20x8.5 all around need help on tires size also :(

alrite guys, lexus is new to me so some guidance would be helpful :biggthumpup:

i got a 2nd gen gs 300
im currently on megan's lp coils

im currently on 245/35 all around... 
with a wheel size of 20x8.5 all around  an a offset of 40 

the thing is i wanna go lower in the front without scrapping 
the top of the splash guard, or fenders (my FENDERS ARE ROLLED) 
i wanna tuck tires.. 

so 225/35? or 225/30? 
thanks guys :biggthumpup:

225/30/20 if u want to slam properly but add spacers
20 mil at least

[QUOTE=volkgt7;369802]225/30/20 if u want to slam properly but add spacers
20 mil at least[/QUOTE]

bro when u say spacers, wat does it do?
And would i be okay with 245/35 in the rear?
Or go 225/30 all around? Thanks