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SFC comparison thread

Old 05-26-2012, 05:10 PM
  #151  
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Re: SFC comparison thread

I'm looking at getting a set of Alstons for my car. Though there seem to be conflicting info on how to install them. I've read that some people just weld them on with the full weight of the car. Others seem to be welding them sans engine and the like with a non weighted suspension. We have a flux core welder (though we could also set up a true mig setup) and I was thinking of doing the work myself to install them. Along with some seam welding. How exactly does one install the inner ones? I will also install the outers but those will come later. I take it I can order them through TDS?

EDIT*************
I just found the horror thread from 2004 with the group purchase batch. Where the passenger front cup didn't fit. People had to do all kinds of crazy things to get them to fit. Including sending them back to Alston. Has this problem been resolved?

Last edited by L695speed; 05-26-2012 at 09:19 PM.
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Old 05-27-2012, 02:31 AM
  #152  
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Re: SFC comparison thread

Have to say that the inners (MAC) did a fantastic job of stiffening the chassis. There are debates about which one is better and so forth but being curious myself I tested this theory and installed outer (SPOHN) SFC's as well, after the inners. The difference was more noticeable after the inners but that could simply be because the outers were installed after the front and rear subframes were already tied together so it wouldn't make much difference. It did make a small difference and noticeable especially when I put the car on the lift as I can open doors without it scraping on ground effects from body flex, I can jack the car up via the SPOHN SFC's which is a nice bonus, and while pulling out of driveways chassis flex was greatly reduced (although is still somewhat present but that's because of t-tops, which I have a great idea on how to improve later on for another project.)

And yes I welded the outers all along the rocker as well.
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Old 07-12-2012, 03:21 AM
  #153  
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Re: SFC comparison thread

I’m also curious how easy it is to install an Alston because I’m planning to do it myself (bolt in first myself, and weld in later at a shop). Does anyone have any difficulty installing them? If so, what kind? As L695speed quoted, cup fit problems can happen often?
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Old 08-02-2012, 12:01 PM
  #154  
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Re: SFC comparison thread

When I performed the build on my Beasty in 1999, I used Southside Machine subframe connectors. They are outside, weld in connectors. They were very well made of .095 wall 3"X2" tube and cut/welded to fit. I had to make minor adjustments and I also made buttrices for the front joints to improve the connection at those points. I did the installation with the vehicle complete and supported by the rear axle and the front wheels on a flat surface so that the chassis would be in its truest position. I'm glad I did all of that because these connectors made the chassis so rigid that it would have retained any out of true that it had when the install was done. I was careful of course to grind and clean all the ares where you will be welding to get good penetration. Afterward, I liberally sprayed the welds with chassis black epoxy.
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Old 08-22-2012, 09:44 AM
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Re: SFC comparison thread

so im curious as too which outer connecters would work best for me seeing as i do not care about weight or price because the car has t-tops im very worried about turning it into a pretzel whith wheels, i dont plan on selling this car and the connectors are going too protect it from my future plans and related abuse so i see them as a very important part of the car too invest in ,

the reason i don't want too do both is ive heard that the inners make it next too impossible too run exhaust with decent clearance and seeing as im country kid i need to be able to go down a gravel road,or over large speed bumps and not worry

about how much torque can a t top car handle whith outer sfc ive heard there was a brand that actualy rated their connectors to 500 horse in a t-top car

Last edited by g00d$p33d; 08-22-2012 at 09:48 AM.
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Old 08-22-2012, 10:39 AM
  #156  
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Re: SFC comparison thread

I have a T-Top car with about 270hp and 350tq and I have MAC inner connectors and SPOHN outer connectors. They are both tubular black powdercoated metal. I prefer tubular to square. UMI makes a good square frame connector as well. There are other companies out there but those two I would say are the main ones these days.
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Old 08-27-2012, 10:58 PM
  #157  
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Re: SFC comparison thread

I’ve got an Alston subframe connector, and asked my shop to weld it in, but they said the rear subframe section where the connector attaches is too thin steel and eventually it will twist or break. They don’t even recommend using the connector. What do you think?
They also said any common welding will cause severe rust in the long run, and if I want to keep my car fit for a long time, I should avoid welding as much as possible. What do you think? I would like to hear your opinions on this too.
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Old 08-27-2012, 11:12 PM
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Re: SFC comparison thread

