K member swap

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Crank It Up!!!

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Got a new-be question for yall. Will I have to change out the K member in my 67 slant 6 Dart to install a small block V-8 in it? (360) Daaaaaaaaaaaaaaaaaaaaaaa ????????????????????????????
If so, what cars can I git one out of?
 
if you change k members the only direct bolt in one will be from a 67 v8 car as the idler arms are different you can put a 68-72 in it but you have to change idler arms also but i believe that is all and if you go with the spool mount k frame from 73-76 i believe you have to change the whole front steering set up to go with the k frame and suppousedly the spool mount are the best because of the design you dont break motor mounts if you have a healthy engine but if you put a torque strap on the 68-72 or the 67 k frame you wont tear up to many motor mounts either. Again like gtx said you could also go with the kit from schumacher i believe that kit is about 150 plus shipping Good Luck Justin
 
if you change k members the only direct bolt in one will be from a 67 v8 car as the idler arms are different you can put a 68-72 in it but you have to change idler arms also but i believe that is all and if you go with the spool mount k frame from 73-76 i believe you have to change the whole front steering set up to go with the k frame and suppousedly the spool mount are the best because of the design you dont break motor mounts if you have a healthy engine but if you put a torque strap on the 68-72 or the 67 k frame you wont tear up to many motor mounts either. Again like gtx said you could also go with the kit from schumacher i believe that kit is about 150 plus shipping Good Luck Justin
Bein a new-be, I dont know what a "spool" K frame is. Is the steering and suspention also better in the 73-76? Is it worth the time, money and trouble for a healthy street car? If I use my stock K frame and go tha mount kit method, wont I need heavier springs? What about control arms and ball joints. Are they tha same? I intend to convert to disc brakes. Will I need to git my spindles and control arms from a V-8 car?
 
they changed from a bisquit type motor mount to a spool type.
V8 and \6 upper arms are the same
 
The 68+ idler arm is a better design that the 67 arm, so if you wind up with a latter model k-member that is a good thing.

Up through 72 the motor mounts were two plates of steel with rubber bonded in between. If the rubber bond failed (which it did from time to time) the motor could flop around and damage other parts. In 73 they changed to what is refered to as the spool mount. The engine mount has a tube of steel on it with a rubber insert inside it. The k-member has two ears per side that the tube fits into and a bolt pases through front to rear. Failure of the rubber will not allow the engine to flop around. That is why they are considered to be a better design. But there are now after market mounts for the older style that have metal that interlocks and if the rubber was to fail the engine is contained. If you use them it's just as good as the spool mount system.

The \6 torsion bars are not really strong enough for even the \6 compared to what folks expect from a car today. I would recomend that you go with the .890" diameter big block bars with the small block v8. Nice firm tight ride that is not at all harsh.

The 72 an older disk brake set up for an A-body is scarce and parts are hard to come by. Most folks search out 73+ A-body disk brake set ups. All the parts are still available at the local parts store and they are relatively cheap. But in 73 mopar consolidated on a larger upper ball joint across all lines. So you will need the upper control arm from the doner car as well as the disk brake spindle and caliper mounting bracket. Likely you will be purchasing new rotors but grab the calipers and master cylinder to use as cores for rebuilt items. The lower ball joint on the disk brake car has larger mounting holes for the spindle than drum cars but otherwise is the same (you could drill out the drum lower ball joint to accept the larger bolt). It does not matter whether the disk brakes come from a \6 or v8 car they are the same.

In 73 the idler arm, pitman arm and center link changed. Either vintage can be used you just have to use all three from the same vintage. The difference is how the stud on the pitman and idler mount to the center link. Also, contrary to what you may have heard starting in 67 there is no difference between a \6 center link and a v8 center link (there was prior to 67).

