What should I do to my Cutlass?

thelifeafter245

Not-quite-so-new-guy
Thread starter
Jul 27, 2020
12
3
If they will sell with all the accessories, motor AND frame mounts makes the swap much easier. Make sure you don't have a dreaded TH200, that might not survive a 307.

Thanks for the info, I'm fairly certain I have the th250 since it has the X on the pan and the band adjuster by the coolant lines, if I'm wrong please let me know, hate to put the motor in and the trans die after a couple of days.
 
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thelifeafter245

Not-quite-so-new-guy
Thread starter
Jul 27, 2020
12
3
IF you go with a 307/350 Olds V8 engine, you will need to obtain Olds frame mounts. G-body mounts preferably. AND you need to ensure to put them in the right spot if you do. On the rear of the frame you put the "long" side up, and the bottom bolt goes in the last hole rearward and the top bolt goes into the SECOND TO THE LAST HOLE REARWARD. They should be facing pretty much straight up and down. The 307/350 would drop right into place after that. Now, if you go down this route, you'd have to decide whether to stay on the computer or not. If you do, you'll need to get a V8 CCC box. Perhaps you may need other connections as well, I don't know. I've never converted a V6 to V8 with CCC. May be easier to get a NON-CCC HEI and carburetor and deal with it that way. There's other considerations like carb linkage to cables and trans cable hookups, etc., that will need dealing with too. Non-lockup torque converter? I don't know what an 84 V6 comes with. But it can be figured out.

Frame mounts look like this installed.


Wow I really appreciate all that info, it will be very helpful. So again I've never motor swapped anything, are these frame mounts something you order online or do they have to be pulled from a donor car? And once I have the frame mounts in place any 307 with standard motor mounts will bolt right in? I'm most likely going to go with a no computer swap, just gonna get a decent carb and a hei distributor. I'm fairly certain its non lockup but I'm not 100% sure.
 

blk7gxn

Royal Smart Person
Feb 7, 2019
1,092
113
Wow I really appreciate all that info, it will be very helpful. So again I've never motor swapped anything, are these frame mounts something you order online or do they have to be pulled from a donor car? And once I have the frame mounts in place any 307 with standard motor mounts will bolt right in? I'm most likely going to go with a no computer swap, just gonna get a decent carb and a hei distributor. I'm fairly certain its non lockup but I'm not 100% sure.
Check here first, I'm sure someone has a set of MM they would be willing to sell you for reasonable :)
 
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Reactions: fleming442

69hurstolds

Comic Book Super Hero
Supporting Member
Jan 2, 2006
4,705
113
Yeah. I'd check here first if you go that route. There's plenty of people that have yanked 307 in favor of LS engines and they no longer would need the Olds motor mount pads.
 
Oct 14, 2008
6,728
113
Melville,Saskatchewan
Yes, you need the frame pads from a donor car. Honestly the only decent aftermarket motor mounts are from Supercars Unlimited. All rwd Olds powered cars from 73 to 90 use the same motor mounts.
 
Last edited:
Oct 14, 2008
6,728
113
Melville,Saskatchewan
They usually throw them in the trash because "who the hell wants an Olds engine?"

This guy too. The SBO 350, non windowed main, talking mid 70's version usually go for song and unlike nearly any other make of engine from the Malaise era, still are in good to excellent condition. The $400 73 Olds 350 with a good 2004R, with something in itself, runs excellent.
 
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thelifeafter245

Not-quite-so-new-guy
Thread starter
Jul 27, 2020
12
3
Thank you all for the information, y'all have given me a lot to think about. I'm thinking I'm going to go with a 307 and get new gaskets for my th250. I'm definitely going to check here for the frame mounts. Im not sure how it works here, do I need to close the thread? Also one last thing, I was reading some spec sheets and my car could possibly have a th250 or th250c, I believe the C means lockup torque converter. Is there any way to check which my car has without pulling the transmission?
 
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