Olds 350 to Chevy 350 Swap

565bbchevy

Geezer
Aug 8, 2011
9,209
113
Michigan
I typically don't run A/C in my cars. Heat is an exception but I now live in an area where it doesn't get as cold in the winter months, and I don't plan to drive this thing in the winter much anyway due to salt.
I am just saying long term you might regret removing the AC, I wish I would have somehow kept the AC in my Monte with the BBC but the engine physically doesn't fit with case in there but I installed a heat only case to give me clearance because I can not stand the look of a block off plate especially in a SBC car where the engine fits with no clearance issues, once it's gone it is 3 times the work to reinstall. JMO
 
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565bbchevy

Geezer
Aug 8, 2011
9,209
113
Michigan
hard to tell with all the gunk but it's there:

View attachment 204442

I got everything but a flexplate and a belt drive.
That's a one piece so you will need a specific weighted flexplate, they make factory replacements and upgraded thicker ones.
Did you hear this SBC run?
 

Ernest

Master Mechanic
Apr 28, 2016
346
63
Texas
Curious, is that a 305, because GM used the log style(inline across all the exhaust ports) vs the 350 that used a manifold that the exhaust curved downward around each spark plug and ran much closer to the engine mounts.

When it comes to flexplates... look at the starter mounting holes on the block, if they are diagnal, you will need the larger diameter 168tooth, if the holes are straight across, you will need the smaller diameter 154tooth, but im willing to bet its straight across, the diagnal holes where used on pre '86 engines i believe.
 

zipties

Apprentice
Thread starter
Feb 2, 2022
57
18
Curious, is that a 305, because GM used the log style(inline across all the exhaust ports) vs the 350 that used a manifold that the exhaust curved downward around each spark plug and ran much closer to the engine mounts.

When it comes to flexplates... look at the starter mounting holes on the block, if they are diagnal, you will need the larger diameter 168tooth, if the holes are straight across, you will need the smaller diameter 154tooth, but im willing to bet its straight across, the diagnal holes where used on pre '86 engines i believe.
It's a 305, nothing special. this is not a permanent motor for it and not a performance application, just something to get it back on the road.

not sure why the 305 gets dogged so much, they aren't bad motors for just getting around.

good to know for the flexplate. I know 86 thru 88 was a wonky year for sbc parts changeover so I'll double check.
That's a one piece so you will need a specific weighted flexplate, they make factory replacements and upgraded thicker ones.
Did you hear this SBC run?
I'll probably just source one from a yard or see how pricey an OE replacement is from a parts place.

motor ran when pulled but it was a fairly old short vid. I've already opened it up for inspection since I'd better change anything internal out now while I got it out
 
Oct 14, 2008
8,254
113
Melville,Saskatchewan
That Olds 350 probably just needed a pan/pickup clean out and new timing set. It had headers and everything. Do you have all the sbc accessory brackets and pulleys, you will need them. A lot of work for a 305.
 
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zipties

Apprentice
Thread starter
Feb 2, 2022
57
18
That Olds 350 probably just needed a pan/pickup clean out and new timing set. It had headers and everything. Do you have all the sbc accessory brackets and pulleys, you will need them. A lot of work for a 305.
It's off to a better home now where it can be brought back to life or at least get another motor running again.

unfortunately, olds parts are too hard to come by here. None of my local yards have anything. I have a mountain of SBC parts and need somewhere to use them; I have most everything I need to finish a nice 383 build save for the right intake and a brand new MSD box. That will probably find its way into the cutty at some point.

i don't ever plan on putting an LS in it so getting it prepped for a nice SBC is a good milestone for the car.
 
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zipties

Apprentice
Thread starter
Feb 2, 2022
57
18
some pics of the trans. unsure of the year, it has a plug that has nothing connected to it. says Buick on it lol.

20220819_200544.jpg


20220819_200558.jpg


Really just for documentation. trans gives me no issues, shifted smooth and only leaks a little bit. i'll replace it eventually but not now.

got a flexplate for this year to be safe. picking it up tomorrow. gonna try and have a bow on this (get it) by the end of the month..
 

zipties

Apprentice
Thread starter
Feb 2, 2022
57
18
also, any tips for getting to the bolts on the olds motor mounts? they're almost impossible to even see through the holes i'd usually put an inset wrench through.

guessing that squeezing above the lower A arm would be the best choice. I have someone who needs these mounts so I don't wanna hack it up.
 

565bbchevy

Geezer
Aug 8, 2011
9,209
113
Michigan
any tips for getting to the bolts on the olds motor mounts?
I just cut the nuts/bolts off the Olds mounts and spent my time bolting in the SBC frame mounts.
 
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Oct 14, 2008
8,254
113
Melville,Saskatchewan
some pics of the trans. unsure of the year, it has a plug that has nothing connected to it. says Buick on it lol.

View attachment 205099

View attachment 205100

Really just for documentation. trans gives me no issues, shifted smooth and only leaks a little bit. i'll replace it eventually but not now.

got a flexplate for this year to be safe. picking it up tomorrow. gonna try and have a bow on this (get it) by the end of the month..
Either a TH250C or a TH350C. If there is a stud and nut for band adjustment by the cooler lines, it is the weaker TH250C. In good condition, it will live many miles behind a 305.
 
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