Whether you go with after market mounts or get a different k-member should be driven by availability and price, there is not real functional advantage one way or the other. When I did the disk brake and v8 swap I was fortunate that I was able to pick up a complete 73 v8 Dart with disk brakes for nothing. Stripped all the parts I wanted or could sell and sent the rest of the rusted hulk to the junk yard.
 
use the schumacker mounts . a slant 6 k-frame is strong as a bigblock k-frame, there isnt any strength difference, when ya call schumacker ask them. measure the torsion bars first as the slant 6 tbars will give the front end good rise if you race it, Ive seen factory slant 6 t bars that were thicker than bigblock cars frrom the factory, the rules in racing is use the slant 6 torsion bar for small blocks and the smallblock torsion bar to a bigblock.
 
you may need to switch to a v-8 center link .some do some dont have to.
 
The '73-'76 K member has some advantages over your '67. The sway bar mounting system is much stronger, the steering and brakes are out of a B body, and the engine mounts will not separate and let the engine move around. New parts are a lot cheaper and more commonly available than the '67.
How you do the engine swap depends on how you get your disc brakes. If you find a car with discs on it, take the K member too. If it isn't a V8 K member, big deal, Schumacher has a kit for that too. If you get your discs as parts from a seller, keep your '67 K member.
If you move your battery to the trunk, the weight difference between the /6 and the V8 is pretty much offset, so you may not need torsion bars. Crank them up a little first. If they won't sit right for you, then change them.
 
use the schumacker mounts . a slant 6 k-frame is strong as a bigblock k-frame, there isnt any strength difference, when ya call schumacker ask them. measure the torsion bars first as the slant 6 tbars will give the front end good rise if you race it, Ive seen factory slant 6 t bars that were thicker than bigblock cars frrom the factory, the rules in racing is use the slant 6 torsion bar for small blocks and the smallblock torsion bar to a bigblock.

Factory \6 A-body bars are .830" in diameter or for heavy duty applications they are .850" in diameter the same as the light duty small block bar. Heavy duty small block bars are .870" in diamter and big block A-body bars are .890" in diameter. If you saw a \6 car with a bar bigger than .890" some one swapped it out, it wasn't from the factory, I could believe a factory screw up that wound up with some other factory diameter bar but not one bigger than the .890" bar. Also, remember B/E and C body cars have longer bars so they have to be bigger in diameter than an A-body bar to have the same rate. You can't compare diameters between the body styles.

If the car is close to 100% race than staying with the small bar is may help weight transfer but if it's mostly street driven with an occasional trip down the strip go with the bigger bar, you will be much happier with the ride and handling.
 
you may need to switch to a v-8 center link .some do some dont have to.

Starting in 67 there was no difference between the \6 and v8 center link. The 66 an older a-bodies with a \6 had a striaght center link that would not clear the oil pan of a v8, the v8's have a drop in the center. The 67+ center link all have a drop in the center and the 73+ has less drop because the idler and pitman arm mount from the opposite side but the center of the bar is still in the same place.
 
correct on the v-8 link ..810 drag racing. .830 6 production bar ,.870 resto 340, .890 resto 383 in A body.920 v-8 hd handleing, .990 solo and road racing,1.040 for hd solo and road racing,1.090 for oval track 1/4 mile racing and 1/2 mile oval track.1.140 for oval track 1/4 mile and 1/2 mile oval track racing. note the .810 bar .for 1/4 mile and a small block its the way to go for a big block .870 to 8.90 is the way to go. would you believe .890 bars on a factory 74 duster with slant 6? note the .810 bar, for good front end rise
 
rule of thumb is to use the slant 6 bars for a small block for racing and the small block bars for a big block racing 1/4 mile
 
easy to clear the center link on later straight slant 6 cars with a motor plate
 
uhhh yes the B and E bars are 41 inches long and the A is 35.8 so there is no comparison
 
going from a .830 slant bar spring rate of 100 aint gonna make much difference than the .870 120 rate which is resto 340 or the .890 rate of 130 which is the 383 t bar in my view..920 will make car handle better but is stiffer and not reccomended for racing, note the .810 bar is used for getting the front end up and is the reccomended bar for racing
 