Originally Posted by JunJun View Post
Iíve got an Alston subframe connector, and asked my shop to weld it in, but they said the rear subframe section where the connector attaches is too thin steel and eventually it will twist or break. They donít even recommend using the connector. What do you think?
They also said any common welding will cause severe rust in the long run, and if I want to keep my car fit for a long time, I should avoid welding as much as possible. What do you think? I would like to hear your opinions on this too.
My opinion? Find a new shop that has a clue of what they are doing, since it is obvious that the shop you went to doesn't.

After welding you paint/undercoat5 to prevent rust from appearing!

And no, it will not " eventually it will twist or break".....While it is thin it just means that a competent welder needs to do it which obviously is not that shop! If it is really that thin to break, then why are the LCAs, that transmit all the driving force into the chassis, located right there? If they were even remotely right then the LCAs would rip loose right there too.
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Old 08-28-2012, 01:10 AM
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Re: SFC comparison thread

About rusting, I also had the same opinion as you, and couldn’t believe at first what they were saying. But what they mean is, even with those undercoating and painting, rust appears, because welding afterwards, unlike when built as a new car, cannot exclude impurity completely, and this will cause rust sooner or later. Actually my camaro has a welded steering gearbox mount (welded 3 years ago) and it has some rust already even with undercoat and paint. The shop has several customers who use 60’s or 70’s camaro as race cars and has a lot of know-how about old cars, so probably they are talking in a very strict sense.
About the rear subframe where the connector attaches, they prefer to use LCAs, instead of the section the Alston connector uses, to attach the connector, because LCAs are more solid. I also compare those two, and obviously LCAs use thicker steel, while the other uses very thin one.
Anyway, they seem to be talking from a very strict and professional point of view (they even said just adding subframe connectors upsets rigidity balance, so reinforcing worn-out factory spot welds is the best), so maybe I can ignore to some extent. I would appreciate if those of you who use Alstons for several years could give me some feedback.
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Old 08-28-2012, 11:05 AM
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Re: SFC comparison thread

Hi JunJun,

I've had subframe connectors for about 6 years now. I've had the MAC inner style (the same as the Alstons) from 2007 to about late 2009. At this time I decided to get the outer style frame connectors as well because I have t-tops and the more rigid the frame the better, especially since F-bodies are unibody cars that are VERY flexy and need all the re-inforcement they can get. In late 2010 I decided it was time to completely paint the chassis and everything I could see / get to underneath my car (minus powdercoated SFC's and other things like exhaust etc.) I used POR15 which worked amazingly and has held up ever since. It still looks as if I just painted it. There is NO rust underneath my car and after many things have been welded on my car (SFC's, LCARB's, PHBRB's, etc.) no rust has appeared anywhere.

That being said, I don't drive in the winter and have rarely driven in the rain. I wouldn't recommend even driving a camaro in the winter anyway but that's just me.

SFC's are only a good thing in these cars trust me. Besides adding weight and maybe sacrificing minor ground clearance, they reinforce the car. Period. If they are installed properly the car's rigidity balance shouldn't be affected. I think what you mean by that is that if they weld it when the car is on a lift it will be welded while the body is flexing which is NOT good. The car need to be seated and in its natural position (weight on the tires, not on the frame) and then the shop can weld them in.

Since you have convertible I would double check that they fit with convertible I'm not sure which ones fit or don't you'll have to check.

I'm not sure if that shop is the best either if that's what they are telling you.. Anybody who knows these cars knows that they NEED subframe connectors badly..

Good luck!
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Old 08-28-2012, 02:23 PM
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Re: SFC comparison thread

When you go to prep for installation, completely strip everything bare, then use weld-thru primer, helps with protecting areas you dont end up welding and sometimes may miss when painting after.
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Old 08-31-2012, 02:21 AM
  #162  
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Re: SFC comparison thread

Hi, hellz_wings, thank you for your reply.

