Ya so im wondering if theres a math formula or a rough estimate.. Where like 100lbs removal equals +15hp or something in that ball park. Reason im askin is cause i got a huge sub box and subs in the back of my s13 and when i took them out today it felt like I gained atleast 20hp.. Dunno though and would love to find out. Subs+box wiegh about 100-125lbs ... so just throw in some reasonable numbers and Ill be able to get in the ball park and decide whether to put them in or sell them.

Thanks