Dart 72 vs 73 susp dilemma

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Boduke

Boduke

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Hey all,

FNG here. Thanks for having me, glad to be here.

Have an interesting scenario here and could use some help.

I have a 72 dodge dart swinger coupe - manual steering manual & front disc brakes..

Car was originally a slant 225 (per fender tag) and before I got it, someone converted to 318 from a 73 (I have checked the block to confirm)

When they did the swap, they did the k member and motor from the 73. (and maybe the brakes)

Oh and wanted to mention also, the brakes are a slide type caliper if that helps..

Now my car is getting older and could use a front end rebuild that I want to do myself then roll to the alignment shop

I want to do everything at once, i.e. control arm bush, BJ’s, Idler/pit, tie rods etc, etc

My confusion lies within the swap. First off, I am under the assumption that you couldn’t get disc brakes until 73 so was that swapped in? .

secondly, it is my assumption that most of the front end stuff except maybe shocks are different between the years.

I don’t know dodge so when doing a k member and or brake swap (I cant confirm that the discs were swapped), would you typically convert all the front end to match the K member?

Or… Would you retain the 72 stuff and just swap motor and/or brakes

Or.. worst case scenario, could my car be a hodge podge of mixed year parts?

Thoughts, suggestions, insight or direction appreciated?
 
If I say I hate the u3 and later K member, I’d be lying but I don’t know what word is better. I hate it. I hate spool mounts.

Ok, got that rant off my chest. Yes, you could get disc brakes in 72, but I’m not sure you could with a /6. Maybe if it was ordered that way, or maybe you could. The fender tag will tell you the story.

As for the brakes...the 73 single piston caliper brakes IMO are a downgrade from the 72 four piston calipers. I’ve had both and I have the 73 stuff now and I prefer the 72 stuff.

All your performance brakes are multiple piston calipers. The K-H four piston calipers get a ton of hate, like the 67-72 K members, but that’s what I like. I’m converting my 73 to a 67-72 K member, but I, keeping the 73 brakes because I don’t want the small bolt circle.

What you have is fine, most of the stuff interchanges. If you do have the spool mount K member just make sure you order the 73 parts to rebuild the front end.
 
one thing to do for sure if not already there change the tie rods and adjusting sleeves over to the 11/16 as apposed to the 9/16 can be used from different models there are several kits out there that have everything needed pick what you want in brand and price sometimes you can piece mill for less $$ presume who ever changed over to large upper ball joints
 
Boduke said:
Hey all,
FNG here. Thanks for having me, glad to be here.Have an interesting scenario here and could use some help.I have a 72 dodge dart swinger coupe - manual steering manual & front disc brakes..Car was originally a slant 225 (per fender tag) and before I got it, someone converted to 318 from a 73 (I have checked the block to confirm)When they did the swap, they did the k member and motor from the 73. (and maybe the brakes)Oh and wanted to mention also, the brakes are a slide type caliper if that helps..Now my car is getting older and could use a front end rebuild that I want to do myself then roll to the alignment shop I want to do everything at once, i.e. control arm bush, BJ’s, Idler/pit, tie rods etc, etc
My confusion lies within the swap. First off, I am under the assumption that you couldn’t get disc brakes until 73 so was that swapped in? .
secondly, it is my assumption that most of the front end stuff except maybe shocks are different between the years.
I don’t know dodge so when doing a k member and or brake swap (I cant confirm that the discs were swapped), would you typically convert all the front end to match the K member?
Or… Would you retain the 72 stuff and just swap motor and/or brakes
Or.. worst case scenario, could my car be a hodge podge of mixed year parts?
Thoughts, suggestions, insight or direction appreciated?
Click to expand...

Hello Boduke,
First Welcome to the FABO family.
I am not the expert on your questions but knowing from past history when people do swaps not always are all the parts from same make and model.
I have a customer's car in the shop (73) with a 71 K member and disk setup (73).
As a suggestion if you can add some pictures of the components that you have it will help the knowledgeable fellow FABO members to provide the most acurate infomation to complete your task at hand.
Hope this helps in some way.
Stay Safe.
Happy Mopar :)
Arron.
 
Hey guys. Thanks for the quick replies..

No offense but now I have more questions than I did when I started

Define. Spool mount, small bolt circle, k-h, u3?

Wtf does all that mean? J

So I guess I have to check the calipers for 2 piston vs 1 and that will tell me the year? (assuming 2 piston is 72 and one piston 73)

And the tie rod diameter bigger is better.

All the other stuff im on my own. Prob hodge podge is what I gather.

So, order all the **** for both years and return what doesn’t fit sounds like the new plan.
 
