Tunnel photos needed

Anyone have a photo of the tunnel area? 1966 series 1 ots or similar. I believe the hand brake cable goes through the brackets on the left side. I want to be sure I get anything else that goes through that area installed before I put in the driveshaft and rear diff assembly.

Does this work? The only items that exit the rear of the tunnel are the emergency brake cable and the drive shaft.

Yes assuming they haven’t rusted away, they’re pretty apparent on the left side. They require grommets so they don’t cut into the cable sheath. I know there is one in the back. I can’t recall if there is one in the front or not. Since it’s attached to the brake handle mechanism it might not be needed there.

Interesting, looks like you put dynamat or equivalent inside the tunnel. I was figuring on using it on the interior floor and inside the doors.

What if Dynamat is used on the inside/underside of the tunnel as well as covering the tunnel on the inside of the car? Any extra benefit to be gained from that?

It’s a heat reflection/insulation product made by DEI. I lined the entire tunnel from the engine compartment to the exit you see in my earlier photo.

I am also using an acoustic/thermal insulator on the cockpit internal surfaces to help with the noise/heat issues.

Here is a good photo that shows the tunnel and E brake cable bracket. The rings are rubber grommets that had fallen off there mounting points.

  1. Did you research whether DEI’s product is better than Dynamat?
  2. Still not sure that I understand the benefit of the heat shield in the tunnel. There is just a driveshaft spinning in there. The heat should be below that from the exhaust.

I’m sure heat rises into the tunnel when stopped.

They are two different materials designed for different applications. The DEI material is specifically designed to reflect heat away from the surface it’s attached to as well as insulate the surface. The Dynamat is a sound-deadening and insulation material. The tunnel will carry some of the airflow from the engine compartment to the back of the car when moving as well as heat soak while stopped ( as Erica mentioned). I used the DEI in the tunnel to keep (as much) heat from getting to the cockpit metal and I used a Dynamat-type material on the interior surfaces of the cockpit. Controls both heat and acoustics.

I sure hope it’s not just to reflect or this isn’t going to work very well :wink:


I think the general idea is to have the shiny side facing the heat source - though the DEI will still have an insulating layer either way.

I’m not a careful enough driver to do what you did - as evidenced by the scrapes on the bottom of my down pipes and mufflers. Speed bumps, curbs (instead of curbs cuts) and those raised fill ports in gas stations are what usually get me.

There is a definite benefit: an uninsulated tunnel gets quite hot, due to a combination of radiated heat from the mufflers, coupled with hot air, flowing through from the engine and gearbox.

Oh I’m gonna get got for sure. I’m resigning myself to considering it sacrificial and try not to pout when it happens.

With a small fee for fabbing, one can get a thin sheet of stainless, fashioned into a pan, of sorts (see me waving my hands? © Schmedley), then welded to the clamps.

Better to sacrifice the pan than the insulation!

Absolutely it does. All one needs to do is touch the proximal end of the parking brake handle to understand how much heat is in that tunnel. I just applied Eastwood’s X-Mat on the passenger compartment side of the tunnel and it made a huge difference.

As for the mufflers, I’m trying to understand the advantage of insulating the side facing the road.

Ease of installation: you could just insulate the top and sides, but it would require some scheme of attachment, not as simple as wrapping the whole shebang.

I fabricated the aluminum honeycomb full belly pan depicted in the photo (insulation padding sandwiched between the “pan” and the bottom of the car), ceramic coated the entire exhaust system and the transmission cover, and lined the transmission area of the tunnel (except for the small diameter portion for the prop shaft as I was afraid of a disaster if the adhesive or the fiberglass padding failed). Helped a lot, but still installed AC (3.8FHC).

By the way, there’s a thread in the UK upgrades section that depicts a heat shield above the mufflers only. Can’t recall the name of the company that sells them.




I don’t think you should wrap the mufflers. You aren’t trying to contain the heat, just keep it from radiating upward. You want the downward facing surfaces exposed to dissipate heat.

Got it, will do as shown.