Torsional Rigidity Measurement...warning pseudoscience involved

[1990C4S]

Get it certified and remove the wiper motor and linkage. Rain-X is all you need.

[JohnJL]

I run rainex only on the race cars but I find I still want a wiper esp when traffic is slow or the rain is lite. I also want the car to be lightweight all the time.

[JohnJL]

I weighed up the OEM motor, linkage, and wiper arms and got 4.08kgs.

The new unit weighs 1.08kgs and the arm and wiper 246g so 1.33 kgs altogether.

So that's 2.75 kgs or 6 lbs savings up relatively high.

The wiper motor cost $61, and I am estimating ~6 hours of bodywork involved (removing the old "dimples" and patching them in, fabricating a bracket for the new motor.

Once I have it working I will sell off the old wiper motor and mechanism, which I venture is worth something....

[JohnJL]

Assembling nice new suspension parts is the best...waiting on Pelican to deliver the headliner.

[JohnJL]

ERP springplates, Hotbit double adjustable shocks, Tarret sway bars, elephant sphericals, ERP rod end drop links and strut double-sheer braces, etc...

[proffighter]

Due its very lowest area I would not use cylinder head bolts here to reduce the risk of ground contact. Normal ones are half the height there:

[JohnJL]

Fi g why does my thread get all the spambots?

[JohnJL]

Thanks Roland. Ill change those.

[911pcars]

Originally Posted by proffighter

Due its very lowest area I would not use cylinder head bolts here to reduce the risk of ground contact. Normal ones are half the height there:

The socket head bolts should be fine as is. After installing the factory sheet metal cover, it and the attachment bolts and maybe the height adjustment screws on each end will all be closer to the ground than those bolt heads.

Sherwood

[JohnJL]

I am not putting the sheetmetal back on (unless someone can convince me it makes you go faster?) and I wont have any height adjustment bolts....am using coilovers.

[911pcars]

Originally Posted by JohnJL

I am not putting the sheetmetal back on (unless someone can convince me it makes you go faster?) and I wont have any height adjustment bolts....am using coilovers.

Your call, but anything that smooths air flow under the car is better. Also keeps road trash and splatter away from the steering rack/fuel pump. If your front ride height is so low, threatening those bolt heads, your front bumper/spoiler should provide sufficient sacrificial rub material/notification.

Sherwood

[safe]

That cover is also a structural member in sheer.

[proffighter]

Originally Posted by safe

That cover is also a structural member in sheer.

If you look at the mounting points (and the sheet thickness) I don't guess so

[safe]

Originally Posted by proffighter

If you look at the mounting points (and the sheet thickness) I don't guess so

Been discussed here, see post 113:
In this thread: Structural Reinforcement

[JohnJL]

actually i know how to inject at least one datapoint, which is more than i have been able to see in those threads...ill do the twisting measurement with that plate in place and absent...

[JohnJL]

I dont know what you guys are complaining about, installing a headliner is easy...you just have to put it on a rotisserie!

[JohnJL]

headliner

[Walt Fricke]

And I thought I used a lot of Acco fasteners when I did my headliner.

As to the front reinforcing crossmember bolt head height, I am in the thinner is better camp. Mine, which are standard hex head, are thinner hex head due to pavement abrasion. Track pavement only, I think, but pavement all the same. I had to grind off the burr so I could get a socket on them.

What seem structurally useful here are the thick metal straps which bolt to the aluminum cross member, and to the chassis to the rear of the open hump. Obviously very strong in tension, less so in compression even though they are thick due to their slenderness ration/potential for buckling. But given all it does, helping keep the cross member upright has to be important, and they do that just fine.

A guy worried about weight could easily fabricate something plenty strong but lighter out of tubing instead of the thick strap.

My instincts tell me that the steel plate gravel guard, while it would be a fine tension member, and might help resist side to side racking through tension triangulation, would do about zilch for torsional rigidity.

Pretty easy to substitute a thin aluminum plate here. For that matter, to run it or plating generally, all the way up to the spoiler in front to smooth out air flow. Though if you exhaust a front center oil cooler downward. you have to leave at least that opening. Another reason an upward, through the hood, exit for this air is beneficial.

[JohnJL]

Hi guys.

More headliner progress, and pressed out the wheel studs in anticipation of the new longer ones on the way from MSI.

The clips came in a pack of 144....





THis is what worked for me ...

A 20mm deep socket fits nicely around the stud's head. (go ahead Ronnie...)



The socket supports the hub while allowing the stud to get pressed down.



If the press gauge read more than 750 kgs before moving, I applied about 30 seconds of MAPP torch to the hub near the stud. THe stud always let go then.

[JohnJL]

Huge progress...

Headliner fully installed
Front and rear suspensions installed
New bearings all around
New long wheel studs from MSI to accomodate the spacers from Tarett 15mm front, 19mm rear
All body panels installed and fitted
Front and rear bumpers backsides finished and painted
Front cooler mounted
Windhshield wiper holed filled and converted to a single, center-mounted wiper
Rain drip rails cut and welded
Flush mounted rear window installed
Rear quarter windows flush mounted (and waterproof)


The bumpers needed a good bit of massaging to make them fit and mount solidly. I am very happy with the quality of the panels themselves from GT.























more pics shortly