plndtx

I went to have my Spohn vert subframe connectors installed today but we ran into a problem. The rear portion connected just fine to the lower control arm. But the SFC started making contact with the brace (ASC addition?) only a few inches toward the front of the car. This made the front of the SFC about 2-3 inches away from the brace and about 2 inches below the floor pan.
Question 1.
The instructions mention using a jack to get the SFC to butt up against the floor pan but how do you get the SFC to lie up against the brace for the length of the SFC?
Question 2. The guy at the shop lifted the car by the body even though the instructions say not to do this. The instructions say to support the car by the A arms and by the 'rear housing'. Would this cause the problems described.
Question 3. Will the rivets get in the way if we figure out a way to get the SFC to line up?
Question 4. The tech was troubled by the undercoating. He mentioned that he wasn't sure how he was going to get it off. Could the undercoating be causing the alignment problem and is it that big a deal to get it off. I thought an air grinder would take it off pretty quickly.

The shop called Spohn twice and was told to look at the pictures on the web site and the second phone call they said that they had never had a problem like what we were describing. (I'm kinda disappointed they didn't seem to want to help.)

Here are some pictures I took of the problem.
Thanks

plndtx

Bla Bla

plndtx

SFC removed so you can see the rivets.

plndtx

The tech added the transmission jack? after told him the instructions said the syspension must be loaded.
He said this made the problem worse.

plndtx

The last pic. I promise.

WillSpeedy

Sorry to here your trouble.
I did a bit of research before I got my SFC's. The only ones to fit a convertible without a lot of trouble are the Alston's from TDS( top down solutions) So that's what I got and they work fine.
Also sounds like the shop you are dealing with are a bunch of morons if they can't scrape off some undercoating?
You need to load the suspension because the way our cars flex so much that if you put them on unloaded when you load the car the alignment might be off. And you will throw a bunch of stuff out of whack.
Just my opinion.

Mr. IROC-Z

iTrader: (1)

I got my SFC's from Mac. No problem to install also.
I'm sorry for the problem. I actually did not install them myself.

I had the shop weld them into place, and they went in perfectly.

Tommy

Jaysz28

iTrader: (30)

I've had Spohn SFC's installed on a 91 Z28 and 92 Z28 vert. The wieght of the car has to be on the suspension. As previously stated, the flex can through a lot of things out of alignment. Try to find a shop with a drive on lift! Only way I trust it to be done.

Now the 92 z28 had no issues with the install. Of course in 92, the basically glued the cars together, so the unibody was still pretty straight.

The 91 on the other hand looked like your car. I had to use a pry bar to hold the front of the SFC against the factory SFC. Yes, you will have to grind some of the undercoating off so it can be welded. Hell, 5 mins of prep work with a drill and wire brush. Not that diffiuclt.

Now I spoke with Steve about the fitment problems I had on the 91. He explained that the verts are hand built (true) and that the factory SFC's are all exactly straight or in the exact spots. They sorta ended up where ever the guy glued and riveted them in.

I pushed mine up against the rivets, then welded the fronts in place, and worked my way back tacking the Spohn SFC to the factory one. Then my welder used small bits of metal to well them to the floor. The difference was amazing!

Good luck

-jason

plndtx

Jaysz28,

Could you look at this link to pics I posted on the chassis forum. Did the rivets on your car hang down as far as mine. Steve offered to make a SFC to fit my car if I would give him the distance from my lca to the ASC brace. Now I'm afraid the rivets will prevent the proposed SFC from getting close enough to the floor pan to be welded.

https://www.thirdgen.org/techbb2/sho...hreadid=349426

Jaysz28

iTrader: (30)

Well the rivets are on all 3 of the verts I've worked on. What the tech had to do was use small pieces of metal to bridge the gap.

The alternative I guess could be using a piece of flatstock welded to the SFC then welded to the floor.

Like I said, these cars were hand built and not very well. If you want something easier to install, I hear the Alstons do a pretty good job. I plan on adding them to my vert later on

-jason

plndtx

I think I might have to go with the alstons.

The only other thing that might help is to reverse the rivets. Example, remove one rivet at a time by drilling it out. Then put a new rivet back in but instead of installing from the top, install from the bottom. The head of the rivet on the top side only apears to be about 1/8 inch thick. This might get the SFC closer to the floor pan.

I think it is too much work.

Could someone post a link of where the Mac SFC's are. I would like to take a look. Anybody else make vert SFC's, please post a link. BMR make vert SFC's
Thanks for everyones suggestions/comments.
Chris

drop-top IROC

MAKE SURE THE SUSPENSION IS LOADED WHEN YOU ARE WELDING THE SFC'S ON!!

