[Cloud9...68]

With the help of my very knowledgeable and experienced neighbor, I just pulled the engine out of my car. I did this largely to make it easier to repair the "8-inch gash" in my firewall, which the shop which did the PPI on my car (when I was trying to sell it - changed my mind) claimed was so bad it wouldn't be a good idea to continue driving the car. And they quoted $2000 for the repair.



As you can see in the pictures below, other than it being understandably a little dirty after 19 years, the firewall looks perfect! With the clutch and the front suspension totally out of the car, I unfortunately can't test to see how much the firewall might be moving during the application of the clutch or brake pedal, but the guy who did the PPI was very descriptive about there being an 8" gash in the firewall near the brake master cylinder. I crawled into the engine compartment, to get a closer look, and there's no trace of any damage to the firewall.



I'm going to give the shop the benefit of the doubt and assume that when one of their guys whomped down on the brake pedal with another one watching the firewall, they saw some movement, which is probably typical on these cars, and assumed the firewall was cracked, seeing as this is a pretty common condition.



So, based on what I see, I think all I need to do is buy the standard D1R firewall brace, and have the pleasure of installing it with the engine out of the car. Although I guess this means I also need to also purchase the D1R strut brace, which is a bummer, since I already have a Cargraphic brace, but Flash's is a whole lot prettier. Plus it's a whole lot cheaper than paying someone to weld a gash, and then fabricate some sort of plate.



Any other thoughts as to how I should test the integrity of my firewall with the car in its current condition? Thanks.

Partial Post: Please Login or Register to read the full post.

[flash]

the gash is usually right below the clutch master cylinder, which i cannot see in the shots

Partial Post: Please Login or Register to read the full post.

[Monstrous4Banger]

Looks pretty clean in the pics. Youd think you would be able to see a crack even if there wasnt stress being applied.

Partial Post: Please Login or Register to read the full post.

[Monstrous4Banger]

[quote name='flash' timestamp='1298874314' post='105724']

the gash is usually right below the clutch master cylinder, which i cannot see in the shots

[/quote]



The clutch, and the brake share the same master cylinder dont they? The slave cylinder, or the master? Are you talking about the one off of the bellhousing? The only clutch cylinder bolts to the bellhousing AFAIk. The master cylinder is on the firewall.

Partial Post: Please Login or Register to read the full post.

[jaap]

The clutch and brake share the same (although separated internally) fluid reservoir but the clutch has its own master cylinder. The clutch cylinder is located (when standing in front of the car) slightly to the right and lower than the brake cylinder. In the top picture you can see the D1R braided clutch line appearing from behind the brake booster.



Jaap

Partial Post: Please Login or Register to read the full post.

[968TDG]

I have a crack in my firewall...well, it is really just a splitting at the top where the two pieces of sheet metal meet above the master cylinder. It was caused by the force of the clutch pedal system. I ended up having to fabricate a turnbuckle system to go where Flash's firewall brace goes. This allowed me to preload against the firewall in the opposite direction, which closed the gap and supported the force of the clutch pedal.

Partial Post: Please Login or Register to read the full post.

[Cloud9...68]

Flash and 968TDG,



Thanks; I'll take a closer look in the area you describe above and below the clutch master cylinder when I get home tonight. If I missed anything, this is the most likely area, because it's still pretty buried behind hoses and wires and such. I don't know if I should hope I find something, which would make the effort of pulling the engine more worthwhile, or hope it's OK, which would mean one less thing to repair.

Partial Post: Please Login or Register to read the full post.

[bombfactory]

Hmm something definitely is fishy. I would think if you had 'an 8-inch gash' in your firewall you'd have probably felt it, and heard it, even if you couldn't actually see it. Were you getting any discernible firewall flex at all?



-Austin

Partial Post: Please Login or Register to read the full post.

[Cloud9...68]

I wasn't getting any discernable firewall flex, but if the tear, if it exists, grew gradually, I might not have noticed it. I really need to get a better look at the area around the clutch master cylinder. I think I may have read too much into the mechanic's rather graphic description of the "8-inch gash" in my firewall, to the point that I was expecting to see blood dripping from it or something, when in fact its physical appearance many be more subtle, and may be hard to see without somebody pushing on the pedal.

Partial Post: Please Login or Register to read the full post.

[astroede]

Great project! I'll be watching with interest. Thanks for posting great photos as you dig in. You are certainly courageous. Bravo.

Partial Post: Please Login or Register to read the full post.

[Cloud9...68]

Courageous, or maybe just not very bright <img src="/forum/images/smilies/968/blink.gif" class="smilie" alt="" /> . I sure hope I did the right thing by going to all the work to pull the engine. If it really does have a gash in the firewall, it will definitely be easier to fix with the engine out. I still can't see it; the brake master cylinder really blocks the view of the area near the clutch master cylinder. Of course, if I replace the rods, which I plan to do unless someone can talk me out of it (I'm all ears <img src="/forum/images/smilies/968/wink.gif" class="smilie" alt="" /> ), engine removal will have been necessary, because apparently you have to pull the crank to have it balanced along with the rods and pistons as a unit.

Partial Post: Please Login or Register to read the full post.

