Extra firewall brace.
#53
Interesting stuff. Stumbled across the thread being bored lol. Just for thought, my 92 RS with the LO3 has the brace from the shock tower to fender, but not from firewall to fender. There arent even holes drilled to indicate a past presence or even any intention of it being installed from the factory.
Hardtop LO3 RS, F41(or w/e) handling package, factory 245/50's
Hardtop LO3 RS, F41(or w/e) handling package, factory 245/50's
Last edited by Phatfiddler; 08-08-2006 at 03:35 PM.
#54
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It's amazing that GM could fit braces there, especially with the pipes from the AC, and the conduit for the engine harness. That's a very tightly packed area. Are these frame rail/strut tower braces the same length as the fender brace? Who has part numbers?
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Re: Extra firewall brace.
Hi Iroctopless,
I've been looking for info on the hardware used to attach the pencil brace (fender brace) that's in your ASC manual. Would you be able to post a bigger scan of that page or let me know what the GM part numbers are in the upper right? I'd really appreciate it.
Thanks!
John
I've been looking for info on the hardware used to attach the pencil brace (fender brace) that's in your ASC manual. Would you be able to post a bigger scan of that page or let me know what the GM part numbers are in the upper right? I'd really appreciate it.
Thanks!
John
#56
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Re: Extra firewall brace.
I'm going to go out on a limb and guess that a reply to a 10 year old thread, specifically to a member that hasn't even logged in since 2013, probably isn't going to be seen by that person.
The GM parts illustrations don't show the hardware for that brace, from what I can see. Just from squinting at the ASC diagram, it says something to the effect of Screw w/washer and nut with washer, and the size which is most likely M6x1.0x?.
I've seen all kinds of hardware used for that bracket. The end at the firewall is usually tapped, and often stripped. While the bolt and nut may be correct, a stamped steel U-nut slipped over the end of the brace works as well or better. Any M6 body bolt with a captive washer and 10mm hex head will likely look correct.
The GM parts illustrations don't show the hardware for that brace, from what I can see. Just from squinting at the ASC diagram, it says something to the effect of Screw w/washer and nut with washer, and the size which is most likely M6x1.0x?.
I've seen all kinds of hardware used for that bracket. The end at the firewall is usually tapped, and often stripped. While the bolt and nut may be correct, a stamped steel U-nut slipped over the end of the brace works as well or better. Any M6 body bolt with a captive washer and 10mm hex head will likely look correct.
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Re: Extra firewall brace.
Thanks scooter - I think u-nuts is correct. Would you happen to have or be able to post/send a picture? I'm trying to figure out exactly what GM used and do the same on my car.
I really appreciate your response.
I really appreciate your response.
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Re: Extra firewall brace.
You'll have to remind me in about a week. I leave for a business trip in about 30 minutes and my hood cable needs to be replaced so sometimes it is a huge pain to open the hood, so I can't do it now. PM me next Saturday in the morning and I will go take a picture
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Re: Extra firewall brace.
Is this thing on?
While I wouldn't put it past the factory to make running changes and substitutions to hardware (because they do it all the time), U-nuts on both ends isn't 100% accurate for every place they used that brace. As I mentioned earlier, the cowl end of the brace is threaded on plenty of them, and didn't require a nut, just as the ASC diagram shows. That said, the easiest way to fix a stripped thread is a U-nut. If you go out on Ebay, you can search for almost any part and find one or more with the mounting hardware included. If you look today, you'll find at least one example of the brace in question with U-nuts on both ends. If I walk out to my garage, I can find at least two with the cowl end threaded.
Just because one car has U-nuts on both ends doesn't mean they all did. If a person is EXTREMELY concerned about being accurate, they'd want to copy a car of the same year, same options, from the same factory, produced at the same approximate time period. However, since the assembly line was subject to human error, you can get away with almost anything that you suspect is plausible and no one is going to question it.
