body stiffening

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mopardemon340

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putting 408 stroker in a 72 demon and we are looking for 400 to 500ph... at what HP would you recommend we put a frame connectors in to stiffen it and stop twist.
 
Sub frame ties are in my book mandatory. They are the single most beneficial add on to these cars. The old Mopars have lived in the shadows and been condemned to the age old thought that they handled like shopping carts. This is IN MY OPINION based on the fact that these cars were drastically under sprung in the attempt to make them comfortable to drive. This is why ties are so important. When you increase spring rates it puts even more force on the unibody. You need to stiffen the chassis in order to make the "springs" do the work. If the spring is stiff but the body twists first then your not achieving much.
 
Pretty much they all need them, as well as going over all the welds or even adding gussets on the K-frame. Torque boxes wouldn't hurt either....Mopars have been known to crack paint on the quarters from torque.
 
us tool has a whole package for a bodies , as well as b body stuff . i installed their frame stiffeners n boxing on a 71 340 4spd duster with no issues , but the car was on stands , lol .
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I'll second the u.s.cartool. I've got their stage three kit in progress right now. These guys are first rate and their products are top notch. They are some of the best craftsman I have seen in a long time. As a bonus I think for the quality of the parts you get that they are underpriced....
My two cents...
 
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Where did everyone get there frame connectors? Also, never heard of a torque box. Im a newb. Half way through my first build. Mag swap.
 
no one ever questions frame connectors...they just put them on! and no doubt they will add some strength.
Now i question everything and to me it looks like you are just adding 2 more studs to a stud wall.Triangulating the corners would seem to be more beneficial...just like the torque boxes ma mopar installed.
... nothing so strong as a triangle or gussets
the other thing i wonder about is why strength to the front as well as the rear is rarely considered?
 
i used 2" x 2" square tubing, cut the floorboards once tubing was welded to the sub frames I welded the floor boards to the tubing, it is super stiff. Intrusion into floor boards not a problem.
 
i used 2" x 2" square tubing, cut the floorboards once tubing was welded to the sub frames I welded the floor boards to the tubing, it is super stiff. Intrusion into floor boards not a problem.
intrusion and welding to floorpans is the stiffest way.
 
My original thought was that while the US Car Tool connectors that follow the floor pan are undoubtedly better, this project is a significantly bigger proposition than the bolt in types. Between pulling the interior (to avoid a fire), prepping the surface, modifying the braces to fit, welding them in, this easily could become a very expensive job, assuming you're not a welder yourself.

So...I bought a set of the Mopar Performance bolt-in type which are still in their shipping box. I plan to have them welded in which according to my local shop, shouldn't require anywhere near the prep of the Car Tool type and should offer a lot of the benefit.

What are your experience with these? Should the benefit of connectors be obvious? How do you know they're not working?
 
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