I really recommend the NGK Iridium plugs, the BKR6EIX. They last much longer, and with an occasional use of FI cleaner such as Techron, car starts easily with them. You don't have to remove the plenum as often to clean/replace them. My LS has had a set of them for many thousands of miles, with no required maintenance because of engine missing or hard starting.
FYI, I bought mine from eBay for ~ $6 each, sans tax/shipping.
1989 Milano, Shankle Sport
1991 164S, stock
1994 164LS (~Q)
1972 Morgan 27
previously owned since 1964:
62 Morris MiniMinor 850, 67 Austin 1275 Cooper S (Downton 3/4 race), 64 Giulia Sprint GT (1st red one made), 72 Fiat 128 Sedan, 75 Alfetta Sedan, 78 Alfetta Sedan, 78 GTV, 81 GTV6, 86 GTV6
Last edited by Del; 12-29-2016 at 07:32 PM.