1971 Swinger 318, conversion to a 6cyl/special motor mounts needed

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out west bob

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I pulled the 318 out and am installing a 6cyl but being I am leaving the V8 K member intact, I need the special motor mounts which allow me to do this conversion. Any help locating them would be appreciated!
 
Good luck with that. I am unaware of anyone that makes conversion mounts for what you want. It would be so much simpler to swap to the slant six K frame. Is there any particular reason you want to keep the V-8 K frame?
 
There are no "special motor mounts" for a V8 to slant 6 swap. Only if you're doing the opposite.
On a '72 K frame (applies to '67-'72), the left (driver's side) K frame mount is the same whether slant 6 or V8, so that side will bolt up with stock factory slant mount brackets of the correct year (stay away from '66 and earlier mounts, or '73 and later mounts, they are completely different designs from what you have).
On the passenger side, however; the V8 K frame mount is taller than a slant six mount (by about 2" is what comes to mind, but my mind is highly unstable :)). There is no way in he** I'd cut down a factory small block K frame mount, and if you're determined to "leave the K frame intact"; that only leaves the option of shortening the passenger side engine bracket by 2" (or whatever the actual number is).
So, break out the hacksaw and welder- that's about the only way you're going to git 'er done.

P.S.- You DO know the transmission from a 318 won't fit a slant 6, right?
 
no such animal exists to my knowledge. so you'd be looking fabbing your own mounts

personally i'd track down a factory 6 K and mounts. 67~76 all will work.
 
if you weren't on the wrong side of the world i would happily trade you. just bought a '72 swinger w/ a slant that i'm going to swap out.
 
I pulled the 318 out and am installing a 6cyl but being I am leaving the V8 K member intact, I need the special motor mounts which allow me to do this conversion. Any help locating them would be appreciated!
OK, I just gotta know why?

In 54 years of hotrodding, never once did I swap to a slanty, lol.
Altho, I did rebuild a few.

If it's for fuel economy, that's almost a myth.
I'm pretty sure that I can get better fuel economy out of a hi-compression, modest cam, overdriven M/T 360, than any factory non-overdrive 225slanty ever made; and I'll give you the benefit of choosing any Mopar trans and any Mopar rear gear.
Your 318, properly rebuilt, can do even better.

If it's cause the 318 is wore out, and you just happen to have a slanty with a transmission, well that's another matter.
 
OK, I just gotta know why?

In 54 years of hotrodding, never once did I swap to a slanty, lol.
Altho, I did rebuild a few.

If it's for fuel economy, that's almost a myth.
I'm pretty sure that I can get better fuel economy out of a hi-compression, modest cam, overdriven M/T 360, than any factory non-overdrive 225slanty ever made; and I'll give you the benefit of choosing any Mopar trans and any Mopar rear gear.
Your 318, properly rebuilt, can do even better.

If it's cause the 318 is wore out, and you just happen to have a slanty with a transmission, well that's another matter.
My 66 Barracuda was born with a 273. When I got it there was a 360 in the engine bay. I wanted to go fast so I installed a 170 slant six :)
 
Good luck with that. I am unaware of anyone that makes conversion mounts for what you want. It would be so much simpler to swap to the slant six K frame. Is there any particular reason you want to keep the V-8 K frame?
Basically ,just didn't want to deal with locating a 6 frame then switching it, if I could make the 8 frame work. The left side mounts line up ok, its just the right side thats completely different! At this point I have removed the R mount from the frame using a disc grinder cutter and a saws _all so now just need to get something designed and welded in to accept the engines rubber mount.
 
There are no "special motor mounts" for a V8 to slant 6 swap. Only if you're doing the opposite.
On a '72 K frame (applies to '67-'72), the left (driver's side) K frame mount is the same whether slant 6 or V8, so that side will bolt up with stock factory slant mount brackets of the correct year (stay away from '66 and earlier mounts, or '73 and later mounts, they are completely different designs from what you have).
On the passenger side, however; the V8 K frame mount is taller than a slant six mount (by about 2" is what comes to mind, but my mind is highly unstable :)). There is no way in he** I'd cut down a factory small block K frame mount, and if you're determined to "leave the K frame intact"; that only leaves the option of shortening the passenger side engine bracket by 2" (or whatever the actual number is).
So, break out the hacksaw and welder- that's about the only way you're going to git 'er done.

P.S.- You DO know the transmission from a 318 won't fit a slant 6, right?
Having work for Chrysler for 14 yrs starting in 1974, I have a decent amount of knowledge as to what fits what, interchanges, etc. I'd picked up a 1986 AT trans for this project and overhauled it, so should be ok there. Now, after having done the dastardly deed of removing the R frame mount , I'm ready to devise a frame mount that will accept my engine rubber mount. Moving along, albeit slowly.
 
Having work for Chrysler for 14 yrs starting in 1974, I have a decent amount of knowledge as to what fits what, interchanges, etc. I'd picked up a 1986 AT trans for this project and overhauled it, so should be ok there. Now, after having done the dastardly deed of removing the R frame mount , I'm ready to devise a frame mount that will accept my engine rubber mount. Moving along, albeit slowly.
1724112765129.png

I think that this is the set up that I need? It's different than the earlier ones for sure! If I could locate that metal bracket that bolts to the engine I'd be good to go! Anyone got one to sell?
 
OK, I just gotta know why?

In 54 years of hotrodding, never once did I swap to a slanty, lol.
Altho, I did rebuild a few.

If it's for fuel economy, that's almost a myth.
I'm pretty sure that I can get better fuel economy out of a hi-compression, modest cam, overdriven M/T 360, than any factory non-overdrive 225slanty ever made; and I'll give you the benefit of choosing any Mopar trans and any Mopar rear gear.
Your 318, properly rebuilt, can do even better.

If it's cause the 318 is wore out, and you just happen to have a slanty with a transmission, well that's another matter.
318 had 300k on it and was getting tired! And yes, I had a decent 6 laying around, and had just acquired an AT that I could rebuild and use. Selling the V8 and AT out of the car supplied enough $$ to cover related switch costs, plus some extra for whatever. Basically I just like the simplicity of working under the hood with a 6. And being 75 now, my need to go fast and collect tickets has passed, lol.
 
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