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FFCobra Craftsman
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Discussion Starter #1
While we were putting in the new rear to get ready for supercharger HP (Superior 31-spline axles, FMS 355's, Auburn Pro Limited Slip, TA pre-loaded cover) we discovered a neat trick for a rear sway bar.

We had a used rear sway bar from a GT Mustang hanging around. While the Cobra was on the lift, we bolted that sucker up. Of course it hung down like Auntie Ethyl's boobs. We put a tall transmission screw jack under each corner of the bar and screwed them up until the rear of the car was actually off the lift slightly. Then we put heat to each side of the bar at the first bend after the mounting bolts. As the bar bent up we, screwed the jacks up further, each side a little bit at a time. In about 5 min we had a custom bend sway bar with plenty of ground clearence.

Process worked great and the sway bar actually makes a big difference in handlng. Total cost was $30 for the sway bar.

Frank.
 

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FFCobra Craftsman
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Discussion Starter #3
Bill - I'll have the Cobra up on jack stands later in the week and will try to take a few pics then, but they are not really needed. Once you have the car up on a regular lift and bolt up the stock bar to the lower control arms you can see exactly how to do it. Just be careful with the torch - make sure you have the flame pointing away from the tires and not at anything that will burn. Also remember that the gas tank is only a couple of feet away. If you have another person watching you, it is a gkood safety thing. Whole process took about 5 min.

Frank.
 

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Senior Charter Member
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Hi Frank and Sons,
I was wondering if you have coilovers or the Mustang's springs? I put my sway bars back on but they are so low that they actually drag on real tight turns. I have FFR coilovers. Inman Lanier was going to get back to me about a guy that makes higher bars for our cars in Lake Worth.

Thanks,
Ron FFR1738
 

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The stock rear sway-bar hangs low on the FFR because of the FFR supplied brackets that relocate the lower control arms. I ran the stock rear bar on FFR1190 with no problems.

Heating steel to bend it will reduce it's strength. In theory, it should be heat-treated after bending. What could happen is, instead of the bar acting as a spring, the bar could simply bend as the suspension moves. You are probably fine though. Just be aware of this fact.

craig
 

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FFCobra Craftsman
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Discussion Starter #7
CobraEarl - I thing the Mustang suspension is simply mounted higher plus the way the LCA mount on the FFR angles everything down.

Ron - we are using stock sn95 Mustang springs and Gripp lower control arms (Autoweld uppers).

Craig - you made me lose a $5 bet to Adam (part of the "Sons" part of Frank n Sons). He said someone would write about not putting heat to suspension parts. Yeah, we thought about that and figured "what the hell..." We are not talking about a lot of heat here at a small spot. It was spread out over a couple of inches (about an inch each side of the first bend in the bar). Worst case scenario is that it bends. So far (we have about 200 miles on it now with some pretty good bumps included) it looks perfect and there is absolutely no doubt that it has improved ride and handling. Steering actually seems to be easier (less twitch) and if you hit a good-sized bump with one of the rear wheels, the rear does not wander.

For $30 bucks total cost, I do not see a down side and this was one of Adam's idea (of which, I am always critical).

Frank.
 

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since a sway bar works by its torsional resistance, and this constant is raised to the 4th power to calculate a wheel rate (and affected by the temper of the metal), you may experience significantly different rates than before the heating. they may also be different from side to side. as long as you dont get near the limits of the car (which one should never do on the street anyway) it shouldnt be a problem.

i cant remember if you have a 4 link or not, but the rear roll stiffness is very non-linear in compression. ouch!

-james
 

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FFCobra Craftsman
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Discussion Starter #9
James - the torsion is across the length of the bar. The part that was heated is within a couple of inches of the mounts and way before the 90 degree horizontal bend. I suspect that nothing has changed. What I can tell you (and we did some rigorous testing last night) is that it is an absolute improvement in ride and handling.

Frank.
 

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Senior Charter Member
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For those interested in gaining extra clearance for the sway bar, there is an alternative to heating the bar and bending it.

Each end of the sway bar is a flat on edge with 2 holes drilled through it. Simply weld a triangular shaped flat bar on edge to the bottom edge of the flats of the sway bar. The point of the triangle should face forward.

Attach the sway bar using only the two front bolts. Now, pivot the bar up and mark the flat piece for a new bolt hole using the bolt hole in the control arm.

Drill the holes and bolt up the bar. Presto, a sway bar that up out of harms way. Looks better as well.

All the best,
Bob
 

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The heat from welding won't reach the round section of the bar to sufficiently alter the torsional integrity. This would prove particularly true if one welds short beads with cool off periods in between until the beading is complete ;) .

All the best,
Bob
 

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In Bob's solution the heating is all done at the mounting end, not on the part that is placed in torsion. It's the least critical part of the bar, and a pretty good solution.
 

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FFCobra Craftsman
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Discussion Starter #15
Now why didn't I think of that? I think either process will get you there.

Frank.
 

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John,

Is it likely that you were posting simultaneously with yours truly?

BTW, it helps when slow are tutored by the quick. Thanks again.

All the best,
Bob
 

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Bob,

Quite likely. I'm still trying to be quick though. Six weeks and I'm still not racing! I think she's in a snit over going agricultural at Shannonville, and won't let me play again until I replace every bit of the driveline, one piece at at time. I'm ready to hurt the next guy that breaks a delivery promise. And only one week left until we leave for Bay Bottom.

Regards,
Nervous John
 

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Administrator
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A stock rear sway bar on the standard FFR rear suspension is generally NOT a good idea. Especially if you are running anywhere near stock front spring rates.

It may feel more responsive, but the car will come around on you before you can say "OOPS" if its pushed anywhere near the limits, or put in an emergency corrective situation.

However, it may be a good idea on a 3 link car with 550+ front springs and 250 rear coil overs or stock rear springs.

David
 

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I'm inclined to agree with David. And I'll take this opportunity to issue another rant on suspension setup. If you're interested it will be posted under "So you want to race that thing?"
 

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OK, you've got a good point. So let me ask you a different question. I'm still in the planning stages and I don't ever plan to race. There is a remote possibility that I will choose to do an autocross or maybe a pass at the drag strip, but this will not be the main focus. I would like my car to handle nicely and "feel" fun on the freeway on-ramps.

I just recently installed a panhard bar on my Mustang (along with new lower control arms) and I'm very pleased with the feel. I had planned on getting the 3-link option from the start, but the 4 link would probably not be as sloppy on a lighter car.

Anyway, what setup would you guys recommend for a nice, fun "feeling" street car that might see one or two autocrosses? I want it to be safe, but I also want it to "feel" fun, but it doesn't actually have to be fast. Just completely stock 4 link? 3-link? IRS (more $$ than I wanted)?
 
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