Should I change subframe conn ?

Steel1

Mustang Master
Aug 18, 2017
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Connecticut
My 93GT it has a pair of BBK round tube subframe connectors (no seat brace) that were installed 12 yrs. ago.
Installation is fine and I haven't had any issues with them but lately I've been wondering if I should switch them out
for a set of full length sfc.
Not sure if it would be worth cutting/removing old sfc for new full length ?
Car is just a street cruiser that doesn't get launched but I have recently installed a 393w making good power.
Any opinions/advice appreciated.
 
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Was the car ever a daily driver with them installed?
I had a pair of round non full length subs a long time ago.
They stood off the frame a bit and lacked surface connection welding (since they were round, they could only be welded at the bracket).
The subs were on the car as a daily driver and one day I put a jack stand under the middle of one and crushed it. Seemed water was getting it and rotted it.
The rounds also presented ground clearance issues and I couldn't get a jack under the sub itself leading me to deform the frame rail a bit.

After my experience? I regretfully say yes, I think you should change them to maximum motorsports full length.

The bonus is one day if you goto a torque arm, you are ready.
 
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Was the car ever a daily driver with them installed?
I had a pair of round non full length subs a long time ago.
They stood off the frame a bit and lacked surface connection welding (since they were round, they could only be welded at the bracket).
The subs were on the car as a daily driver and one day I put a jack stand under the middle of one and crushed it. Seemed water was getting it and rotted it.
The rounds also presented ground clearance issues and I couldn't get a jack under the sub itself leading me to deform the frame rail a bit.

After my experience? I regretfully say yes, I think you should change them to maximum motorsports full length.

The bonus is one day if you goto a torque arm, you are ready.
No never a daily since sub frames installed only a nice weather cruiser, they are in perfect shape.
Yes they are only welded at the brackets front end is capped and tubing measures 1.6" o.d.
 
I'd keep it as is. If you want to add significant rigidity, and you can weld, consider addding a jacking rail, and then add some spars to link the main SF connector to the JR.
Funny you mention jacking rails because I was considering this http://www.globalwest.net/915.htmling
to attach to my existing subframes.
I "can" weld it's not pretty but effective..lol
 
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I just finished installing MM long frame connectors under my 88 rag top, and WOW, the improvement in the stiffness is awesome. Doors close and open better than ever before.
DSCN9439a.JPG
DSCN9403.JPG
 
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Thanks for all the replies.
I ended up ordering a set of stifflers jacking rails that I may eventually tie into
existing sfc. I need to straighten pinch welds anyways and will now have nice
jacking points in that area.
 
I like the stuff stifflers makes. I have their trans mount crossmember. That thing is seriously stiff compared to the stock one.
I did Kenny brown jacking rails a while ago and I too had to straighten out the pinch weld.
If your welding skills aren't so great (mine are not), just be careful that metal is all so thin.
 
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