Who has used NOS Mopar Plug P34P ?

[oldchevelle541]

My owners manual shows 2 plugs for my 69 GTX with stock 440. It calls for J11Y which was the Champion plug and the Mopar plug was P34P which I believe has a slightly longer electrode that extends into the combustion chamber a bit more. Anyone use these on their 440 ? I wish to keep stock.

 

[pnora]

My owners manual shows 2 plugs for my 69 GTX with stock 440. It calls for J11Y which was the Champion plug and the Mopar plug was P34P which I believe has a slightly longer electrode that extends into the combustion chamber a bit more. Anyone use these on their 440 ? I wish to keep stock.

34p is a J11Y.

 

[oldchevelle541]

34p is a J11Y.

I have seen plugs P34P and 34P without the prefix. My manual calls for P34P with the prefix.

 

[pnora]

I have seen plugs P34P and 34P without the prefix. My manual calls for P34P with the prefix.

Same plug. I believe I still have some out in the shop. All they are is champion re-badged for mopar. As I recall some may of had the J-11-Y stamped on the shell.

 

[mmissile]

I have a couple NOS boxes of these.... Gotta find them in my swap-stuff.

 

[Vaanth]

My owners manual shows 2 plugs for my 69 GTX with stock 440. It calls for J11Y which was the Champion plug and the Mopar plug was P34P which I believe has a slightly longer electrode that extends into the combustion chamber a bit more. Anyone use these on their 440 ? I wish to keep stock.

I have seen plugs P34P and 34P without the prefix. My manual calls for P34P with the prefix.

Mopar spark plug, 34P, Chrysler part number 2642913 and later 3420752, is equivalent to Champion J-11Y, and was made by Champion for Chrysler. P-34P is a packaging reference for the 34P spark plug. Early 34P spark plugs were labeled as "34P" and with the part number "2642913". Later spark plugs were labeled as "34P". The Mopar spark plugs were for over the counter replacement. Original production spark plugs were Champion J-11Y.

The following two images show the cover and crossover number page from Champion, specifically for Chrysler, although it is mostly the same as a Champion retail catalog from the same period:

The following image shows a comparison of a Mopar 34P and a Champion J-11Y spark plug:

The following image shows the Mopar P-34P package , and one of its spark plugs marked 34P:

The following image shows three 8-pack packs for 34P spark plugs. On the left is the package before the "P-"was added, the second package has the "P-" prefix,and the third package is a later different style box:

The following image shows the two different package number reference boxes and a spark plug from each:

As shown in post #5, the later 3420752 is in a different 10 pack box. There were also other variations of packaging style and logos, earlier and later that what is shown here, such as the following spark plugs from 1977 with both Champion and Mopar markings on the box:

Chrysler Canada sold parts under the Chryco label instead of Mopar. The Chryco spark plugs were provided by Autolite. The following image shows Chryco spark plugs, number CP22 (Autolite A52):

The following image shows these spark plugs:
Chryco CP22, Mopar 34P (P-34P), Champion J-11Y, Mopar 34PR (P-34PR) resistor

The following image is a marketing shot of a Mopar spark plug diagram:

Mopar 34P and Champion J-11Y are no longer produced. The closest current Champion equivalent is J12YC, or RJ-12YC (resistor).

I have ran both spark plugs. Other than markings and possible porcelain style, there is no manufacturing difference in construction or performance. Heat range and tip projection is the same.

 

[oldchevelle541]

Mopar spark plug, 34P, Chrysler part number 2642913 and later 3420752, is equivalent to Champion J-11Y, and was made by Champion for Chrysler. P-34P is a packaging reference for the 34P spark plug. Early 34P spark plugs were labeled as "34P" and with the part number "2642913". Later spark plugs were labeled as "34P". The Mopar spark plugs were for over the counter replacement. Original production spark plugs were Champion J-11Y.

The following two images show the cover and crossover number page from Champion, specifically for Chrysler, although it is mostly the same as a Champion retail catalog from the same period:
View attachment 1983744
View attachment 1983746

The following image shows a comparison of a Mopar 34P and a Champion J-11Y spark plug:
View attachment 1983743

The following image shows the Mopar P-34P package , and one of its spark plugs marked 34P:
View attachment 1983740

The following image shows three 8-pack packs for 34P spark plugs. On the left is the package before the "P-"was added, the second package has the "P-" prefix,and the third package is a later different style box:
View attachment 1983739

The following image shows the two different package number reference boxes and a spark plug from each:
View attachment 1983738

As shown in post #5, the later 3420752 is in a different 10 pack box. There were also other variations of packaging style and logos, earlier and later that what is shown here.

Chrysler Canada sold parts under the Chryco label instead of Mopar. The Chryco spark plugs were provided by Autolite. The following image shows Chryco spark plugs, number CP22 (Autolite 74):
View attachment 1983742

The following image shows these spark plugs:
Chryco CP22, Mopar 34P (P-34P), Champion J-11Y, Mopar 34PR (P-34PR) resistor
View attachment 1983741

The following image is a marketing shot of a Mopar spark plug diagram:
View attachment 1983745

Mopar 34P and Champion J-11Y are no longer produced. The closest current Champion equivalent is J12YC, or RJ-12YC (resistor).

I have ran both spark plugs. Other than markings and possible porcelain style, there is no manufacturing difference in construction or performance. Heat range and tip projection is the same.

thats a lot of information - thankyou. One can be quickly confused with all of these prefixes. The reason i am looking is becasue I learned recently my GTX received an Autolite plug #85 somewhere in it's life. I have to change that.

 

[oldchevelle541]

Update: found 13 NOS Champion J11Y plugs for a very fair price. Purchased all of them.