What do I need to do. 90 5.7 to old school 350.

[408Lbb]

the older style heads have different intake bolt hole angles, but u can slot ur tbi intake holes to make it work, it should b the 4 center bolt holes, 2 on each side,put all sensors and stuff off tbi motor on the older motor, also u have use the older style flywheel, as the tbi style has a wheight on it and wheel throw of the balance of motor, if u use the 88 up flywheel it will beat the babbit outa ur mains and rod bearings,so use oler style, i think thats it

[singlecab1500]

yea i forgot all about intake bolt hole angle but i thought the intake angle was only different if it was a 4 bolt main or a 2 bolt main

[singlecab1500]

oh yea and what year is the old school 350 you have laying around that will be the main factor in everything

[1994silverado]

the easiest is to just get a aluminum adapter plate from summit to bolt the throttle body to the carb intake. but make sure its aluminum the steel ones warp if you snug up the throttle body bolts. swap over all the sensors and distributer and drop it in.