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Old Dec 15, 2012 | 10:26 PM
  #21  
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If you want those little pain in the dick dings in your quarter panels then yeah listen to everyone who says don't get them. I need them now and regret not having bought them sooner.
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Old Dec 15, 2012 | 10:33 PM
  #22  
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Hey guys. Thanks for the kind words about UMI!

We have hundreds of customers thrilled with both our 2 and 3 pt SFC's. Weld-in sales vs bolt-in sales is about 50/50. Many bolt-in customers choose to stitch weld an insurance bead at a later time.

Our house car is pretty rigid on 3 point bolt-ins. Keep an eye on front mount tightness and they work fine.

Although some doubt their effectiveness, we have cars with no door gap trouble or wrinkle trouble after hundreds of passes and also see stock chassis vehicles without SFC's turn into a sheet metal pretzel after just a few passes.

We see no measurable performance difference between boxed vs tubular.

As mentioned, SFC's and junk shocks won't perform as well as awesome shocks and no SFC's but if I'm building a killer car I want both. It just makes too much sense to tie the rear pickup points to the front of the car.

From an engineering standpoint there's no industry standard measurement (as far as I know) which allows us to compare torsional rigidity easily between cars as well as between subframe connector manufacturers. To make a valid comparison and analyze the effectiveness we'd need everyone's numbers and also know what to do with said numbers. My point is, many of us think they help and many choose to use them. It's up to you to decide.

-- Ramey
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Old Dec 15, 2012 | 10:37 PM
  #23  
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Originally Posted by UMI Sales
Hey guys. Thanks for the kind words about UMI!

We have hundreds of customers thrilled with both our 2 and 3 pt SFC's. Weld-in sales vs bolt-in sales is about 50/50. Many bolt-in customers choose to stitch weld an insurance bead at a later time.

Our house car is pretty rigid on 3 point bolt-ins. Keep an eye on front mount tightness and they work fine.

Although some doubt their effectiveness, we have cars with no door gap trouble or wrinkle trouble after hundreds of passes and also see stock chassis vehicles without SFC's turn into a sheet metal pretzel after just a few passes.

We see no measurable performance difference between boxed vs tubular.

As mentioned, SFC's and junk shocks won't perform as well as awesome shocks and no SFC's but if I'm building a killer car I want both. It just makes too much sense to tie the rear pickup points to the front of the car.

From an engineering standpoint there's no industry standard measurement (as far as I know) which allows us to compare torsional rigidity easily between cars as well as between subframe connector manufacturers. To make a valid comparison and analyze the effectiveness we'd need everyone's numbers and also know what to do with said numbers. My point is, many of us think they help and many choose to use them. It's up to you to decide.

-- Ramey
Running any sales on boxed weld-ins?
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Old Dec 16, 2012 | 12:08 AM
  #24  
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Originally Posted by carbed86fox
i have some lake wood 50 50s in the rear and i just dont like the feeling of how much the drivers side picks up when it hooks i can just feel it twisting even from a roll
I said good shocks, lakewood shocks are cheap, non-gas charged drag shocks. Might as well have kept the stock ones in that case...
What you are feeling is the overly soft front suspension unloading (not enough rebound dampening) and the rear not moving due to too much compression dampening. The car is not actually flexing, the suspension is moving (being sloppy) making the car feel sloppy and loose.

Originally Posted by Grr
If you say they do nothing, you obviously havent seen creased 1/4 panels that result from flex, which never happens on a car with SFC's
This has been covered quite a bit by now.
1.) The rear quarter pannel dimples will still show up with SFC's, many have them appear after installing SFC's.
2.) SFC's brace up to the body mounting point of the rear LCA's, which is BEFORE the rear quarter pannels. So how do they help brace something they are not connected to?

Originally Posted by Amazin1
same here...i lowered my car with eibach springs and tokico's and then i did my subs and i noticed a difference...
Again, good shocks, the tokicos are mediocre at best.

