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Question says it all. Looking for basic stiffening, nothing fancy. Not a serious racer here, occasional AutoX and dragstrip on street tires.

MM subs seem to be a pain to weld up from what I hear, the Steedas look a bit easier to install. Are they good or junk?

Thanks.
 

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I would get a set of better ones and pay to weld them in. Just driving on a regular road is enough to justify a good set. They are a cheap part w/ cheap installation. Buy a decent set, your mustang will be a nicer car for it.
The whole thing about sub-frames is that the bond between the part and the car is what really matters. Welding them in is so much stronger than simply bolting the parts together. I would put any bolt in model in the less then desirable pile.

I would steer you towards Kenny Brown (aka Ford Motorsport Subframes) ones if you are not super serious, MM if you are.
 

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jfranci3 said:
The whole thing about sub-frames is that the bond between the part and the car is what really matters. Welding them in is so much stronger than simply bolting the parts together. I would put any bolt in model in the less then desirable pile.
All Steeda subframe connectors are weld-in. ('79-93 can be bolted or welded). We have three options for your '01. They are all weld-in.
 

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techguy said:
All Steeda subframe connectors are weld-in. ('79-93 can be bolted or welded). We have three options for your '01. They are all weld-in.
do steeda subframe connector's still only connect at the very end of the front subframe?
 

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Don't do it half-ass. One day you might want to get more serious, and then you'll be kicking yourself as you have to remove them Spend the $150 for the MM full lengths.
 

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I have the MM FL connectors on my car and they weren't any more difficult to weld up than any other SFC.

My brother has the Steeda connectors on his '95 GT which where welded in by Steeda. Next week we will be cutting them off to put in some MM units. I think that the MM units are better. His stick down farther, the MM units make more contact than the Steeda ones, and the MM units are full length. I dont like the rear mount on the Steeda connectors either. I had to jack on the the rear of the connector one and could see the floor pan flex a little. The rear floor pan doesn't seem to be a strong mounting point. The MM units go back to the lower torque box.

Another thing to consider, do you plan to get a torque arm in the future? Most torque arms connect to the subframe connectors. Just something to think about for the future.
 

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94Z28 said:
do steeda subframe connector's still only connect at the very end of the front subframe?
The round tube connectors attach about mid-way down the front subframe, immediately behind the transmission crossmenber (up untill '99 when they changed the crossmenber).

The rectangular tube connectors extend forward about 10 more inches.
 

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OK, here it is....I propose that in torsional twisting moment, the tubular connectors are better than the box type. The box type will fold when twisted, HOWEVER, in the bending plane, I feel that they are better, and it is possible that due to the larger contact area make the car feel better.

In other words, if the points at which the Steeda's are welded is strong enough, then they should be better.

Also, the torque arm issue gets in there if you have any future plans.

If you would like to argue this...Anti sway bars and torsion bars are round...and often tubular, what do they have to do all their life? Twist.
 

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and I maintain that subframes function very little by themselves to improve torsional stiffness of the chassis. However, they do help triangulate the existing structure further, and by being put in compression and tension loads along the long dimension of the connectors, they help the front and rear portions of the car stay fixed in relation to one another. With the weak point between the subframes in the stock configuration, you have an upside-down V-shaped effective structure in the middle of the car. The subs tie the ends of the V and turn it into a triangle, a structurally superior geometry that will resist deformation. It is this structure that will add torsional stiffness, not the torsional stiffness contribution of a long bar randomly welded to the chassis.

Following this logic, the shape of the subs will make little difference under compression and tension forces. Square connectors will be easier to mount to the square subframes, and will be easier to jack from if need be.

I'm ordering my MM FLSFC's next week :)

And dear god, what is engineering college doing to me???
 

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I would steer you towards Kenny Brown (aka Ford Motorsport Subframes)
No offense, but I have never seen ANY round tube subframe connectors from Kenny Brown ever. Ford Motorsport part numbers M-5478-B and D are round tube. The only square tube connector is M-5478-J, and it looks more like most generic square tube connectors out there offered by most people. Kenny Brown super subs dont look much different from Steeda, MM's or anyone else's Square tube connector with cross braces.

Tony
 

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liar! hehe

Troublemaker357 said:
Kenny Brown super subs dont look much different from Steeda, MM's or anyone else's Square tube connector with cross braces.
Check out one of my old threads here.
sn8kbit said:
For referenece, Kb on the left, MM on the right. On a "street" car they may be neat!, do it right the first time with the MM ones:

:) :cool: ;)
 

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Get full length weld in subframes with cross bracing and forget about it. Spend now or spend later. Global West also makes excellent subframes.
 

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I still haven't put subframe connectors on my cars, those little things seem like more of a weight penalty than anything.

Now a beam the size of that bulkhead running across under the rear seat of a late Mustang, that looks substantial, and functional.

What I've observed working on Mustangs, is the front and rear structure is tied together, just not directly down the center underneath where you can see it. The front rail and apron structures tie into the cowl area, which ties into the rocker panel "beams" (pull up the carpets and look) , which tie into the rear wheel house structure and torque box area. Yes it flexes more than it should thanks to 20+ year old basic design, but are a few pieces of metal tubing going to make a significant change to a structure with a 500 lb engine trans hanging at one end and a differential housing/ fuel tank hanging on the other?

A torque arm install is a different set of circumstances.

Someone please convince me under car connectors are not just a weight penalty.

PJ
 

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RagingGrandpa said:
...It is this structure that will add torsional stiffness, not the torsional stiffness contribution of a long bar randomly welded to the chassis.....
;)
 

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RagingGrandpa:

Using the inverted V structure, where did the rocker panels go in your example? Those look like a base to me.

I'm not sure I agree with the "weak area between the subframes" idea, considering the size of the driveshaft tunnel and rocker panels along side. Just looking at the parts, I get the impression that the floorpan is a supporting component, but fairly insignificant compared to the scale of the cowl, pillars, rockers and roof structure.

Now, how about measuring some deflection before and after those MM subframes? Nothing like hard data. (I need more convincing.)


PJ
 

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Good idea! I've got a dial indicator coming in the mail anyways...

Where should I apply load from to cause deflection through? Hrm.... put on jackstands and put a few hundred pounds of ballast in the rear footwells and measure vertical deflection... from the seat mountng bolts perhaps?

I seriously would be interested in taking data considering I'm going to put in the subs sometime in the next few months.
 

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I'm thinking about deflection at the front and rear ends of the car....

Maybe take a base line height parked on a smooth surface at 4 corners of the rocker panels, then additional height measurements at the 4 outboard ends while the car is parked.
Note the height difference between the center and the ends.

Then, 4 jackstands in the center, add the height of the jackstands etc. measure the outboard ends hanging, less the jackstand height. Ballast shouldn't be necessary, the ends will hang. Compare the height differences.
That would give you..tension?

In my exp. the front end will hang at least an inch lower while hanging, than on the ground.

Now do it all again with SFC 's welded on. Easier said than done.

PJ
 

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I'm sorry but I'm not familiar with everything yet.. What does MM stand for and do they have a website?
 

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