350 SBO Swap

sldwys

Greasemonkey
Nov 21, 2020
134
28
I’ve tossed and turned over an engine swap. Posted on here several times about doing one. Even bought a core 425.

I’ve had my 442 for about 6 months. I want more power to cruise. I’m about 90 percent sure I’m buying an Olds 350 motor tomorrow (72 350, .30 over with edelbrock performer cam) for my 85 442.

My concerns are doing the swap and being able to put the 307 back in one day. How can I go about ensuring this?

1. Also, will I have to cut any wires, splice, etc. What happens to most of the harness?

2. Can I use the stock carb and computer setup. Is it worth evening doing the swap if I go this route?

3. What are the bare bones connections needed if I go stand alone carb/ dist. Not use computer at all.

4. What about lockup torque converter being electronically controlled. How to work around this?

5. Should I buy new motor mounts?

6. Anything else I forget
 
Oct 14, 2008
7,080
113
Melville,Saskatchewan
You can swap the 350 right in. What pistons are in that 350? What number and letter in on your current 307 heads? Flat top pistons would potentially put your compression too high especially with the factory timing curve. The 24cc usual cast replacement pistons put you around 8 to 1, they would work even with the 7A 307 swirl ports super aggressive timing curve. The Performer cam should work fine with the CCC system. The wide 114 LSA should help and only being a 204/214 duration as well.
 

sldwys

Greasemonkey
Thread starter
Nov 21, 2020
134
28
You can swap the 350 right in. What pistons are in that 350? What number and letter in on your current 307 heads? Flat top pistons would potentially put your compression too high especially with the factory timing curve. The 24cc usual cast replacement pistons put you around 8 to 1, they would work even with the 7A 307 swirl ports super aggressive timing curve. The Performer cam should work fine with the CCC system. The wide 114 LSA should help and only being a 204/214 duration as well.

I have 5A Heads on the 307. The pistons in the olds 350 are sealed power. Seller said roughly 9:1 compression. This isn’t a high dollars engine but a deal for me.

So I won’t have to change prom codes or programming for timing/carb.
 

sldwys

Greasemonkey
Thread starter
Nov 21, 2020
134
28
You can try running it on the CCC, but I think you'll be leaving a few ponies out to pasture. I'd ditch the CCC in favor of a basic HEI and carb.....

That’s really what I want to do. Ditch the ccc. But then maybe he torque converter lockup comes into play. What do I do there. Also, don’t want to have to cut any wires from original harness if possible.
 

64nailhead

Goat Herder
Supporting Member
Dec 1, 2014
2,894
113
Upstate NY
That’s really what I want to do. Ditch the ccc. But then maybe he torque converter lockup comes into play. What do I do there. Also, don’t want to have to cut any wires from original harness if possible.
Super easy to overcome, don't let that stop you. Ditching the CCC is a GREAT idea. You can do it a number of ways and still have the 'factory correctness' look until the air cleaner is removed. 1st, and always, I recommend a TBI system such as a Holley Sniper - hide the O2 sensor in a crossover behind the trans. A second safe and easy plan is Fleming's comment.
 
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Reactions: Rktpwrd
Oct 14, 2008
7,080
113
Melville,Saskatchewan
With the CCC disabled, the speed sensor for the cruise control and A/C relay needs grounded. Get the TCI lock up kit. Unless they have 6cc pistons and early heads or flat top and #8 heads, it won't have 9 to 1 compression.
 

sldwys

Greasemonkey
Thread starter
Nov 21, 2020
134
28
With the CCC disabled, the speed sensor for the cruise control and A/C relay needs grounded. Get the TCI lock up kit. Unless they have 6cc pistons and early heads or flat top and #8 heads, it won't have 9 to 1 compression.
Thanks for all the info. Still debating on buying it and what rabbit hole I want to go down. At the end of the day, was just trying to get a little pep in my car for cheapest route possible.

I’m still learning about these cars and the nuances that come with them. I’m only 6 months in.
 

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