inline six compatability

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longbeach

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I have a 350 in my 86 chevy K20 and I want to swap to an inline six. I see a lot of 60's and 70's sixes for sale. Not so many 80's. How far back can I go and still have the inline six mate up with a TH400 transmission?
 

wanderinthru

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I have a 350 in my 86 chevy K20 and I want to swap to an inline six. I see a lot of 60's and 70's sixes for sale. Not so many 80's. How far back can I go and still have the inline six mate up with a TH400 transmission?
Not that I have anything against a 6, They do have their strong points. Personally never ran one with an auto. Could I ask why you want to go from a 350 to I6?
 

mtnmankev

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One of my favorite things about Chevy is they used the same bellhousing pattern for sixes and eights, with only a couple exceptions.
I wish F*rd would have been that smart.
230, 250,292, 302,305,307,327,350,400,454 etc all use the same bellhousing pattern.
And probably more engines too, smaller and bigger than this list.
The motor mounts will be in a different location, if you're lucky, they drilled the frame so all you gotta do is slide the mounts and bolt them in.
May have to cut the rivets off.
 

longbeach

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Thanks to everyone for the replies. As far as reason to change. Just nostalgia and ease of servicing. I had a K20 and a K10 years ago with the inline six. Just loved them. I'll check out the Novak Guide. Thanks
 

75gmck25

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If you want to keep things simple, the 292 seems like the best choice since it was originally available in the squarebody trucks. That means you should be able to buy pieces and parts by just looking up an ‘86 3/4 ton with a 292.
 

longbeach

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Good point. But 292's seem to be in short supply. I'm looking, may have a line on on one
 

Peter coppola

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I have a 350 in my 86 chevy K20 and I want to swap to an inline six. I see a lot of 60's and 70's sixes for sale. Not so many 80's. How far back can I go and still have the inline six mate up with a TH400 transmission?
I have a 1979 C10 which had the original 250 I-6, HEI Distributor and 2BBL Carb. I am switching to a 350 V8 as I am building a mild street rod. I pulled the I-6 and it is sitting on a dolly. I live in NJ 08848. It is for sale. Motor has 150K on it. It is complete, does not smoke and ran on the day that I pulled it three months ago. Reasonable offer appreciated. I have videos of it running the day I yanked it.


There may be others closer to you but figured I would send this over. I am willing to seperate from the the 3 speed manual.
You must be registered for see images attach
 

longbeach

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Peter, thanks for the offer but there are some for sale locally. I appreciate you reaching out. Good luck with your build.
 

Turbo4whl

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One of my favorite things about Chevy is they used the same bellhousing pattern for sixes and eights, with only a couple exceptions.
I wish F*rd would have been that smart.
230, 250,292, 302,305,307,327,350,400,454 etc all use the same bellhousing pattern.
And probably more engines too, smaller and bigger than this list.

You got most all of the old engines, add 366 and 427.

But then the newer one's too? 4.3L, 4.8L, 5.3L, 6L, and 8.1L
 

mtnmankev

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My memory is not what it used to be.
The 265 might also work, but I'm sure the 235 was different.
And I don't do metric engines, I am a cubic inches person.
 

oldretiredafguy

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235 is I think an inline six from the mid 50's. 216 235 261 family.
 

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