Body flex causing top fitment and window issues, On lift I get 25 1/8" and on the ground it changes to 25"? Options

[Steve]

What is the consensus on flex regarding the roll bar to windshield flange measurement?
Item "F" on the body dimensions page.
http://www.914world.com/specs/bodydims.php

My car was fine until I had a shop weld in the Engman long kit. The car is much stiffer, but the windows and top no longer fits right when the car is on the ground.
On the lift I get 25 1/8".
Off the lift I get exactly 25"

How much should the car flex when on my scissor lift versus on the ground?
The scissor lift is using the four jack pods to raise the car.

Should the car be like 25 1/4" on the lift and 25 1/8" on the ground?
Is 1/8" flex normal? What is everyone else seeing?

I will post some pictures tonight.

[Tom_T]

Steve, any stiffening kit should make it flex less, not more than before - if it was installed correctly IMHO.

The flex you describe is mostly likely happening in the longs & bottom body/floor panel - in order to now open & close gaps when lifted & on the ground - & unless it did that before the kit, then the shop may have installed the longs kit with the body stressed in one direction/position or another, where the car on the ground now has mis-fits.

I'll let some other body types weigh in, but you might want to PM Alien Rick in WI about this problem.

Also may want to s post which shop did the install, in case there are others who had problems with their work who can weigh in.

You might also take it by Aase Bros. in Fullerton or Bill Brewster in Dan Point to have them take a look at the situation.

Good Luck! (IMG:style_emoticons/default/beerchug.gif)
Tom
///////

[Luke M]

I've installed the engman/maddog kits in the past and about to do another on my brothers car. I can tell you this, if you are not careful you will twist the car from welding in the kit. You need to jump around and spot weld in areas. I keep door braces on front to rear, and some sort of brace from side to side. I usually weld in a piece of pipe from side to side. Make sure the measurements are within spec prior to start welding and keep checking them as you go. If your door is on then shut it and check for any issues as you weld. Did you happen to ask the shop on how they did the job ? Once the kit is welded in you shouldn't get much movement if any at all.
You may have other chassis issues creeping up on you?
When you get some time post some pics of the problem.

[xperu]

WOW! I just posted a new thread asking for just this drawing not 5 minutes ago. Thanks! Mike/xperu

[Steve]

Door gaps on scissor lift
Passenger side



Drivers side on scissor lift

[Steve]

Door Gaps Passenger side on Ground



Door Gaps Drivers side on Ground

[rick 918-S]

The Engman kit does nothing for sag. It will assist slightly with torsional twist introduced more from the hard corner loading in the front suspension vs the opposing forces from the mid-engine weight.

Your issue is at the base of the "C" pillar at or just rearward of the jack post. Remove the rocker covers and fix the rust or fatigue in the chassis. Engman does nothing for that.

You need to go deeper now to see if the chassis was twisted during the welding process.

You need to think about this in 3D. F and X are good. Y and G will tell a different story. G will tell you side for side if someone over time bent the windshield frame up or down to get a fit to the window frames or targa top. Y will be a more accurate measurement than X because the windshield frame is easy to bend out of place.

In most cases we are checking chassis' for sag from rust damage not collisions. So if you get a good G AND the door fits the front fender line AND the windshield frame fits the vent window,

(set the frame to spec, fit the door to the fender, adjust the vent window frame to the windshield frame)

Then you will be able to have confidence in your F and X measurements.

At that point you can address the sag at the jack post, install door opening braces and fix the soft chassis causing flex.

Oh, BTW: if your fixing crash damage the picture changes entirely.

[Steve]

The Engman kit does nothing for sag. It will assist slightly with torsional twist introduced more from the hard corner loading in the front suspension vs the opposing forces from the mid-engine weight.

Your issue is at the base of the "C" pillar at or just rearward of the jack post. Remove the rocker covers and fix the rust or fatigue in the chassis. Engman does nothing for that.

You need to go deeper now to see if the chassis was twisted during the welding process.

You need to think about this in 3D. F and X are good. Y and G will tell a different story. G will tell you side for side if someone over time bent the windshield frame up or down to get a fit to the window frames or targa top. Y will be a more accurate measurement than X because the windshield frame is easy to bend out of place.

