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DodgyDan
11-17-2006, 03:54 PM
:smile: :smile: Hi everyone,I have a Subaru Legacy GT twin turbo on a 1994/95,I was just wondering if anyone knows what the spark plug gap should be on these or what gap they run at best.
:smile: :smile:
Cheers Dan
LeeLee D
11-17-2006, 10:39 PM
Haynes is saying 0.039- 0.043 inch
DodgyDan
11-18-2006, 05:13 AM
Cheers LeeLee D, will give it ago.
shazapple
11-18-2006, 12:15 PM
a lot of spark plugs these days come pregapped, and don't like being gapped
DodgyDan
11-18-2006, 01:42 PM
Being a mechanic its always automatic habit for me to check and adjust plug gaps to manufacturers spec.So being my first subaru i didnt gap them and it ran like s*** on boost but fine on tickover,so then i gapped them to what it says in my technical data manual and it ran alot better and was nice when first turbo kicked in but once second turbo kicked in it just blew the spark out and was farting and spluttering like mad,so today i have re-gapped them to what i always gapped my cosworth at and it now runs as sweet as a nut.A bit of a pain cos its not a 5 min job to get plugs out on these,but it seems to be ok now,
Cheers Dan
rougeben83
11-18-2006, 06:12 PM
Being a mechanic its always automatic habit for me to check and adjust plug gaps to manufacturers spec.So being my first subaru i didnt gap them and it ran like s*** on boost but fine on tickover,so then i gapped them to what it says in my technical data manual and it ran alot better and was nice when first turbo kicked in but once second turbo kicked in it just blew the spark out and was farting and spluttering like mad,so today i have re-gapped them to what i always gapped my cosworth at and it now runs as sweet as a nut.A bit of a pain cos its not a 5 min job to get plugs out on these,but it seems to be ok now,
Cheers Dan

+1, It may not be necessary to gap the plugs, but it's good practice to check that they are gapped correctly for your car. One spark plug model can fit a wide variety of engines from across different makes, so each one will have a different set of optimal ranges for the plug gap.