In the pictures you show, there is no weight on your suspension using the type of rack that is shown- you need a 'drive-on' rack. This is critical!

I got a set of the Alston SFC's from TDS (see banner at top of page) and they fit perfectly. They are, however, not quite as stiff as a 'perimeter-type' SFC, but they are light years ahead of the boxed rail that ASC installed on these cars.

Cadillac

Is this the case for all SFC installs? I'm think about getting some from Lon this Spring/Summer and having them welded in.

Those are the ones I am considering. What other choice is there (link please)? Where do I look at the perimeter types?

plndtx

Cadillac, are you thinking of buying perimeter style SFC's?
Better check your car for the ASC installed rivets. You could be looking at an installation nightmare. (That is if you are installing them on a vert.)

I posted some more pics in a post on the chassis forum if you want to take a look.

Cadillac

I was only sonsidering the SFC's that Lon sold because I know for a fact they will fit. I didn't know there were any options to consider.

This the thread in the Chassis forom. Looks like you are getting some new ones from Spohn?

drop-top IROC

Has anyone else had this problem with the Spohn Convertible SFC's? I was thinking about getting a set myself in the future to augment the Alston/TDS ones that I already have.

Before I bought the Alston/TDS ones, I had ordered a pair from Kenny Brown Performance. When I received them, it was obvious that they weren't going to line up correctly because of the added rail on the convertible. The techs at KB, and a few other folks on this forum, told me that they will fit on a convertible with some minor cutting. To me, if I have to hack up a part to make it fit, it wasn't specifically designed for the car. Too bad- the Kenny Brown SFC's are some of the beefiest looking, well made SFC's I've come across. Do they even still make them for 3rd Gens? Their website is currently under construction....

plndtx

Cadillac,

Steve Spohn offered to make a set of SFC's to fit my car if I would measure the distance from the LCA to the ASC 'brace'. Remember, I had two main problems with my installation. The first one was that SFC was fitting too tightly against the ASC brace (right after the rearward bend in the SFC). This caused the front of the SFC to be about 3 inches from the ASC brace.

After I got the measurement that Steve needed, I just held the SFC up where it needed to go (the flat portion that connects to the lca was pointed down). I wanted to see if the rivets were also going to cause problems. And indeed, with the rivets hanging down about 3/8 inch, the distance between the SFC and the floor pan was enormous. Somebody mentioned welding pieces of flat metal between the floor and the SFC. I think that would not look that good and be a major pain.

If I need to clarify some of this let me know. Its hard to describe some of this.

I may consider making the mods (replaceing rivets with welds, using pieces of metal to bridge gap) and going with Spohn, if I ever install a really high output engine.

Right now I'm kinda tired of screwing with this and I think I am going to bolt in a pair of alstons. I would have them welded in but I just put my interior back together and I don't know of another shop to do the welding. I'm not going back to the one I used before.

Does anybody have pictures of their welded in alstons. I am curious what it looks like welded to the tranny crossmember/subframe and the LCA's? Did you take the interior out when you welded the alstons?

Thanks everyone.

Chris

Cadillac

Thaks for the clarification. For my needs it sounds like the SFC's from TDS will do fine for me.

Educational thread.

drop-top IROC

Unlike some other SFC styles, you do NOT have to remove any of the interior (carpet or otherwise) to install the Alstons. They attach to the actual subframe, not the floor pan. I'd recommend having them welded in rather than bolted. Over time, the bolt holes will elongate and your SFC's will be less effective.

I'll see if I can't dig up some pictures of my install, but I'm sure someone else on the board has some (I've seen them posted).

Matthew91-Z28

I have the MAC sfc's and installation was easy. Its performance i'm worried about. My car was stiffer after installing them but I still get lots of flex when going up a steeper driveway diagonally.

Is this still common with spohn sfc's?

Otherwise, they work fine. Some clearance issues with tall speed bumps, but nothing to really complain about.

There is something missing but I dont know what yet. I feel like I need to add a x-brace or something between them to get the greatest rigidity. Still thinking about it

Cadillac

OK... Like I mentioned, I've learned a lot from this thread. I've all but settled on getting the SFC's from TDS but now I am reconsidering simply because the Spohn installation seems to be a tad easier (will cost me less).

Is the point if this thread that the Spohn SFC's for convertibles may not be a direct fit? If not, then I am ordering Lon's stuff which is what I planned on doing anyway.

