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Cracked firewall

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Old 08-28-2012, 05:33 PM
  #31  
tamathumper
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I happen to have both of these braces installed on my car, so what the heck, I'll comment.

I put them on in the hopes of avoiding a firewall failure in the future, because I saw posts like this coming up from time to time, and because I did not trust a lot of the "internet wisdom" about stripe colors, original equipment, and the effects of having a possibly stiffer-than-original pressure plate. "Ounce of prevention" so to speak.

I can't see how flexure of the shaft on the D1R upper strut brace would be an issue here, as the D1R firewall brace connects directly to the mounting plate over the upper strut, and there is no flexure there to speak of. Mine is, in my estimation, solid as a rock. That brace is, IIRC, also under tension, not compression?

I had no prior failure of my firewall, and I have none now, so I can't speak to efficacy. But, I can say that I am happy with both braces, and I feel they are performing the function I wanted when I bought them.
Old 08-31-2012, 05:13 AM
  #32  
FRporscheman
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Originally Posted by Cloud9...68
If you can convince yourself you don't have an actual firewall crack, you might want to consider a brace as a preventative measure. I realize there's a strong anti-D1R sentiment among many on this site, and the last thing I want to do is stir that pot, but as an impartial customer, I have to say it is a very well-engineered piece. But you do have to buy his strut brace, as the firewall brace is designed to work with his strut brace brackets.

If you don't want to go the D1R route, I'm not aware of anyone else who makes a brace like this, so if this is indeed the case, maybe some people on this site could come up with a design for one. But whatever route you take, I'd say this in enough of a weak spot on these cars that some sort of preventative measure would probably be a very good idea, as the repair if a very expensive ordeal. Best of luck, and keep us posted as to what you find.
No, it's not a well-engineered piece. Just take a look at one of those braces while someone is pushing the clutch pedal repeatedly. You can see this "brace" flex a lot. It basically doesn't stop any of the natural flexing of a solid healthy firewall, which is small but noticeable by anyone standing next to the car. Anyone can see it, if they actually test a product rather than believe the hype.

Since it doesn't stop the flex, it won't prevent firewall cracks. BTW, the word is preventive, not preventative.

This is what I use. The result is ZERO firewall flex. Note that I'm using a heavier pressure plate in my car, and the bracket holds the firewall SOLID.


I'm not the first one to come up with this. I saw this idea on Rennlist (and anyone who takes a second to do research would find it), except they were using this type of bracket:


I just took it one step further and decided to buy a 3' length of steel angle beam from home depot. I cut off a little piece and drilled the holes in it. The key is that the small bracket above is bent into 90-degrees, so the corner is rounded. This beam has a pointed outer corner and a filled-in inside corner, or fillet, which makes it immensely stronger.


It's a cheap item from home depot. I am happy to help people figure out how to put it in. PM me.

Yes, my first post here in 1 year. Don't worry, I'm leaving again.
Old 08-31-2012, 05:47 AM
  #33  
Dimma
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Bs post, sorry
Old 08-31-2012, 05:56 AM
  #34  
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Bs post, sorry
Old 08-31-2012, 06:53 AM
  #35  
FlatSix911
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I did a bit of research and also like this solution

Originally Posted by LS1Porch
I had this problem as well. Since my car is a v8 swap i actually have it a little worse than you all, since i use a 7/8" master.
As it would happen my brake master is out right now while i switch to hydroboost, so i was able to actually get a picture of my solution!
The first thing i tried was welding a wedge that oriented the master vertically. That helped a lot but i was still getting a millimeter of flex.

My ultimate solution (which i think is also a very easy solution, especially to those who don't want to weld on their firewall) was to take a strip of 1" wide metal and make a "P" shape out of it.
I then slid the loop of the P over the master cylinder and bolted the leg to the fender below it. Zero flex!




