My front plate was already dented by the PO so I'm not concerned about.it right now. I zaw a pozt were they removed the plate and welded in a support in the center then rewelded the plate back on. I dont think it added more than 1-2 pounds at most. I add more than that everytime I squeeze my fat butt into the seat

 

YEP..I am right there with you.
I am assuming that 'my method' is raising the rear of the car from the back...under the differential area...CORRECT???

AS it should because you are using the frame as a support point....SO I am guessing that there is a lot of frame and weight out past where you placed you jack stands. I am guessing you placed the rear jack stand on the frame IN FRONT of the rear wheel...SO...all the frame behind this point is causing your rear clip to sag.

I would NOT leave it there for 5 minutes. PROBLEMS can being to arise...

YES...DAMAGE can result form this. I will explain as best as I can. When I jack up a Corvette and have to place four jack stands with FOUR legs on them. 99% of the time I remove the wheels and place my jack stand under the wide section of the brake rotor..and the brake rotor has had the lug nuts re-installed just in case the rivets have been drilled out to keep the rotor solid. I do this to mimic way the car would be if it still had a wheel/tire on it...and thus...using the suspension to support it and NOT the frame. I will sometimes place my jack stands UNDER the lower control arms where the shock absorber is connected to support it. BUT the rear is under the rotor as like I mentioned....OR IF I am doing rear trailing arm/suspension work....and I can not use the rotor as a support point. I have huge/tall jack stands that can support the frame on the cross member that is behind the differential crossmember.

AND if I am doing front suspension work. I DO NOT 'dilly-dally' around. I get the front suspension removed and dropped out and then I will use my tall jack stands and go up in the pocket for the coil spring.

I try to keep my support points as far forward and rearward as I can...so the frame will not sag or froth clip sags and allows the cowl/plenum to begin to have 'issues' due to a car sitting up for a long time and slowly applying stress to an area that is was not designed to fight against.

The reason I am writing this again....and I might get subjected to people who feel i am full of crap...BUT..as I wrote in a thread months ago. I had to repair a 1967 Corvette convertible that a shop in town left up on a lift over the weekend..and when they lowered it and tried to close the doors...they WOULD NOT close. It was flat-bedded to me so I could pull the frame to get the frame/body correct again....because they left it up on the lift and the weight of the engine...and the rear clip with a tank of fuel was allowed to apply pressure out past the contact points of where they set the lift points and the frame and body with previous issues from 'who knows what' caused the body and frame to move and thus the doors would not close. FIRST mistake the shop made was NOT using the tall safety stands you place under the front and rear of the car when it is up on a lift where the suspension can drop. BIG MISTAKE THERE!...or at least letting it get back on the ground if the suspension was still intact.

I work on about every grade of Corvette you can imagine. Some are still stout and strong....and some of the convertibles I work on ...IF I put a jack stand in front of the rear wheel and let down the jack stand...I could not get a cigar to stick in the gap between the door and the quarter panel because it sagged so much. SO....I always err on the side of caution and always assume that there is a pre-existing problem.,..that way I am not fixing something I do not need to fix. And the SAME goes for the front clip and cowl plenum area due to the engine weight bringing down the front end. PROBLEMS can develop there in time.

DUB

 

A flat rubber pad would scare the heck out of me due to possible slippage of the car. I could not trust the rubber to grip it when lifting it..,,,and PLEASE understand that for 30+ years I have ONLY used floor jacks with teeth on the saddle...and I jack them in a manner that the car can not clip off the teeth once that have caught on something. "Things' can happen in a blink of an eye..and I KNOW this from personal/professional experience.

Obviously...do as you wish.

I do get contracted out from time to time to either weld in a plate on the front cradle due to it being dented/damaged. And I also have some customers who want me to make a removable jacking plate that is form fitted to the underside of the cradle where the floor jack is going so it can be attached and removed.

DUB

 

Hey Dub. Im going to start a new thread not to hijack this one, if you could chime in on it that would br great, thanks
https://www.corvetteforum.com/forums...post1592095173

Scott

 

LOL omg enough about the jacks! I do not have a lift or have ever used one but have jacked a lot of freaking cars and I know what a jack slip/movement sounds like.

I swear my front sags a bit when I jack it from the sides and then goes back to normal as I set it on the stands under the shocks. My car is below 3000 FYI

Still haven't finish up with the front and can't jack the rear until, so it doesn't spill fuel. I'm being cheap and didn't buy a couple 6an caps yet.

 

I am GLAD this works for you. And with you placing your jack stands under the control arms..the front clip will go back as it should...you are SPOT ON!.....BUT...a lot of people will set the jack stands at the hinge post /door gap area....and the front clip will sag and can get worse.

SO...with your car... and you KNOWING what to look for...then DO NOT be surprised that ONE DAY when you are jacking it up like how you have been...that you notice the gap at the door and front clip is getting A LOT wider. IT can happen....especially if you are jacking it up on the frame at the door gap/hinge post area.

Keep in mind... I jack up Corvettes that are NOT mine....so..the way I jack them and support them has given me great results. When I am jacking up a car from the front or rear. I do not have to worry about gaps widening...because that can not widen.

Sorry that your thread took a route that seems to no longer benefit you. But the process of raising and correctly supporting a Corvette is IMPORTANT....and I tried to treat it as such.

As far as I am concerned in this thread...I am DONE..and people can do what they want. It seems pointless to try to pass along years of experience of working on hundreds of Corvettes.

DUB

 

I was talking bout the jack pad slip not the jack point DUB