Rear shocks twisting frame?

[sewlow]

That goes against everything I've read in chassis manuals etc. It might not make a tremendous difference on a pick up but I've seen my fair share of rear end collisions on pick-ups and almost always one or both upper bedside corners smack the cab corners below the rear window in a collision. Flexi-flyers.

Race cars and hot rods can use all the stiffness they can get. As already mentioned it makes for more predictable suspension action. I do alot of Mopar stuff and following the Mopar chassis manual of just additional welding to what's already there makes a night and day difference in chassis stiffness without adding a single piece. Add sub-frame connects and torque boxes and really make progress.

Flexi-flyers. Sub-frame connectors.
Considered them for my Nova. Even bought a set. Never installed. Didn't like the way they took away from the stealth look of the car.

On Sunday afternoons, I'd drop by M&D's.
Mooch a meal. Wash my car.
14yo kid next door. Knew from when he was in a stroller. Aspiring gear head.
"CanIhelp,canIhelp,canIhelp?"
"Sure. Wash the wheel wells & the wheels. Tire goop, too."
"All done? Alright, man. Jump in." Go for a drive. Bang off a few gears.
One time we ended up in White Rock. It's right on the ocean. Summer time beach cruisin'.
Spy a '68 GTO. Some competition?
Out to the highway. Standing start 1/4 mile. $100 bill at the other end. (Roll-racing? Mmm...naahhh.)
Goat's got steeper gears. I've got shorter tires.
He gets a 1/2 car off the line. Damn.
But the BBC's just starting to eat. Wait for it.
All through first gear, the kid's hollerin'. "Aahhh...!!!"
Grab 2nd. No lift. Like Grumpy. But without the elbow flapping.
"Get off it! Get off it!"
No way. I'm reelin' him in. Top of 2nd, I'll have him. 3rd.'ll seal the deal.
What I didn't know till later was that when we launched, the kid had had his elbow on top of the door panel, fingers between the top of the window frame & the drip rail. Hanging on.
The Nova's uni-body was flexing so bad that the kid's fingers were getting pinched in there. He couldn't yank them out until the 2-3 shift!
Next weekend, he shows me his fingers. 3 black nails. But he's laughing!
By the next weekend, they'd fallen off.
Think he was kinda proud of them. Showed all his friends.
I reconsidered the sub-frame connectors.

Look at some high HP/Torque Novas without connectors or cages that have been well used. 1/4 milers most of their lives.
The rear edge of the passenger door will bulge out slightly from the door opening at the 1/4 panel. Anywhere from a 1/32" up to 1/4".
That's from the door being squished as the body shell twists!

 

[Schurkey]

...and the door-opening/roof cracks on every 2nd Gen Camaro/Firebird ever made.

Kid's gonna remember that his whole life. Proud of you, dude.

Of course, the Safety Nazis will accuse you of child abuse, kidnapping, etc.



I have figured there's a similar engineering philosophy between chassis/body engineering, and Hi-Fi speaker cabinet engineering.

In both cases, the traditional philosophy is that the chassis/body, or the speaker cabinet cannot be made rigid enough. All torsional deflection, or panel vibration, takes away from proper driving response or proper sound quality.

But someday, we're gonna be smart enough to use that chassis deflection or panel resonance to advantage. Truth is, the OEMs already use intentional chassis deflection to soften the ride, and reduce NVH; and they have for decades--but this does not improve chassis response, or steering precision. It improves "quiet" and "isolation" including on Karts that have no suspension other than chassis flex (which may be deliberate in some cases, but mostly is just a by-product of simple engineering.) I don't know of anyone who is deliberately allowing speaker cabinet resonance to improve sound quality. I don't think we're that smart...yet.

 

[Erik the Awful]

There is a difference between "adequate stiffness" and "all the stiffness". Once you get to a certain point you get diminishing returns, but as suspension technology keeps advancing, the point of diminishing returns keeps getting higher. Our trucks handle well, comparatively, but a lot of that is the double a-arm front suspension and 4-link rear. The lack of chassis stiffness is horrible. Still, they weren't built as race cars, and they truck very well.

Also, beaming stiffness is different than torsional stiffness, and that's where Suburbans beat out pickups. When the beaming stiffness isn't enough, the Suburban cab becomes the arch over the frame that keeps it from sagging. The pickups do not have that.

 

[sewlow]

Kid's gonna remember that his whole life. Proud of you, dude.

Of course, the Safety Nazis will accuse you of child abuse, kidnapping, etc.

He's no kid anymore. Lol!
Had a few pretty crazy rides of his own over the years.
'67 Dart GTS with a built 273 Commando. '70 340 Swinger w/a stick. Couple of SBC Camaros. A Power Wagon on 38's with a 440.
Grown kids of his own.
I first met his oldest boy when the kid was about 6. (Lived in different towns.) Buddy introduces us & the first thing the kid says is, "You're the guy that owned that black car, aren't you?"
His pending grandkids (5 more months!) will probably get to know all the stories just as well as their Dad's did.
Yea. There's more than one!
Both of his wives have had somewhat of a dislike for me.
No idea why.
But, apparently, I'm a b-a-d influence!
Moi? Nooo. Not me.

 

[Canadian Rust Bucket]

The biggest reason I'm not boxing my frame is that it'll void my insurance policy. No frame modifications allowed, unfortunately

 

[sewlow]

The biggest reason I'm not boxing my frame is that it'll void my insurance policy. No frame modifications allowed, unfortunately

Whereabouts are you in Canada?
I've had the CVSE guys (Real mechanics. With Badges. ...and guns. Coast-to-coast) under my '98 several times. (They can pull over & inspect any vehicle they please. Not just the big rigs, as per usual. Modified vehicles can be a target.)
They've inspected the notch. They've seen the partial boxing. The modified rear cross member.
Not one fix-it ticket. Have actually had a few comps on the work.
The government-run insurance monopoly here, the most money-grabbing-for-any-excuse, most rule conscious, most corrupt, the issuer of the most expensive policies in the country, is tied in directly to the cops.
If CVSE nails me for an illegal mod, the insurance co. knows within seconds of the ticket being written.
I can be refused insurance until the ticket is paid.
But I've never had a prob with the cops concerning the frame mods.

You must be registered for see images attach

 

[Canadian Rust Bucket]

Whereabouts are you in Canada?

I'm in Ontario. I'm glad to hear you've had such a good time with the cops, gives me hope!
My issue is more the specific Hagerty policy I've got. I pay ~$350 a year for the '95 c1500 as a classic daily driver and my '66 Thunderbird. It's cheap as hell, but really restrictive, because both vehicles are technically classics.

 

[azmikep]

I just did a 2” drop with $40 Amazon my 1990 GMC Shortbed measured 34 1/2” to the middle of the wheel on Passenger Side. The 34 1/4” pic was driver side. These were before pics
For what it’s worth. No wrecks I’m aware of. Trucks been in my Family since new.
3rd pic is what worked out to be 1.5” shackle lowered.
I measured consistently.

 

[RichLo]

... and my '66 Thunderbird....

Nice, I just picked up a 4-door 68 T-Bird last year. Fun summer cruiser.

 

[Caman96]

My first car was a 64 Thunderbird 390 ThunderJet. Incredible interior!