Subframe connectors for a driver/cruiser, necessary to weld to floor?

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If you set the car up with bigger sway bars, wider stickier rubber, and poly bushings, it will most certainly benefit from subframe connectors keeping the body stiff and forcing that upgraded suspension to do its job. Not everything about these cars involves just a straight line.
It all doesn't matter unless you have traction.
If you read his original post he's only doing smokey burnouts no racing.
 
I would definitely be on the fence about installing them in your car. My old '67 hardtop (440/4sp/3.23SG/no traction) felt just fine without connectors. With the factory big block suspension handling was decent. When all of those parts were transferred to my son's '67 convertible we installed connectors. The convertible definitely needed them. I also have connectors in my Barracuda convertible (440/727), but will not be installing them in the GTS convertible to keep it more original. In a convertible you can feel the difference, a hardtop not as much.
 
The Benefits of better handling will be felt with the connectors

This is a fact. I have two darts and the one with frame tied handles much better on turns. Its like night and day.
Its not all about hooking up and twisting the body. The body will flex and roll while cornering. When this happens your suspension is not doing the work it should.
 
My 1973 is a driver/cruiser, and I like to smoke the tires now and then, no racing.

Is it worth it to simply weld connectors between the subframes without welding to the floor?

Short answer is yes! Good luck.
 
I didn't read where anyone stated "you won't benefit from them". It was stated "you don't NEED them". With a mild motor, I cannot disagree. It isn't a NEED, but you can BENEFIT.

Fast facts
  • No muscle car came from the factory with frame connectors as an option
  • When more support was need with the extra HP, torque boxes were added. Were torque boxes cheaper than frame connectors??? Something to be said there.
  • Even 440 6 pack and Hemi cars did not add them from the factory.
  • Even 440 A-bodies did NOT have frame connectors.
This being said, yes, there are benefits to them, but before we say NEED, you best be talk'n HP, with converter with traction!

who will give the first red X LOL
 
After reading all of the comments I’m definitely wondering whether it is worth it at all. I don’t race and I run a completely stock suspension.
 
I went with the Mancini/non-floor welded connectors after a similar discussion a couple years back, no regrets.

The thing that seems to be missing here is the debate over torque boxes. I have no data to back this up but the Torque boxes may actually be more important since this is what Mopar chose for factory high performance equipped cars.

As has already been pointed out, the factory isn’t the last word and they were working with much lower traction levels due to tires of the day…but it’s hard to imagine that the torque boxes would have been cheaper than the subframe connectors in terms of manufacturing.
 
I didn't read where anyone stated "you won't benefit from them". It was stated "you don't NEED them". With a mild motor, I cannot disagree. It isn't a NEED, but you can BENEFIT.

Fast facts
  • No muscle car came from the factory with frame connectors as an option
  • When more support was need with the extra HP, torque boxes were added. Were torque boxes cheaper than frame connectors??? Something to be said there.
  • Even 440 6 pack and Hemi cars did not add them from the factory.
  • Even 440 A-bodies did NOT have frame connectors.
This being said, yes, there are benefits to them, but before we say NEED, you best be talk'n HP, with converter with traction!

who will give the first red X LOL
Let me be your first green check.
Will a mild engine car with an open diff twist itself into a pretzel??? Or even a pretty hopped up ride with a suregrip be negatively effected? Probably not! Are frame ties "good?" Either in homemade 2x2, or another type. Yes, I believe so. Of course subjective, and "good" can be as beneficial as a fine cnc head job on a bone stock engine. Does it help? Yes. Does it help more, the more is done to the car? Yes.
 
Everybody, let’s not loose the scope of what the original poster is asking about. He doesn’t really need frame connectors. He may want them though.

And there are some great photos of super nice connectors here. Very well thought out. @moparmat2000

@Daves69 2X3 through the floor style work great.


Ouch! You hurt my feelings. I had a lot of fun with that "junk"

didn’t mean any harm, just meant there is no comparing a stock Vega body to a stock Dart body.

hell yeah they can be fun if built right.
 
After reading all of the comments I’m definitely wondering whether it is worth it at all. I don’t race and I run a completely stock suspension.
With all the work involved and you don’t want to disturb the undercoating then this whats left.
 
As so many have already posted, the benefits are dramatic even for a daily driver. I put them in my Demon that does not go to track and the handling was night and day. And personal preference here, I have never welded any of mine to the floor. Including my race car. They are cheap and easy to do with moderate skill. And my opinion one of the best driving improvements you can do for very little cost.
 
Everybody, let’s not loose the scope of what the original poster is asking about. He doesn’t really need frame connectors. He may want them though.

And there are some great photos of super nice connectors here. Very well thought out. @moparmat2000

@Daves69 2X3 through the floor style work great.




didn’t mean any harm, just meant there is no comparing a stock Vega body to a stock Dart body.

hell yeah they can be fun if built right.
All's good. My little Vega started life around 2300 lbs. so you're right, it's hard to compare them with an A body.
I still say you can put quite a jolt into some of these old A bodies it you're cruising along and then decide to downshift and nail the throttle. Especially if the tires don't break loose.
Lol
 
I have not been involved with the "weld to floor" designed connectors. What I gather from the internet is that the weld to floor connectors are cut from channel and get seam welded to the floor. This is a less than desirable design. If the channels had flanges and could be plug welded to the floor with tight tolerance, I would be more inclined to consider that design as equal to or even superior to the square or rectangular tubing. I can see the existing "weld to floor" design tearing out or separating as Brooks James has witnessed. Just an old, burned out Body Man's opinion.
 