WOW!!! When you guys git on a roll, you git on a ROLL. All this info is great. I appreciate it. But .......... somebody is gonna have to put all this in a nut shell and tell me which way is the best and most economical for a driver street car. It'll likely never go to a 1/4 mile track. My intentions are to build healthy street car with somewhere in the neighborhood of 450 +/- hp. turnin an auto trans. Tha jury hasnt come to a decision on what tranny yet. Some say tha 904 is tha way to go because its easier to turn where others tha 727 is better. ?????? I want whichever is gonna hold up and last the longest knowing that much of that depends on the build. I would like the car to have good weight tranfer but without looking at tha clouds. Also for it to handle half way decent at tha same time. I guess I'm lookin for somebody to lay out a good basic set-up that isnt gonna cost me a tha farm to put togather. Also without having to cross the entire country lookin for parts to do it.

You guys are great!!! I know I came to the right place for advise and whatever instruction I may need down tha road. THANKS TO ALL OF YOU!!!

More later.

Robert
 
there is no .850 bar listed in my m.p chassis manual

No idea what's in the Chassis Manual says but from the factory the standard bar for 318 cars and heavy duty \6 cars was an .850" bar, 340 cars came with heavy duty suspension and .870 bars and a 318 car with heavey duty suspension would have had the .870 bars. I have a set of .850" bars that came out of my 68 Barracuda. My car was a \6 car with heavy duty suspension. It had the .850" bars up front and 6 leaf springs in the back.
 
WOW!!! When you guys git on a role, you git on a ROLE. All this info is great. I appreciate it. But .......... somebody is gonna have to put all this in a nut shell and tell me which way is the best and most economical for a driver street car.

The conversion mounts will cost you $150. If you can find a v8 k-member for less go that route, they are easy enough to swap out. Irregardless of what has been said about weight transfer if the car is primarily a street car (even if you go to the strip occasionally) go with bigger than \6 bars. The .890" bars don't ride rough and make a dramatic difference in the handling of the car that you will enjoy every time you drive the car..

Definitely get disk brakes on the car. The 9" \6 drum brakes are woefully inadequate. Again if you can find a doner car in the junk yard the 73 and up factory system will be the most economical way to go. However, it might be cheaper to buy an after market kit compared to buy 73 and up parts off e-bay. Also, remember the 73+ stuff is going to have the bigger 4.5" bolt pattern so you will need new wheels but there are endless choices in the 4.5" size.

Again if you are going street car you want a 727 much more durable at the slight expense of robbing a little power. However, the 727 will also require that you shorten the drive shaft and get a new slip yoke to fit the bigger output shaft (unless you find a doner with a 727 that you can get the drive shaft from). Again it's a matter of economics. A 904 will be easier to come by but to beef it up will cost money. A 727 will be strong enough stock.

My 68 Barracuda was a \6 three speed manual car. My plan was always to do a v8 swap but I also new if the car sat to long that I would like never finish it so I made a plan and stuck to it. I recomend that you do that to. Here is my plan;

1. Do the paint & body work and redo the interior so I could drive the car as soon as possible. The rest of the activities I planned for winter when I was not going to be driving he car.

2. Start collecting parts for disk brake, rear end, cooling, 4spd and V8 swap.

3. The first thing I came across was the 4sp. I used an A833OD unit from an 81 pickup. This was actually swapped in when I was reassembling the car after paint.

4. I had an opportunity to pick up a 73 v8 Dart that donated disk brakes and the v8 k-member.

5. I also picked up an 8.25 rear end at about the same time. I rebuilt the rear end with 3.5 gears and sure-grip.

7. I also picked up a set of big bolt pattern rally wheels and refinished them.

6. I swapped to disk brakes (and installed the .890 t-bars at the same time). I also swapped in the 8.25. I had the tires that were on the sbp wheels swapped to the rally wheels. I now had a \6 4spd car with disk brakes and an 8.25 rear end.

7. I found a rebuildable 360 core for short change and rebuilt that motor over the winter. I had also picked up a radiator, v8 bell housing, flywheel, clutch and headers. The \6 had 6 into two headers and when I had an exhaust bent up for it I went duals and had it configured so all I had to do was cut the pipes at the end of the tranny to adapt them to the v8.

