[BillyGman]

This has to do with UMI weld-in relocation brackets part # 4010 shown here...

1964-1972 GM A-Body Rear Lower Control Arm Relocation Brackets- Weld In - UMI Performance Inc.

..and UMI Rear Lower control arms part # 4023CM-B shown here...
1964-1972 GM A-Body Adjustable Rear Lower Control Arms Chromoly - UMI Performance Inc.

As in the pics the mounting holes in the relocation brackets for the lower control arms are 1/2" diameter, and the UMI mounting bolt kit (part # 4001) comes with 1/2" diameter bolts that fit nice and snug in the 1/2" bolt holes of the brackets. However, the upper holes of the brackets which are intended to bolt the brackets onto your existing lower control arm mounting brackets that are welded onto the rear end axle tubes, are 5/8" diameter, which seems like a mismatch to me since the axle tube brackets have 1/2" diameter holes.

To add a little more confusion, the suppled bolt kit which came with these UMI weld-on relocation brackets free of charge, have 7/16" diameter bolts which are supposed to be used for the 5/8" diameter bolt holes per UMI instructions. As you can see, the 7/16" mounting bolts are swimming in the bracket holes, and even the the supplied sleeves that came with these brackets have inner diameters that are adequate for 1/2" diameter bolts.

Another mystery having to do with these weld-in relocation brackets, is that they're .020" too narrow to accomodate the UMI rear lower control arms. Now I can simply take my angle grinder to the control arms to shave off .020" so that isn't a huge problem. Although I must say that I'm a little surprised about the lack of correct fitment, because otherwise, these UMI products look like nice pieces. The welds on the relocation brackets look to be top notch, and the lower control arms appear to be high quality.

Here are my two questions:

#1. Has anyone here purchased these UMI weld-on relocation brackets? Please make mention if you received the same supplied hardware with mounting bolts that were much smaller.

#2. Would you, (or did you) use these 7/16" bolts in the 5/8" mounting holes, or would you/did you just go ahead and buy a pair of 1/2" or even 5/8" bolts and use them instead? Having .188" of play between the bolt shanks and the I.D. of the mounting holes in the brackets just seems to be excessive to me, although it will be the welds that will be holding the brackets in place on the original axle tube brackets. But then why even use bolts at all if they're swimming in the mounting holes like this?? Using 1/2" bolts or maybe even 5/8" bolts in the 5/8" bolt holes seems to be a no-brainer to me, but I thought that I'd ask you guys about this first just to be sure that there isn't something obvious here that I'm overlooking.

based on what we see here in the pic below, it looks like I'll be using my angle grinder to shave about .020" or .030" off of the UMI lower control arm pivot pieces to get them to insert between the two mounting ears of the UMI relocation brackets. They're only aluminum, so it should be easy work. Not any big deal, just a little surprising that UMI brackets don't fit over UMI control arms. I guess they're not made in-house...

I'm wondering if there's a perfectly valid explanation for this since UMI has been selling these relocation brackets for years. So I would think that if this was an oversite on their part, that it would've been addressed and corrected a long time ago. I sent an e-mail along with the pics to UMI, and while I'm awaiting an answer from them, I wanted to also ask some of their other customers about this.

 

[Geo71]

Mine are the bolt on style that I was told to weld on (which I did). I don’t remember the bolt holes being like that. Also did not have to remove any material from the arms.

Will be under the car today so will look at those top bolts.

 

[Stokerboats]

I'd be speaking to Ramey before I did anything.

 

[Kirk's67SS]

I would assume they sent you the Wrong Bolts , so talk to Ramey and get the Right ones !!??

As for the " lower control arm pivot pieces to get them to insert between the two mounting ears of the UMI relocation brackets "
I would talk to Ramey about this before I did anything and see what he says
maybe you just got a off one OR they need to Retool their Measuring Machines

 

[mrpaticular]

Put mine on last year. Correct bolts and fit lower control arms with no mods.

 

[BillyGman]

Mine are the bolt on style that I was told to weld on (which I did). I don’t remember the bolt holes being like that. Also did not have to remove any material from the arms.

Will be under the car today so will look at those top bolts.

Thanks. Please let me know what you find.

I'd be speaking to Ramey before I did anything.

Who's this Ramey guy? One of their salesmen??

I would assume they sent you the Wrong Bolts , so talk to Ramey and get the Right ones !!??

Yeah you would think so, but the funny thing is that it says right in the instructions to use the 7/16" bolts, so that means that the instructions are all wrong too. Either that or the holes in the brackets are being drilled wrong at whatever place these things are made at. BTW, I had previously bought the UMI bolt-on relocation brackets, and recently decided that I should use the weld-on ones instead, and I just looked at the bolt-in ones, they have massive 5/8" diameter holes on the top also. I don't get it.

 

[Kirk's67SS]

Ramey is the guy to go to if you want any info/advise on what ever you need for your Car's Suspension

He provided me with the Right Parts for my Car based on how I was going to use it
and how the Adjustments should be Set on the DA Adj Front Coil Over Viking Shacks plus the DA Adj Rear Shocks for the Track

One of the most knowledgeable Suspension Guys that I have ever talked to

 

[BillyGman]

Ramey is the guy to go to if you want any info/advise on what ever you need for your Car's Suspension

He provided me with the Right Parts for my Car based on how I was going to use it
and how the Adjustments should be Set on the DA Adj Front Coil Over Viking Shacks plus the DA Adj Rear Shocks for the Track

One of the most knowledgeable Suspension Guys that I have ever talked to

And he works for UMI Performance?

