Technical Hemi spark plug tube question.

Second question today. I ordered in new Spark plug tubes for my 331 which measure 6" in length (maybe a couple of hundreds longer) from a place on line called Hotrod Hardware. They in turn had their vendor, "Moon" send them up. Kinda thought they would arrive, wrong for my motor and sure enough they did, (they listed only one part number for all (3) of the 331-354-392 motors.) The ones delivered are around 6-5/8ths--(9/16th) inches which I'm positive are for the larger 392 I'd guess. So back they go.
So Hemi guys am I close in my assumption ???

 

Try the "normal" (for today's iron engines) Hemi guys... Hot Heads.
http://www.hothemiheads.com/valve_covers/spark_plug_tubes_stock.html

The page doesn't give a length, I'd give them a call, explain your problem

Mike

 

The Chrysler, Desoto and Dodge all use different length tubes, but the engines in within each division used the same length tubes. The Moon tubes you got are made to use on there valve covers only.

 

I shortened the ones I bought.


Sent from my iPhone using H.A.M.B.

 

All DeSoto tubes & 56-58 Chr. are 6 1/4"51-3 Chr are 6 13/16", All Dodge & 53-55 Chr are 5 29/32.

 

Moon covers take the longer tubes. They are the odd ball cover. The other after market covers all take the stock tubes. 331;354;392 all take the same tubes with stock covers. As mentioned call hot heads.

 

I formed a shortened flange on my stock tubes for my 331 - bored 1/8" over to 354. This allowed good seal on top using stock tube rubber gaskets. 331/354/392 tubes are all the same for stock covers. Custom covers, all bets are off.

Drill a hole the size of the tube in a stick of oak, drill a couple cross holes for bolts, cut a slot thru the hole so the bolts will clamp the tube. Clamp a tube in the jig with about 1/8" sticking up then gently tap the rim 'til it is flat to the jig. Works great.

stock tubes need the big washer and cable covers to squish the rubber seal.


The jig


Result

Those are Toyota boots from junk yard.

 

Tanks to all of you, I appreciate your help.

 

@willys36: Thanks for the illustration. I made a hasty jig last year, now will shamelessly steal your design!

 

My 55 331 tubes are 6-3/16. They are original tubes for stock covers with the rubber seal.