While I wouldn't put it past the factory to make running changes and substitutions to hardware (because they do it all the time), U-nuts on both ends isn't 100% accurate for every place they used that brace. As I mentioned earlier, the cowl end of the brace is threaded on plenty of them, and didn't require a nut, just as the ASC diagram shows. That said, the easiest way to fix a stripped thread is a U-nut. If you go out on Ebay, you can search for almost any part and find one or more with the mounting hardware included. If you look today, you'll find at least one example of the brace in question with U-nuts on both ends. If I walk out to my garage, I can find at least two with the cowl end threaded.
Just because one car has U-nuts on both ends doesn't mean they all did. If a person is EXTREMELY concerned about being accurate, they'd want to copy a car of the same year, same options, from the same factory, produced at the same approximate time period. However, since the assembly line was subject to human error, you can get away with almost anything that you suspect is plausible and no one is going to question it.
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Re: Extra firewall brace.
My guess is that it may be a location build thing. Both my cars are hard tops and one is a 91, the other a 92, so I doubt it is a year difference.
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Re: Extra firewall brace.
OK, my 91 GTA has a brace and there is a clip on one end and not the other. My 92 Firebird, base model, has no brace
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Re: Extra firewall brace.
My guess is that you will find some cars have it and some don't because perhaps previous owners removed them for whatever reasons (rebuilding/swapping engine and forgot or didn't want to put it back on, attempt at removing as much weight as possible, etc. etc.). What are the odds that a body shop didn't put that bar back on in the event they had to remove/replace the passenger side fender for repair/replacement?
I'd say try and find as many pictures of engine bays from when these cars were brand new and see if the bars are visible in those pix.
Everyone knows over time/years, owners and mechanics will sometimes leave stuff off the cars when they have been working on them. I can't count how many times mechanics will remove stuff from any of my cars I've owned over the years and forget to put little things back on like clips, covers, brackets and whatnot. Seems the most popular thing that turns up missing on these cars that I've seen in pix from looking for a third gen to buy is that little cover at the back of the plenum that covers the distributor cap. About 20% of the time I see those missing from cars for sale on ebay.
I'd say try and find as many pictures of engine bays from when these cars were brand new and see if the bars are visible in those pix.
Everyone knows over time/years, owners and mechanics will sometimes leave stuff off the cars when they have been working on them. I can't count how many times mechanics will remove stuff from any of my cars I've owned over the years and forget to put little things back on like clips, covers, brackets and whatnot. Seems the most popular thing that turns up missing on these cars that I've seen in pix from looking for a third gen to buy is that little cover at the back of the plenum that covers the distributor cap. About 20% of the time I see those missing from cars for sale on ebay.
Last edited by JonBlake; 05-20-2016 at 03:07 PM.
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Re: Extra firewall brace.
Very cool vid. Just makes me wish I could step into a time machine and go get that car. Good information too. So the transmission was in an aluminum casing. How did those tranny's hold up over the test of time?
About the brace, well he does mention the brace but only what it's purpose was. Most of use sort of had an idea, or at least I sort of had the idea it was meant for some type of chassis support/stiffening. What's still left unanswered is which third gens got it, which third gens didn't, and why/what reason.
My best guess is like what I mentioned earlier, they were removed after they were sold for whatever reason and/or perhaps it was a part the assembly plant may have run out of so they just built them without it instead of holding up production. As I recall in another thread, there was a lot of pressure and drive to get as many third gens off the assembly line and delivered to customers in a timely manner because delays at the plant were causing customers to get their new car from competitors.
About the brace, well he does mention the brace but only what it's purpose was. Most of use sort of had an idea, or at least I sort of had the idea it was meant for some type of chassis support/stiffening. What's still left unanswered is which third gens got it, which third gens didn't, and why/what reason.
My best guess is like what I mentioned earlier, they were removed after they were sold for whatever reason and/or perhaps it was a part the assembly plant may have run out of so they just built them without it instead of holding up production. As I recall in another thread, there was a lot of pressure and drive to get as many third gens off the assembly line and delivered to customers in a timely manner because delays at the plant were causing customers to get their new car from competitors.
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#69
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Re: Extra firewall brace.
