air in air out big problem with tbi.
crappy intake for mass air flow. 4 barrel intake with adaptor plate to tbi easy swap.
vary wimpy stock cam. at .050 its 174/179 and .350/.354 thats it. tiny cam.
vary restrictive exaust system. set of headers or shorty headers for 88-up trucks with tiny little bit of frame rail lip removed on driverside.
fix these 3 and bam much better.
lots of guys swap in stock lt1 350 full roller cams. huge diffrence in power. 205/207 and .447/.449 much much better. and all you have to do is lt1 cam lifters spider and lifter bars. thay drop in the truck tbi engines if true 87-up. then timing chain setup for roller cam and the thrust plate to bolt to the front of the block for the cam. these cam/lifters/lifter bars/spider can be found for around 100 bucks off used sale sections like
www.thirdgen.org lots of guys upgrade and sell the stockers cheep.