
> Most of us just spin them in and lean on the wrench.
> Dick says to torque them to 26-30 ft-lbs.
> Over torque can distort the thin base and fracture the “gas tight” seals
> between the porcelain and metal base.
>
> Emery Stora
> 77 Kingsley
> Frederick, CO
> _______________________________________________
> 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@appliedairfilters.com
http://www.appliedgmcrvparts.com
1-800-752-7502
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] 455 spark plugs [message #350616 is a reply to message #350615] Wed, 11 December 2019 13:30 Go to previous messageGo to next message
Jerry Wheeler is currently offline  Jerry Wheeler   United States
Messages: 246
Registered: January 2013
Karma: 2
Senior Member
What did Dick say for an Olds 403 engine??
JR Wheeler 78 Royale 73 Painted Desert


On Wed, Dec 11, 2019 at 12:28 PM Jim Kanomata via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Also the gap not to exceed .040.
> There are books that call for .080, that was changed by GM, but it cannot
> be erased, just like the front wheel alignment specs.
>
>
> On Wed, Dec 11, 2019 at 9:10 AM Emery Stora via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> I forgot to say that Dick Paterson recommends always using a torque
> wrench
>> when installing plugs.
>> Most of us just spin them in and lean on the wrench.
>> Dick says to torque them to 26-30 ft-lbs.
>> Over torque can distort the thin base and fracture the “gas tight” seals
>> between the porcelain and metal base.
>>
>> Emery Stora
>> 77 Kingsley
>> Frederick, CO
>> _______________________________________________
>> 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@appliedairfilters.com
> http://www.appliedgmcrvparts.com
> 1-800-752-7502
> _______________________________________________
> 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
Re: [GMCnet] 455 spark plugs [message #350617 is a reply to message #350616] Wed, 11 December 2019 13:57 Go to previous messageGo to next message
Emery Stora is currently offline  Emery Stora   United States
Messages: 959
Registered: January 2011
Karma: 4
Senior Member
Since I don’t have a 403 I didn’t ask him. It’s likely the same plug but perhaps you should email him and ask.

Emery Stora
77 Kingsley
Frederick CO

> On Dec 11, 2019, at 12:30 PM, Jerry Wheeler via Gmclist wrote:
>
> What did Dick say for an Olds 403 engine??
> JR Wheeler 78 Royale 73 Painted Desert
>
>
> On Wed, Dec 11, 2019 at 12:28 PM Jim Kanomata via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> Also the gap not to exceed .040.
>> There are books that call for .080, that was changed by GM, but it cannot
>> be erased, just like the front wheel alignment specs.
>>
>>
>> On Wed, Dec 11, 2019 at 9:10 AM Emery Stora via Gmclist > gmclist@list.gmcnet.org> wrote:
>>
>>> I forgot to say that Dick Paterson recommends always using a torque
>> wrench
>>> when installing plugs.
>>> Most of us just spin them in and lean on the wrench.
>>> Dick says to torque them to 26-30 ft-lbs.
>>> Over torque can distort the thin base and fracture the “gas tight” seals
>>> between the porcelain and metal base.
>>>
>>> Emery Stora
>>> 77 Kingsley
>>> Frederick, CO
>>> _______________________________________________
>>> 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@appliedairfilters.com
>> http://www.appliedgmcrvparts.com
>> 1-800-752-7502
>> _______________________________________________
>> 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


_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
Re: [GMCnet] 455 spark plugs [message #350618 is a reply to message #350617] Wed, 11 December 2019 14:50 Go to previous messageGo to next message
powwerjon is currently offline  powwerjon   United States
Messages: 849
Registered: March 2013
Karma: -2
Senior Member
Jerry,
I wrote a complete spark plug guide for the 455 and 403 and including Onan
& Gererac generators. I am presently in AZ for the winter and don't have a
copy to current version on my laptop. I had worked with Dick Paterson on
the current plugs that he recommended. If anyone out there has a PDF of
the doc please send it to Jerry or post it. The current version onn GMCMI
does not work and I will be contacting Kim to try and correct it.

