Spar Plug Gap
Burning Brakes
Joined: Feb 1999
Posts: 933
Likes: 0
From: Santa Clara Ca
Re: Spar Plug Gap (Bruce B.)
The 55s were designed for a gap around 0.60
TR-6s were designed for a gap around 0.45
Do not gap a plug over _/+ .008 to what the designed for.
55s are for stock, the Tr-6s are one step colder, thus if your stock and
running not to lean, the colder plug is a negative. Use them if you want to run a bit richer.
.For about every 50 HP over stock gain, reduce gap by about 0.10 using a plug designed for that gap.
I use a gap of 38-40 with 475 HP at flywheel.
TR-6s were designed for a gap around 0.45
Do not gap a plug over _/+ .008 to what the designed for.
55s are for stock, the Tr-6s are one step colder, thus if your stock and
running not to lean, the colder plug is a negative. Use them if you want to run a bit richer.
.For about every 50 HP over stock gain, reduce gap by about 0.10 using a plug designed for that gap.
I use a gap of 38-40 with 475 HP at flywheel.