In most cases we are checking chassis' for sag from rust damage not collisions. So if you get a good G AND the door fits the front fender line AND the windshield frame fits the vent window,

(set the frame to spec, fit the door to the fender, adjust the vent window frame to the windshield frame)

Then you will be able to have confidence in your F and X measurements.

At that point you can address the sag at the jack post, install door opening braces and fix the soft chassis causing flex.

Oh, BTW: if your fixing crash damage the picture changes entirely.

(IMG:style_emoticons/default/pray.gif)
Thanks Rick for the help!! Question.. Should there be any sag at all or should it always be 25 1/8" on or off the ground? Same thing with the other measurements?
There is no visible rust under the rocker panels. The car had a GT kit welded on 20 years ago and this problem came up after the Engman kit was welded in.
I will check the other measurements.

thanks again for the help!!!

Steve

[Luke M]

Looking at the top of the door gap pics it seams to me that on the ground it gets tighter. With that said I agree with Rick you need to start looking at your jack points for rust. You really can't tell just by looks but need to start poking around. If you find some soft/rust areas that needs to be addressed. Like anything fix one thing and something else will pop up.

On my 6 I have the same issue with the door gaps and jack points.
The pass side looked ok in some spots and in others it had some small holes. The more I dug the more rust damage I found. At the end I had to replace the hole area with new metal from RD parts # PP351 & PP331.

[rick 918-S]

Without seeing the car it is hard to tell what is going on with it. But The last car I fixed was solid on or off the jacks. If you drive the car hard you may have some fatigue? You'll have to look further. are you able to change the measurement this way?

Place the car on jack stands level as you can. (not the biggest deal just so it doesn't rock on the stands. hold the tape in place have someone lift the rear bumper then try it on the front. Then try it corner to corner front and rear with a cross measurement. I want to know if it is the front or rear changing the measurement and if one corner is weaker than another. I'll be out today but Lets see that that develops.

[76-914]

Reading posts like this I realize how "Ass Hole" lucky I am that "this grasshopper" did have something similar happen when I welded mine in. (IMG:style_emoticons/default/pray.gif)

[Steve]

Without seeing the car it is hard to tell what is going on with it. But The last car I fixed was solid on or off the jacks. If you drive the car hard you may have some fatigue? You'll have to look further. are you able to change the measurement this way?

Place the car on jack stands level as you can. (not the biggest deal just so it doesn't rock on the stands. hold the tape in place have someone lift the rear bumper then try it on the front. Then try it corner to corner front and rear with a cross measurement. I want to know if it is the front or rear changing the measurement and if one corner is weaker than another. I'll be out today but Lets see that that develops.

Thanks Rick!! Great advice!! I will know more after taking more measurements. I will put the car back on the scissor lift and raise the rear with a floor jack and see if it changes and then try the front.
I will try all four corners. Sad part is I have all the carpet and interior back in. This might be something I just tolerate until the winter break.

[Steve]

Looking at the top of the door gap pics it seams to me that on the ground it gets tighter. With that said I agree with Rick you need to start looking at your jack points for rust. You really can't tell just by looks but need to start poking around. If you find some soft/rust areas that needs to be addressed. Like anything fix one thing and something else will pop up.

On my 6 I have the same issue with the door gaps and jack points.
The pass side looked ok in some spots and in others it had some small holes. The more I dug the more rust damage I found. At the end I had to replace the hole area with new metal from RD parts # PP351 & PP331.

Thanks Luke, I will keep those parts in mind if that turns out to be the problem.

[PanelBilly]

Reading posts like this I realize how "Ass Hole" lucky I am that "this grasshopper" did have something similar happen when I welded mine in. (IMG:style_emoticons/default/pray.gif)

No shit. Me too.

[Chris H.]

I'm afraid to do mine now. There's a dude coming to Grand Rapids I heard...probably done a set before.

[Steve]

There's only two things that come from California.... Lol (IMG:style_emoticons/default/smile.gif)
Or was it Texas?