My goal is simple -- Make it rigid and remove the wet noodle feel.

plndtx

Cadillac,

What does the area located 2 inches inboard from your ASC brace look like?
Any Rivets? How far do they hang down?
If you happen to have about a 1 1/2 inch diameter pipe, hold a piece up by the ASC brace and the floor pan. What kind of gap are you looking at between the pipe and the floor pan.
I was looking at about a 1/2 inch gap that was going to have to filled up somehow. I decided to return mine for a refund. (BTW, they have had my returned SFC's for 2 1/2 weeks and I still have not received my refund). I feel a flame post brewing.
Could anybody with a successful install post some pictures.
I can't believe that this has not come up before. Maybe I have an oddball car??
I posted a link to this post in the chassis forum and got some feedback on that post if anybody is doing research on the subject.

plndtx

I just wanted to add a final note to this post in case someone hits it in a future search.

I called Spohn the day after my previous post and asked why I haven't received a credit on my credit card. I was told the 'check was in the mail'. They said it was easier for them to cut a check rather than deal with the credit card companies on issuing a credit.

Well, that same afternoon I made this phone call, the check arrived in the mail. I am satisfied.
Too anyone who may be considering Spohn SFC's for a vert, it doesn't appear that others are having this problem. I am confused about the who situation. But Spohn did try to resolve this issue by offering to make a custom SFC for me. They also offered me a refund when I told them I didn't want to tackle the rivet issue.

Cadillac

Uh oh... looks like i have the rivets there too (attached pic).

I think I'll be going with the SFC's from TDS unless someone can tell me about the ones from MAC.

dirtfarmer

Well I have to put in my

I got my SFC from Lon and they fit like a glove. Some of the welds were a little tough. I installed them my self. It was worth it, the car feels tight. If some one does not post a photo I'll shoot some and post them.
They made my 91 RS ready for the next mod...New tubular sways, nylon mounts and wonder bar. All of which I got from TDS.
Later

Ron

Cadillac

Dig it. (Click me)

83 Crossfire TA

iTrader: (2)

Huh, from looking at the pics I’m not seeing a problem… well I’m seeing a lazy installer that doesn’t want to clean the undercoating off to make room for them and that doesn’t seem to know how to install a set of subframe connectors… It only takes being a fraction of an inch out (the thickness of the undercoat) in the back to cause the misalignment in the front, and if they’re intended to be stitch welded along the sides there is no way that you’ll do that without that tight a fit and without removing the undercoat… You almost always get stuck using a jack or something similar to get things positioned correctly after you have the whole thing properly loaded, and if it wasn’t that tight you’d rip your stitch welds out right away as soon as you drove it.

Not being the biggest spohn fan, I don’t see anything they did wrong here…

gchu

My installer went through the same problem with the fitment with the rivets and/or gap between the floor and the SFC. He started thinking about grinding off the rivet heads, but I managed to get him to fill the gap with bits of metal instead.

Overall, he did a great job removing the undercoating and then repainting/coating everything so the bottom looks brand new! Unfortunately I have a slight oil leak so it didn't stay that way for long.

It was a pricey install (about $300 - not counting the SFC's)........

plndtx

Get us some pics when you can.

dual_88s

Have 2 88 convertibles. Bought Alston SFC from Lon at TopDown and had them welded in. (BOTH cars) The shop I went to normally works on 'off road' vehicles. (Red River Off Road)

The owner of the shop did it one night after hours for $50 since he had never done any SFC's on Third gens. Didn't want to tie up his bay during the day and deny one of his mechanics a few dollars.....

He lifted the car off the floor, then set it back down on 4 floor jacks that he verified were equi-distance from the floor (height) on the 'A' frames and both sides of the pumpkin on the rear axle. He had it about 18" off the floor. He cleaned off the old undercoat, tack welded them in place. drilled the holes for the bolts, bolted them in and then raised the car up to make it easier to work on and finished welding it in place. Did not lift or remove the carpet, he took it easy and slow on the welding to be sure he would not 'burn' it up.

After he was done, he sprayed some undercoat on the brackets and the welds and bolts.

ALL the freakin' difference in the world......and they do not hang any lower than the exhaust systems.

Cra-Z-Canuck

I have to agree - I just had the Spohn's and the Alstons installed at a shop across the street, so I spent a lot of time watching - yes he did have to grind down some of the rivet heads. But he had it on a drive-on lift and then put a small jack on the lift under the connector to shove it up into place and it fit like a glove. So did the Alstons (which he did first). I also put in the Edelbrock strut tower brace at the same time -RADICAL difference in the car now. Drives so much nicer, bumps are soo much smoother and 85% of the squeaks and rattles are gone....HIGHLY recommended.