And ill get pictures and report back. Thanks again. Sorry for my ignorance
 
Boduke said:
And ill get pictures and report back. Thanks again. Sorry for my ignorance
Click to expand...

Hello Boduke,
Nothing to be sorry about.
We were all new at some point and look forward to passing on the information that all our fellow FABO members can provide.
If you use the "search" box on the main page and enter things like "Spool Mount" you can also do self education on names of parts that may be unfamiliar to you.
Stay Safe..
Happy Mopar :)
Arron.
 
Boduke said:
Oh and wanted to mention also, the brakes are a slide type caliper if that helps..

I want to do everything at once, i.e. control arm bush, BJ’s, Idler/pit, tie rods etc, etc

My confusion lies within the swap. First off, I am under the assumption that you couldn’t get disc brakes until 73 so was that swapped in? .
Click to expand...

If you have slider calipers, sounds like the whole K frame and suspension was swapped. If you have spool-type engine mounts and a 4.5" bolt circle, that would support that theory.

Disc brakes were available in '66. Up to 72, they were a fixed caliper with 4 pistons make by Kelsey-Hayes.
 
4 opposed pistons, not 2 Pic - 66 to 72 caliper.

brake-caliper-front-1967-68-cadillac-eldorado-w-kelsey-hayes-4-piston-ce10802.jpg


Welcome to the forum, BTW.
 
Can ya get some oi tires of what you have? K-frame. Center link, idler/pitman arms brakes. Would make helping out a lot easier.
 
Ok.. Good info
Here. I have single piston calipers and no B11 code on tag so brakes are 73. And mounts are spool type.thanks kendog and demonic for making that kindergarden easy. Bolt pattern not sure
 
Hi Boduke and welcome to the forum. You're def in the right place to ask questions. Lots of very knowledgable guys...and gals here.
What's your general location in Mass.? I'm on the North shore near the New Hampshire Border.
 
It definitely sounds like your 72 has been swapped over to 73-76 front suspension. No need to order both early and late parts. Your car probably had 4 wheel drum brakes when new as they were standard and yes you could order discs on a 6 cylinder car. I personally reuse ball joints, tie rod ends, etc if they are good and the seals are not torn. Original Mopar parts were good, better than the typical Chinese crap. Definitely plan on replacing the Lower Control Arm bushings as most times they are deteriorated originals and have not been touched. Pictures would help a lot! I put a 73 K in my 68 with brakes etc. because I thought at the time I'd be putting a big block in it with spool mounts.

No need to convert back to 4 piston Kelsey Hayes brakes. Going back to SBP would require different wheels.

Whichever brakes were on it when new, your 1972 had the small bolt pattern. That's 5 bolts on a 4" diameter bolt circle and 7/16" studs. 1973 and newer disc brakes went to the more common 5 on 4.5" diameter with 1/2" studs. You should check the rear bolt pattern while you are at it. Could still be SBP (small bolt pattern). Wheel selection is not as good with SBP.
 
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Take some pictures and post them and we'll be able to tell you what you have. The 1973 and newer stuff is better than the older stuff so the more of it you have the better. I converted my '72 Duster all over to the '73+ stuff since it works better. The anti-sway bar is tucked inside the K frame where it should be, the late model knuckle uses a larger wheel bearing, the late model brakes are a better design, the spool mount is a better design than the pad mount, etc.
 
yellow rose said:
If I say I hate the u3 and later K member, I’d be lying but I don’t know what word is better. I hate it. I hate spool mounts.

Ok, got that rant off my chest. Yes, you could get disc brakes in 72, but I’m not sure you could with a /6. Maybe if it was ordered that way, or maybe you could. The fender tag will tell you the story.

As for the brakes...the 73 single piston caliper brakes IMO are a downgrade from the 72 four piston calipers. I’ve had both and I have the 73 stuff now and I prefer the 72 stuff.

All your performance brakes are multiple piston calipers. The K-H four piston calipers get a ton of hate, like the 67-72 K members, but that’s what I like. I’m converting my 73 to a 67-72 K member, but I, keeping the 73 brakes because I don’t want the small bolt circle.

What you have is fine, most of the stuff interchanges. If you do have the spool mount K member just make sure you order the 73 parts to rebuild the front end.
Click to expand...

It's like backward world in here. The spool mounts are better. The don't separate like the original mounts and they positively control the engine from moving forward and back. I mean, you can not like them if you want, but performance-wise they're the superior mount. And like AndyF said the sway bar is tucked up inside the K, better routing and more ground clearance.