J.R. Wright
GMC Great Laker
GMCGL Tech Editor
GMC Eastern States
GMCMHI
TZE Zone Restorations
78 Buskirk Custom 29.5' Stretch
75 Avion (Under going Frame up Restoration)



On Wed, Dec 11, 2019 at 12:58 PM Emery Stora via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Since I don’t have a 403 I didn’t ask him. It’s likely the same plug but
> perhaps you should email him and ask.
>
> Emery Stora
> 77 Kingsley
> Frederick CO
>
>> On Dec 11, 2019, at 12:30 PM, Jerry Wheeler via Gmclist gmclist@list.gmcnet.org> wrote:
>>
>> What did Dick say for an Olds 403 engine??
>> JR Wheeler 78 Royale 73 Painted Desert
>>
>>
>> On Wed, Dec 11, 2019 at 12:28 PM Jim Kanomata via Gmclist > gmclist@list.gmcnet.org> wrote:
>>
>>> Also the gap not to exceed .040.
>>> There are books that call for .080, that was changed by GM, but it
> cannot
>>> be erased, just like the front wheel alignment specs.
>>>
>>>
>>> On Wed, Dec 11, 2019 at 9:10 AM Emery Stora via Gmclist >> gmclist@list.gmcnet.org> wrote:
>>>
>>>> I forgot to say that Dick Paterson recommends always using a torque
>>> wrench
>>>> when installing plugs.
>>>> Most of us just spin them in and lean on the wrench.
>>>> Dick says to torque them to 26-30 ft-lbs.
>>>> Over torque can distort the thin base and fracture the “gas tight”
> seals
>>>> between the porcelain and metal base.
>>>>
>>>> Emery Stora
>>>> 77 Kingsley
>>>> Frederick, CO
>>>> _______________________________________________
>>>> 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@appliedairfilters.com
>>> http://www.appliedgmcrvparts.com
>>> 1-800-752-7502
>>> _______________________________________________
>>> 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
>
>
> _______________________________________________
> 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
Re: [GMCnet] 455 spark plugs [message #350619 is a reply to message #350617] Wed, 11 December 2019 15:04 Go to previous messageGo to next message
Ty Hardiman is currently offline  Ty Hardiman   United States
Messages: 43
Registered: April 2017
Location: Norman, Oklahoma
Karma: 0
Member
The way I see it, there are three factory engine scenarios. A 455 with the points ignition, a 455 with HEI, and a 403 with HEI.

Dick Patterson's position is that they all get the same plug and the same gap. I talked to him about this in October.


Norman, OK / August 1977 Kingsley / 403 / 3.55 / 16" / Quadrajet
Re: [GMCnet] 455 spark plugs [message #350623 is a reply to message #350619] Wed, 11 December 2019 19:52 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
Ty Hardiman wrote on Wed, 11 December 2019 16:04
The way I see it, there are three factory engine scenarios. A 455 with the points ignition, a 455 with HEI, and a 403 with HEI.

Dick Patterson's position is that they all get the same plug and the same gap. I talked to him about this in October.
I have been running NGK XR451X for a very long time. I did not even replace them during the recent overhaul. At Marco, we did a lot of testing for NGK.
At McCord, we made all the gaskets for Champion and A/C for years. The most reliable way to seat the gasket was torque and turn and not torque alone.

Being an ex-engine lab rat, that is why I don't have one of those as listed above.
GM's attempt with HEI was to use the spark energy to reduce misfires that were a big problem in emissions in the early game. If you can do it, it can work in your favor for both emissions and fuel economy. I have done both created my own data and seen the test results. So, I almost redid what we did then that was successful. I say almost because the test engines had an Mallory optical trigger instead of points and it was unreliable even in the test cell. That is why I went with Pertronix as soon as I got the rest of the coach right. I still have it. At first it had a MSD CDI attached to it, but that crashed. So, I dug around in my barn, (those that have been in my barn will believe) and came up with a Mark X CDI by Delta C.1974. It failed the C1 about a year later but I had already procured a Mark XB. It is very similar device with minor improvements. It has been firing those XR451X set at 0.060 for at least 50K mi, and maybe more. (It is cold out where the coach's maintenance log is right now.)

