How important are Subframe connectors

**BirdFlewLS1** · 12-20-2007, 05:03 PM

I have a 99 trans am thats pretty much got all the engine and suspension mods i need for now besides subframe connectors and a tower brace for the front struts. my car runs a decent 12.84 @ 107mph using traction control on street tires. just wondering if it would help to use them(sfc) to keep it from twisting resulting in geting a better launch on drag radials without traction control.

**Kup98ss** · 12-20-2007, 05:11 PM

Your car will feal more solid. I'm happy with mine so far.
They keep your car from flexing, and it is noticeable.
Almost night and day.

**Sam Strano** · 12-21-2007, 08:39 AM

I'm going to somewhat disagree here. They are not *necessary*. Are they bad things to have? No, absolutely not. However, if you ask around what you'd find are pretty much two results.

The first is what you see above, when they are added on a stock car, or a car with either stock shocks, or some other poor shocks. Because the shocks are not good, you get a lot of impact harshness transmitted to the unibody that should be damped out. So those folks do see a reduction in 'flex' like the dash shaking and the steering column quivering.

The second: When folks add SFC's after they have make the damping better. These folks report little to no change in the feel of the car becaue they've gotten rid of the quivering by keeping impacts out of the structure more often in the first place.

Now, of course if you are doing something that puts a lot of twist into the car they become more important. That's a judgement call.

Let me add this. It kills me when folks are told they NEED them followed by the recommendation that 2-pts. are fine. They are fine, but these folks believe the car is so flexible that you NEED SFC's, why wouldn't you pony up the not a lot more money for the obviously beefier 3-pts?

I sell SFC's, and am as happy to sell those as anything else, or as anyone else is. The difference it I like to investigate what you need or are trying to do instead of just saying that "we have ____ and it's great!"

**Zapper2003** · 12-25-2007, 07:09 PM

Not hijacking, but I really enjoy how Sam is so straightforward about things like this. It's not that often a shop owner/parts retailer will actually come out and tell you straight up how it is. Appreciate the honesty Sam. I'll be calling you in a week or two.

**Bearcat** · 12-26-2007, 10:02 AM

Hi all,

The point that seems to get overlooked time and time again
is that a properly tuned set of shocks will usually cure most
of the rattles, sqeaks and wheel hop issues that some encounter
with an F-body.

Good shocks usually are a good first step in the right
direction. Next step might be a good set of swaybays.
Then for peace of mind, perhaps a set of SFCs.

I just installed a set of UMI 3 point SFCs.
They are really nice pieces.
They are works of art for that matter.

Do I feel any difference? The truth is no.
Do I really need them? No I don't.
Do I regret buying and installing them? Of course not.
Would I buy them again? Yes.
Why buy them again if I didn't need them? That was the last step towards my suspension goals. I had allready installed shocks, swaybars and springs.

With all that said, I now have a good handling, nice riding daily drivin street car.

.

**Sam Strano** · 12-26-2007, 10:30 AM

Originally Posted by Zapper2003

Not hijacking, but I really enjoy how Sam is so straightforward about things like this. It's not that often a shop owner/parts retailer will actually come out and tell you straight up how it is. Appreciate the honesty Sam. I'll be calling you in a week or two.

I appreciate that, and it stems from being "sold" things I did not actually need in the past as well (things other than auto parts). I just prefer to take the higher road, and that actually makes some folks angry. But in the end, those who know I'm not out to railroad them into a quick sale tend to become repeat customers, and that's better for me in the end.

**aeroengineer** · 12-26-2007, 03:55 PM

I installed a set of UMI 3 pnts last weekend along with a STB that was put on a couple of weeks ago. My experience was this:

- car is definitely stiffer which is mostly noticed over poor and articulated road conditions
- the car's ability to corner is really unchanged
- the steering response to the driver is improved. Before installation and during sweeping turns, I noticed that it was difficult to find a sweet spot in the steering that would maintain a given rate of turn, i.e. I felt like I constantly needed to provide steering input to maintain a given turn rate. After installation, I can input a given turn rate and maintain without readjustment. The biggest benefit to me is that I am able to keep the car at the edge of its handling abilities on a constant basis. The bad side is I have now determined that I need springs, shocks, better/wider tires, and some adjustable rear LCAs in accordance with what Sam faithfully maintains.

- FWIW I do feel the extra weight in the car during acceleration but I can fix that with a few changes in the engine department. However, I am growing increasingly concerned with the added weight as this will ultimately hurt my handling performance. I plan to focus on replacing with Sam's parts due to his weight concious approach e.g. sway bars, springs, etc.

**third_shift|studios** · 12-27-2007, 05:44 AM

SFC's saved the passenger of this car from getting ripped apart by a tree:

R.I.P. "madseason's firehawk"

**Danger731** · 12-27-2007, 06:06 AM

Dayum !

**Sam Strano** · 12-27-2007, 06:46 AM

No, they didn't, at least in IMHO. I agree they helped, but if you look in wrecking yards there are a lot of cars like that not torn in half. There is a lot of metal in the car, and some auxiliary piece doesn't make the structure go from paper to steel in it's ability to resist hits.

That hit wasn't even really on the connector, but right around where they attach to the LCA mounts. And fwiw, the connectors are a good bit inboard. If we could get pics of under the car I'd bet you'd find the intrusion might not have even gotten to the SFC rail. Maybe, but it if did, it didn't by much.

**9t8z28** · 12-28-2007, 09:28 AM

Originally Posted by third_shift|studios

SFC's saved the passenger of this car from getting ripped apart by a tree:

R.I.P. "madseason's firehawk"

I was in an accident with my F-body. I was hit directly on the front left wheel. The wheel came back and went directly into the floor board/frame where my feet were. If I had subframe connectors on the car, my feet would not have been crushed!

**Sam Strano** · 12-28-2007, 11:14 AM

I have to disagree. Again, where was the intrusion relative to the where the SFC's connect? It's a nice thought, but you can't say that's the case. Id like to see the underside of the car, and from what it looks like to me what collapsed was the sheetmetal in front of the pedal box, not the floorpan and frame rail.

Again, SFC's are NOT a bad idea. If you want 'em, great. If you don't, don't think you absolutely must have them, you don't. There are reasons, but in both of these cases it's my opinion the SFC's or lack thereof just wasn't an issue.

**9t8z28** · 12-28-2007, 12:34 PM

Originally Posted by Sam Strano

I have to disagree. Again, where was the intrusion relative to the where the SFC's connect? It's a nice thought, but you can't say that's the case. Id like to see the underside of the car, and from what it looks like to me what collapsed was the sheetmetal in front of the pedal box, not the floorpan and frame rail.

Again, SFC's are NOT a bad idea. If you want 'em, great. If you don't, don't think you absolutely must have them, you don't. There are reasons, but in both of these cases it's my opinion the SFC's or lack thereof just wasn't an issue.

Thats O.K. that you disagree. You don't know what the underside of the car looks like, but I do! I have the car completely stripped and "IF" subframe connectors were installed, my feet would not have been crushed. The wheel pushed back right at the main part of the frame. The frame calapsed before the firewall did.

Smash one up like I did and you will wish you had em'!