350ci Engine Swap

[Guest]

Hello.

I am trying to buy a used 350 engine to put into my 86 cutlass supreme. Its a 2 bolt main with pistons, crank, rods, and flywheel. I am currently running a 305 motor in my car. Now this guy says that the heads, valves, intake, etc. from my existing 305 motor will all fit on to the 350 motor as it is. Is that true? I mean if I buy this engine block, can I still use the rest of the engine parts from my 305 motor?

I am looking for a used running 350 motor. If someone has one and wants to get riid of it, please let me know.

Thanks,

Munib

[InMyMerryOLDSMOBILE]

Are you talking about chevy or olds engines? Olds never made a 305, they made a 307. That is the that may have come in your 86.

[Sgt Art]

I pretty sure all standard production Olds engines were two bolt mains. It's said Chevy went to four bolt on some of their engines because the castings are mush. Olds castings are supposed to have greater nickel content and stronger.

It is possible to swap 307 olds heads, intake manifold and other parts (not pistons) with a 350...but why would you want to? Performance will suck. Also, you may have a 305 Chevy engine in your car. If you do, the two engines would have nothing in common. See the thread about engine I.D. and find out which engine you have. If the engine in your car is in fact a 305 Chevy, an easier swap might be a 350 Chevy rather than the Olds. For one thing the starter on a Chevy is on the passenger side, Olds is on the driver side. That's not a big thing to over come, but your accessories may well be. Think about it.

[Guest]

I have a 305 chevy engine. I have confirmed it. 307 distributor was on the radiator side, and my car's distributor is on the firewall side towards the windshield. It is definitely a 305, and the engine number checks out.

Now this 350 that I am buying - will it give me more performance boost? Do I put the 305 heads, valves, camshaft on the 350 motor or do I buy newer stuff?

I also have an Edelbrock performer intake with a 600 CFM Edelbrock carb. Those will fit the 350 as it is. But the main question is - is it worth it to do this and end up doing a rebuild or better to just get a fully running 350 from somewhere?

If somebody knows someone who is selling a used 350 motor and can ship it to Toronto, Canada, I will appreciate it.

best regards,

[Sgt Art]

"I have a 305 chevy engine. I have confirmed it. 307 distributor was on the radiator side, and my car's distributor is on the firewall side towards the windshield. It is definitely a 305, and the engine number checks out."

The 307ci Olds engine has it's distributor in the rear also (all Olds engines do) just like a 305 or any other Chevy engine. You can't go by that alone. The Chevy engine's distributor goes through the intake manifold, the Olds distributor goes into the block behind the intake manifold. Both, however, are by the firewall, neither is mounted in the front of the engine. In GM cars only Buick and Cadillac engines do that. The quickest way for you to know for sure is check which side the starter motor is on. The battery is probably on that side too. Chevy on the passenger side, Olds on the driver side.

Now assuming we're talking Chevy engines here (and it doesn't matter if they are Chevy or Olds) why in the world would you want to put heads from a small CID engine on one that is larger. Both 305 Chev and 307 Olds heads have awful performance when compared to earlier 350 (either maker) heads? To answer your question, yes, you can bolt up the heads and swap other parts. The accessories, p/s pump, water pump, a/c compressor, alternator should all mount up in either case. In 86 or 87, Chevy changed the angle of the cylinder heads and intake manifold mating surfaces, so an older intake will not mate up properly with the newer head design. My advise, is get 350 heads for a 350 engine. The small cid engine heads may not flow worth a hoot.

The Chevy engine and Olds (Buick, Olds, Pontiac aka BOP) use a different bolt pattern mounting for the transmission. Therefore, you can't just drop a 350 Olds in where a 305 Chevy engine was and bolt up to the tranny. Again, if you have a Chevy engine in there, replace it with a Chevy, if it's an Olds, put an Olds in there.

Chevy was selling newly made 1985 and back 350 four bolt main truck engines in the crate for $1250.00 (USD) awhile back. I bought one for my truck, and one for an 87 TransAm (it had a 305 Chev in it). They're long blocks so basically you just take the accessories off your old engine and mount them on the new engine and drop it in. It was a very easy job. You can't hardly build an engine for less than that.

[Grimm]

Sounds to me like you indeed have a Chevy engine. I've read before on other boards that a lot of the Canadian Cutlasses had Chevy engines.

[Guest]

It is not uncomon to find a Chevy motor in an 78-86 Cutlass. He said he had a 305(Chevy)and wanted to buy a 350 that had a 2bolt main (obviously Chevy, since us Olds guys don't talk in terms of 2 or 4 bolt main Olds aint got 4 bolt mains)The only motor offered for the G body Olds that had a distributor in the front was the Buick 231 V6.

This is a fairly simple swap between the Chevy Motors. You will need the block, crank, rods, pistons, cam, and heads from the donor car to make this worth the effort. Everything else from the existing motor will swap right over. I also recomend new lifters, timing chain, and you really should consider a new cam and piston rings, at the very least, if you do not plan on rebuilding the motor.

The only problems you will run into is if the donor car/motor is of the 86 and later 1 piece rear main variety. Then you will need the oil pan and valve covers from the donor and will need to modify the 4 center bolt holes on the intake manifold to complete the swap.