Police HD K-Frame reference pictures

[mattechperf]

I had my K-frame chemical dipped and took a bunch of pictures of it before I paint it. I hope these can be some good reference pictures for others to find useful.
I see what must be a lot of extra welding and bracing that I imagine wasn't on the standard vehicles.
If anyone has any thoughts on added welding, bracing, gusseting, etc...I'd sure appreciate the insight.

Mad Matt
www.madmattcreations.com

 

[Oldiron440]

All k frames are prone to cracking so a thorough sand blast and inspection is called for.

 

[BudW]

I'm guessing this K is from an '88?

All k frames are prone to cracking so a thorough sand blast and inspection is called for.

I would agree with that - with used police K's being known to have been abused most of its life (in general). The taxi K's maybe not as much (and I would say that most taxi's used the police suspension.
The problem with taxi's were they had bajjillon miles on 'em before retired (or simply fell to dust/rust). I hadn't seen or heard of a F or M taxi in 30 years? now.

The next question is it's intended purpose. If you are going racing (road or drag) or something similar, then yes - the K will need to be reinforced. If a show car or daily driver, then just fix cracks when found, and modify at your discretion.

Going back to the original question. I plan on driving my cars hard and they will have heavier torsion bars/sway bar(s) (FFI's for each) and car will be backing more weight (big blocks), so I will be prepping my K's accordingly.

The items I have found (mostly when working on Tulsa police cars) were various cracks (which are repairable), weld breaks where the steering gear bracket (yellow arrow) attaches to rest of K-frame:

Also, the two upright portions (red lines) have a tendency to bow inwards (from hard landings)(red arrow), which was reinforced (green arrow) to help prevent that. I not sure how a person could reinforce this location - without taking the assembly apart and welding something inside.

the spot welds where these two seams are at:

(both front and back seams) could stand to be welded and might be were I've found the most cracks.

Also, check for rust - which I generally see most often here:

K-frame mounts and sway bar mounts. It seams these areas tend to build up dirt which retains water moisture. Typically, if no rust is found at these locations, then you generally have a good one (cracks pending).

BudW

 

[BudW]

Here are some pictures from a '84 Gran Fury police car. You will notice some differences to yours and this one has had a crack repair job on it.
Note: the arrow is facing the front of the vehicle. Also marked is if picture is taken from birds-eye view or worms-eye view.

BudW

 

[mattechperf]

Here are some pictures from a '84 Gran Fury police car. You will notice some differences to yours and this one has had a crack repair job on it.
Note: the arrow is facing the front of the vehicle. Also marked is if picture is taken from birds-eye view or worms-eye view.

BudW

BudW, thank you so much for all that info. It's exceptionally helpful and I can't tell you how much I appreciate it when others who have "been there, done that" can chime in with useful info.
So many forums are full of people who blast out opinions with no receipts to back em up.
I'm so glad too see things are different here.

 

[mattechperf]

I'm guessing this K is from an '88?

BudW

I'm guessing this K is from an '88?


I would agree with that - with used police K's being known to have been abused most of its life (in general). The taxi K's maybe not as much (and I would say that most taxi's used the police suspension.
The problem with taxi's were they had bajjillon miles on 'em before retired (or simply fell to dust/rust). I hadn't seen or heard of a F or M taxi in 30 years? now.

The next question is it's intended purpose. If you are going racing (road or drag) or something similar, then yes - the K will need to be reinforced. If a show car or daily driver, then just fix cracks when found, and modify at your discretion.

Going back to the original question. I plan on driving my cars hard and they will have heavier torsion bars/sway bar(s) (FFI's for each) and car will be backing more weight (big blocks), so I will be prepping my K's accordingly.

The items I have found (mostly when working on Tulsa police cars) were various cracks (which are repairable), weld breaks where the steering gear bracket (yellow arrow) attaches to rest of K-frame:
View attachment 46177
Also, the two upright portions (red lines) have a tendency to bow inwards (from hard landings)(red arrow), which was reinforced (green arrow) to help prevent that. I not sure how a person could reinforce this location - without taking the assembly apart and welding something inside.

BudW

And yes, this is an 88 Gran Fury. Former City of Mesa, AZ police car.
Regarding added reinforcement to the inner part of the upper A-arm support (green arrow), I wonder if an addition, horizontal brace/mount could be made to go between the frame rail and the just above the welded/reinforced area. I would probably need to be careful in making it attach with neutral tension to the components as to not pull the A-arms inward.

Perhaps a long, threaded stud could be put in place of the upper two arm mounting plate that would preload against the frame rail. But, I'm probably overthinkin it.

 

[BudW]

I forgot to mention this.
My family has been involved in (local/small time) stock car racing and sprint car racing. If you perform much welding on a frame or chassis, we always took the frame (or componenet) to a shop to get it stress relieved afterwards. You can't take a car chassis, but something like a control arm or K-frame (or sprint car tube chassis, etc.) you can. It will prevent future cracks after welding, for welding does something to the metal during the welding process (one of those terms that fell out of brain a few years back).

I plan on getting my lower control arms and K-frames reinforced before paint.

BudW

 

[BudW]

Perhaps a long, threaded stud could be put in place of the upper two arm mounting plate that would preload against the frame rail. But, I'm probably overthinkin it.

You might be able to - but those bolts are T-shaped - so they can be tightened/loosened (or replaced if damaged). I suspect having a little "give" to K-frame might be helpful long term - if you had to jump train tracks and landed hard (typical police chases).
Those T-bolts came on FMJ, Dakota and (early) Durango only and are not easy to find.
BudW

 

[mattechperf]

You might be able to - but those bolts are T-shaped - so they can be tightened/loosened (or replaced if damaged). I suspect having a little "give" to K-frame might be helpful long term - if you had to jump train tracks and landed hard (typical police chases).
Those T-bolts came on FMJ, Dakota and (early) Durango only and are not easy to find.
BudW

I was thinking of the horizontal bolts that hold the A-arm mounting plate to the K-frame. Specifically the upper two bolts. I thought by having a stud thread all the way through, I can preload the whole assembly against the frame rail and then tighten down a nut to hold the plate. Kinda like preloading a bearing cap on an aluminum differential cover. .
However, I see your point of wanting "some" give in the setup.

 

[dm330]

Going back to the original question. I plan on driving my cars hard and they will have heavier torsion bars/sway bar(s) (FFI's for each) and car will be backing more weight (big blocks), so I will be prepping my K's accordingly

Bud, were you one of the ones able to get the torsion bars from FFI? Last year I placed my order and they were 6 years behind at the time. A couple months ago they said they had to temporarily stop production and were still 4 years behind on orders.

 

[XfbodyX]

Firm feel used to have a pic of there reinforced K they sold, it was ok for a guide to where to strengthen. But really anyone with a few years of fab work under them can look at the K and easily consider the stressors and add material or more welds to strengthen.

Ive not seen it posted yet but you might consider a two part skid plated on the very bottom of the K that outlines both in front and back of the "slot" the front sway bar sits in. Ive one rig that was raced since new and I put two spools of mig wire in it, worst I ever seen, actual rips in the metal so I will replace at some point. I just used 3/16 or 1/4 inch plate and formed it in so it looks like it came with it/part of it.

But really its just common sense from a fab standpoint. If you look at pre production vids of the front end in testing the K flexes itself which to me sucks.

 

[BudW]

Bud, were you one of the ones able to get the torsion bars from FFI?

Not tried, yet.

I need two pair. At $795 for a pair (or 1,600 for two pair), I wanted to have my $$ saved up, first.

 

[XfbodyX]

Dont know that anyone here has tried it but a skilled metallurgist with a heat treating oven can bring back old bars to even a stiffer rate without adding to the brittleness on the bars. But so far it works. Somehow we got into the habbit of either worn bars or just trying to be cool lowereing the front ends of our f-s (probably others) but that was not the intent of he design. People with correct ride height on a f these days seem to get grief for the proper high sitting front ends.

 

[M_Body_Coupe]

Not tried, yet.

I need two pair. At $795 for a pair (or 1,600 for two pair), I wanted to have my $$ saved up, first.

I've had my name on that darn "waiting list" for as long as I can remember.

Still reach out to Mike (I belive if recall correctly) once a year inquiring with: "hey, is Santa coming to visit me this year???"

 

[BudW]

a skilled metallurgist with a heat treating oven can bring back old bars to even a stiffer rate without adding to the brittleness on the bars.

I have heard that before. Metallurgy is not a topic I know much about but heat treating can do a lot of different things - depending on how it is applied.
That said, it is not "logical' that you can make a stiffer bar using the same thickness of material - but it can happen.


I want new torsion bars - but not keen of spending that much money for a bar that is very stiff.
My main item is getting new bars is partially for the new bushings - for I'd rather pay someone for new parts and to do the work for me, than tackling replacing worn and rusty old bushings (not a fun job). Also, I do want "more than stock" for a bar for upcoming big block's (both torsion and sway) - but also don't want a kidney killing ride.

My thoughts are why bars are slow to market is them trying to make new bushings - but honestly, I've no clue why the delay. Maybe I do need to call and place an order - if it will help getting 'em made.
BudW

 

[XfbodyX]

Ahh, pick didnt load right... let me re edit.

 

[BudW]

People with correct ride height on a f these days seem to get grief for the proper high sitting front ends.

I thought I was the only one with that opinion.
It is known that old springs (coil, leaf and torsion) do sag in time - so an un-touched suspension does need a bit more height in front, due to sag. But, full ride height does seam a bit "too high" in front, even with new or re-arched rear springs.
BudW