You could order disk brakes on /6 cars. The single piston slider calipers were an upgrade over the 4 piston KH calipers, not a downgrade. You can argue that a fixed caliper is better than a slider in general, or that in general multi-piston calipers are better, but with leaky seals and parts that are very difficult to find the KH brakes are not better now. The 73+ single piston sliders are simple, work great, and take a lot more abuse. Just because the Kh brakes were multi-piston does not make them better, they're different than modern multi-piston calipers. Just because multi-piston calipers are used in higher performance applications does not mean that EVERY multi-piston caliper is better.

If someone has a full KH disk set up on their car already that's one thing, but the OP already has a single piston slider set up. Tracking down all the parts for the KH disks would be a pain, not to mention expensive. And then he'd have to convert it back to small upper ball joints and figure out the SBP vs BBP thing by either doing the mustang rotor conversion or buying new wheels. He already has the better set up.

dodge71demon said:
And the tie rod diameter bigger is better. bigger is always better
Click to expand...

Nope. Not true. The tie rod diameters were the same for all A-bodies, 9/16". C-bodies ran 11/16" tie rods, and while that used to be a nice way to upgrade the strength it's unnecessary now. The weak part is not the 9/16" tie rod end, it's the spit tube adjuster. Now you can buy tubular adjusters that aren't split, which eliminates the flex in the tie rod adjuster. So you can stay with 9/16" ends

AndyF said:
Take some pictures and post them and we'll be able to tell you what you have. The 1973 and newer stuff is better than the older stuff so the more of it you have the better. I converted my '72 Duster all over to the '73+ stuff since it works better. The anti-sway bar is tucked inside the K frame where it should be, the late model knuckle uses a larger wheel bearing, the late model brakes are a better design, the spool mount is a better design than the pad mount, etc.
Click to expand...

Exactly. Everyone swaps their cars to the 73+ parts- BBP, large ball joints, larger wheel bearings, better brakes, better mounts, better sway bar set up, etc, etc.
 
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72bluNblu said:
It's like backward world in here. The spool mounts are better. The don't separate like the original mounts and they positively control the engine from moving forward and back. I mean, you can not like them if you want, but performance-wise they're the superior mount. And like AndyF said the sway bar is tucked up inside the K, better routing and more ground clearance.

You could order disk brakes on /6 cars. The single piston slider calipers were an upgrade over the 4 piston KH calipers, not a downgrade. You can argue that a fixed caliper is better than a slider in general, or that in general multi-piston calipers are better, but with leaky seals and parts that are very difficult to find the KH brakes are not better now. The 73+ single piston sliders are simple, work great, and take a lot more abuse. Just because the Kh brakes were multi-piston does not make them better, they're different than modern multi-piston calipers. Just because multi-piston calipers are used in higher performance applications does not mean that EVERY multi-piston caliper is better.

If someone has a full KH disk set up on their car already that's one thing, but the OP already has a single piston slider set up. Tracking down all the parts for the KH disks would be a pain, not to mention expensive. And then he'd have to convert it back to small upper ball joints and figure out the SBP vs BBP thing by either doing the mustang rotor conversion or buying new wheels. He already has the better set up.



Nope. Not true. The tie rod diameters were the same for all A-bodies, 9/16". C-bodies ran 11/16" tie rods, and while that used to be a nice way to upgrade the strength it's unnecessary now. The weak part is not the 9/16" tie rod end, it's the spit tube adjuster. Now you can buy tubular adjusters that aren't split, which eliminates the flex in the tie rod adjuster. So you can stay with 9/16" ends



Exactly. Everyone swaps their cars to the 73+ parts- BBP, large ball joints, larger wheel bearings, better brakes, better mounts, better sway bar set up, etc, etc.
Click to expand...


We have to agree to disagree. The spool mounts move all over the place. You can feel it when you drive them. I can at least buy solid mounts for the early K member. And, I’ve seen the spool mount mounts be off and there isn’t anything you can do about it. With the early K, you can move the engine in the mounts a bit if you need some room for headers.

The 73 single piston caliper isn’t nearly as good as any opposed piston caliper. That’s why all aftermarket brakes worth a damn are opposed piston calipers.

Like everything else, the spool mounts and single piston calipers were changes made for money. It’s not the mounts fault if the stooges who drive these cars don’t replace the engine mounts every 100k or so.

My first car was a 72 Demon. Has the K-H brakes. Didn’t stop worth a ****. Rebuilt the calipers. Still didn’t stop. Everyone said go to the 73 stuff and don’t look back. Except being young and dumb, I didn’t replace the mounts in time and not only lost a street race because of separating a mount, I broke my shroud.

