Suspension ear reinforcement, Would this work? (pic) Options

[smrz914]

I played around with photoshop a little bit. I hope 914RS doesn't mink I used his picture.

Anyway, instead of having a tube go from the ear to the firewall, I thought that one could take some sheetmetal and create a shelf. I don't thin this will work for /4 but it might for converted cars. I thought a cross section might look like
_____
|_____\__________


Would this be strong enough? Just seeing if there is a nice way of doing the brace. So It would be like having another shelf. I don't know how low the engine mount goes but I think one could work around that. On the ear the attachment point would be pretty low and be able to handle movement better. On the firewall site it would attach to the back edge of the floorpan.

[Series9]

As long as the box tubing is substantial enough, I think that would work fine.

[smrz914]

In that case the question becomes, what is substantial enough?

[Porsche Doc]

Hey smrz914,

Here is the way we do it to all our hot rods and race cars.
We box the almost all of the suspsion console with 12Ga like the GT stiffing plates.
The ReaL week point is the lower section of the ear.
It takes the most load. The tubing is good to add also
Here's some pics.

[Porsche Doc]

another

[Series9]

QUOTE (smrz914 @ May 3 2005, 08:18 PM)

In that case the question becomes, what is substantial enough?

.125" wall and .75" x 1.5" box tube would be the minimum I would use in your design. That being said, I would still want to see it in person before I made a final judgement.

[John]

I did my race cars similar to Porsche Doc. I fishplated the console and then added tubing. My tubing goes through the firewall and ties into the cage.

The shelf idea is interesting, but what are you attaching it to at the front? (the floorpan?) You may need to add some strength to that if you tie in there.

To add stiffness to a structure, your anchor points must be substantial, or you are wasting your time.

If you decide to go ahead with the shelf and rectangular tubing, I would consider adding some drain holes to the shelf.

just my $0.02

[Brett W]

Don,
I didn't see you and Charles at the Mitty. What happened?

[smrz914]

Thanks guys I'll have plenty to mull over for a while. I'm just making plans for my project. Porsche Doc, did you add metal to where the trailing arm bolt goes through the ear, possibly requiring a longer bolt, or was that left the stock thickness, and metal added around where the nut would be?

[Jeroen]

here's what I'm planning to do

weld a piece of 2" tube around the nut
then tie braces to that (braces will be weld to both the 2" piece of tubing as the susp.ear itself)

All the cracks I've seen are either at the nut or just above it
I feel the braces pictured above don't reinforce that area

This should

[JWest]

QUOTE (Jeroen @ May 4 2005, 07:51 AM)

here's what I'm planning to do weld a piece of 2" tube around the nut then tie braces to that (braces will be weld to both the 2" piece of tubing as the susp.ear itself) All the cracks I've seen are either at the nut or just above it I feel the braces pictured above don't reinforce that area This should

Watch your clearances there Jeroen - that area is close to the engine.

[Jeroen]

QUOTE

Watch your clearances there Jeroen - that area is close to the engine.

I know, it's gonna be a tight fit
The 2" tubing will only be about 1/2 an inch deep

[andys]

When adding structure to the ear and extending it to a remote location, any flexing in the chassis that is realized between those to points may cause undue transfer of loading to the ear. This may cause the cracking/failure you're trying to avoid in the first place. A localized structure that spreads the loads I would think to be a better solution. If you have a full cage, then this may not be an issue.

Andy

[Porsche Doc]

QUOTE (Brett W @ May 4 2005, 12:12 AM)

Don, I didn't see you and Charles at the Mitty. What happened?

Hey Brett Man,
We did't get to go. Charles is the PCA SMR region Pres. and he had the to go to Spring Fling thing they have.
BUT we will be back next year. I was told it was a big turn out.


Hey smrz914
We did not plate a the section of the ear were it bolts. Take a good look at the pic and you will see.