Your explanation is quite encouraging, and I'm very inclined to using the Alston I've got.
Actually I'm still afraid rust might appear in the long run, and some other crack might be caused by the rigidity of the Alston, but I also know it's very stressful to drive a car with a very flexy body.

Probably a regular inspection will prevent any damage the Alston might cause (if it does), and it will be more worthy to be able to enjoy a more rigid frame, than just being afraid of the future corrosion my car might or might not have.

BTW, the shop also said how and where I drive my camaro also decides how much it rusts, and in that sense your environment seems best. Like you, I also don't drive in the rain, and my house is not near the sea, and we don't have much snow in winter, so probably I don't have to worry about rusting that much (although Tokyo has a more humid climate).

Thank you again for giving me helpful feedback.
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Old 08-31-2012, 03:27 AM
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Re: SFC comparison thread

Originally Posted by JunJun View Post
Hi, hellz_wings, thank you for your reply.

Your explanation is quite encouraging, and I'm very inclined to using the Alston I've got.
Actually I'm still afraid rust might appear in the long run, and some other crack might be caused by the rigidity of the Alston, but I also know it's very stressful to drive a car with a very flexy body.

Probably a regular inspection will prevent any damage the Alston might cause (if it does), and it will be more worthy to be able to enjoy a more rigid frame, than just being afraid of the future corrosion my car might or might not have.

BTW, the shop also said how and where I drive my camaro also decides how much it rusts, and in that sense your environment seems best. Like you, I also don't drive in the rain, and my house is not near the sea, and we don't have much snow in winter, so probably I don't have to worry about rusting that much (although Tokyo has a more humid climate).

Thank you again for giving me helpful feedback.


Get the weld-thru primer to coat the area before welding them in, and paint with something quality, like por-15 and you will NOT need to worry.
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Old 08-31-2012, 03:42 AM
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Re: SFC comparison thread

POR15 will not stick to clean bare metal, only rusty, etched or blasted surfaces. Choose something better.
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Old 08-31-2012, 10:18 AM
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Re: SFC comparison thread

Originally Posted by Twin_Turbo View Post
POR15 will not stick to clean bare metal, only rusty, etched or blasted surfaces. Choose something better.
That's why you use their product that costs like 30$ for the whole underbody and more.. It's called "Metal Ready" and it's a metal etcher. It works well and the POR15 sticks great. Ofcourse, you have to degrease it and clean it really good before.. I sprayed the heck out of the whole underbody TWICE with their degreasing product called "Marine Clean". It works wonders. It's awesome! So, you use Marine Clean, then Metal Ready and then you can spray or brush on POR15. They recommend 2 coats but I only did one as I never drive it in the rain or snow and so for me it's fine. 2 years later it still looks as if I just did it yesterday.. I had a thread on this let me try to find it..

Here: https://www.thirdgen.org/forums/body...ml#post4668217

You can see my results as well as another guy who posted pics of his POR15 work on his car.

Last edited by hellz_wings; 08-31-2012 at 10:21 AM.
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Old 08-31-2012, 01:43 PM
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Re: SFC comparison thread

Been following this thread for a while. I have the macs, and if your worried about corrosion dont. Paint the welds and undercoat them and surrounding area. Ive had mine since 1996. So that is a testememt for their longevity if you periodically check and maintain them. If you have and rust bubbles or spots needing to be touched up just use red scotchbrite and recoat. Mine are black when i had a few spots I just scotchbrited them and used vht chassis and rollbar paint epoxy. They look brand new. I periodically clean and check welds and recoat if needed. Mine have been in almost 17 years. Macs are well made and actually look like they belong their. Im partial to this design vs the ones that weld to the side of frame rails. Tubular is stronger imho, they really stiffened up everything. I at the time was pulling 1.70 short times with these and drag radials way back when. I prob wont add anymore chassic stiffening unitil if and when I ever put a cage in it. Ill post up pics when I can. Take care.

