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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

plugs and boost

  • Thread starter Thread starter pthornton
  • Start date Start date Jan 27, 2004

pthornton

Founding Member
Jan 29, 1999
142
0
0
Austin, TX
Jan 27, 2004
#1
  • Jan 27, 2004
  • #1
Autolite
764s / Stock
103s / 1 heat range cooler

I am running the 764s in my car now and under boost I get a little detonation at about 16 degrees timing at peak torque ( ~4500RPM ). I have read where people lose power when going to colder plugs, but I assume this is on the same tune without changes. If I go to the 103s can I bump my timing and how many degrees is the rule of thumb for one step colder plugs?

I use an EEC-tuner and for my street tune I run 15 degrees from 3000 - 4400 and drop to 14 from 4400 to redline. This tune is very safe and never detonates, but I used to run 16 degrees without any problems so I figure my plugs are about ready for a change. Just considering going one step colder.
 
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