My truck has a cracked 305 engine block and I was wanting to know if I could put one from a 1980 something blazer in it
most likely not, but if you still want to fix it, include your VIN and your zip code and I will try and locate one close to your area and free of charge too.
Many small blocks would bolt up. it's easiest to find the parts listed available local, then go look. when things may or may not match up, theres Hollander interchange you can consult for a list of what fits. You can ask a wrecking yard for advice and buy an engine or research yourself. the libraries have free access to Hollander and auto databases and books about it. if you reuse what makes yours yours, another can accept those parts. You can also buy a complete and the parts to make that fit-in. you say 95, get your vin and be sure then ask around.
The GM dealer can tell you a goodwrench engine price and discuss what you must keep about yours and offer other applications where it can be found. then you go find it to swap. make a deal and know why it will or wont before investing. you see engines and hear claims from sellers, but have to know whats right first. or you end up with problems and stuck with it.
rebuilders can also advise you what to use and talk about what you have, and want it to be when you get it to run. They have many rebuildable cores, we used to give them stacks of them. cannot hurt to ask.
General info from wiki can be looked through for when it was used GM small block 305 usage is what I googled for very close info. No automotive data can be expected perfect unless you find it in an industry manual, these computer sources can be formed by opinion rather than verified facts. It's like sitting in a bar sometimes. everybody knows chevy did not have a 302, that was ford, right ? no, thats the one that blew past you and you never could catch it till the filling station.
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