Originally Posted by bayer-z28
^ I couldn't believe that it even effected braking performance! Un-fricking-believable difference. And before them when I would spin em from a roll, the car was rather unpredictable.. After SFC's, it would spin straight and was much more predictable and was more controllable. Get it loose and a degree or two off center, then just gently crack the wheel over to the other side and she would slide right over and straighten out. Such a difference in control.
Did you have aftermarket LCAs installed before the SFCs? Anything installed at the same time as the SFC's?
What you are describing is one of the many things I noticed after installing konis...

Originally Posted by LT1TransAm
If you want those little pain in the dick dings in your quarter panels then yeah listen to everyone who says don't get them. I need them now and regret not having bought them sooner.
As I just said above, unfortunately they wont help with that...
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Old Dec 16, 2012 | 12:13 AM
  #25  
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Midwest Chassis makes a great set of subframe connectors...
Weld them in...
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Old Dec 16, 2012 | 12:22 AM
  #26  
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Quote:
Originally Posted by Amazin1 View Post
same here...i lowered my car with eibach springs and tokico's and then i did my subs and i noticed a difference...
Again, good shocks, the tokicos are mediocre at best.

really?...cause i had bilsteins and replaced them with these. and if you think that sfc are useless then you have never drag raced a car with any sort of power. sfc are necessary to keep the body from flexing...period.
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Old Dec 16, 2012 | 09:43 AM
  #27  
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^ If you care about your car at ALL, you need SFC's. Again, best bang for the buck mod, right up there with gears, IMO... but my gears are sitting on my kitchen floor awaiting install in march when I order the axles.

Originally Posted by JD_AMG
Did you have aftermarket LCAs installed before the SFCs? Anything installed at the same time as the SFC's?
What you are describing is one of the many things I noticed after installing konis...
I installed LCA's about 3 years prior. First thing I did to the car.

When I installed the SFC's, I had just returned from deployment so I had a huge pile of parts to install. The SFC's were the last of the install, and was about 3 weeks after everything else was installed. Car felt completely different.

I talked my buddy into getting some for his Fox Stang and he had the same change. Stock Suspension on his though. Tightened everything right up and the car didn't feel disconnected anymore.

Ever hear of "torque dents" on the 4th gens?? yeah, that's caused by body flex. Those pesky dents on the pass rear above the wheel.
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Old Dec 16, 2012 | 10:09 AM
  #28  
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ya i think im gonna get some wled in ones i dont like the feeling of the drivers side icking up
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Old Dec 16, 2012 | 10:40 AM
  #29  
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Originally Posted by JD_AMG

2.) SFC's brace up to the body mounting point of the rear LCA's, which is BEFORE the rear quarter pannels. So how do they help brace something they are not connected to?
are you drunk? do the 1/4 panels just float in mid ******* air or what? hey smartass guess what, the quarter panel and associated framing is what provides the torsional ridgidity for the entire back half of the car!
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Old Dec 16, 2012 | 11:20 AM
  #30  
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Originally Posted by Amazin1
really?...cause i had bilsteins and replaced them with these.
Really...
and if you think that sfc are useless then you have never drag raced a car with any sort of power. sfc are necessary to keep the body from flexing...period.
If you want to prevent the body from flexing you buy a cage..period..

Originally Posted by bayer-z28
^ If you care about your car at ALL, you need SFC's. Again, best bang for the buck mod, right up there with gears, IMO... but my gears are sitting on my kitchen floor awaiting install in march when I order the axles.
I installed LCA's about 3 years prior. First thing I did to the car.
Polyurethane?
Im asking because Ive read that when the poly bushings bind they can actually twist the body side mounting point, and naturally SFC's that cover this point will add stiffness so those mounts don't twist, and you will feel that difference.
I talked my buddy into getting some for his Fox Stang and he had the same change. Stock Suspension on his though. Tightened everything right up and the car didn't feel disconnected anymore.
Foxs are terribly weak chassis, those actually DO need SFCs.
Ever hear of "torque dents" on the 4th gens?? yeah, that's caused by body flex. Those pesky dents on the pass rear above the wheel.
Originally Posted by Grr
are you drunk? do the 1/4 panels just float in mid ******* air or what? hey smartass guess what, the quarter panel and associated framing is what provides the torsional ridgidity for the entire back half of the car!
Ugh... making me look up old threads...
https://ls1tech.com/forums/suspensio...bout-sfcs.html
I want to highlight these posts from that thread, but make sure to read it all:
https://ls1tech.com/forums/6712303-post13.html
https://ls1tech.com/forums/6717242-post26.html
More:
https://ls1tech.com/forums/suspensio...ws-best-3.html
https://ls1tech.com/forums/6312129-post24.html
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Old Dec 16, 2012 | 01:04 PM
  #31  
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What do you tie the cage into on a race car? Sub frames FTW. Yes they are welded to the unibody and pass through the floor. Look at any Stock or SS car and look at how they do the rear. A bolt on or welded bar under the car is still the same basic principle.

