i have a 1986 cutlass supreme and am wanting to drop a chevy 400 c.i down in. when i look it up at the parts store i have to say my vehicles a 1973 chevy caprice so will those motor mounts fit in my cutlass or would i have to mod the frame for those mounts



it has 307 mounts right now

 

You won't get much help on this site with dropping a chevy engine in your car. Seeing that GM put a chevy engine in this type of car from the factory a 305. You can use those mounts for your chevy engine.

You could drop a 403 Olds in your Cutlass they are easier to find then a 400 Chevy. The 403 would bolt right up in the place of the 307. The 400 will involve more work to drop in. Wiring is different for one.

 

the only reason why im dropping a chevy 400 in is because my step dad has one in the garage just sitting there waiting to lock up and i cant find a 350 rocket (which i'd love to have) or really any olds motor that people arent charging out the rear for.

 

They're all Rockets, post in parts wanted.

 

I don't believe any Chevrolet engine belongs in an Oldsmobile, but especially not a small-block 400. For that matter I don't think a SB 400 belongs in anything. Grenade waiting to explode if it's pushed hard, especially if it has been bored AT ALL. No matter who built it. The only worse GM-produced V8 engine I can think of would be the 68-69 Oldsmobile 400 ci, and those liked to sling rods thru the block too.


Is your 307 running and driving right now? If it is, wait things out. An Oldsmobile 350/403 engine will surface sooner or later and you might be surprised how cheap.

What's your general location? There may be someone on here close by who can help you find an Olds engine and make sure you don't get a 260 or another 307.

 

Welcome to CO. Hope you can find yourself an Oldsmobile engine as it would be much easier to do. By the time you modify the engine and the car to match the 400 you will have spent the difference (well not really since the 400 is free). It will cost you some money either way.

 

like i said its just sitting around in the garage waiting to lock up the only thing thats been done with it is a 202 cam and i dont think a chevy motor should be in an olds either but since its here just sitting around why blow the money when i can blow the chevy then blow the money lol when i find something im ready to buy they show me up and never show up. im also just using the car as a daily not a street rat or hot rod and im in the dayton ohio area
the 307 runs just fine the only problem is the valve covers there 5 bolt heads and valve covers and the only valve cover/gaskets i can find is 10 bolt and thats why i think my gaskets keep leaking and why i pulled the 307 even though i was going to anyways

even if i drop this 400 right when i find the right deal on an olds motor to put back in that chevy's coming right out

 

so to help me make a decision on not making the chevy swap what all mods can you think of that i will have to do to make this work

 

it also has a 650 holley carb on it so would i have to change the computer still

thanks to everyone helpin me out esp. since im talkin about a chevy motor

 

do you have the transmission plus cross member, drive shaft, wiring harness will need redone power steering pump needs changed around you will need all the Chevy stuff to convert over hoses and such there going to be more in it then just dropping it in there and walking away I'm not far from Dayton olds engines can be found .

 

If it is truly just a convenience thing and the 307 is running why not sell the chevy motor and use the proceeds to buy an Oldsmobile motor and build it on a budget as you earn the money? This will keep you at a reasonable pace that you can afford and you will have the correct engine for the car.

About the ten hole gaskets vs. five hole covers. That will not make them leak. Make sure a previous owner did not depress the area around the holes of the covers. After cleaning the cover place it on a nice flat surface like a kitchen counter top and see where the depressions or divits are. They will need to be flattened out. You can use a piece of wood that is the width of the valve cover lip as an anvil or dolly and then hammer on the gasket side of the depression to flatten it out, use a small hammer with repeated light strokes. Also, have you used any gasket material or adhesive on the gaskets? If you do, you should wait until it sets up before flipping the covers over to install them. If the gasket is mis-aligned at all it may leak. Finally, be sure you are cleaning the gasket surface area on the heads well enough to remove any old gasket material. You can also use spreaders that distribute the pressure of the hold down bolts over a larger area. The can be purchase aftermarket and look like stretched out washers with wings. Good luck.

 

Yes you could sell the Chevy engine or trade it. Chevy guys see the 400 as a holy grail engine. Which I don't understand why. They put high value on it. If a Chevy guy has a Olds engine chances are he would trade you for it. You never know you might be able to get a running 350, 403 or maybe a 455. Put it on cragslist and see what happens.

 

If you really want a Rocket 350 at a reasonable price PM me. I just pulled one from my 72 cutlass that has 13,500 miles on it. It is an Auto Zone or Advance Auto crate motor.

 

As many as I've seen puke their bottom end all over the road, I don't understand it either. Then if they're bored much at all they'll run dangerously hot. At least a 403, which also has siamesed bores, will stand overboring better than the SBC 400.

They like that big-inch small-block idea, but they don't understand it was never designed to be a high-performance engine. It was because Chevy needed cubes to haul fat-*** Caprices/Impalas around and knew some customers would not buy the big-block but then complain about a smogged 350's performance.

Tell 'em ya gotta have a running Olds engine and some boot to get that 400!