You supplied the part number for the "brake booster" and NOT the master and that particular booster fit '85 - '89. Do you know if your front calipers are dual or single piston units? That would ID the front as to whether '87 or earlier OR '88 and later.

For a coil-over for your particular application I wasn't thinking of a Corvette application "off the shelf". There are much better applications that could be used for your Buick. There are applications with much larger piston rods and perhaps your upper mount won't interfere with a heavier install.

On your lower control arm, does the shock bolt directly to the lower control arm OR to a plate that bolts to the control arm? Your snapshot hints earlier but it's not a very clear image so I thought it easier to ask.

Judging from your snapshot of the master your brake master is either '84 or '85 NOT '86 or '87 OR '88 to '91. The casting number of the master which would ID it is on the bottom. A mirror would work and I could ID it from there.

So, single or dual piston calipers, how does the shock mount to the LCA OR a casting number from the bottom of the master and I can ID the suspension.

This is '87 or earlier suspension:



What is the installed height of your current shock? Center of t-bar to top center at frame bracket. Did you duplicate the dimension from the original frame?

 

WVZR-1

You have given me some great info.

* The T-bar does mount to a bolted on A-arm plate, if I recall correct, but will take a peek. I do know that the lower plate has snap-on spring steel fasteners that the bolts connect to that serve as nuts.

* The shock length at RIDE height is 12-1/2". I did duplicate the shock mount position and measurements with in 1/4" at most.

YOU, have been very helpful, and I THANK YOU so much, I will get back with ya.....

Bride and I are taking two grand children to the Carmel Indiana car/art show today, 'PRAY' it doesn't rain, hehehe.

Dale in Indy

* I will use a mirror to check under the master cylinder unit for ID info.

 

I believe we can determine the year of the suspension a couple other ways if you're interested. The calipers attach to the front spindles with M12 hardware in '84, in '85+ cars that was changed to M14 hardware. In '84 and '85 there was no ABS and in '86 ABS was added. With that said with your master cylinder reservoir arrangement I believe your front is likely '85. If there's a provision for an ABS sensor then I'm wrong but I'm fairly confident. The ABS sensor location would be just above the steering arm and would be a round bore with provisions for two threaded fasteners.

All of this is assuming all of the front including the brake and master are from the same donor.

Do you have any issues with wheel/tire interference if the steering is turned to lock in either direction?

 

WVZR-1

Ok, here are some shots JUST taken........

Using a mirror like you suggested, I believe these are the numbers on the bottom of the twin cylinder. ( OC420 212K )



So much THANK YOU is what I want to convey...

More pic's in a few.

Dale in Indy

 

More,,,,,, first I can say 100% sure Master cylinder assembly DID come from the clip I purchased/used.

Two of the pic's show the clip I purchased for $500.00. Note you can see the steering column, brake pedal assembly from the dash side. The other pic doesn't show the master assembly, but I know it came from this clip. I was able to bolt the brake pedal to the inside of the firewall, and resembled the master unit to such. Worked very well.

I didn't get to check the bolt size of bolts holding caliper on.



Dale in Indy

 

The casting number of your spindle hints that it's an '84 part and likely has M12 hardware for the caliper. I can't explain the booster assembly number but regardless you know which suspension package you have to work with. Maybe late '84 cars got the newer PBR assembly.

 

WVZR - 1,

NO, the wheels don't rub the fenders/wells. I does have a very long turning radius, but with 142" WB, seems natural.

I do want to mention, that I did shorten the ROD & YOKE assemblies that go from lower A-arm to the actual SWAY BAR ends, with the mounting of the sway bar brackets to MY frame, it required such. I have considered removing the sway bar to see it that would help the jarring ride. I understand it shouldn't play into it, but again, I'M NOT AN ENGINEER.

Comments are MOST WELCOME.

Dale in Indy

P.S. IN POST #24, 3rd. pic. you can see the sway bar rod/yoke assembly. It may be tilting outward a bit since it is shorter than originals. With the shocks off the car, the front does move smooth and far when jumping on the bumper, so doubt the sway bar is hurting the ride.

 

I did the master cylinder and the casting # K212-024C (I used your information and just converted it to what I'm familiar with and you were using a mirror) was used for several versions so that's of little value.

This is how the spring rates work for early cars, '84 were certainly the stiffest, the '84 base spring became the HD or Z51 spring in '85 - '87 cars and there were newer springs for the base vehicles. The springs were coded on the top on one end or the other and if you were interested I believe you could remove the shock and the mounting plate to see the label/tag if it were still there.

Here's all of the front spring codes I'm familiar with for the early cars through '87:



Your problem with coil-overs could likely be that you used the shock tower on the clip as a model and made your upper mount the same or similar width. For a coil-over the tower needs to be something very close to 3 1/2" wide to accommodate the hat and spring diameter. There are smaller available but they're more difficult to find and work with. Maybe you could measure your tower width on the upper mount.

Search eBay for "FHU spring" and there's a snapshot of the label you could expect to see if you wanted to look at yours. It would be considerable aggravation to just try a later softer spring knowing that your considerably over-weight as it is. A used spring to just test it could maybe work and then if it accomplished what you wanted there's possible choices. The spring label is the last snapshot. You don't want this spring, I just used it as an example for the "label".

Did you ever have it on the road before you did the "lowering wedge" modification? Was it actually to high? Back to standard height with no modifications maybe a solution?

 

I agree that the HD spring if that's what's in the car now, MAY be just what I need.

As stated, jumping on the bumper does produce a smooth nice movement, and with what feels like what I should like.

I do want to know exactly what spring I have, so will take a peek.

I would remake the shock tower/bracket if I do go the coil-over route. I would probably use 3/6" or 1/4" material, and spread such out for spring clearance.

Will look for spring #/ID in the next couple days.

Thank You so very much. I feel I am making good progress, thinking after I determine the spring I have that I will seek an adjustable shock that allows me to back off the compression a lot. I want the suspension to WORK. I really believe the shocks that were in it are too STIFF, and didn't allow much movement. I am going to pull the lowering wedge, it only lowered the car approx. 1/2" - 3/4".

It would be interesting to know what is the length of the shocks at RIDE HEIGHT of a C4 stock Vette, mine is 12-1/2"

I can't say with 100% sureness how it rode B4 the wedge was installed, I'm thinking it was a tad less JARRING......

Dale in Indy

 

Just keep in mind that the C4 Transverse Mono Leaf Spring suspension, was not designed to ride like a Cadillac.....

 

Would some of that be SHORTER A-ARMS?

Dale in Indy