I think Chrysler should have finished the frame rails out on every car built from 59 to 76. And yes, I think it's important to tie the floorpans in regardless of what type connectors you use. I don't have them in Vixen yet, but they're comin.
 
After reading all of the comments I’m definitely wondering whether it is worth it at all. I don’t race and I run a completely stock suspension.

Torque boxes might still be something for you to consider. They do stiffen up the chassis, and they can be installed with a fairly small amount of welding. For a fairly small addition, stiffening the corners the way they do does make a difference. I don't think they take the place of subframe connectors, but they are what the factory used for convertibles and higher horsepower cars.
 

The thing that seems to be missing here is the debate over torque boxes. I have no data to back this up but the Torque boxes may actually be more important since this is what Mopar chose for factory high performance equipped cars.
...

Torque boxes might still be something for you to consider. They do stiffen up the chassis, and they can be installed with a fairly small amount of welding. For a fairly small addition, stiffening the corners the way they do does make a difference. I don't think they take the place of subframe connectors, but they are what the factory used for convertibles and higher horsepower cars.

There’s an echo in here. :D

Based on the historical application of these two measures, I think there is a strong case for the OP to use this option. His car sounds like it has been upgraded to at least the level of cars that would have come with this equipment and while it’s not being raced, it’s not being driven like a fragile Model T nor is it being put-putted around to car shows like a *gasp* priceless Hemicuda either.

I guess the problem is that it’s very hard to have real data on how much these things help and therefore very hard to compare one chassis flex countermeasure over another. Nobody is sacrificing their own car to chassis rigidity testing and even if they did, these are all half-century old, used and often abused platforms making control data nigh impossible to come by.

Anecdotally, torque boxes seem to have made a huge difference in preventing chassis twisting/long term damage when big power and slicks were added to the formula…so even without data, I’m pretty confident that they do something helpful.
 
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I have not been involved with the "weld to floor" designed connectors. What I gather from the internet is that the weld to floor connectors are cut from channel and get seam welded to the floor. This is a less than desirable design. If the channels had flanges and could be plug welded to the floor with tight tolerance, I would be more inclined to consider that design as equal to or even superior to the square or rectangular tubing. I can see the existing "weld to floor" design tearing out or separating as Brooks James has witnessed. Just an old, burned out Body Man's opinion.
And that right there is exactly why I do not weld to floor pans. I just was not man enough to open that can of worms in my reply. Kind of like asking what is best cam for my car on here! Thanks BP!
 
I have the Hoskins really nice low profile just welded the ends in I could have gone with the bolts but decided to get them welded in night to day difference in handling . The car feels well planted under power in sweeping curved roads , larger torsion bars are another great up grade as well for a tourer, not so if your using it as a strip car.
 
Do you need them, no. Give you peace of mind...yes. Back in the day, only the big block modified mopar buddies tied the frame. They noticed the door gap had changed. This was after track time with slicks.
 
Instead of welding to the floor you can weld or mount small brackets or angle iron to the bar and then bolt thru the floor in a couple of places on each side. This will tie the floor and connectors together as one and won't start a fire.
 
Vega? WTH?

Scamps and Darts are much better cars that that junk. With a mild small block and street radials it’s not needed. How many thousands of A body mopars are out there without them?
Mine has none.
Running up to 430 hp, and
running 295 Coopers or BFGs, since 1999;
Nothing bad has happened.
But I did weld the front and rear floors together, both sides. And made sure the T-Bar X-member was well secured.
My car 60fts in the 2.2 to 2.4 second range so no hook to speak of, and I don't care, cuz that's not what I built it for. I built it to slide around city streets predictably and uncontrollably, two things that it does very well. It is still wearing the same wheels I installed way back when, altho one of them had to have a chip welded back in, lol.
My advice to a streeter is;
1) to just drive it. The car will tell you when it's time for connectors. and
2) Spend your money on fitting really wide tires on the back, cuz when you are sliding sideways, you just can't have too much patch on the road. I guarantee you that 255s will get you into sideways trouble. This is especially true if you have a hi-compression engine and a manual trans.

Another thread gone sideways, here's a refresher for those who missed the first post;
My 1973 is a driver/cruiser, and I like to smoke the tires now and then, no racing. Originally a 318 car, now a warmed up 360. I'd like to weld in subframe connectors, and I was thinking about fabricating them myself.
I know that ideally the subframe connectors would be welded to the floor, however my undercarriage is coated and I would like to avoid stripping the undercoating, also my interior is fully installed and I don't really want to spend the time removing the seats and carpet. Is it worth it to simply weld connectors between the subframes without welding to the floor?
 
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I have installed several sets of frame connectors. I do have experience with floor welded vs end welded too. I installed the USCartools weld to floor connectors in my 64 Barracuda. Shortly after completing that job a friend wanted connectors in his 64 Barracuda. We fabricated those from 2x3 tubing and they were only welded at the ends. If you were to ride in both cars blindfolded I do not think you could tell the difference.
You would however, notice a before installation and after as soon as you close the door.
 
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