[Monstrous4Banger]

I see where the master is now. I had to look at mine. Luckily Ive never had to change it, or a brake master. The slave wasnt fun. You might have a better chance looking at it from the top. I have a 951 with the motor out right now, looking at the area, Im haviing a hard time seeing where it cracks. Looks like if it would happen any where it would be along the seam, where the wheel well meets the firewall.

Partial Post: Please Login or Register to read the full post.

[Cloud9...68]

Yeah, even with the engine out, it's hard to see much in that area. I think I'll have to remove the master to get a decent look.

Partial Post: Please Login or Register to read the full post.

[Cloud9...68]

I finally got a close look at the location of the damage to my firewall, and took some pictures. It turns out there isn't an actual crack in the firewall. I can't press the clutch pedal, since the clutch is currently out of the car (seeing as it's attached to the engine and all...), but the clutch master cylinder moves noticeably upon the application of only slight pressure from a pry bar. So I got inside the engine bay while my neighbor Gerald (the guy who helped me pull my engine) pressed on the clutch master cylinder with the pry bar, and I could clearly see the firewall moving where it intersects the inner fender well. This is immediately to the left of the clutch master cylinder.



Neither of us could see any attachment points that may have broken, so Gerald theorized that there may be some sort of attachment that's visible from inside the passenger compartment may have broken. Unfortunately, the car is parked very close to the garage wall, and is jacked up on four stands, making it very difficult to crawl into the driver's side and get my head into the pedal area to take a look. Does Gerald's theory sound right?



Based on what I've described, what's the best approach to fix this? I agree with Gerald that it doesn't look like there's anything to weld from inside the engine compartment, which is good, because it's very tight and crowded where the firewall is moving. Since there isn't an actual crack, could I get away with just installing the D1R brace that's currently available? Or should I wait until the car is in a state where I can get a look from inside the footwell, and possibly have whatever welding that may need to be done? Is is any easier the install the D1R brace with the engine out of the car? If so, could I install the brace first, and do any welding that may be needed inside the car later? Does is seem like the currently-available D1R brace will take care of the problem, or do I need to wait for the new one Flash is working on?



Here's the picture. I took it from inside the engine bay, looking up toward the clutch master cylinder. The firewall can be seen to be moving near the lower clutch master cylinder attaching nut, where the firewall intersects the fenderwell.

Partial Post: Please Login or Register to read the full post.

[flash]

the firewalls flex a bit even on perfect cars - it's not the best design - that's why they fail



the standard brace will limit that and should prevent failure - it would be a bit easier to install with the engine out, just because you can get your hands in more spots



i should have the prototype for the new brace done in about 2 weeks - i am sticking it in with the sheet metal run for the SC kits

Partial Post: Please Login or Register to read the full post.

[Cloud9...68]

Flash,



Thanks for the quick response. This is where I REALLY wish I could take a look at another 968 to see how "normal" (or not) my car is. So if you place a pry bar between the clutch master cylinder and the fender, and apply slight pressure, it's normal to see the master cylinder move a bit? And is there no attachment of the firewall to the inside of the fender where the firewall and fender meet? If not, then I would expect to see some movement, even on a new car, because the clutch master cylinder is near the very edge of the firewall.



Without giving too much away, based on what I've described and shown, am I a better candidate for the new brace, or the current one? Thanks again.

Partial Post: Please Login or Register to read the full post.

[flash]

i'll have to go and do what you describe and try to get some sort of measurement of movement - then we can compare those and see if you are "normal" or not - if you are, the existing brace should be fine - it really limits the amount of movement if everything is solid, which would prevent the damage

Partial Post: Please Login or Register to read the full post.

[bombfactory]

Not to slag the effectiveness of Flash's firewall brace, as this is just my experience, but I didn't notice any difference in the amount of firewall flex I was getting before and after installation of the brace. It's not a 100% cure for the problem, nor do I think Flash intended it to be. I do believe it is helping tho, and I sleep a little better at night because of it. I will definitely be upgrading to the heavier 2.0 brace as soon as they're out - and use it even after I get the way-too-heavy HD clutch out of my car. Thanks for doing this project Flash!

Partial Post: Please Login or Register to read the full post.

[wiseman]

I found the same issue..............would have never known it was there unless I really looked hard with a flashlight and had the wife push the peddle in and out. Installed the brace and even then the brace flexes, which is a testament to how much force there is on that Master Cylinder..... but I know I'm safe now. I will also go with the new brace when Flash is done and have a permanent fix. I will say this though.............I have read about that small crack since Flash designed the brace and never gave it a thought. Clutch was fine, pressure was fine etc..............BUT........sure enough, it was there. If you have not looked into checking this out, I would today. The small amount that the kit costs and the 30 minutes it takes to install it is nothing compared to the mess you could have if you let it go.

I did find that using a 1/4 inch drive and socket worked well installing the bracket.

Partial Post: Please Login or Register to read the full post.

[flash]

yeah - it only limits not eliminates the flex - how much it reduces it is easily measured (assuming you have 2 people) - but, you have to remember that you have nearly 3000# of resistance at the pressure plate



the new one will do more, but as i have not tested it, i can't say yet how much, or if it will be a true "cure" - i had given up on doing new projects, but as i have to have some other stuff made anyway, i can knock out a prototype and test it

Partial Post: Please Login or Register to read the full post.