What K Member and Transmission Mount ?

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68Fastback402

68Fastback402

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I am in the process of swapping from a 360 to a 400 Stroker with 727 TorqueFlight
I heard you had to make a custom K-Member
Thanks for any input
 
Not needed. Just get the same trans mount that came in it. It will bolt up to either trans...

BTW what car are you putting this in??? May make a dfference... I'm assuming it's a 68 fastback like your screen name....
 
Just get the Schumacher mounts, they work and work well. You can make your own k frame as Jim posted above. Or if you're deeper in the wallet, an aftermarket k frame is another option.
 
I just removed a 400 from a 74 Duster that has a spool mount K-member. It was attached to the block with some kind of OEM mounts that bolted to the block and dropped down on the slots. Haven't even researched exactly what I have, but I do know it fit like it was suppose to be in there. I am going with a 440 and a motor plate when I put it back together. I'll post a photo today if I get a chance to show you what they looked like.
Tom
 
PROSTOCKTOM said:
I just removed a 400 from a 74 Duster that has a spool mount K-member. It was attached to the block with some kind of OEM mounts that bolted to the block and dropped down on the slots. Haven't even researched exactly what I have, but I do know it fit like it was suppose to be in there. I am going with a 440 and a motor plate when I put it back together. I'll post a photo today if I get a chance to show you what they looked like.
Tom
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Good close photos of this setup would be much appreciated, by myself and I'm sure by others
 
Here's the photos Jim and like I said, I bought this running 74 Duster drag race car that had the 400 in it.
Engine was sitting and looking correctly positioned in the engine bay.
The motor mounts have multiple part numbers depending on what the application was and mine have the white paint designation on them which corresponds with part numbers 3642814 and 3642815.
However after digging a little further it appears Mopar boxed these two part numbers up and sold it as a kit to install a big block on a small block V8 spool K-member as Mopar Performance kit # P4120757
"Can be used to swap a big block engine where a small block was used in vehicles up to 1978 A, B, C-body"

However they are nothing more than a factory mounts for a 1973 1974 1975 1976 Dodge and Plymouth B & C-body vehicles with 400-440 engines.

Just happened to find a seller on eBay that has several new Mopar kits available for $199.95
1973 1974 1975 1976-78 NOS MoPar MOTOR MOUNTS B,RB KIT

Or if you want to save a $100 you can buy these
NOS Mopar Motor Mounts 1973-76 B & C body big block spool type 3642814-3642815

Then if all else fails you can probably find some cheap Chinese ones from RockAuto or some other Asian quality retailer, but why would you not want OEM quality Mopar mounts?

Looks like the mystery of installing a big block in A-body is debunked if you have a V8 spool mount K-member.
Hope the photos and information will provide some knowledge to help more of you get a big block in your A-body
a little cheaper and easier.

Tom












 
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I can tell you right now that the motor sat too far forward with the stock V8 k-member (which that is).
 
Jim Lusk said:
I can tell you right now that the motor sat too far forward with the stock V8 k-member (which that is).
Click to expand...
It was fairly close to the firewall and if was any closer I would have had a hard time getting the bell bolts out.
Either way it is a cheap and easy way to get a big block in an A-body.
Tom
 
PROSTOCKTOM said:
It was fairly close to the firewall and if was any closer I would have had a hard time getting the bell bolts out.
Either way it is a cheap and easy way to get a big block in an A-body.
Tom
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yes, if transmission mount and trans cross member is correct, motor of cause has to sit correct (back and forward) also... or is there a special transmission mount/cross member with this application?
Just trying to learn something here...
 
My transmission was mounted in the factory spot with a regular old transmission mount.
If Mopar sold the engine mounts as a kit to install a big block on a V8 spool mount K-member it had to be in the correct position.
I can not possible understand why Jim Lusk thinks it is to far forward. Any further back and you might as well drill holes in the firewall to get the bellhousing bolts out. Since I just took it all apart and know how it fit I am going to say it's correct.