While i'm on the subject, i found that the CNC brand of master cylinders are an okay fit for these cars. I had to massage the shock tower a small amount and use a 90* line adapter, but no big deal.
Previously i had tried Wilwood and Tilton stubby master cylinders (failed very quickly). The full-size masters from both Wilwood and Tilton will not fit with any amount of pounding.
Old 08-31-2012, 06:22 PM
  #36  
tamathumper
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Originally Posted by FRporscheman
No, it's not a well-engineered piece. Just take a look at one of those braces while someone is pushing the clutch pedal repeatedly. You can see this "brace" flex a lot. It basically doesn't stop any of the natural flexing of a solid healthy firewall, which is small but noticeable by anyone standing next to the car. Anyone can see it, if they actually test a product rather than believe the hype.
This concerned me tremendously!

I installed this brace as a preventive measure, as with many other things I've done on this car - I try to replace things before they fail, such as converting my cab top to manual even though the power system was working just fine, or as with the DME Relay, Heater Control Valve and other bits, I ensure I always have a spare in the cubbies.

I went to the garage with my wife in tow and had her pump the clutch pedal repeatedly while I watched for firewall movement.

I was very relieved that there is no visible movement of my firewall. That's not to say there won't be movement of someone else's firewall, but in my case at least, I'm good to go.
Old 09-03-2012, 12:04 AM
  #37  
Lord_Galva
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Wow, what a weekend.
I spent most of Saturday with my friends fabricating a huge version of D1R's brace.
It's roughly 3x the size and 50x more ugly.
It is "N" shaped using steel for the wall and aluminum for the rest.
I have to fabricate a new "clevis" for the clutch to negate the extra distance it has to travel because of the new brace.
Once it is all done I'll post pics.
Old 09-03-2012, 12:07 AM
  #38  
Lord_Galva
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Sneak preview
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Old 09-03-2012, 12:52 AM
  #39  
JDS968
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Holy crap that's ugly. Looks like it could be very effective, all depending on what it's attached to. Are you just hooking it up to a strut tower brace, and if so, what brace are you using?
Old 09-03-2012, 02:31 AM
  #40  
Lord_Galva
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Originally Posted by JDS968
Holy crap that's ugly. Looks like it could be very effective, all depending on what it's attached to. Are you just hooking it up to a strut tower brace, and if so, what brace are you using?
You were supposed to say "that's not that bad." Lol.
I am connecting it to a KLA strut tower brace.
Old 09-03-2012, 12:10 PM
  #41  
Cloud9...68
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Are you welding the piece you fabricated to the firewall, or bolting it on?
Old 09-03-2012, 12:23 PM
  #42  
968gene
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Instead of modifying the shaft length, why not bolt your brace over the master after it is installed in the factory location?
Old 09-03-2012, 02:29 PM
  #43  
tamathumper
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I'm all for the Do-It-Yourself approach when it makes sense. With the brake master being right there, I'd be really nervous about cobbing something together in this case. Isn't there a chance of losing braking ability if your repair fails? If so, please consider your safety and the safety of others.
Old 09-04-2012, 06:55 PM
  #44  
Lord_Galva
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Originally Posted by tamathumper
I'm all for the Do-It-Yourself approach when it makes sense. With the brake master being right there, I'd be really nervous about cobbing something together in this case. Isn't there a chance of losing braking ability if your repair fails? If so, please consider your safety and the safety of others.
Nah, the brace goes around the brake booster. Hence the shape.
The brace pushes a steel plate that goes around the clutch MC mounting area.
So far the biggest downside is needing to adjust the clutch pedal.
I was planning on posting pictures today but my camera has gone awol.
Once I find it I will put them up.
Old 09-04-2012, 08:06 PM
  #45  
Max Energy
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Gentlemen,
I have two versions of firewall reinforcement plate.
A bolt on aluminum or a weld on steel version.
They reinforce both the brake and clutch.
I would be happy to send you a picture if you furnish me with your email address.
Max
maxenergy@***.net


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