Re: [ihc] spark plugs

[bearbvd@xxxxxxxxxxxxxx (Greg Hermann)]

At 12:26 PM 4/21/04, Ryan Moore wrote:
>----- Original Message -----
>From: "Greg Hermann" <bearbvd@domain.elided>
>To: "Robert Marks" <scoutmarks@domain.elided>; <ihc-digest@domain.elided>
>Sent: Tuesday, April 20, 2004 23:36
>Subject: Re: [ihc] spark plugs
>
>
>> At 9:14 PM 4/20/04, Robert  Marks wrote:
>> >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
>>
>> Yep. (for SV's)
>>
>> Champion J8C's. For greater than 15K or so GVW or GCVW, go to J6C's.
>>
>> Greg
>>
>
>Um...  I think "yep" is simplifying way too much.
>
>The 303s are a shallower reach plug than the 85, the 85 has a deeper reach
>and, from what I recall, all previous discussion indicated that some list
>members believed that the 85 is actually the proper interchange for the
>champion with a mistake happening somewhere in the works.
>
>So Greg, when did this come up?  Don't remember seeing this opinion from you
>when this topic came up previously.
>
>-Ryan

The Champions mentioned are a 'standard' reach plug. To get an extended
reach Champion, otherwise equivalent, you would use a "J8YC'.

Generally, an extended reach plug effectively advances the timing, but is
not necessary on an SV to get it to run well. Regardless, the reach of the
plugs is an INTEGRAL part of the tune of an engine. All other things
remaining the same, an extended reach plug will APPEAR to be hotter than a
standard reach plug of the same heat range--because it effectively advances
the timing.

I have seen many instances where an Autolite plug which is SUPPOSEDLY
equivalent to a Champion is, in reality, MUCH hotter !!

Greg