subframe connectors

[rwinter]

Hi

I have a 2000 firehawk with t-tops and hardly any mods as near as I can tell. I read somewhere that if I drive it hard the unibody will flex and pretty soon my t-tops will leak due to body distortion! Is this true with a unmodified engine?

Do I need to rush out and get subframe connectors asap? Yes, I do want to drive it hard!

Any other mods I need to do to make it last?

Thanks for any tips.

[sunsetorangess]

Sub frame connectors are a good thing on a t top car. Its will keep the un-sightly dimples from forming over the rear fender wells. It will also keep the car inline when your doing those high speed cornings and when you launch it will keep the body flex too a minimal. I also recommend getting a strut tower bar. It will make a big difference. As far as modding goes just use common sense and you will be good to go, Dont do a cam with a stock intake kinda deal.
If your gonna get sfc try and get the weld in type, and if you get the boxed sfc you will loose about 1/2 ground cleareance. On a stock ride height its not much of a difference.
"boxed" is suppose too be stronger" than the tubed.
J

[rwinter]

Thanks a lot. I think I can feel the car flex on a up shift. What brand connectors do you suggest?

How many miles does it typically take to see the dimples? I'm sure mileage varies but trying to get a feel for whether its a 100k miles plus type problem.

How did the strut bar help? On some cars those can make the car develop a push, or understeer. Did you notice that?

[NHRAMAN]

3-point are best...weld them in.

[Frozen WS6]

I have a friend that just picked up a 15,000 mile one owner 2000 WS6 and the dimples have already started. I've told them and shown them about the dimples on my 01 WS6 with 63,000 miles. So they are ordering frame connectors soon also.

[6sw00]

where do these dimples show?

[Frozen WS6]

The dimples will be on the quarter panel. Just behind were the painted roof bar/ sail panel, meets the quarter panel and the front lower corner of the hatch glass. My friend's 30,000 mile SS that he had ordered with sfc's already installed on his car from slp, one owner, isn't as bad as mine, but there still there. I've got 60,000 miles without them. I bought it with 51,000 miles. Yes, it had an unedjucated previous owner that didn't know they were needed. I have yet to see an F Body that didn't have even a little dimple. But then again, our road system takes it's toll on everything. My opinion, all F Bodys need them, all the way back to 1967. I even put them on my 74 camaro, and a 69 camaro with a 540 inch b.b. we built for our fastest street car drag races.

[tonyjnjz]

so right behind the ttops right? hum..sub frames SOOON!!!!

[Frozen WS6]

No. If you look down the quarter panel behind the door on the top, maybe an inch long, down from the edge, and the bottom corner of the back window. I'll get a picture up soon.

[tonyjnjz]

ahh alright..i got ya...well i have that very very slight bubbling on the piece behind the ttops...my 99z had it as well...does this get REAL bad for ppl that drive there car in winter and what not? ..i dont even drive mine in rain but i was just curious how commen this is and how bad it can get

[Hurley711]

SFC & lid should be the first 2 mods for our cars....This should be a sticky. Hmmmm.. anyone?

[Frozen WS6]

It looks like I may have confused a few people with the location of the dimples. Here are a few pics. Look at the light reflection and notice the wave. I hope this helps. It is not bubbling and is not the panel behind the t-tops. It is on the quarter panel. Also it has nothing to do with driving a car in the winter or rain. It has to do with the body/chassis flexing, due to the lack of structural integrity. Twisting of the chassis from driving hard through corners, drag racing, or even flexing when entering a driveway at an angle.
7653

7654

[onyx_rock]

ahh alright..i got ya...well i have that very very slight bubbling on the piece behind the ttops...my 99z had it as well...does this get REAL bad for ppl that drive there car in winter and what not? ..i dont even drive mine in rain but i was just curious how commen this is and how bad it can get

that sounds like the paint bubbling problem i have read about here. it is supposed to be covered by warranty.

[6sw00]

my dimples arent there.. mine look to be right above the wheel.

[Frozen WS6]

I believe that the location of the dimples will be directly related to how the car was driven, and how the car has flexed because of it. Whether it was street raced, driven hard through corners, or just babied. They seem to twist even more if it was ran hard with the t-tops off a lot. Especially since the glass is such a part of the structure of the vehicles these days.

[GUSHER]

Bmr Welds Works Great On Mine !

[firesilver]

Well i have dimples right above my wheels too. I think sfc just moved to the top of my list.

[Frozen WS6]

Like Hurley 711 said, and I agree. SFC's should be at the top of everyone's list of things to do to their car first.

