Ka24et turbo gods help!

[shift_haystack]

hey this is my FIRST TURBO build. its a very mild build but i came into some trouble.to make things short and cut to the point i need some help to finish my ka24et. sohc. im in the end process of it and just need help tuning etc. my hp goals are 200-250.

mods are.
t3/t4 turbo
external wastegate
log manifold
2.5 downpipe
stock ecu,injectors,maf
2.5 intercooler piping
12:1 FMU
Walbro 255lph fuel pump
greddy type blov
ebay fmic
egr removed.(not all emissions removed b/c i live in cali)
ngk spark plugs
stanza electric fans


now i need to change my base timing a few degrees. and find out why when i press the brake pedal my engine sounds starved. i have the boost gauge and bov in the brake booster vac line.i idle about 750rpms and my boost gauge reads 20hg.when i press down the pedal it spongy and goes all the way down. it sounds like my engine is about to die and sometimes it does when not warmed up. i also want to know what is the procedure to change base timing on a sohc. i've search and no results. im not experience in tuning and would like to know if anyone can help me out. anyone here local enough with good turbo knowledge please help me out. any other comments on build if constructive is nice too. thanks all. excuse the ugly phone pics.