My names david im 21 and have 2 kids just have a pretty good idea bout what im doing here but just need a little advice i have a 1989 chevy s10 blazer 4x4. 4.3L TBI i was wondering if I can swap it with a 94 4.3L and everything match up?

 

The 94 is the last year of the 1st gen Blazer. The engine should pretty much fit like a glove as they have changed nearly nothing in between years. Not sure if the 89 already had a balance shaft. Apart from that I would suggest to grab the whole engine wiring and ECU of the 94 as well. Problems are in the details. Small changes in software, some changes in hardware like routing of vacuum lines etc. Camshaft is an unknown which will IMHO be the critical point if it works "properly" with the 89 ECU or not.

The transmission being the other unknown. Not sure if the 89 already had the 4L60E. The 94 has the electronic version. So it will come down if the engine can run correctly with the 89 ECU or not. A lot of work and money which may turn out to be a nightmare.

Depends on what the situation is. If the 94 is nearly for free and you do not need the Blazer as a daily ride. Maybe an option to go that way.