[amon37]

I just bought my ws6 only 25k miles and no dimples yet 2 weeks ago. I know it wasn't driven hard but I will be ordering SFC's within the week because I know I will do some spirited driving here and there.

[Frozen WS6]

I hope we could get one of the moderators to make this thread a sticky, so it doesn't get lost. Alot of members could benefit from reading this.

[Fastcar]

I have UMI Performance bolt-in tubular SFCs, rear lower control arms, and their non-adjustable Panhard rod bar. Up front I have a Hotchkis strut tower brace. The difference in handling, feel, and "tightness" of the car after these mods is AMAZING! The car doesn't creak and rattle any more on bumpy roads, when you hit a bump or pothole the whole car doesn't shake, just the one wheel reacts to the road imperfection. The whole car feels more structurally sound (as it should)! GM should have built the car with the extra reinforcements right from the factory! (But we know why the cheap cost-cutting a**es didn't.) BTW, replace your sway bar bushings and end links with polyurethane parts from Energy Suspension. (Forgive me Ed for naming names...) UMI will powder coat your components in custom colors for a small additional charge. :burnout:

[Y2KPewterSS]

SFC & lid should be the first 2 mods for our cars....This should be a sticky. Hmmmm.. anyone?

Excellent advice! :yup:

[GMS Fleet]

GP on subframe connectors :yup:
http://www.ls1.com/forums/showthread.php?t=33711

Whether or not you decide to join the GP I'd highly recommend weld-in subframes. Better safe than sorry.

[Pro50gt]

If you get the bolt-in SFC's are all the holes already there? How much better are the weld-in type?

[whs]

If you get the bolt-in SFC's are all the holes already there? How much better are the weld-in type?

Most people claim that the weld in connectors are better, the bolt in connectors use existing holes in the factory subframes and rear control arm brackets. They come with the backing plates and bolts.

I recently purchased a set of SLP's weld in subframe connectors. They aren't powdercoated like the bolt in connecters, but they have the holes in them like the bolt in connecters. They line up with holes in the subframes and would bolt in just fine.

The last time my car was in the body shop their opinion was that bolt in connectors were okay, and recommended against welding on the subframes. Everyone is probably going to have a different opinion on this.

I asked about using one of those heavy duty epoxies and bolting them in, however I don't know if anyone has done this. My thoughts would be if the glue didn't hold up very well they would be bolted in and could always be welded later.

[Frozen WS6]

:yup: I agree with whs. I've worked at a bodyshop and dragraced for over five years with boltins and had no problems at all. The drag car was a 10 second camaro.

[indiana hawk]

I have an '02 firehawk and just installed sfc's on it. The difference in the ride and handleing is noticeably better. It only took about an hour to install them. I got the UMI two point bolt on's; they're cheaper than 3-points and that's all you need unless you are installing a tunnel mounted torque arm. If you're keeping your car stock, I suggest the UMI 2-points--they also tuck under your car better.

[Joshua.Grooms]

Are the 3pt that much better than the 2 pt? I know they connect the front to the rear but does it make lateral integrity greater?
Does it ast like a "space-frame" with the additional support or is it just over kill?

[indiana hawk]

The 3-point does add a little more rigidity than the 2-point, but the 3-point can also become a problem when installing a better exhaust system.

[SiggyZ]

SFCs are a must if you want to stiffen up your frame good. I plan to go with BMR boxed and have them welded on.

[Joshua.Grooms]

Ive seen pictures of a car with the 3pt SFC and they look pretty sweet. THe Exhaust was of course heavly modified. It look like a set of Hooker long tubes going into some monster sized freaking under car piping. Not sure if that would be very good to have when going across speed humps(i mean humps not bumbs) going in and out of Army Installations. They always have em.
If i can figure it out, ill put a pic on

[Joshua.Grooms]

Here we go, its by UMI. Is this a good start for looking into SFC?
Right now, having any is better than not having any, huh?
I like how you can bearly see it from the side, nice and tucked in
8659
I like the set up on this car, Really clean
8660

[Frozen WS6]

Josh,
2 points don't do as much for the twisting during hard cornering as the 3 point. Yes, I know that was a very opionionated comment. But that is what my experiances are. I've used both and I prefer the 3 point. Most people that have never done the side by side compairison will not notice any difference between the two. I have SLP's 3 point on my WS6 and have no complaints. My friend has the same ones on his 02 SS also. His has headers and removed cats, and he has no issues with contact anywhere. On t-top cars there is no roof for rigitity or any x-bracing in the floor like the drop tops have to prvent any twisting. Which created the dimples on my quarter panels. Which is what the 3 points will add to your car.

