Whats the difference between the 5/16" spacer and the 1/2" spacer and which one should I buy for my 03 G35 6 - spd sedan ?

 

should have really searched.

5/16" spacer from motordyne is basically the best gains all throughout

1/2" gains are lil more, but i think you lose a lil bottom or soemthing forgot, but i could be totally wrong too about losing anything

i'd get 1/2" though, but 5/16'th most popular

 

Just got a 5/16" Iso Copper, and I love it. Really notice a difference. Love the low end, so glad I didn't get the 1/2"

 

Motordyne hands down and there have been really no shown gains from the 5/16th to the 1/2 inch spacer.