Last edited by IROCZ1989; 08-31-2012 at 01:47 PM.
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Old 09-01-2012, 01:10 PM
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Re: SFC comparison thread

Originally Posted by hellz_wings View Post
That's why you use their product that costs like 30$ for the whole underbody and more.. It's called "Metal Ready" and it's a metal etcher. It works well and the POR15 sticks great. Ofcourse, you have to degrease it and clean it really good before.. I sprayed the heck out of the whole underbody TWICE with their degreasing product called "Marine Clean". It works wonders. It's awesome! So, you use Marine Clean, then Metal Ready and then you can spray or brush on POR15. They recommend 2 coats but I only did one as I never drive it in the rain or snow and so for me it's fine. 2 years later it still looks as if I just did it yesterday.. I had a thread on this let me try to find it..

Here: https://www.thirdgen.org/forums/body...ml#post4668217

You can see my results as well as another guy who posted pics of his POR15 work on his car.

I've been using POR for over 15 years and know very well how and when to use it. I was just pointing out that smearing it over bare metal will not do any good. Didn't I mention etching?????
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Old 11-30-2012, 09:18 AM
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Re: SFC comparison thread

Originally Posted by IROCZ1989 View Post
Been following this thread for a while. I have the macs, and if your worried about corrosion dont. Paint the welds and undercoat them and surrounding area. Ive had mine since 1996. So that is a testememt for their longevity if you periodically check and maintain them. If you have and rust bubbles or spots needing to be touched up just use red scotchbrite and recoat. Mine are black when i had a few spots I just scotchbrited them and used vht chassis and rollbar paint epoxy. They look brand new. I periodically clean and check welds and recoat if needed. Mine have been in almost 17 years. Macs are well made and actually look like they belong their. Im partial to this design vs the ones that weld to the side of frame rails. Tubular is stronger imho, they really stiffened up everything. I at the time was pulling 1.70 short times with these and drag radials way back when. I prob wont add anymore chassic stiffening unitil if and when I ever put a cage in it. Ill post up pics when I can. Take care.


So to be clear on this you are running the MAC subframe connectors only, not the Mac and another outboard type as well ?

If so and you are running drag radials and pulling 1.70 60 foot times thats good enough for me.

You say the Mac is exactly the same as ALSTONS ?

Is the MAC version still sold ?

Thanks...............
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Old 11-30-2012, 09:30 AM
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Re: SFC comparison thread

Originally Posted by IROCZ1989 View Post
.....Im partial to this design vs the ones that weld to the side of frame rails. Tubular is stronger imho, they really stiffened up everything. I at the time was pulling 1.70 short times with these and drag radials way back when. I prob wont add anymore chassic stiffening unitil if and when I ever put a cage in it. Ill post up pics when I can. Take care.
And the side version SFCs actually attach to the rear LCA mounts which is not really the rear subframe, just close to it. And are really only attaching to 1 flimsy LCA mount wall, not even both mounts.

So in reality? They attach to the front subframe & don't really attach to the cars actual rear subframe. They do serve their intended purpose pretty good, but "technically" they do not actually connect both subframes together.
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Old 11-30-2012, 11:44 AM
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Re: SFC comparison thread

Originally Posted by BlackenedBird View Post
And the side version SFCs actually attach to the rear LCA mounts which is not really the rear subframe, just close to it. And are really only attaching to 1 flimsy LCA mount wall, not even both mounts.

So in reality? They attach to the front subframe & don't really attach to the cars actual rear subframe. They do serve their intended purpose pretty good, but "technically" they do not actually connect both subframes together.
The S&W SFC's i think tied all of that together, as well as a lateral brace underneath the car (under the exhaust and driveshaft). They would not have designed that system for nothing? That is why I think combining the inners and outer SFC's are a good idea, as well as even adding bracing between the rear subframe and LCA thin mount at the rear, and add a lateral brace connecting both inners, and possibly both inners to outers as well mid-length. Might sound a bit overkill but in these cars the frame is so twisty it might actually benefit from all this bracing.. Also the tunnel in between the front subframe (such as the kenny brown brace) would help as well.
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Old 12-11-2012, 12:13 PM
  #171  
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Re: SFC comparison thread

I've only had the Alston SFC's installed on my convertible for over 12 years. No rust or twisting.

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Old 12-11-2012, 12:18 PM
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Re: SFC comparison thread

Originally Posted by L695speed View Post
I just found the horror thread from 2004 with the group purchase batch. Where the passenger front cup didn't fit. People had to do all kinds of crazy things to get them to fit. Including sending them back to Alston. Has this problem been resolved?

