Front trunk reinforcement?, Where would you put tubing? Options

[plymouth37]

I am thinking about adding reinforcing tubing to my front trunk/shock tower area and would like to see what you have done to your cars.
Where do the tubes need to be located?
I would like to keep the stock gas tank but if I have to notch it here or there it isn't the end of the world.
Also the radiator shouldn't really be a huge concern, I can mount it anywhere.

I am thinking something like this but in the front, not full tube chassis but more tube, less sheet metal.


Here is how it looks now.


Thanks for the help!

[strawman]

As you know, a full rollcage with ties to all suspension points would provide the most stiffness/protection. But since my car will be a fun street / occasional track toy, am not considering a full 'cage. In short, I don't plan to add too much tubing in the front trunk of my Suby-engined project; I merely plan to tie in the front A-arm mounts transversely. Kinda like the 914GT projects. That will also provide a strong lower mount for the radiator in my project. I'll also seam weld the front towers like I did in ass half of the car.

The factory front wall probably provides some degree of stiffening between the strut towers, but I've never heard that it is particularly weak. Whatever you do, I'll be sure to watch -- you've got a killer project!

Geoff

[SirAndy]

I would do at least a cross brace for the front a-arm mounts.

Ideally, you'd want to tie those together with the upper shock towers as well ...
(IMG:style_emoticons/default/bye1.gif) Andy


Front A-Arm brace:

(IMG:http://www.914world.com/bbs2/uploads/post-179-1177644929.jpg)

[elmonte]

here's what Jeff Hail did. Tying all points together

[jt914-6]

Here's what my car looked like in the early stages. Braces came down from bulkhead tying into a bar across the A-arm mounts. A mount for the fuel cell was incorporated into it too.

[plymouth37]

Thanks for the advice guys.
I am not totally familiar with the 914's torsional weaknesses in this area, Would a setup like this be a waste of tubing or do you think it would help significantly?

I would rather have you wise old codgers yell at me for coming up with a stupid design now rather than after I have welded it in (IMG:style_emoticons/default/wink.gif)

[SirAndy]

Thanks for the advice guys.
I am not totally familiar with the 914's torsional weaknesses in this area, Would a setup like this be a waste of tubing or do you think it would help significantly?

Triangle good! (IMG:style_emoticons/default/biggrin.gif)

The front is usually a compromise as most people like to retain that area for something. Fuel cell, oil cooler, oil tank etc.

A X brace would probably be the strongest ...
(IMG:style_emoticons/default/popcorn[1].gif) Andy

[john rogers]

If you add the "X" tubes s you have shown I would make them removable otherwise the front area becomes nearly useless. As you have noted, the stock tank would be required and if you want to add a fuel cell then you have to go with one of the terribly expensive lined stock tanks or put a cell in front of the bulkhead. If you are going with a cell then I'd suggest getting it first even if plans are not to be needing it for several years as redoing the tubes you had put in would be a pain and look terrible. If a front mounted oil cooler is to ever be considered then I would do at least the duct work for it now and since coolers haven't changed much in dimensions since I have been racing, pick one and make the ducting to fit, again so the tubes will not have to be mod'd later on.

[plymouth37]

Triangle good! (IMG:style_emoticons/default/biggrin.gif)

Matches the back half too, gotta stay consistent!

If you add the "X" tubes s you have shown I would make them removable otherwise the front area becomes nearly useless.

Whole damn car is already useless, why stop now? (IMG:style_emoticons/default/biggrin.gif)
As long as the radiator fits I am happy. (IMG:style_emoticons/default/sawzall-smiley.gif)