If you look, there's a bead of seam sealer that runs along the firewall lip. In many cases the seam sealer covers the mounting hole. I've seen enough cars with the hole blocked to know that plenty of thirdgens never had a bolt through the hole for the brace. There are enough original, untouched cars out there to see that it was simply not installed all the time. Whatever the reason you can have two nearly identical cars that came off the same assembly line, and one may have it while the other doesn't.
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Re: Extra firewall brace.
[QUOTE=Klortho;2971042]
Circled, both my V6 Firebird and GTA has it, but doesn't have the crossbrace.
I never realized my 1987 Camaro LT had this brace from the factory. I guess I should pay attention more to the details especially since I've had it since 1993. LOL
Originally Posted by twobirds
Circled, both my V6 Firebird and GTA has it, but doesn't have the crossbrace.
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Re: Extra firewall brace.
[QUOTE=MY87LT;6041454] Yeah, that brace looks like it's more for stiffening up the chassis. The "pencil" brace everyones talking about, I'm not sure exactly what it's for. Because it connects from the passenger side hood hinge to the lip of the firewall. I'm starting to wonder if it was something that they designed after running a series of crash tests for safety in the event of a crash or something. Because if you take a look at that "pencil" brace, what could that provide/contribute to the strengthening of the suspension and/or chassis? It's just running from the bottom of the hood hinge to the firewall.
Another possibility is maybe it keeps the fender in place in the event the body flexes.
Another possibility is maybe it keeps the fender in place in the event the body flexes.
Last edited by JonBlake; 05-23-2016 at 01:07 PM.
#72
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Re: Extra firewall brace.
Never gave it much thought, but I wonder if that brace has something to do with the antenna being mounted to the fender?
#73
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Re: Extra firewall brace.
Seems to be more of a Camaro thing honestly, I do not think i have ever owned a car with it... and I have had about 10 3rd gens.
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Re: Extra firewall brace.
I don't think its only a Camaro thing. I've seen many Firebirds that have had it and I just bought a '92 T/A that has it.
#75
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Re: Extra firewall brace.
I said "more" of a Camaro thing, I know that several Firebirds had them, just none of the cars I have owned. It might have been a weight saving issue to not include them on some cars.
#76
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Re: Extra firewall brace.
Whatever the case may be, I'm sure it doesn't have anything to do with chassis stiffening. The biggest reason I say this is because it connects to the hood hinge. Hood hinge really doesn't have much to do with the stiffness of the chassis.
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Re: Extra firewall brace.
Better pic of the frame rail to strut brace. (this car has all 3) I have seen this brace on the driverside strut tower on 1 car I parted out. (92 GTA 305auto ttop leather cd player car)
Last edited by TTOP350; 05-24-2016 at 06:25 PM.
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Re: Extra firewall brace.
We all might be talking about a different "pencil" bracket. The one shown in the Clark Kent video is the one that is also shown in a pic attachment by a previous poster. It's the one that runs from the firewall to the passenger side hood hinge.
The one shown in the pic below, that's more of a structural hardening/stiffening I'd say. Even could be something added to help keep the weld that holds the top part of that metal from cracking/separating from the rest of the strut tower.
The one shown in the pic below, that's more of a structural hardening/stiffening I'd say. Even could be something added to help keep the weld that holds the top part of that metal from cracking/separating from the rest of the strut tower.
#80
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Re: Extra firewall brace.
I posted the following some time ago, but it might still prove interesting:
https://www.thirdgen.org/forums/susp...e-confuse.html
JamesC
https://www.thirdgen.org/forums/susp...e-confuse.html
JamesC
#83
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Re: Extra firewall brace.
I posted the following some time ago, but it might still prove interesting:
https://www.thirdgen.org/forums/susp...e-confuse.html
JamesC
https://www.thirdgen.org/forums/susp...e-confuse.html
JamesC
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Re: Extra firewall brace.
I think the right side bracing is added because there is less sheet metal extending from the strut tower to the firewall, due to heater box. If you look at driver's side, the strut tower to firewall sheetmetal is different, because did not need to leave space for the heater box and fan.
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