Thread: 305 to 350 parts swaps

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I got a new project, it,s been two years sience I posted here, but you have been the greatest help on on past projects. Thank you all so much. So here is my question, my new project is a 51 chevy pick up, it has a 305, but needs some upgrades mainly a distributor first, if we invest in a msg distributor could it latter work in a 350 wich is going to be the next engine.attually if you gays know what parts are interchangable it would save money, like i noticed the strock is the same, are the jornels the same also? It,s nice to be back here, Thanks

Distributor mounting is the same on all 1st generation small blocks from 265's through 400's

Welcome back, Craig!

Pretty near everything except heads (some have used 305 heads on 350 - but need to check clearances first) and pistons will interchange. Manifolds, water pump cam shaft, timing set. Part number 3932442 is a common large journal (2.45/2.10) cast crank for the 305/350 with two 2 piece seals but remember cranks and rods need to be balanced as a set so don't randomly mix & match the rods.

All the bolt on, i.e., valve covers, alternator, fuel pump, etc.. interchange.

Have Fun,
Glenn

Thank You, so much for your quick responses. You all are the best!

Well I got down to where you typed "attualy if you gays" and went for coffee before I continued reading--------



305 bore size is 3.736------------so about the only things I would swap between them would maybe be the valve covers and maybe the starter/alternator-----

I think what you're asking is if the parts that you might buy for the 305 that's in it today can be used on a 350 that you'll spring for later? Say you're wanting to change out the intake you can spring for the one you'll eventually want for the 350 knowing that it might not be the absolute best choice for a 305, but it'll fit and will offer some level of improved flow, efficiency and performance for your 305. Specific to your question on the distributor, like Ken & Glenn said you can feel secure buying a top quality electronic distributor for the 305, knowing that you'll be able to drop it into the Gen I 350 that you get later. Watch out for counterfeit junk out there in the electronics arena. Buy from a reputable vendor and don't be tempted by the evilBay bargain basement prices on what looks like the real thing.

A note on intake manifolds-----------IIRC there are three different bolt patterns/angles on these engines over the years----you'll be better off waiting til you do the 350 to get 350 parts--------about all you can trust to fit/perform in your installation is the motor mounts and exhaust system------

Jerry, when did they change the bolt pattern on the intake manifold? It was my understanding that all gen 1 sbc's are basically the same externally

There are different angles of the bolts into the heads with the later fuel injected engines---and the later heads are more readily available in some areas - so be careful of what manifold/head combo you buy-----

Being a Ford guy every since being a mule team driver----I was always harped at about the chevys all being the same while the fords were all mixed up on parts, but let me tell you one simple fact----try being in the race engine machining business and you will see very quickly how many different versions of the chevy engines there are-and its not always drivers or passengers side dipstick----------------