If you auto X or street drive then SFC are probally just added weight.

Drag race or road race then they are a good idea. My 99 vintage sq. tube ones reinforce the rear front lower control arm mounting point. They also allow the roll bar front down comers a place to mount. The bars plate and the SFC plate sandwitch the frt sub . So it all comes down to what makes you feel comfortable about YOUR car not some one elses!!! When I jack up my frt of the car that whole side rises about the same height. Frt to back. Thats rigid in my book.
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Old Dec 16, 2012 | 01:49 PM
  #32  
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Originally Posted by JD_AMG
Polyurethane?
Im asking because Ive read that when the poly bushings bind they can actually twist the body side mounting point, and naturally SFC's that cover this point will add stiffness so those mounts don't twist, and you will feel that difference.

Foxs are terribly weak chassis, those actually DO need SFCs.


Ugh... making me look up old threads...
https://ls1tech.com/forums/suspensio...bout-sfcs.html
I want to highlight these posts from that thread, but make sure to read it all:
https://ls1tech.com/forums/6712303-post13.html
https://ls1tech.com/forums/6717242-post26.html
More:
https://ls1tech.com/forums/suspensio...ws-best-3.html
https://ls1tech.com/forums/6312129-post24.html
Yeah, polly. They're boxed Hotchkis LCA's which I will soon replace with double roto UMI pieces. I don't think preventing the mount from twisting will make that big of a difference when I can feel a difference with the way the car handles subtle differences in the road with just driving. IMO, My SFC's were well worth it and I'd recommend them to anybody.


And there may be multiple "stages," if you will, to stiffening a car. SFC's would be the initial stage. Not everybody will find a cage feasible or justified. The only thing connecting the front to the backs of these cars is some stamped sheet metal which is prone to flexing, I don't care how many hems you incorporate.

Last edited by bayer-z28; Dec 16, 2012 at 01:56 PM.
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Old Dec 16, 2012 | 02:16 PM
  #33  
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If anyone autocrosses it would be nice if they were to chime in here. Most of the discussion has pertained to drag racing. Every test drive/review of a car I have ever read mentions the cars structural rigidity in how the car handles - they don't like body flex when you are taking a hard turn. Above someone mentioned subframe connectors being dead weight with an autocross car. I'd have to disagree. I believe improved structural rigidity would be a good thing in either case.
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Old Dec 16, 2012 | 03:17 PM
  #34  
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I'm on Strano springs and Bilstein shocks; they made 100x the difference the subs did. I added the subs afterward; there was NO difference. Body still had squeaks and creeks, still lots of movement in the body (can really tell between the windshield and T-top), the little creases still appear in the rear fenders and the body still twist when entering an uneven drive. The people saying they can feel the difference are the same people who say they can feel a 10hp difference; other words, they're try to justify the money they spent.

Helping sagging doors? Ha, that seems to be cause by the doors themselves coming apart; subs are going to help that?

Truth is I'd be pissed I spent the money on subs if I wouldn't have gotten them on clearance cheap. If you want to blow money on a set, so be it. When it doesn't wow you or you still get the creases in the body panels, don't say you weren't warned.

ETA: Strano has already posted his opinion on subframe connectors and I think he's as qualified as any to say they do nothing for auto-x and road racing. Well, actually they do give you some convenient jacking points under the body just as a STB makes a nice tow point.