Install the front cup first. If you install the rear first you may have it set too far to the rear, guess what will happen? The angle will be wrong. I wonder why?

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Old 02-02-2013, 07:55 AM
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Re: SFC comparison thread

ready to purchase mine now and i want the alstons first but i cant find a place to buy them online, if anyone knows where to get them please post a link, thank you
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Old 02-02-2013, 10:25 AM
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Re: SFC comparison thread

Originally Posted by FlippindaBird View Post
ready to purchase mine now and i want the alstons first but i cant find a place to buy them online, if anyone knows where to get them please post a link, thank you
http://www.top-downsolutions.com/cha...8aka-f-body%29
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Old 02-02-2013, 12:48 PM
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Re: SFC comparison thread

Originally Posted by BlackenedBird View Post
Yep.

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Old 02-12-2013, 10:41 PM
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Re: SFC comparison thread

Alstons all the way, should have done mine sooner.
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Old 02-17-2013, 12:45 PM
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Re: SFC comparison thread

Originally Posted by Twin_Turbo View Post
You are really missing out, the inners truly connect the 2 subframes directly, the outers do not.
Then explain to me why my car teeter tottered on a curb without chassis twist and pulled a cdocumented 1.07 g's on a skidpad with just Spohn SFC's?

Id like to see anyone here put up any ACTUAL test findings that better those proof results with just Alston SFC's- not going to happen. I rest my case.

Any of you with just Alstons can do a simple test. Back your RR wheel up onto a standard height residential curb and see if you can tetter totter your chassis back and forth bringing the RF wheel off and then the LR wheel off the ground. I'd really like to see a picture of that with just inner sytle SFC's. Your chassis will twist and the wheels will not tetter totter. That same twist will happen when you are under cornering load.

I put up proof- lets see someone else do it.

You guys are all looking ar the underneath of the chassis subframes like they are in 2D form. That is where you are wrong TwinTurbo. That rear LCA point is plenty strong in rigidity to the rear chassis section and my picture proves it. You keep caring how it "looks" and I'll keep caring how it actually functions.

Last edited by SlickTrackGod; 02-17-2013 at 12:49 PM.
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Old 02-17-2013, 01:28 PM
  #178  
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Re: SFC comparison thread

All the commercial SFCs tie into either the rear lca or inner subframe so the real difference is not there. The twisting occurs due to the center section of the floor only having sheet metal and the rocker boxes being too weak to resist torsional distortion. Connecting the subframes eliminates apart of the problem. Welding the spohns to the pinchweld attributes the rocker aeea. That still doesn't mean they triangulate anything.

Another prob is that 3rd gen subframes go towards the center of the car like an hour glass which makes that area prone to torsional deflection. The spohns don't do anything for that.

Easy way to quantify results is to put the car on jackstands and start jacking and see how much it takes to lift the other side off the stand. Adding a large level across the fenders and noting the degrees is a good idea also. I used this method and a karge baEam across the chassis to quantufy the design of my cage design on my 82 corvette. I'm not new to frame design, stiffness and triangulation to add as much stiffness with as little bars as possible.
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Old 02-17-2013, 01:52 PM
  #179  
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Re: SFC comparison thread

The outer style does trangulate to the tunnel and ladderbar constructs it with both the already existing front lateral unibody beams as wel as the added trangular tubular beams. I incremnet welded my traingular beams to the florboard sheetmetal as well when I installed mine.

As for checking chassis rigidity by simply jacking the frame to check deflection, that is artificial load. The wheel contact patches are what put load into the chassis-hence why trying to distrot the chassis by driving one wheel up onto something is the best form of checking deflection.
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Old 02-17-2013, 02:33 PM
  #180  
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Re: SFC comparison thread

How does it triangulate? There are only 2 beams, 1 lengthwise and 1 perpendicular

Jacking up under the arm does not side load the lower arm but it does corner load the chassis and torsional stiffness does effect how much the front end will twist before tge jacking load raises the other side off the stand. It's the easiest way for a home builder to quantify improvements. Not absolute but relative. Better than nothing.

