Hello everyone I'm NEW to American Muscle and to TGO and would like to say Im proud to finally be a part of the American Tradition and the Third Gen community. I have ZERO experience when it comes to America cars so please bear with me. I have general car knowledge like main components and internals etc. My wife grew in a house full of gearheads so she knows more about V8 than I do at this moment lol. However, I purchased an 85 Camaro with a 305 carb'd V8. After researching the VIN engine code is H reflecting the LG4 5.0L 305 with 4speed Auto tranny without overdrive. The 305 is not running and Father in law looked at it and says the bottom end was bad possibly a spun rod bearing. I've searched for 305 to 350 threads but mostly find tbi and tpi swaps. I'm needing to know if a 305 4bbl to a 350 4bbl is pretty much a straight swap? Or will I be needing all kinds of new parts like intake manifolds, carb, tranny, driveshaft, etc. I first thought that 305 and 350 were pretty much interchangeable but have since found out it is not always the case. Is there a sticky somewhere I don't know about or can someone simplify the whole swap process to give me a general idea as to what I may need other then a carb'd 350 to put in.? Thanks greatly

305 and 350 the same block - so a straight swap. All accessories (alt. a/c, p/s, etc.) as well as intake, carb will swap right over. Only difference might be with heads, older (like pre 1970's) heads won't have accessory bolt holes. Depending on what heads are on the 350, you may want to use the 305 heads if looking for performance - the LG4 heads are usually #416 castings which have alot of potential when ported/polished, and have alot smaller combustion chamber sizes which means more compression. Unless you're looking to build a 400+hp motor, 2 bolt or 4 bolt is fine - if going for super performance get a 4 bolt.

Congrats! And welcome to TGO! Everything you need to know about your new project is here somewhere - the function works great, and we're always happy to help!

Awesome. well here is some news. I found a running OLDS 350 and tranny that was pulled out of a 80's body El Camino. I've seen pictures and looks good just a bit dusty but I'm going to check them out today. oh but carb is not included. Said if I brought one that he would start it up so I could hear it run. Dont know cast numbers or anything yet but will check and report to get opinions. guy is asking 500 bucks. I figured worst case I just end up using the block and slapping my 305 heads on there right? So is worth the purchase?
I wasn't completely sure if there was any difference between and OLDS 350 and Chevy 350. Guy said they were the same.

Make sure it's the chevy 350 and not an olds engine.

You'll also want to make sure that the dipstick is on the right (pass side) of the block or you'll have trouble using it with stock exhaust manifolds. Earlier chevy small blocks have it on the left side and its location interferes with the down pipe for that manifold.

Proper accessory bolt holes in the heads are required, but that's only a problem with much older small blocks. Just make sure the engine you get has the three bolt holes in the heads similar to what you've got.


A chevy 350 will bolt right in and all your stuff will bolt right on. If you go for a later block (one peice rms/roller lifter provision), it will be a better choice but you'll have to swap manifolds (bolt holes are diff) and flywheel.

For the record, the 4th "speed" is the overdrive.

Oh ok. I was just reciting what the VIN ID specified about the engine and tranny via www.camarosource.ca