8. I then swapped in the v8 using the v8 k-member from the Dart doner.

After the paint and body work I did the all the rest over a 5 year period but never had the car of the road for more than a day or two during the prime cruising season of April through November. I have put 30k miles on it with the \6 and another 20k miles with the v8. Every winter I plane for another upgrade. This past winter I swapped on 15" wheels, the winter before I did manual to power steering and the winter before that I swapped in another exhaust that is nore appropriate for the power the 360 makes. I am now collecting parts for AC.
 
My 68 Barracuda was a \6 three speed manual car. My plan was always to do a v8 swap but I also new if the car sat to long that I would like never finish it so I made a plan and stuck to it. I recomend that you do that to. Here is my plan;
THATS GOOD STUFF!!! Unfortunately I cant do that with this one. This car has been sitting outside for over 25 years. The inspection sticker still on the windshield says 6 of 1982. As you can imagin, anything thats rubber is dry rotted. In paticular all the front end bushings. I'm gonna have to start there. That being true, the possible K frame swap and disc brake conversion will come first followed by the rest of the undercarriage. The interior is toast. All there but toast just tha same. I dont know how long ago the window got broken out. Some kind of critters have been living (and dying) in it. Including a 4' snake who which I hope is long gone. I found his shed skin under tha hood. As far as the motor goes, I'll be in absolute shock if I can git the motor to even turn much less run. We dont git too many hard freezes down here but in the last 26 years we've had a few. For all I know the block may be cracked. ?????? I dont think I really have a choice but to strip the entire car and start from scratch. I probobly wouldnt have even started this project if the body wasnt in such good shape and the price hadnt been right. As in FREE!!! The car was given to me by its deceased owners son. It was his moms. I dont think anybody drove it after she died. It either has just over 53,000 or 153,000 miles on it. Knowing the lifestyle of its elderly woman owner, I'm leanin towards the lesser of the mileage. However I just cant believe the womans hiers would have let a 53,000 mile car just sit and go to ruins. It was probobly in mint condition in 1982. So as much as I like your plan of attack, I just dont think its gonna work on this one. Hopefully I'll be able to post some pics of it in a few weeks. Meanwhile, I'm keepin my eyes pealed for a doner car.

Could somebody please give me a list of doner models??? Years would be helpfull too.

Found this;

A Body--1960-1976.
Plymouth: Valiant (all), Barracuda ('64-'69), Duster ('70-'76), Scamp ('71-'76)
Dodge: Lancer ('61-'62), Dart ('63-'76), Demon ('71-'72), Dart Sport ('73-'76)
Wheelbases:
106: '63-'66 Valiant; '64-'66 Barracuda; '63-'66 Dart wagons
106.5: '60-'62 Valiant; '61-'62 Lancer
108: '67-'73 Valiant; '67-'69 Barracuda; '70-'76 Duster; '71-'72 Demon; '73-'76 Dart Sport
111: '71-'76 Scamp; '74-'76 Valiant; '63-'76 Dart (ex. wagons); Canadian Valiant (Dart front clip, Valiant body, 111" wb)

Now which ones can I use for a possible K member swap for a V8? I assume anything that has a V8. I know disc brakes didnt come out untill 73 so that pretty much narrows my search for them. Pretty sure I read that if I can find a complete 73 and up A body anything, I should git everything including the K member, suspention, steering, spindles and all the brake components. If no K member swap, git tha spindles, all the brake components, the swing arms and ball joints. RIGHT???

I'll git it all streight ..... eventually.

Thanks yet again for yalls giving of your time and willingness to share your knowledge.

Robert

One more thing. Just curious to know if any say mid 70s AMC parts are actually Mopar? Motors, trans, rear ends, brakes, , , , , anything???
 
well, that bar diameter isnt in any of mp books, you have any references I can refer to other than mopar performance past 18 years chassis manuals dg?
 
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