Because of my personal opinion I buit these

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Old 02-17-2013, 02:52 PM
  #181  
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Re: SFC comparison thread

yellow is the triangulation. This ties into the full ladderbar construction to make ittriangulated for 2 dimentional rigidity. The yellow also ties intot he purple to keep the purple from twisting. Increments along the pruple also keep the purple from twisting and well as the both help shear panel the floorboard.

Now lets look at 3D form and the vertical lateral shear walls (the rear seat panel, and the firewall panel. Each of these red trangulated ladderbar construction panels tie directly into inner and outer points of both fore and aft lateral shear panels of the chassis.
Attached Thumbnails SFC comparison thread-capture7.jpg  
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Old 02-21-2013, 02:12 PM
  #182  
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Re: SFC comparison thread

I'm pleased to see that TDS has dropped the price of the Alston inners to a more competitive $196. It's this simple thing that gets me saving up to place an order. Better for TDS to sell 3 sets at $5 profit per set than to sell 1 set at $10 profit per set. Making my own Spohn-style outers was easy. Making copies of the Alston or Mac inners isn't so easy. The next challenge will be tying the 2 sets together.
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Old 02-23-2013, 10:08 AM
  #183  
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Re: SFC comparison thread

Atilla, do you have pics of your "Spohn Style Outers" ?
i would like to build UMI style outers, i like the way they support the RLCA mounts, but ill probably just buy them lol
got my Alstons for $200 shipped BNIB from a TGO member
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Old 03-05-2013, 04:53 PM
  #184  
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Re: SFC comparison thread

I'm having the frame shop weld in my Spohn outers as we speak. I can't wait to see the difference they make.
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Old 03-08-2013, 09:03 PM
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Re: SFC comparison thread

Just had my Spohn SFC's installed...The car feels SO much better. Lots of the squeaks and rattles are gone, not all of course, but the car feels solid over bumps. It just feels like a regular car and not one that is about to fall apart.

I had the bare metal ones installed so I need to get under there and paint them ASAP. Any recommendations on what kind and how much paint to use on them? Ideally I'd use an old fashioned brush so I don't have to tape and spray, plus I don't have the clearance to spray. I'm going to do them red. Thoughts?
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Old 03-08-2013, 09:13 PM
  #186  
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Re: SFC comparison thread

Nevermind my question...Just read above and I'll get the POR-15 metal ready & paint.
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Old 03-09-2013, 08:28 PM
  #187  
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Re: SFC comparison thread

Ok, do the top down solution Alston connectors are inners. That tie both true frames together right? Or am I way off? I'm making my car a targa and need the sturdiest type connectors.
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Old 03-09-2013, 08:40 PM
  #188  
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Re: SFC comparison thread

Why don't you go both?
Nothing is perfect anyway.
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Old 03-09-2013, 08:45 PM
  #189  
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Re: SFC comparison thread

Well I plan it. But right now I'm budgeted on just one set. I'm thinking the Alston ones will be too much shipped for me. Well actually they are out of stock anyway.
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Old 03-09-2013, 08:46 PM
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Re: SFC comparison thread

Originally Posted by MY87T/A View Post
Ok, do the top down solution Alston connectors are inners. That tie both true frames together right? Or am I way off? I'm making my car a targa and need the sturdiest type connectors.
Correct. The Alstons are the only TRUE subframe connectors in that all the others only connect to the front subframe. None of the outer sfcs actually connect to the real rear subframe. Most connect to the rear lower control arm mount which is close to the rear subframe, but none actually connect to it.

For a targa top, I'd do both plus see about adding even more bracing.

