Firewall crack repair

Maintenance advice to keep your Spider in shape.
kmoses
Posts: 366
Joined: Thu Sep 11, 2014 10:28 pm
Your car is a: 1979 Spider 2000

Firewall crack repair

Postby kmoses » Thu May 07, 2015 11:24 pm

While checking my spider for stress cracks at the firewall where the clutch cable enters the drivers compartment I found this;
Image

After digging into this attempted repair I found the firewall had been repaired with brazing rod and riveted steel plates.
I ended up cutting out everything that was questionable and ended up with this.
Image

I was not wild about welding so close to fuel lines so I machined steel plates that bolt on each side of the firewall.
Image

After machining the clutch mount hole it will be sprayed with epoxy primer, installed with seam sealer and painted along with the engine bay. The socket head screws will be changed to button head screws for a cleaner look.
Last edited by kmoses on Thu Sep 21, 2017 4:44 pm, edited 1 time in total.

AriK
Patron 2018
Patron 2018
Posts: 1148
Joined: Sat Apr 02, 2011 7:58 pm
Your car is a: 1979 Fiat Spider
Location: Montreal Canada

Re: Firewall crack repair

Postby AriK » Fri May 08, 2015 6:37 am

Nice solution, thanks for posting. We all should be keeping a closer eye for fatigue cracks anywhere on our middle aged cars. It may be surprising what we discover.

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seabeelt
Patron 2019
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Posts: 1612
Joined: Tue Feb 19, 2008 4:22 pm
Your car is a: Fiat Spider - 1971 BS1
Location: Tiverton, RI

Re: Firewall crack repair

Postby seabeelt » Mon May 11, 2015 2:38 pm

Nicely done sloution without having to weld
Michael and Deborah Williamson
1971 Spider -Tropie’ - w screaming IDFs
1971 Spider - Vesper -scrapped
1979 Spider - Seraphina - our son's car now sold
1972 Spider - Tortellini- our son's current

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v6spider
Posts: 1035
Joined: Tue Feb 28, 2006 6:57 pm
Your car is a: 4.3L V6 Powered 1972 124 FIAT Spider
Location: Mount Vernon WA

Re: Firewall crack repair

Postby v6spider » Mon May 11, 2015 6:39 pm

For my spider I designed a strengthening plate in CAD and had it cut out in 1/8" aircraft grade stainless steel. It mounts behind the firewall and is held in place by the brake booster bolts. I riveted the plate where the cable comes through to my backing plate.
If you are interested I can get the CAD file and send it to whoever needs it.
Image
Image
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http://www.v6spider.com
4.3L V6 Powered 1972 124 FIAT Spider

kmoses
Posts: 366
Joined: Thu Sep 11, 2014 10:28 pm
Your car is a: 1979 Spider 2000

Re: Firewall crack repair

Postby kmoses » Wed May 13, 2015 8:08 pm

That is a nice clean repair you did, thanks for the offer but your firewall doesn't look quite like my '79. What year is you Spider? I do have a question about the clutch cable plate that you attached with rivets, were they riveted on from the factory or did you cut one from a donor car? The reason I ask is that I have never seen a firewall that has not been repaired.

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v6spider
Posts: 1035
Joined: Tue Feb 28, 2006 6:57 pm
Your car is a: 4.3L V6 Powered 1972 124 FIAT Spider
Location: Mount Vernon WA

Re: Firewall crack repair

Postby v6spider » Thu May 14, 2015 12:57 am

kmoses wrote:That is a nice clean repair you did, thanks for the offer but your firewall doesn't look quite like my '79. What year is you Spider? I do have a question about the clutch cable plate that you attached with rivets, were they riveted on from the factory or did you cut one from a donor car? The reason I ask is that I have never seen a firewall that has not been repaired.

Mine is a 72.. The plate was spot welded from the factory. What I did was preventive because my previous spider v6 conversion car , which was a 74 cracked where yours did. The backing plate will work on any spider. The earlier spiders like mine had a Reenforcing plate on the fire wall. I added the rivets to connect that part to my backing plate.. My clutch is a 10" diameter clutch intended for a chevy v8 camaro with a 4 speed. The pressure is probably twice that of the stock spider clutch so the modification is absolutely a necessity. My engine is a carbureted Chevy vortec 4.3L v6 with over 300hp . my trans is a Borg warner t5 .. The posi rear end is out of a Mazda Rx7 gsl .

Cheers!
Rob
http://www.v6spider.com
4.3L V6 Powered 1972 124 FIAT Spider

kmoses
Posts: 366
Joined: Thu Sep 11, 2014 10:28 pm
Your car is a: 1979 Spider 2000

Re: Firewall crack repair

Postby kmoses » Thu May 14, 2015 7:13 am

Wow! that's some serious power to weight ratio you have there Rob. I'd say you now have more of a GTA (Ground Type Aircraft) than a Spider. :)

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v6spider
Posts: 1035
Joined: Tue Feb 28, 2006 6:57 pm
Your car is a: 4.3L V6 Powered 1972 124 FIAT Spider
Location: Mount Vernon WA

Re: Firewall crack repair

Postby v6spider » Thu May 14, 2015 12:11 pm

kmoses wrote:Wow! that's some serious power to weight ratio you have there Rob. I'd say you now have more of a GTA (Ground Type Aircraft) than a Spider. :)

And fun as hell!
Image

More pics at http://www.v6spider.com

Cheers!
Rob
http://www.v6spider.com
4.3L V6 Powered 1972 124 FIAT Spider

kmoses
Posts: 366
Joined: Thu Sep 11, 2014 10:28 pm
Your car is a: 1979 Spider 2000

Re: Firewall crack repair

Postby kmoses » Thu May 14, 2015 7:50 pm

That's nice. It reminds me of when I was young and was told/asked by a engine builder
"speed cost money son, how fast can you afford to go". Then as now I responded "I can afford to go fast, just not that fast".

Madmic
Posts: 1
Joined: Fri Jul 07, 2017 6:52 am
Your car is a: Fiat 124 Spider CS1 1975

Re: Firewall crack repair

Postby Madmic » Fri Jul 21, 2017 6:59 am

Hello,

i'#m new to this Forum and I have a cracked Firewall.
Sadly I can't reach v6spider. does anybody still have the drawings and can send them to me?
That would be great.

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v6spider
Posts: 1035
Joined: Tue Feb 28, 2006 6:57 pm
Your car is a: 4.3L V6 Powered 1972 124 FIAT Spider
Location: Mount Vernon WA

Re: Firewall crack repair

Postby v6spider » Fri Aug 04, 2017 4:32 pm

Hi fellas,

Sorry about the delay checking in here... I have been looking for the cad file i had upgraded my computer and transferred the files. At any rate, i am having issue locating the cad file.. still looking though i may have to contact my buddy at the waterjet shop and see if they have a copy of it..

Appreciate your patience.. :)

Thanks!
Rob
http://www.v6spider.com
4.3L V6 Powered 1972 124 FIAT Spider


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