linelock issues…

Hello everyone, ive got a bit of a problem with my linelock...no matter how hard i pump the brakes before i engauge the linelock i always overpower the front brakes when doing a burnout (in the water box or not), its like they arent even braking. i know the linelocks working fine, i just cant get enough pressure in the fron lines, what could i do to resolve this?
The brake setup is the front are SSBC 'stock' 11" 4 piston brakes and the rears are wilwood 12" 4 pistons (i know..the rears were an afterthought). I have a brake booster and a vaccum canister as well..
In addition to the linelock plumbed to the front, i have a proportioning valve going to the back..Now, should i turn the rear brake pressure down and see if that helps me pump the fronts pressure up? Thanks for your input here..
Author: 68plymouth70