Re: [ihc] RE: Plugging Rob

[bearbvd@xxxxxxxxxxxxxx (Greg Hermann)]

At 8:02 AM 4/22/04, Jim Grammer wrote:
>Hi Rob -
>
>I take it the book was an Autolite application guide? Where IH published
>spark plug info it was invariably Champion IIRC. The late '70's light truck
>operators manuals called out J10YC's, which is an obsolete # AFAIK. Champion
>guides steer you to a J12YC, which according to the Champion heat range
>chart I have is the projected nose equivalent of the J6C. That prolly makes
>Greg's recommended J8C something like a J14YC in projected nose(not on my
>chart, Greg?).

I've never noticed that step in heats between the regular gap and extended
gap champions. Always appeared to me that J8 was the same heat as a J8Y !!

The old time Champion recommended plug for an SV in a Loadstar was J6.

YMMV

Greg
>
>On the Autolite chart, the 85 is 1 step hotter than the 303. Autolite has
>more heat range steps than Champion, so the steps may be closer together.
>Lots of anecdotal reports over the years suggest fewer fouling problems with
>projected nose plugs of either brand. There does seem to be some 'Ford vs.
>Chevy' mentality around plug brand selection, but in general folks seem to
>prefer the Autolites' durability. There has been the occasional report that
>going from an 85 to a 303 cured a ping problem, this goes to Greg's point
>about the effect on apparent timing and overall engine tune. The ping could
>have been cured by changing the timing curve, but the plug swap was an
>expedient. I think I prefer to run projected nose plugs for the variable
>heat range effect and fouling resistance, and tune around them. I still need
>to reduce the overall timing in my Travelall for just this reason. Running
>premium gas does the trick for towing the way it's currently set up, but
>ouch!$$$$
>
>Jim
>
>Date: Tue, 20 Apr 2004 21:14:12 -0700
>From: "Robert  Marks" <scoutmarks@domain.elided>
>Subject: [ihc] spark plugs
>
>Long time lurking, as I have been too busy with work.
>
>Some time ago, discussion about spark plugs said to use the Autolite
>85's and not the 303's.     The 303's were used in the 74 and later 304.
>345. 392's according to the book.  I take it the 303 are a hotter plug
>for emissions reasons?  Any ideas?
>
>
>Rob Marks
>NW Binders