452 head spark plug help

[Phoenix440]

Hi all
Almost ready to start my 440 with reco 452 heads.
I ordered peanut plugs Ngk bpr5fs after reading some info here.
I must have missed the fine print.
The 452s i have appear to have a flat gasket seat even though they have the raised part below plug which I read is to stop people using the wrong type plugs( flat mount type with washer).

My question is what should the plug reach be now that it appears the plug holes are a standard type ( possibly they have been machined)
Does anyone have any recommendations? Would they be the same as a 906 plug now? Will the 3/8 reach plug be too long if the plug ports have been tefaced?
Any help much appreciated.
I have included some pics, hoping someone may know.

 

[pnora]

Heads look to be taper seats to me.

 

[Dave6T4]

My 452 heads use regular plugs. I run Champion RJ14YC with gasket in them.

 

[Jerry Hall]

My understanding is that 452's are the same as 906’s, but with the hardened seats.

 

[Phoenix440]

My 452 heads use regular plugs. I run Champion RJ14YC with gasket in them.

Thanks ill see if if I can track down a set of those.

 

[Phoenix440]

My understanding is that 452's are the same as 906’s, but with the hardened seats.

The plug seats are generally tapered.

 

[ckessel]

My 67 wagon has 452's in it. Tapered seat plug. Autolite 25, AC R45TS etc.

 

[Geoff 2]

Hard to tell for sure from the pic, but looks like a washered plug. Machined area seems too wide for a tapered plug. My NGK catalog, goes to 1974, lists BP5S.

 

[Tony Tee]

you can get them machined.

 

[Phoenix440]

My 67 wagon has 452's in it. Tapered seat plug. Autolite 25, AC R45TS etc.

Thanks, these are flat and need a washer and flat shoulder type plug, which is odd for 452s i believe.

 

[Phoenix440]

View attachment 1962825you can get them machined.

Great photo, that explains it. My concern was the plugs may sit further into the combustion chamber than they should. Sounds like a 906 style plug should work.

 

[Phoenix440]

Hard to tell for sure from the pic, but looks like a washered plug. Machined area seems too wide for a tapered plug. My NGK catalog, goes to 1974, lists BP5S.

Yes looks they have been machined for washer plug, just thinking the plug may sit further into the chamber than standard, which may be an issue. Thinking of trying the champions mentioned by Dave6T4.

 

[493 Mike]

I do not believe a gasketed plug will protrude enough to cause any clearance issue, unless you have GIANT domes on the pistons. So proceed with the above recommendations.
Mike

 

[Dave6T4]

I have never seen a tapered plug 452. The ones I have used are like 906's.

 

[pnora]

Hi all
Almost ready to start my 440 with reco 452 heads.
I ordered peanut plugs Ngk bpr5fs after reading some info here.
I must have missed the fine print.
The 452s i have appear to have a flat gasket seat even though they have the raised part below plug which I read is to stop people using the wrong type plugs( flat mount type with washer).

My question is what should the plug reach be now that it appears the plug holes are a standard type ( possibly they have been machined)
Does anyone have any recommendations? Would they be the same as a 906 plug now? Will the 3/8 reach plug be too long if the plug ports have been tefaced?
Any help much appreciated.
I have included some pics, hoping someone may know.

View attachment 1962795

View attachment 1962796

View attachment 1962797

View attachment 1962798

Must be my eyes and the camera angle. The seat looks tapered to me.

 

[khryslerkid]

Hi all
Almost ready to start my 440 with reco 452 heads.
I ordered peanut plugs Ngk bpr5fs after reading some info here.
I must have missed the fine print.
The 452s i have appear to have a flat gasket seat even though they have the raised part below plug which I read is to stop people using the wrong type plugs( flat mount type with washer).

My question is what should the plug reach be now that it appears the plug holes are a standard type ( possibly they have been machined)
Does anyone have any recommendations? Would they be the same as a 906 plug now? Will the 3/8 reach plug be too long if the plug ports have been tefaced?
Any help much appreciated.
I have included some pics, hoping someone may know.

View attachment 1962795

View attachment 1962796

View attachment 1962797

View attachment 1962798

Plugs with a ring or crush gasket. See the recess...

Motor home head. Taypered plug. Note the bump.

 

[Dave6T4]

So that's the difference; Motorhome versus Passenger car. Chrysler should have given them a different part #.

 

[Tony Tee]

here's the 452 after machining with the plug installed medium tight.

 

[Sixpactogo]

I had a 78 D150 with the factory 440 engine. I'm pretty sure I always ran the Champion RJ12YC plugs.

 

[Tony Tee]

So that's the difference; Motorhome versus Passenger car. Chrysler should have given them a different part #.

Not the only difference, The industrial 452 has two small cooling passages drilled next to the spark plug for more cooling.