Tom
 
PROSTOCKTOM said:
My transmission was mounted in the factory spot with a regular old transmission mount.
If Mopar sold the engine mounts as a kit to install a big block on a V8 spool mount K-member it had to be in the correct position.
I can not possible understand why Jim Lusk thinks it is to far forward. Any further back and you might as well drill holes in the firewall to get the bellhousing bolts out. Since I just took it all apart and know how it fit I am going to say it's correct.

Tom
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The old school trick was to use a certain set of C body mounts to stuff the B engine in there. Often times, this would result in the engine sitting either too far forward, too high and in some cases, off to one side, but it would work. It wasn't till Schumacher came along several years back with the swap kit idea to put the motor in a factory like position that this changed.
 
It's simple. You have a stock 73-76 V8 K-member with stock 74-78 passenger car big block motor mounts. IF that combo fit the motor in the right place then Chrysler NEVER would have modified that same K-member to use those same mounts. So, your argument is with the Chrysler engineers who came up with the Direct Connection k-member to use those same mounts to put the motor in the proper position.
 
Jim Lusk said:
It's simple. You have a stock 73-76 V8 K-member with stock 74-78 passenger car big block motor mounts. IF that combo fit the motor in the right place then Chrysler NEVER would have modified that same K-member to use those same mounts. So, your argument is with the Chrysler engineers who came up with the Direct Connection k-member to use those same mounts to put the motor in the proper position.
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Well tell me Jim how much closer can it go to the firewall since you say it was in the wrong place?
You can say it's not correct, but I am telling you and showing you it was as far back as it could go.
You might have had a different setup, but this one was all the way back regardless of you saying it was not in the correct spot.



[url=https://postimage.org/]

Tom[/url]
 
All I can do is guess that perhaps the k-member was moved back. I'm not with the car so I have no idea what else was done. Again, IF this setup worked without a modded k-member there never would have been a Direct Connection k-member (what I have been copying since the late 1980s) OR Schumacher mounts that require shortening the driver side saddle.
 
Looks like the DC k member to me. I have one in my dart. Pass side looks the same. Drivers side on mine is all hacked up to clear a big oil pump and external line. But I think thats the DC part.
 
If your going with a plate swap out that k for another k that you can clean up. Cut off everything not needed. Than sell that k to the OP for a fair price. Be a shame to cut on it...
 
hangn0ut said:
Looks like the DC k member to me. I have one in my dart. Pass side looks the same. Drivers side on mine is all hacked up to clear a big oil pump and external line. But I think thats the DC part.
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Nope, not a DC. It IS a STOCK 73-76 V8 k-member. The saddles are cut and moved rearward on the DC k-member.
 
Well I just took a look and that pass side saddle is right where mine is. Looking close at that photo I can see where the original saddle tower was before it was removed. That k has been modded.
 
hangn0ut said:
Prostocktom,pass side lower control arm sure looks funny. Like its tearing out.
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Passenger side control arm does look funny because the bushing is wore out and letting it tilt downward in the front.
Like Jim said, It's not been modified like a Direct Connection K-member. I watched his very informative videos on how to build a DC K-member and can tell you without a doubt the mounts on mine have never been messed with. How the previous owners got it to fit is unknown to me. All I can say is, It sat in the car correctly on the mounts and the 727 transmission was bolted to the stock crossmember, in the stock holes.
I am not going to be cutting this K-member up or using it in my build. I have another one to use in it, and plan to save the other one for a 65 Valiant Signet that had a Slant 6 in it.
Tom
 
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My DC k was made from a blank,I guess you would call it. It never had any other mounts on it. Whatever k you use I would suggest removing that lip that surrounds where the oil sump would be. And strenghten the steering box mount. The box moves around quite a bit and needs additional bracing. You know that k wont fit a 66 signet, right?
 
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