Heater Duct Modification

Andras · 10-20-2004, 05:54 AM

Have read the posts about the John Walker heater duct modification, and marvel at John's patience, but more importantly at his skill. Nice work!

But for those of you who don't live in Seattle, you can also modify the left side heater duct to clear the distrributor by just heating (to a nice cherry glow) the duct at the area of the distributor, and then using a 2" diameter steel pipe and gently beating the part while still hot, to make the indentation to clear the distributor.

You'll have to powdercoat it once you've finished, for the propane torch burns off the old paint, but at least you don't have to cut and weld on new sheet metal.

Minimum cost, maximum effect.

Rot 911 · 10-20-2004, 05:58 AM

Andras, it is even easier than that. I did the backdate and all I did was first use a marker to outline where the distributor hits up against the duct. Then heated up with a torch and used the rounded end of a ball peen hammer to hammer in the area that was interfering with the distributor. Only needs to go in about 1/2". Took me all of 10 minutes start to finish. Then spray painted black and installed.

v9ff · v9ff's Garage

You guys have pics on how yours look?

Andras · 10-20-2004, 07:51 AM

Here is a picture of the before and the after shot, but I'm not sure how much you can see. The heater duct is "under" the ignition wires, and might be "hidden".

But all you'd have to do is "indent" it a little more than it already is, thus clearing the distributor.

juanbenae · juanbenae's Garage

to expand on kurt's advice, the distributer hides the carnage of the hammer use quite well.

additionally my 78 (air pump equiped) really did not need the additional shroud for the left side. i could have bushed down the original one to run duct directly from it through the engine tin to the exchanger. i do not know if the 83 shroud is different because of the lack of air pump, but in hindsight i only really needed the right hand side parts. i went ahead and installed the new parts i had bought anyway.

i got the full compliment of parts, but the tin that runs along the valve cover was not required on my sc either. it is my understanding that the carerras need that tin replaced too so the ducting can be routed to the exchanger.

Rot 911 · 10-20-2004, 05:19 PM

A couple of pics of my modified tin (prior to final painting)

Andras · 10-21-2004, 03:41 AM

Hi Kurt,

That looks pretty much how mine looks, even though I used the "bigger pipe" approach.

I was concerned about hammering on cold sheet steel, and thus thought to heat it up prior to smacking it with the pipe. I had thought that bending heated steel was going to create less stress on the metal than bending (dimpeling) with a ball peen hammer.

Also, since I was in the process of getting all my black sheet metal powder coated, this was just one of many pieces. Hopefully, all of that nice black stuff will continue to leeok good in years to come.

Isn't it great how there are many solutions to any one problem?

Cheers!!