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Posted by: siverson Oct 15 2011, 09:29 AM

I'm trying to figure out what's "right"... How much do your door gaps change when you jack up the car in the middle? Assuming an otherwise normal, non-rusty car.

Mine get *a little* tighter on the bottom and widen at the top - is that normal?

- None?
- Not measureable?
- 1mm?
- 2mm?
- More? A lot?

-Steve

Posted by: matthepcat Oct 15 2011, 09:48 AM

Mine is not measurable but I have a chassis kit, welded cockpit seams and firewall to rear strut tower bracing.

Posted by: Andyrew Oct 15 2011, 10:25 AM

Same, none, but I have the long stiffening kit and a solid car.

Posted by: tradisrad Oct 15 2011, 11:05 AM

no visible change, no chassis mods.

Posted by: Drums66 Oct 15 2011, 11:11 AM

.....I like to admit this, solid car with no negative change!
someone else get's the benefit

Posted by: siverson Oct 15 2011, 11:48 AM

I wonder if the 3.6 and 915 (both heavy) are part of my problem...

Posted by: sfrenck Oct 15 2011, 11:51 AM

Too much... two Brad Mayeur stiffeners in my near future.

Posted by: Drums66 Oct 15 2011, 11:58 AM

.....When going against initial engineering...I would think there would have to
be compensation in certain areas??

Posted by: sean_v8_914 Oct 15 2011, 12:42 PM

I think you must define the jacking point
are you talking about at the rear doughnut? your car is normal.
those of you that say no change are:
a. full of it
b. in denial
c. unobservant
d. all of the above

Posted by: Tom_T Oct 15 2011, 12:42 PM

The 915 isn't much heavier than a 901, and the 914 was designed to take up to the 2.7 -6 at least - had they not stopped production of the 914-6 in 72, since it was slated to get the next-last generation 911 motor as the 911 upgraded over time.

So the slightly heavier 3.6 shouldn't change the flex at the longs significantly I wouldn't think, unless there's something else going on.

Normal good longs/unibody should give about nil. You need to check for corrision issues IMHO.

Posted by: computers4kids Oct 15 2011, 01:01 PM

no change, v8
No extra stiffening

Posted by: stugray Oct 15 2011, 01:14 PM

"those of you that say no change are:"
....
or E - have a rollcage.

not only did I see no change, but the car balances on three jackstands.
The fourth jackstand is loose.

That is how stiff these cars should be.

Stu

Posted by: siverson Oct 15 2011, 05:16 PM

Thanks. Interesting conflicting opinions here...

> are you talking about at the rear doughnut?

Yes.

-Steve

Posted by: Vacca Rabite Oct 15 2011, 09:28 PM

If there is enough deflection that you can notice it, there is a problem.

Maybe not if you have a v8 for an engine, or a big 6. But for a subi or a T4 there should not be much if any deflection.

Zach

Posted by: kg6dxn Oct 15 2011, 10:30 PM

This is normal right???






This car is cut up to be reborn as a 914 trailer...

Posted by: John Oct 16 2011, 01:09 AM

Mine does not move any longer. I made my own LONG stiffeners before I ever heard of anyone else offering these for sale. Must have been 20+ years ago....

The track car does not move, but it is stiffened and a roll cage.

The future track car does not move, but it is a stripped tub.

Posted by: Andyrew Oct 16 2011, 09:42 AM

Read stiffening kits?

I remember seeing some unmeasurable amount of flex when I jacked the car up years ago. But with my v8 in the back and the stiffening kit, the chassis is rock solid.

Posted by: sean_v8_914 Oct 16 2011, 10:47 AM

throwing modified cars into the study group dilutes the real answer i think. the question was about a STOCK chassis, right?

every bone stock 914 will flex when lifted at the rear doughnut. this is not an opinion. this is an observation from a guy that deals with these cars almost every day. some flex more, some less. some flex due to rust. some due to chassis fatigue. some have spot welds that give up along the seams. some were driven by grandma while some wore slicks for 10 years.....
all this affects how loose the chassis has become

if you think that your stock 914 chassis does not flex then you are an optimistic person and I like upbeat positive people

Posted by: somd914 Oct 16 2011, 11:48 AM

Can't say that I have ever measured it, don't think an eyeball and a casual glance would notice a 1-2 mm change. Do know there is no change that jumps out at me and both doors open/close the same when on a single stand, multiple stands, or on the ground. But does this mean the chasis isn't flexing? I wouldn't draw that conclusion. And yes, I typically use the donuts, oh, stock 2.0 setup.

Posted by: stewteral Oct 16 2011, 11:55 AM

sean_v8_914,

LOL!! You sure hit the nail on the head.

For my car there is 0 change thanks to my full rollcage that ties in all the suspension towers.

I now know why my 1st 914 (30 years ago) always had a squeaky roof: the chassis was flexing over bumps in the road!

Best,
Terry

Posted by: Drums66 Oct 16 2011, 03:08 PM

....All we proved is it's debatable
(any more theory's)

Posted by: JmuRiz Oct 16 2011, 06:25 PM

Which cockpit seams are welded? Just curious for when I install an inner long kit.