 

[Kirk's67SS]

Yes Ramey Womer
here is his Email [email protected]
tell him I miss talking to him
last Emailed him in Jan 2020

 

[BillyGman]

Yes Ramey Womer
here is his Email [email protected]
tell him I miss talking to him
last Emailed him in Jan 2020

Very good. Will do. Thank you.

 

[aukai]

I modified a multi point box to fit, I didn't have a ready made product when I did mine. If it's bolt in "permanent", weld it in, and gusset it. I also lost the link to the top cross member, and used different reinforcement. Mine is ugly, but it works....

 

[Calculated Risk]

i have them on my rear, well at least a very modified version of them.

in my opinion that top bolt is over sized to allow movement so that the bracket can be moved to the proper position on YOUR car to put the bolt holes in the proper arc.

i mocked the brackets up with the rear under the car, at ride height and correct pinion angle, and then used a cheap aluminum yard stick with a hole drilled through it and bolted to the frame bolt hole on the inner/outside of the frame bracket, then i drilled an 1/8" reference hole in the yard stick at the length of my lower control arm. I set the bracket so that the holes were arranged so that the center of each hole was lined up with the ref hole, then I tack welded them in place. after that i removed the rear and completely welded the brackets.

 

[BillyGman]

I modified a multi point box to fit, I didn't have a ready made product when I did mine. If it's bolt in "permanent", weld it in, and gusset it. I also lost the link to the top cross member, and used different reinforcement. Mine is ugly, but it works....
View attachment 709645

i have them on my rear, well at least a very modified version of them.

in my opinion that top bolt is over sized to allow movement so that the bracket can be moved to the proper position on YOUR car to put the bolt holes in the proper arc.

i mocked the brackets up with the rear under the car, at ride height and correct pinion angle, and then used a cheap aluminum yard stick with a hole drilled through it and bolted to the frame bolt hole on the inner/outside of the frame bracket, then i drilled an 1/8" reference hole in the yard stick at the length of my lower control arm. I set the bracket so that the holes were arranged so that the center of each hole was lined up with the ref hole, then I tack welded them in place. after that i removed the rear and completely welded the brackets.

Mike and Rick, thanks for chiming in. And Rick, your explanation about the reason for the upper holes being oversized makes sense.

 

[UMI Tech]

Good evening.

That bolt is small on purpose. As you can imagine that stamped mount on the GM housing isn’t ultra accurate. Our brackets have to fit every housing ever made. You can use a 1/2” bolt. Heck I’ll even send you some if you want.

We absolutely make them in house. In PA - USA. They may have pulled a little. You can use some all thread and a few nuts to spread them a little. Should you need to? No. But we’re human and building a lot of them. They are supposed to be 2.400” +0.060” - 0.000 but they obviously got through.

Hit me at [email protected]

thx

 

[Tom Mobley]

Thx Ramey for stopping by.

 

[UMI Tech]

Yes Ramey Womer
here is his Email [email protected]
tell him I miss talking to him
last Emailed him in Jan 2020

Hi Greg. It’s always nice to talk with you. Your drag racing tuning notes and observations are some of the best I’ve seen.

 

[Stokerboats]

Billy, now you know why we say to speak to Ramey. Customer service.....

 

[BillyGman]

Good evening.

That bolt is small on purpose. As you can imagine that stamped mount on the GM housing isn’t ultra accurate. Our brackets have to fit every housing ever made. You can use a 1/2” bolt. Heck I’ll even send you some if you want.

We absolutely make them in house. In PA - USA. They may have pulled a little. You can use some all thread and a few nuts to spread them a little. Should you need to? No. But we’re human and building a lot of them. They are supposed to be 2.400” +0.060” - 0.000 but they obviously got through.

Hit me at [email protected]

thx

Thank you for chiming in. By "allthread" I take it you're talking about a threaded rod. I'll figure it out. Thanks for the offer to send me some 1/2" bolts. But that's ok, I just bought a couple. No big deal. I just wanted to know why there is .188" difference between the diameter of the supplied bolts and the bolt holes. Obviously Rick and you have explained it. That's appreciated.

 

[UMI Tech]

Thank you for chiming in. By "allthread" I take it you're talking about a threaded rod. I'll figure it out. Thanks for the offer to send me some 1/2" bolts. But that's ok, I just bought a couple. No big deal. I just wanted to know why there is .188" difference between the diameter of the supplied bolts and the bolt holes. Obviously Rick and you have explained it. That's appreciated.

No prob. Happy to help if at least a little. We've talked about moving that hole size a few times but inevitably we get a crooked housing bracket that requires some misalignment.

Any UMI questions I'm always available at [email protected].

thx

 

[BillyGman]

Yeah, I guess the fact remains that the bracket is made and intended to be welded onto the original axle tube bracket anyway. So the bolt is primarily used to hold the bracket in place while it's being welded. Of course once I weld it on, I'll leave the bolt in place for added protection/added safety. But I DO understand that it's supposed to be the welds that hold the relocation brackets in place.