Last edited by BlackenedBird; 03-09-2013 at 08:51 PM.
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Old 03-09-2013, 08:51 PM
  #191  
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Re: SFC comparison thread

Ok glad to know I was right. Well since there out of stock. I'll be getting umi ones from summit. Is there anyway to tie them into the actual subframe?
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Old 03-17-2013, 10:49 AM
  #192  
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Re: SFC comparison thread

Heads up, Found the Mac inners at a ridiculously low price $133 shipped and insured.
Here's the link
http://www.ws6project.com/user_stor/...owder-coated-/

Last edited by Joe Tag; 03-18-2013 at 08:27 AM. Reason: No response & typo
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Old 04-04-2013, 09:33 AM
  #193  
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Re: SFC comparison thread

Originally Posted by SCCAjunkie View Post
Anyone know why these are listed as 86-92? I have an 84 Z28, so I'm wondering if there's a fitment issue...

http://www.macperformance.com/store/...Product_ID=434
Seems like that is a great deal, and I need inners due to my exhaust system.

http://www.ws6project.com/user_stor/...owder-coated-/

However, I have an 83. Will these really not work on pre-86 cars? I didn't see this question answered yet... maybe I missed it.
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Old 04-04-2013, 10:38 AM
  #194  
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Re: SFC comparison thread

Be forewarned, MAC has a backorder for 3 weeks when I posted that. No one had them in stock. But a great deal if you can wait on them. I wound up getting Alstons from lonsal on here because I was pressed for time. Paid $100 more, but time is money.

EDIT: AND DON"T GET THEM FROM CUNDNRACING ON EBAY, HE HAS 4 IN STOCK LISTED BUT REALLY HAS NONE, AND WONT RETURN YOUR MONEY OR CANCEL SALE UNTIL YOU ASK FOR IT.

Last edited by Joe Tag; 04-04-2013 at 10:43 AM. Reason: additional info
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Old 04-11-2013, 01:47 AM
  #195  
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"will"??? rth gen sfcs fit our cars? I believe they are spohn...just wondering, a guy wants 100 for the set bnib... Thx


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Old 04-11-2013, 10:28 AM
  #196  
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Re: SFC comparison thread

I ended up getting the Spohn SFC's, bare metal. Had them welded on as per instructions on the Spohn website (they had great pictures and instructions). When I got the car back I picked up a can of RedRustoleum and painted it with a brush - It actually came out great.
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Old 04-11-2013, 09:14 PM
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Re: SFC comparison thread

Originally Posted by my3rd View Post
"will"??? rth gen sfcs fit our cars?
No. do a search.
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Old 06-26-2013, 05:19 PM
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Re: SFC comparison thread

whats the best sfc to use on a stock exhaust
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Old 08-25-2013, 09:31 AM
  #199  
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Re: SFC comparison thread

I am with ASE doc Post # 154, I installed South Side Machine SFC back in 1996, they bolt in the rear and are weld in also, I painted them black and have not had a rust issue since install. They tuck up nice and don't hang down, they really tightened up the car.
They did not cost much I don't think they are available anymore though.

I used a GM Wonder Bar up front to tie the front Subframe together.

Kenny Brown makes or did make a nice brace to ie the rear part of the sub frame near the trans tunnel together.
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Old 09-05-2013, 11:24 AM
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Re: SFC comparison thread

This thread really has a wealth of information, although there are some contradictory statements about whether inner or outer style SFCs would be better and there's no final verdict on that it seems. Gotta run both then! xD

Originally Posted by JamesC View Post
So these are stitch welded to the rocker panels/floor boards as well I take it, but isn't there a disadvantage of not having them connect to the front subframes (along the tranny tunnel) at all??
I could imagine that making quite a difference in lateral torsional stability?

Originally Posted by hellz_wings View Post
While we're on the subject of frame re-inforcement, I always liked the idea of a roll cage stiffening the roof of the car, but I never liked the fact that it becomes a nuisance and part of the interior (effectively preventing access to back seats, it looks ugly IMO, etc.)

I was thinking of having a completely hidden roll bar-like tube that hides underneath the trim panels and headliner and ties in to the roof and the b-pillars via stitch welds (like the outer SFC's do along the rocker), which then ties into the rocker and outer SFC (through the compartment behind the sail panel), and then run another bar to the rear subframe to further re-inforce it.. This would probably be more beneficial to guys with t-top cars who want to have a roof as strong as a hardtop, have the safety of a roll bar above you in case of a roll over, but still retain stock looking interior, while hiding this re-inforcement. I know it sounds a bit lol
hehe, i was thinking about that as well, but no clue if it's implementable in that way..
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