I will put in the warning right now. There are two big issues with this game that you should know about.
First is that the secondary ignition has to be top notch. If it is not, it will not just leak, but common parts may just blow up.
Second is that if you are not a electric shock masochist, stay away while it is running. That level of secondary voltage is out to get you. GOOD!!

The thing I am still missing is how to do an knock controlled spark, but I am working on that. I don't want to have to hammer the air filter housing to fit in the later model distributor.

Matt - The refugee from Dyno-Land


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
Re: [GMCnet] 455 spark plugs [message #350626 is a reply to message #350623] Wed, 11 December 2019 23:01 Go to previous messageGo to next message
Hal StClair   United States
Messages: 971
Registered: March 2013
Location: Rio Rancho NM
Karma: -12
Senior Member
Matt, you reminded me with your talk of some 'electric shock therapy' of a little competition orange Fiat 600 I had in the early 70's. It had the 600 cc motor .040 over with a little head work, a custom Isky stick, headers, Webers and a Vertex magneto that would let you taste the fillings in your mouth when you got too close-and I did a few times I'm afraid. Fun times and memories.
Hal


"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane." 1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM

[Updated on: Wed, 11 December 2019 23:01]

Report message to a moderator

Re: [GMCnet] 455 spark plugs [message #350627 is a reply to message #350626] Wed, 11 December 2019 23:16 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Ah yes, Scintilla/Vertex magneto's. Been there, done that. Got the memories
as a reminder to not get intimately involved with them. They will light
your fire, properly set up. The faster they turn, the more spark they make.
Jim Hupy
Salem, Oregon

On Wed, Dec 11, 2019, 9:04 PM Hal StClair via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Matt, you reminded me with you talk of some 'electric shock therapy' of a
> little competition orange Fiat 600 I had in the early 70's. It had the 600
> cc motor .040 over with a little head work, a custom Isky stick, headers,
> Webers and a Vertex magneto that would let you taste the fillings in your
> mouth when you got too close-and I did a few times I'm afraid. Fun times
> and memories.
> Hal
> --
> 1977 Royale 101348,
>
> 1977 Royale 101586, Diesel powered,
>
> 1975 Eleganza II, 101230,
>
> 1974 Eagle Bus 45',w/slideout,
>
> Rio Rancho, NM
>
> _______________________________________________
> 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

Re: [GMCnet] 455 spark plugs [message #350635 is a reply to message #350618] Thu, 12 December 2019 09:12 Go to previous messageGo to next message
Russell K. is currently offline  Russell K.   United States
Messages: 178
Registered: October 2016
Location: Dunedin, Florida
Karma: 4
Senior Member
http://www.gmcmhphotos.com/photos/data/7181/Spark_Plug_Application_Guide1.pdf

1978 Eleganza II, Dunedin, Florida
Re: [GMCnet] 455 spark plugs [message #350666 is a reply to message #350614] Fri, 13 December 2019 17:19 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
So it should retard the spark when a knock or knocks is/are sensed? does the system need to do anything else such as rich up the mixture, or goose the waste gate a bit?

--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
Re: [GMCnet] 455 spark plugs [message #350669 is a reply to message #350666] Fri, 13 December 2019 20:58 Go to previous message
mghamms is currently offline  mghamms   United States
Messages: 466
Registered: March 2016
Location: Ware, Massachusetts
Karma: 2
Senior Member
ebay has the BOSCH PLATINUM # 4023 for $1.26 each with free shipping.

1977 Kingsley 455 as stock as it gets except lots of Ragusa parts
Previous Topic: [GMCnet] Engine Problem
Next Topic: [GMCnet] Fwd: ROW52 | Toronado has 1 New Results!
Goto Forum:
  


Current Time: Fri Sep 06 11:47:00 CDT 2024

Total time taken to generate the page: 0.00973 seconds