March 29, 2024, 10:00:17 AM

Author Topic: Replaced the frame rails and reinforced the pinch welds on my FC.  (Read 6921 times)

Offline eyeoutthere

I just got done replacing the frame rails and putting 1”x1” tubing along the pinch welds.

Few questions:
  • Is there anything else I should strengthen up before I paint? I see some people put outriggers attached to the frame rails but I don’t know what the benefit is.
  • What’s the best way to strip the existing under coating? Take a wire wheel to the whole thing? Chemical strippers? Something else?
  • What’s the undercoating of choice these days?

Here is what I have done so far…

Sound deadening needs to come off.


The undercarriage. Frame rails are pretty beat up and the pinch welds are bent over flat in some spots.


Looking pretty gnarly underneath. Those are the crappy patches I put on 7 years ago when I was in college.


Cut holes for the new rails.


Cut out some more rusty spots.


cutting out the rust.


note how mangled the pinch weld is. There was a lot of cutting and bending things back into place.


Fender bolts were frozen too. That panel will be replaced


New rails made from 2.5”x2.5” tubing. These will stick above the floorboards by about 1/2".
This one is for the driver’s side. Note I tapered it down by 1/2" so it won’t intrude into the driver’s side foot-well.
I welded both ends shut before installing.


There is a bunch of pics missing but here is everything all done.
It took me a while, largely because of the rust spots.







The tubing behind the pinch welds should be able to support a jack without bending, but I’ll use my beefy new frame rails instead.

Offline digitalsolo

Re: Replaced the frame rails and reinforced the pinch welds on my FC.
« Reply #1 on: September 07, 2013, 07:55:29 PM »
I did the outriggers on mine to pick up the rollbar and to use as jacking points.

Nice work, if I did mine again, I'd do it just like you did.
Blake MF'ing McBride
1988 Mazda RX7 - Turbo LS1/T56/ProEFI/8.8/Not Slow...   sold.
1965 Mustang Coupe - TT Coyote, TR6060, modern brakes/suspension...
2007 Aston Martin V8 Vantage - Gen V LT4/TR6060, upper/lower pullies, headers, tune.
2021 Tesla Model 3 Performance - Stock...ish.

Offline largeorangefont

Re: Replaced the frame rails and reinforced the pinch welds on my FC.
« Reply #2 on: September 07, 2013, 08:30:26 PM »
Excellent work...
Quote from: cool
Sell it to spacevomit.  He'll finish it.

Offline WannaBeFast

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Re: Replaced the frame rails and reinforced the pinch welds on my FC.
« Reply #3 on: September 07, 2013, 08:36:11 PM »
Yea thats very nice.

Offline Bowtie7

Re: Replaced the frame rails and reinforced the pinch welds on my FC.
« Reply #4 on: September 07, 2013, 09:32:16 PM »
Very nice! If I ever do another FC race car you can consider that idea stolen!
I liked it when Blake did his car and remember how much when I see this.
« Last Edit: September 07, 2013, 09:38:13 PM by Bowtie7 »
I do love what I do!

Offline Supe

Re: Replaced the frame rails and reinforced the pinch welds on my FC.
« Reply #5 on: September 08, 2013, 03:16:05 PM »
Very nice.  Mine are f*cked up far worse than yours were (pretty sure PO curbed it hard, it even bent the seat crossmembers up about an inch), but the GTA rules won't let me add any sort of "stiffeners" to the underbody, so unless someone made OEM replacements, I'm SOL.   :(