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Source for a small block olds motor

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I am going to build a 70 Olds Rally 350 for a friend of mine. But I am in need of an Oldsmobile small block 350 motor. Anyone know of a kit or aftermarket that has one. Thanks

Tim

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Posted (edited) · Report post

1970 AMT Olds kit is what comes to mind...Sorry it has a big block....

Edited by slusher

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Posted · Report post

Of all the GM 350-cubic-inch (5.7 L) engines, the Buick 350 has the longest stroke. It made the Buick 350 significantly wider than the other GM 350's — essentially the same width as the Buick big-blocks, which have the shortest stroke of the GM big-blocks. In fact, at a glance the Buick 350 is commonly mistaken for the 455 engine due to the oversized intake manifold atop the engine and conventional angled valve covers like a 400/430/455. The Buick 350 also shares an integrated aluminum timing cover as do most of the Buick small and big blocks which incorporates the oil pump mechanisms as well, leaving the oil filter exposed to oncoming air for added cooling.

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Posted · Report post

You might be able to dummy it up with the 400 out of the AMT 1966 4-4-2 or Lindberg 1967 4-4-2. They big/small Olds are very close in size, and as I'm thinking of it, I think the 400 in those cars may have actually been the small-block.

Those are the only ones I can think of that might work.

Charlie Larkin

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Posted · Report post

Everything that I've heard / seen in reference to the Oldsmobile V8's is that it's the same block , with sizes running frpm 260 V6 up to a 455 .

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Posted · Report post

It's the same basic design block whether it's a 350 or a 400 or a 455.For model purposes just paint the engine the correct color and it'll suffice.

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Posted · Report post

It's the same basic design block whether it's a 350 or a 400 or a 455.For model purposes just paint the engine the correct color and it'll suffice.

Correct. However, you do need to make sure all your accessories ( AC, PS pump, alternator) are located correctly for the specific application, and that you get the right air filter (unless you go aftermarket).

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Posted · Report post

Everything that I've heard / seen in reference to the Oldsmobile V8's is that it's the same block , with sizes running frpm 260 V6 up to a 455 .

Almost. The larger-displacement engines have a slightly higher deck height to accommodate the longer stroke. That's why if you look at the intakes, they're slightly different.

Charlie larkin

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Posted · Report post

Almost. The larger-displacement engines have a slightly higher deck height to accommodate the longer stroke. That's why if you look at the intakes, they're slightly different.

Charlie larkin

Thanks ; I wasn't aware of any deck-height changes within that engine family . Pontiac was similar if I'm not mistaken ...

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Posted · Report post

that's the way I've always heard it; big blocks and small blocks except Chevies looked pretty much the same. it made for some deceptive sleepers "back in the day" when a Skylark badged for a 350 was toting a 455......

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Posted · Report post

Only GM engine that used the same block was pontiac. both the Buick and Oldsmobile used a different block for the 350 and the 455. Being this car is going to be given to my best friend who is a not only a 1970 Oldsmobile Rally 350 owner but an Olds enthusiast and the son of a retired oldsmobile executive and will know the difference.

I may look at the 400 in the 69 442 kit but don't know if it was based on the Hurst/Olds or the 442 as the H/O had a 455. ( retro fitted by Hurst)

Tim

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Posted · Report post

Only GM engine that used the same block was pontiac. both the Buick and Oldsmobile used a different block for the 350 and the 455. Being this car is going to be given to my best friend who is a not only a 1970 Oldsmobile Rally 350 owner but an Olds enthusiast and the son of a retired oldsmobile executive and will know the difference.

I may look at the 400 in the 69 442 kit but don't know if it was based on the Hurst/Olds or the 442 as the H/O had a 455. ( retro fitted by Hurst)

Tim

The engines LOOK virtually identical (very very similar, anyway), as noted above. Again, as already stated, the ONLY reason for different blocks is that the "deck height" is higher on the "big-blocks" to accommodate a longer stroke. Visually, the blocks LOOK the same otherwise (though the "big-block" will be SLIGHTLY taller and wider due to the higher deck. This will also make the assembled engine taller and wider as well). Without measuring the deck-height (or the width across the heads) of a model engine in 1/25 scale, it's about impossible to say whether one is a big-or-small block.

If you want to be absolutely correct, look up the difference in deck-heights between the two, divide the dimension by 25, and add styrene shims to the top of the block (or remove that amount from a big-block to get a small-block) at the head-mating surfaces. This will space the heads farther away from each other, obviously, so the intake manifold will need to be suitably modified...as Charlie has already mentioned.

Here's a very knowledgeable article about identifying one or the other. As you'll see, the differences are all internal other than some numbers and the height / width of the thing.

http://quincyolds455.wordpress.com/2009/04/13/how-to-indentify-a-big-block-olds-from-a-small-block-olds/

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