spark plug heat range
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From: Westchester, NY
spark plug heat range
I recently bought an 85 944 track (DE) car and while going over it noticed that it had WR7 instead of WR8 (underhood sticker) plugs installed. Do I want to go eith a colder plug for a track car or was this a mistake by the PO? The car is street legal but doesn't get driven much on the street besides going to/from tracks.
Stef
Stef
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Joined: Jun 2001
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From: Camas, WA
"generally" for a track/race application, especially if modified, you'll run one plug cooler.
However, a word of caution ...
Bosch plug# system and NGK plug# system are complete opposites ...
If memory serves me correct:
With Bosch plugs the higher the number the colder the plug and with NGK ... the higher the number the hotter the plug.
(I'd double check this but I think I'm correct)
However, a word of caution ...
Bosch plug# system and NGK plug# system are complete opposites ...
If memory serves me correct:
With Bosch plugs the higher the number the colder the plug and with NGK ... the higher the number the hotter the plug.
(I'd double check this but I think I'm correct)
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Joined: Jan 2002
Posts: 95
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Wrong ( sort of )...
the modern Bosch series using single digits , for example a W7 is warmer than a W5.
However, the "old" bosch system with 3 digits 9 W225, etc), goes in the opposite direction on warmth.
--Wil Ferch
the modern Bosch series using single digits , for example a W7 is warmer than a W5.
However, the "old" bosch system with 3 digits 9 W225, etc), goes in the opposite direction on warmth.
--Wil Ferch
