[leldai73]

i am in the process of swapping a 9 inch into my 1984 Monte Carlo and am running into some problems, I know very little suspension tech...so im pretty sure its time i come to the message board and ask for your help
the Monte Carlo uses what i can best describe as a triangulated 4 link.
I spent all day yesterday making a jig to transfer the exact location of the control arm mounting brackets. I have built the jig keeping the center line of the housings the same, there was a difference in the diameter of the tubes, i made cradles to hold the 9 inch in the jig, and then made spacers at half the difference of the tubes and placed them under the stock axle while it was in the jig. i then set the angle of the front of the yolk to exactly 90 and built four arms attached to the control arm mounts and the base of the jig. after all of this careful planning...nothing fits .
the difference in the height of the center area of the housings was much greater than the difference in the diameter of the tubes. so its not possible to weld the upper control arm mounts where they belong in relation to the center line of the axle. my question is. can i move these mounts up 2 to 3 inches without causing binding in the suspension. or do i have any better options that any one can see and i cant?
thank you in advance for ANY input on the subject, as im pretty much making this all up as i go along.

[cboy]

Not that I'd be of much help, but I'm having a hard time visualizing the exact problem. Is there any way you can get under there to get some decent pictures of what you are trying to do and the obstacles you are running into? Might help the REAL suspension guru's give you some guidance.

[Koolaid]

I think what he is getting at is that the 9" center section is physically taller then a 10 bolt - thus you can not mount your upper links in the same exact spot as you would be inside the housing!

I don't have an answer for a street car - on my stock car they are raised, but we are also trying to do something different with bar angles and pinion angle and what not.

[joe_padavano]

Originally Posted by leldai73

...the difference in the height of the center area of the housings was much greater than the difference in the diameter of the tubes. so its not possible to weld the upper control arm mounts where they belong in relation to the center line of the axle. my question is. can i move these mounts up 2 to 3 inches without causing binding in the suspension. or do i have any better options that any one can see and i cant?
thank you in advance for ANY input on the subject, as im pretty much making this all up as i go along.

Well, many sources sell "hop stop" bars that effectively relocate the upper control arms up about 3" on the stock GM axles to improve traction. Assuming the taller housing or control arms don't hit the floorboard, the relocation is probably OK. The bigger problem is the binding of the control arms. The stock four link actually twists the control arms a little during suspension movement. This relocation may make that worse. The best thing to do is to get aftermarket upper arms that have a metal rod end (ball joint) at one end of the arm to avoid any binding.

[leldai73]

Ive decided to move the housing down about a half inch in the jig, putting the lower control arm mounts closer to the bottom, and raise the top mounts 1.5 inches, this will give me the clearance i need and hopefully not change things enough to noticeably affect the cars handling. i'll let everyone know how it works out.

[leldai73]

ive come to stand still, had to make new upper mounts, as the stock mounts are cast, and i dont have an offset boring head, or an adjustable reamer and proper size brill bit that large to generate the proper sized hole.

[techinspector1]

I guess I don't understand being stumped because you don't have fancy equipment. I've built cars for 50 years with little more than hand tools. It's amazing what you can do with a torch and a good set of files.

[Chopt 48]

Leladi73 it sounds like you know how to do the job the right way the first time.
I'd sure like to see some photos of this project it sounds interesting.

[leldai73]

tech inspector, my torch and files (well, angle grinder) have taken me as far as i can go with the brackets. i cut them out of some 3/8 plate and shaped the outside.

now i need the offset boring head to make a very accurate, very odd sized hole to press fit the new bushings. the hole needs to consistently be somewhere from .002 to .004 smaller than the od of the bushing which is 1.855, if you can do that with a torch and a set of files, i would like to shake your hand.

i'll try to post some pictures...i havent posted any yet because i have dial up and its like pulling teeth to get it to transfer any thing large.

[leldai73]

finaly found someone willing to let me use their offset boring head and after about 2 hours of machining last night my brackets are ready, welding them on tonight.

[leldai73]

axle fits fine, once the sway bar was removed. bushings fit good, seems to move up and down fine...but the sway bar doesn't fit. the problem is the center of housing is not centered. the rear end was cut to put the pinion on center. which we had considered more important than having the center of the housing on center..so far its looking like we were wrong. after the problems with the upper mounts and now the sway bar i think if i do another one the center of the housing will be the center...period. and i can just let the u joints work a little harder.

so, my newest question in this long list is...can i cut and weld a sway bar, or is it...for lack of a better term...some type of spring steel. if it cant be welded can it be heated re-bent and re-tempered. im thinking that its some type of hardened steel, but don't know for sure, no Rockwell tester in the shop...man do i miss school where i could use all these fancy things.

once more, i appreciate any insight on the subject. thank you in advance.

[Chopt 48]

i believe the sway bar is some type of spring steel. I don't think I would be cutting and welding on it.

We had one snap on the 79 Cad Deville we had, I still don't know what my wife did to cause that.

On the rear end with the offset pinion. Ford has been running that style since 1957 with the housing centered and the drive shaft running at a slight angle and it only seems to be an issue with Chevy guys or people who think the drive shaft has to run in a straight and true line or something is wrong.

Before anyone flys off the handle about that comment. I don't own any Fords
The driveway is filled with Chev, GMC Dodge and Mazda.

It looks like you will end up doing a new housing to make things work properly.

[leldai73]

and take the easy way out, never.

[leldai73]

Ive been assured by a one of my professors from college, the guy knows his stuff, builds race cars, narrows housing, sets up suspension and etc. that i can bend the sway bar, so thats what im going to do. im left with no other option really. i'm going to try to bend it without heat, but, if it turns out heat is necessary, its getting heated and i'll deal with the ramifications later.

[leldai73]

well, i just took the car out for a spin for the first time in a month or so...modified control arm mounting points and custom bent sway bar seem to work fine. no wheel hope at all and it seems to corner much better with the new urethane bushing and boxed lower arms. there is a strange vibration i think it comes from the break drums that i had to do a little clearanceing on. just removed some of the huge cooling fins. i hope that can be fixed by getting to a mill or lathe and cleaning up what i did with the grinder.