Hey Jeroen
You are heading for trouble with your design. (IMG:http://www.914world.com/bbs2/html/emoticons/headbang.gif) Like James said the engine is real close there.
If it has a six in it you won't get the valve covers off with out taking the engine out.

[Brett W]

Yeah 400+ cars. The 914 crowd didn't really make a great showing. Most broke or also ran.

[brant]

QUOTE (andys @ May 4 2005, 08:45 AM)

When adding structure to the ear and extending it to a remote location, any flexing in the chassis that is realized between those to points may cause undue transfer of loading to the ear. This may cause the cracking/failure you're trying to avoid in the first place. A localized structure that spreads the loads I would think to be a better solution. If you have a full cage, then this may not be an issue. Andy

Sorry no pictures currently of my 4 cylinder car..
but Jeroen its nearly like your plan.

It works.
and does not create additional problems.
I know this because I ripped out 2 suspension consoles (NO RUST) before I did the bolt in brace.

and since that time with 8-10 years I have not ripped out a suspension console.

Yes it can be close for fitment, but that is the beauty of a bolt in brace. You simply un bolt it when you want to drop the motor.

brant

[J P Stein]

QUOTE (Porsche Doc @ May 3 2005, 08:06 PM)

Here is the way we do it to all our hot rods and race cars.

I like the looks of this . To my of thinking, the lateral forces are the greatest and it happens to coincide with the weakest axis of the ear and since the damn things seem to rust from the inside out......I'm thinkin' of removing the entire inside half of the ear & fabing a 3/16" plate to replace it.

Jeroen:
I had to grind down my turbo valve covers about .3 in in order to clear the end of the pivot rod in order to get em' off & on.
The more "stuff" in the way the worse it's gonna be.

[MecGen]

Hi
I followed a couple topics like this and got some real help. My experience has been that they break at the bolt hole across, then fold outwards to the direction of the fender. I wonder if Brants broke this way.
My research left me to understand that, if the ear is in good condition, its ok for almost anything on the street. If it is so-so but save-able, it should be re-inforced.
I just don't think the solution offered here has any real benifit for the street. I look hard at mods to preserve my car....still looking at it.
Later..
Joe

(IMG:http://www.914world.com/bbs2/html/emoticons/beerchug.gif)

[brant]

QUOTE (JoeSpark @ May 4 2005, 04:13 PM)

Hi I followed a couple topics like this and got some real help. My experience has been that they break at the bolt hole across, then fold outwards to the direction of the fender. I wonder if Brants broke this way. My research left me to understand that, if the ear is in good condition, its ok for almost anything on the street. If it is so-so but save-able, it should be re-inforced. I just don't think the solution offered here has any real benifit for the street. I look hard at mods to preserve my car....still looking at it. Later.. Joe (IMG:http://www.914world.com/bbs2/html/emoticons/beerchug.gif)

Joe,

I want to agree with you regarding street use..
not all that necessary in my book.

and I should of added that both of my failures were on a track car not a street car

and finally, yes.. both of my failures started at the bolt hole...

The first time I thought it was metal fatigue becuase the car was 20 years old (although it had NO rust even inside)... but after we put in a brand new console and it failed in less than 1 year I sought a better plan.

That car is a -4 so the bolt in bar angles towards the center of the firewall. The console side of the bar bolts 1 inch away from the bolt hole

On the new race car the bolt in bars are similar, but with very different attatchments methods and it attatches 8+ inches away from the bolt hole with the bar running very straight forward to clear those valve covers.

On my -4, I reconverted it to a street car now. (although the motor and tranny are both currently blown) I reinstalled heat-exchangers, heat duct work, and all the stock bits right around the existing bracing bar.

In a month I'll try to get a pic of it.

brant

[Andyrew]

Any more pics Jeroen?

This is an area I will be reinforcing at my next engine pull... (probably soon...)
And I want it to be able to hold the v8's tq on hoosers with rock hard suspension...

Probably get a good welder and helmet before this as well.. lol

Andrew