please help

[elitehvac]

I have a 1989 chevrolet silverado with of course no markings or decals.
I have thus far found #'s on the right side behind the head :GM5.7LG SGI and on the left side behind the head I found 14093638 and the motor is TBI fed.how many horse power is this stock and what is the best way to to produce 350-400hp while keeping the stock wiring

[COCACOLA_JUNKY]

I would first remove cats and replace exhaust. 15-30hp.And then i would add a throttle body spacer.15-30hp.i am not 100% for sure but i think u can replace the injectors in the carb too.If u plan on rebuilding the engine i would also put a cam in it, mild to meduim lift.15-20%hp increase.And flat top pistons would be good, make sure u get a good set of rings too,less friction more hp.that should get u close to 350 hp.
But if u want to skip all the little stuff u could add a turbo or super charger there are some good one out there that dont cost alot and are more backyard mechanical friendly and they all have tech support if u need help.
when u remove the exhaust u will need to put in dumby O2 sensors they are available at any performance dist. Air intake is also a good thing to modify,cold air is the key, the more dense the better.
if u have anymore questions please ask,there is alot u can do without changing the wiring harnesses
Del Gerlinsky