Last edited by Kurt D; Dec 16, 2012 at 03:22 PM.
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Old Dec 16, 2012 | 03:55 PM
  #35  
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i don't have to justify crap to you or anyone else. how i spend my money is my business. and in my opinion the subs helped out my car immensely.
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Old Dec 16, 2012 | 04:54 PM
  #36  
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^ Exactly.. I can't believe how this thread turned into a pissing match over something like this.

Originally Posted by Kurt D

ETA: Strano has already posted his opinion on subframe connectors and I think he's as qualified as any to say they do nothing for auto-x and road racing. Well, actually they do give you some convenient jacking points under the body just as a STB makes a nice tow point.
Really??

Originally Posted by Sam Strano
The key here is simple. Those that have done good shocks notice less difference with SFC's than those that have stock shocks. And there is a simple reason why: The shocks are the first line of "defense" against loose, sloppy feel and impact harshness. If the dampers suck then anything that can help you like stiffening the structure a bit will. If the shocks are good, and do their job well, the SFC's aren't as noticeable.

Are SFC's bad? Hell no, I sell them, and I have no issue with them. But the only instance where I can say they should be done before suspension parts is if the car is beat to hell and maybe drag raced hard, a lot.

I sell all those parts, and a lot more. I know how the parts work, and work with each other. Really, what you are seeing here are the reasons I prefer to speak with people about their particular needs and wants instead of relying on internet wisdom, fwiw.

Originally Posted by Sam Strano
I'd be that member, and it makes perfect sense. Of course, you can choose not to beleive me when it comes to suspensions on the 4th gen, that's you choice.

SFC connectors do not come within FEET of the quarter panels, and if you've even seen a car wheelhop of brake up without of without SFC's you'll see the same action happening. The quarter panels actually flex and buckle, it's true and I know that. To compare my car having them to a car that has SFC's not having them is a poor decision. My car, or any car driven and setup like mine, goes through things that no street car, no matter how hard it's driven does. For instance I've seen brake hop violent enought to break a stock welded muffler off the intermediate pipe.

I'll reiterate to you the fact that I know of one 4th gen with over 310k miles on it, sans SFC's. Sure it has a few squeaks and rattles, but is much better than most cars with 1/3rd the miles. BTW, that car is a stiffer sprung car (1LE, and is autoxed, daily driven and drag raced almost all the time). Further, I'll add that one customer/member removed his SFC's in order to race in a lower class (ESP vs. SM) and was very suprised by the lack of difference he felt.

I know you felt the difference with SFC's. But it's a simple reason, the stock shocks transmit loads into the body that do not get there with good shocks like Koni's or Bilstein's. It's those things that make the body quiver when driving down the road. So you can put SFC's on to help, and still have lousy shocks. Or you could put good shocks on and realize you don't need the SFC's for squeaks and rattles and such since much less shock is getting to the body in the first place.
I have more to post if you would like....

Last edited by bayer-z28; Dec 16, 2012 at 05:02 PM.
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Old Dec 16, 2012 | 06:14 PM
  #37  
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I've been mulling this over for a long time. I really don't have a clear idea of whether SFCs would benefit me or not. My car is mostly stock, and makes "only" 250 rwhp. I rarely drag race it, it's mainly a cruiser, but I do like to corner as hard as the car can handle. I run good tires and have Koni SAs, other than that the suspension is stock.

Cue Bayer chewing me out for not getting them yet
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Old Dec 16, 2012 | 06:20 PM
  #38  
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^ You live in Dragon-land anyway...


But they're cheap enough.. Why not?? I gotta let you drive the Camaro some time.

Last edited by bayer-z28; Dec 16, 2012 at 08:33 PM.
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Old Dec 16, 2012 | 07:56 PM
  #39  
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they are pretty cheap but when you buy parts that sometimes just a waste of wieght and space it adds up so i just wanted to make sure before i spent my money thanks guys
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Old Dec 16, 2012 | 08:04 PM
  #40  
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**** the SFC and get good shocks then
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