So I just bought steel mounts. I knew backing out of the driveway how much better the steel mounts are. So...to pick up the story I got on the phone and called some people. The answer wasn’t change the stuff over to 73 stuff. The fix was to convert it over to manual brakes. My shop teacher lost his mind and wouldn’t let me do the work in shop class without my parents signing a waiver that if I crashed the car or something went sideways, the school and himself wouldn’t be liable.

I had him drive the car and he agreed it didn’t stop. So I converted it over to manual brakes and it was a WORLD of difference. Not even close. The junk 73 I have now had power brakes. It now has manual brakes, and even my wife likes how it stops.


So yes, I hate spool mounts and the sloppy drive they give, and I’ll take opposed piston calipers over a single piston caliper any day of the week. With the exception of using the small bolt pattern.

In fact, I have a line on an early K member and I will get it and get rid of the crappy spool mounts. I can’t wait. Should have done it when I had the engine out in 2014. But I listened to all the gurus who claimed a Poly bushing was the schizznizzle. It ain’t. It moves around like anything else that isn’t solid.
 
o.k just measured the bolt pattern front and rear.. 5x4.5.

so. To recap. 72 model year (confirmed with vin and fender tag and they don’t look swapped) 73 k-member with 73 single piston brakes with spool type mounts

what probably happened. Like Demonic stated here .. is that someone did full front end and rear axle swap from a good running 73 to my 1972.

Im going to assume order all my parts for a 1973 as far as suspension stuff. This was a massive help guys.

I will post pics when I pull it apart. Car is running and driving but was just looking to upgrade front end stuff as most of the boots are hammered and grease nipples shot.

Thanks everyone for all the info. This has been very informative for me. I learned a lot

Thank you to everyone that posted

72nublu & demonic – for laying it out for me.

kendog, andyf, kosmickuda, 67dartgto – see you up on north shore guy’,

abodyjoe, dodge71demon, 383 scamp – see you in the six 0 three

aaron tate and yellowrose.

Really glad to have all this knowledge in one place..

And for what its worth with all my 73 stuff, the car drives amazing. Its a stock 318 driver with 2.73 gears. And i feel like a millionaire when im behind the wheel
 
Nope. Not true. The tie rod diameters were the same for all A-bodies, 9/16". C-bodies ran 11/16" tie rods, and while that used to be a nice way to upgrade the strength it's unnecessary now. The weak part is not the 9/16" tie rod end, it's the spit tube adjuster. Now you can buy tubular adjusters that aren't split, which eliminates the flex in the tie rod adjuster. So you can stay with 9/16" ends
IMO it doesn't make since to pay big $ for tubular adjusters when you can buy new 11/16 adjusters and tie rods for probably less $ and be good to go I always make this upgrade and have for many years
 
Let me try and simplify this

67 K member was 'all alone' because of a different idler arm mount

68-72 K are the same, the factory anti-sway bar IF USED goes under it, and they have the "pillow" mounts

73/ later K has spool mounts AND if equipped with a factory anti sway bar it threads INSIDE the K. The anti sway bar "tabs" on the lower control arms are different up through 72 versus 73/ later

You can use a late or early K with no other changes other than motor mounts. you can use an early anti-sway bar with the late K if you use the lower arm mounting tabs off the 72/ earlier

For the disc brake conversion you must use 73/ later upper control arms as the ball joints are larger, referring to the later single piston brakes

Many guys advocate using ?Volare? calipers as they are larger Many of us swap the spindles and calipers side for side to place the calipers "to the rear" for added anti-sway bar clearance

Steering box/ linkage: later steering boxes have a larger pitman shaft spline. The pitman arm, the center link, the idler arm, and the steering box must all fit. These items must all be off either all 72/ earlier, or all 73/ later. These pieces can be used with either drum or disk, and with either late or early K

You can tell which center link setup you have by just looking. Look and see if the studs on the pitman/ idler/ tie rods face upwards or downwards

72/ earlier has "nuts on top"

old-jpg.jpg


73/ later has "nuts on bottom"

new-jpg.jpg
 
67dart273...thanks for that last post. Clearly i have 72 pit/idle/drag as nuts on top. Here are a few photos of what i have. Upper BJ's measure about 1-7/8 wide on top if that means anything.

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so after thought. Looks like someone may have swaped knuckles side to side as my calipers are rear mount. Cant tell if volare calipers or not. Based on all the info in 67dart273's post, i have to assume that uca and upper bal joint and lower bal joints are all 73+. While Steering Box / drag arm / pit and idler arms all remaining 72 stuff. Tie rod ends are same for both years. Thank you everyone especially 67dart273. What differentiates volare calipers? Any other insight is really appreciated.
 
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