How to fix burned-through floorpan? - ZR-1 Net Registry Forums

VetteMed · 07-29-2009

Background: 91 ZR-1, headers, no cats, straight pipes from headers back to mufflers - no resonator.

As I was gutting the interior from my 91, I found that the passenger side corner, where the floorpan meets the trans tunnel as it widens for the bellhousing, was burned by the exhaust, in approximately a 1" diameter circle. It was not burned entirely through, but all that remained was fiber strands, no hard substance at all. The carpet padding overlying it was completely disintegrated. I never smelled anything burning, so this may have happened when the previous owner had the exhaust done, I have no way of knowing.

So, what to do? Obviously I need to patch the hole, but more importantly, I suppose I need to fabricate a heat shield? Or do I just have a muffler shop bend the pipe a little?

What should I use to patch the floor pan?

Thanks!
Andrew

Jagdpanzer · 07-29-2009

Sorry about the bad luck.
Can you post some pics?

VetteMed · 07-29-2009

And in this one, you can see the offending pipe.

Jagdpanzer · 07-29-2009

Pick up a fiberglass patch kit at your local auto or marine supply store, trim out the burned area and fix it like plugging a hole in a fiberglass boat hull.

secondchance · 07-29-2009

Hole looks small enough (looks like about 1/2" hole?) where a temporary back up underneath with duct tape (attached to outside of car) and fill w/ epoxy mix. I think existing fiberglass strands would function to bridge the patch.
I would definitely rework the exhaust pipe to increase the distance to body. I have not looked carefully under this area while the car is on a lift so I am not sure. Does anyone know if there is a heat shield below?

Jagdpanzer · 07-30-2009

The burned area is ajacent to the front exhaust spring hangers. There are no factory installed heat shields in this area as you find outboard the cats.

07-29-2009	#1
VetteMed Join Date: Mar 2009 Location: Orlando, FL Posts: 1,828	How to fix burned-through floorpan? Background: 91 ZR-1, headers, no cats, straight pipes from headers back to mufflers - no resonator. As I was gutting the interior from my 91, I found that the passenger side corner, where the floorpan meets the trans tunnel as it widens for the bellhousing, was burned by the exhaust, in approximately a 1" diameter circle. It was not burned entirely through, but all that remained was fiber strands, no hard substance at all. The carpet padding overlying it was completely disintegrated. I never smelled anything burning, so this may have happened when the previous owner had the exhaust done, I have no way of knowing. So, what to do? Obviously I need to patch the hole, but more importantly, I suppose I need to fabricate a heat shield? Or do I just have a muffler shop bend the pipe a little? What should I use to patch the floor pan? Thanks! Andrew

07-29-2009	#2
Jagdpanzer Join Date: Apr 2007 Location: Northern VA Posts: 2,661	Re: How to fix burned-through floorpan? Sorry about the bad luck. Can you post some pics?

07-29-2009	#3
VetteMed Join Date: Mar 2009 Location: Orlando, FL Posts: 1,828	Re: How to fix burned-through floorpan? And in this one, you can see the offending pipe.

07-29-2009	#4
Jagdpanzer Join Date: Apr 2007 Location: Northern VA Posts: 2,661	Re: How to fix burned-through floorpan? Pick up a fiberglass patch kit at your local auto or marine supply store, trim out the burned area and fix it like plugging a hole in a fiberglass boat hull.

07-29-2009	#5
secondchance Join Date: Aug 2006 Location: McLean, VA Posts: 3,723	Re: How to fix burned-through floorpan? Hole looks small enough (looks like about 1/2" hole?) where a temporary back up underneath with duct tape (attached to outside of car) and fill w/ epoxy mix. I think existing fiberglass strands would function to bridge the patch. I would definitely rework the exhaust pipe to increase the distance to body. I have not looked carefully under this area while the car is on a lift so I am not sure. Does anyone know if there is a heat shield below?

07-30-2009	#6
Jagdpanzer Join Date: Apr 2007 Location: Northern VA Posts: 2,661	Re: How to fix burned-through floorpan? The burned area is ajacent to the front exhaust spring hangers. There are no factory installed heat shields in this area as you find outboard the cats. Last edited by Jagdpanzer; 07-30-2009 at 11:35 AM.