[Joshua.Grooms]

Cool, Well, i was pretty much going to go with the 3pt, but wasnt sure at the time. Its alittle more $$ but From what it sounds like, in the end, its worth it. And It would be a good investment since i will be AutoX and hopfully roadracing again when i come home from Korea. THANK GOD!!

[bluefields88]

I just ordered some bolt-on SLP SFC's. can't wait to see how they'll do. my car creaks every time I go up a driveway.

[Frozen WS6]

You'll like them. That's what I'm using, SLP boltons.

[Joshua.Grooms]

Ok i ve decided that I do want SFC (duh) and STS turbo system. Now the only problem is that, the intake pipe goes were the sfc is. Is there anyway or getting around this other than getting somthing else?
I like the STS system and I want the 3pt SFC setup this car has.

sts system note the intake
8775
SFC by UMI note the main support bar where the intake would go
8776

Any way of working the intake around this?

[bluefields88]

that's a sweet turbo set up right there. but there doesn't look like there's any room. hmmm. quite the dilemma.

[koolaid_kid]

This subject has been greatly debated before. STS claims that the intake acts somewhat like a 2 point SFC (which I suggest is a big crock). They tell you to use the passenger's side only and you will be happy.
There was also another forum member who claimed to have modified his 3 point SLP unit to bypass the intake, but used the rest of the SFC. Unfortunately, he never posted any pics. IIRC, this was on ls1tech.
I was lucky, my LT1 intake goes up the middle of the car, so 2 point SFCs were not an issue.

[bluefields88]

I installed my SLP 3 points today with my brother. it was quite a hassle. the holes that connect to the cross brace were off a little and we had to grind a little on the car to get the back flange to sit flat on the car. it said it should take 2 hours for a professional to do it, but it took us 4 hours. ehhh. we had to use a wrasp to make the bolt hole bigger so the bolt could go in straight for the cross brace.

[tonyjnjz]

more importantly ..hows it feel now???

[Joshua.Grooms]

Did you install it with the car on a drive on lift or a frame lift? Depending on your car and how it has been driven, the car may have already been suffering from body twist.

[bluefields88]

all we had was a jack and some ramps. the car was too low to drive up onto the ramps so we jacked it up and slid them under. we thought maybe one side was higher than the other and causing the body to twist, so we tried jacking one side up higher than the other correct it, which didn't work. my car doesn't have any body dimples and only has 50,000 miles on it, so the body shouldn't be too twisted. and the problem did occur on both sides. but, we did get them on and the car drives alot better. you can really feel the difference going up or down a driveway. the car accelerates alot better to, ever little tap of the pedal can be felt more. it feels like a much more expensive car now. : D

[sobaka79]

Did you install it with the car on a drive on lift or a frame lift? Depending on your car and how it has been driven, the car may have already been suffering from body twist.


this is what is keeping me from getting SFC, ive driven my car hard for 140,000 miles, and im pretty sure im already flexed,

my question is how do i compensate for the flex that is already in the frame before i weld on the SFC?

[Frozen WS6]

Remember, that all the vehicles weight needs to be on the suspension. A frame lift can and will cause the vehicle to flex, thus making the holes misaligned. A quick way to do it, is to use old rims under the tires. I just put my jack stands under the suspension and still had to drill out a couple of holes because of the existing twist. Even my friends one owner 02 SS that he ordered with SLP installed SFC's and 20,000 miles has a dimple starting, and also my other friends 00 WS6 with 15,000 miles has also started. It's the nature of the beast. As far as the turbo piping, I'm not sure. I am a procharger person so I've never had to worry about it.
The only way to correct any twisting of the body will be to put it on a body shop frame rack. Most body shops probably won't do it. Also there are very few people who are good enough to correct it, or that I trust with my car. I would still put them in and atleast get it stopped now before it affects your door, and hatch gaps, and opening and closing.

[sobaka79]

how do i compensate for the flex that is already in the frame before i weld on the SFC?

[Frozen WS6]

You will have to have a bodyshop put it on a frame rack and pull it. They won't ever be able to get it back to original spec. Unfortuneately it will probably end up making it worse. At least thats my experiance after 5 years at a bodyshop. I would just weld them in as is, if it were mine. Thats what I had to do on my 74 camaro also, and my 01 WS6 had 50,000 miles and 2 previous owners before I got it and put 10,000 miles before I was able to put them on. My 01 already had the dimples on the quarters when I installed my SFCs. So I know mine has some twist already in it also. I only had to slot two bolt holes and well worth it.