Author Topic: 4.3 to 5.7  (Read 3372 times)

Offline Blazin

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4.3 to 5.7
« on: June 09, 2007, 10:04:59 am »
Will the 4.3 standard fly wheel work on a 5.7 motor? Have an 87, standard shift with blown up 4.3, putting an 87 350 from and auto truck. Never played with the 4.3s much. What size clutch did they have? I have a 5.7, std. ECM to swap as well.
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Offline VileZambonie

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Re: 4.3 to 5.7
« Reply #1 on: June 09, 2007, 12:05:40 pm »
so you have an 87 350 going into what year was the 4.3? truck?

87 4.3L Flywheel part #10105832

87 5.7L Flywheel part #10105832

but if your 4.3L has a two piece rear main
 Like an 85 the part# is 3991469
« Last Edit: June 09, 2007, 12:09:50 pm by VileZambonie »
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Offline Blazin

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Re: 4.3 to 5.7
« Reply #2 on: June 09, 2007, 01:11:56 pm »
Both are 87s, the truck with 4.3 and the 350 going in. I know the motor will bolt up etc. and I know the 4.3 is a 5.7 missing 2 cylinders but didn't know if the flywheels were the same. And if the 4.3s had a small clutch. If they do I will find a one piece rear seal flywheel that will accept a 12" clutch.
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs