What do you guys make of this?



I just finished the install of a Borgeson power steering box in the car. This is the second version of the box with the large sector shaft. There is a considerable amount flex in the case when running the tires from side to side. You could still see a small amount of flex in the case even with the front end in the air.

I know the first version of the boxes had issues with not mounting flush to the K-frame, but this is right up against at all three mounting points with the bolts tight.

I haven't taken the car out for a drive yet; I discovered this when checking for leaks.
Front tires are Nitto 555, 255-45-18. PS pump valve is shimmed to 850 PSI.

How's the K-frame? Are there any hidden cracks or breaks you don't know of? Is the K-frame reinforced?

I agree with above. I'd guess you have an issue with the k frame/steering box mount or bolts are loose etc...?

From what I remember, this is a common problem in the mopar world. Firm Feel sells a sector support kit that was used to help stop the K-frame flex when steering. I believe it's caused due to the long distance from the steering box to the turning linkages. Turning the tire causes a large moment arm on the steering box that the K-frame can't handle. From what I can tell it was just a bearing that slid onto the steering side of the pitman bolt with a bracket that connected to the K-frame. That bracket coinciding with the bearing. Since the bracket is now constrained underneath the K-frame and the bearing is taking some of the radial loads from the pitman arm, the steering box wouldn't translate as much while turning.

Call Firm Feel and see what he can do; however, I'm not sure how this would adapt to the Borgeson box. You may have to make up your own.

http://firmfeel.com/a_body_mopar_sector_support_kit.html

http://firmfeel.com/img/old/Primesteer.pdf

I would not be happy with that amount movement. And if with tires lifted you have similar but less movement, pretty much points to a K frame issue, IMO. You didn't by chance observe the same test with the OEm box, did you?

I'd say with the tires lifted and some amount at all of the motion occurred that bolts were loose. Virtually no resistance force with the front off the ground.

Damon

The mounts for the steering box have been known to be a weak link. They were designed for use with skinny bias ply tires on a car was that was considered to be used and scrapped by 100,000 miles or less. Add 40 years of age, heating and cooling cycles, twice the engine power, twice the tire width and.....
I welded gussets in my K member to add rigidity to the steering box mounting pad. No problems on my end. Firm Feel Stage 3, 275-40 front tires and all is well.

I already noticed an improvement in steering feel after I welded this simple plate to the steeringbox mount and lower K-member lip, shown below.
I'm sure more inforcement in that area will help.

My box only moves like that when the bolts back out. Locktite FTW.

I would pull the box and weld in gussets to the K. More than likely there's an actual failure point somewhere.

Yeah, sure enough the K is flexing; the box is perfectly rigid. My Dad has an 80 Diplomat that we did this install on too and it doesn't flex at all even though his Dip uses the same K as my 87. There is a difference though...



Here is a shot of the mount from underneath on my car. My father's car has no space in between the box mount and the K like mine does. Unfortunately Firm Feel doesn't have a support kit for M body cars; I guess I'm going to have to weld in some kind of a patch to shore this section up.

Thanks for the input guys.

Make patterns out of cardboard, then trace them onto .120 wall or 1/8" steel plate.
Weld into place.
Turn corners faster.
Impress chicks.
Or not.

And as an additional point, this new box has a faster(?) turn ratio, which also means if steering wheel is turned equally as fast as before, the forces are now greater, instigating greater flex on the mounts, every time.

I would do the reinforcement and add the Firm Feel sector support kit.

hmmm I never locktite mine in. Is the bolts backing out a common occurance? I welded and gusseted my kframe should I be alright?

I was down by Charlotte at the NASCAR All Star Race and the attached photo is how they support the sector, which is very similar to how Firm Feel does it, they just have it welded in.

I have the firm feel sector shaft support with a Borgeson box, works fine. My K-frame has all the gaps around the box mount filled with plates and welded.

I like that setup, but how much does that bearing sit below the K-member.

Could you take a board to show against the K-member extending to the bottom of that bearing assy. like this:

don't want anything to catch if this happens.

OK... did it with a 3' level. The part of the nut that sticks out past the pillow block bearing is about 1/2" lower than the oil pan, but it sticks out about 1" past the bearing. Looks like I could trim the part that sticks out past the bearing with no loss in function and then it would not be lower than the oil pan.

So you'd cut it off flush with the aluminum collar that is pictured with that set screw with blue paint around it?

Then, that would make it flush with the bottom of K-member?