i have been concidering of going to synthetic on my 91 accord. almost all concerns like leaks and stuff have been ruled out. but i been reading and cars like the ls1 has massive piston slaps. or is it just cars with the V design in the engine? will this be a problem on my 2.2l I4 accord? no matter what synthetic i choose (amsoil, mobil 1) i will be using 10w-30 weight. or should i go higher? driving: high revs city driving alot some freeway 40 miles a day ...hehe one of the many reasons im going to synthetic. car has 166k, very good condition with a purolator filter.