Author Topic: power plant swap  (Read 4949 times)

Offline murraygmc

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power plant swap
« on: February 21, 2009, 02:33:27 pm »
OK iv got a 86 4.3  and I'm thinking of putting a 79 350 in so what are the things different i need to know   will the fly wheel inter change  motor Mount  change  and any thing else i might Need to know  how will the exhaust  come out ? just like the 4.3   thanks   it is going in to a 85 4x4  is the 79 350 a 4 bolt main
« Last Edit: February 21, 2009, 02:36:32 pm by murraygmc »
85 gmc high serria 4x4

Offline Captkaos

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Re: power plant swap
« Reply #1 on: February 22, 2009, 09:09:02 am »
Everything on the motor will swap out, but the I think the motor mounts are different

Offline Blazin

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Re: power plant swap
« Reply #2 on: February 22, 2009, 09:11:52 am »
Fly wheel on the 4.3 is a one piece isn't it. 79 would be a two piece?
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Offline Captkaos

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Re: power plant swap
« Reply #3 on: February 22, 2009, 09:15:06 am »
Hmmm I think your right Blazin.

Offline hilton850

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Re: power plant swap
« Reply #4 on: February 22, 2009, 04:19:49 pm »
is the 4.3 internal balance or external balance? 
Blazin, do you mean external balance when you say 2 piece flywheel?
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Offline VileZambonie

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Re: power plant swap
« Reply #5 on: February 22, 2009, 07:03:11 pm »
He means 2 piece rear main seal not 2 piece flywheel
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Offline murraygmc

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Re: power plant swap
« Reply #6 on: February 23, 2009, 11:07:51 am »
ok thanks  guyes hear is one thing tho the guy wants bothe my 4.3 mortors an iv got a 389 out of a 66 catlina with a 2 speed powerglide behind it  most of it is junk but the power glide works fine any one know what the power glide is worth????
85 gmc high serria 4x4

Offline bigkountry

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Re: power plant swap
« Reply #7 on: February 25, 2009, 10:33:44 am »
I sold a glide last year that had been outside for two years. Turned it over, dumped the water out of it and sold it to a guy for $100. He watched me do all of this but wanted it anyways.

Look for a speed shop or dragstrip/swapmeet to unload the glide. They are only good for resto or racing really.
81 Scottsdale K10 "Under construction"

Offline joesgarage71

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Re: power plant swap
« Reply #8 on: February 25, 2009, 10:58:48 am »
Theres guys out there looking for those 389's don't junk it! Find the Pontiac sites and sell it.
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Offline joesgarage71

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Re: power plant swap
« Reply #9 on: March 05, 2009, 08:45:41 am »
Theres guys out there looking for those 389's don't junk it! Find the Pontiac sites and sell it.

 Hey a guy looking for a 389
http://www.hotrodders.com/ads/showproduct.php?product=5899&sort=1&cat=12&page=1

 You changed your first post, very tricky ::)
« Last Edit: March 05, 2009, 08:49:27 am by joesgarage71 »
78' K-20 355/SM465/twin stick 205 6" on 36's
14 bolt FF/big bearing Dana 44 4.56 gears

92' GMC C-1500 454/4L80E/14 bolt