Airhandling

Superman · 10-22-2001, 09:14 AM

I'd like to convert my SC to eliminate the blower and three big hoses. Instead, I'd like to get the early side plates that feed the heat exchangers directly. It looks like I will be able to go to backdated (pre-'74) heat exchangers.

What parts will I need for this conversion, and what problems will I need to solve? For example, will the engine sheet metal need to be changed, in addition to the early side-plates because the early HEs are fed from a different angle? And finally, where can I get the (used) parts?

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'83 SC

BenWillis · 10-22-2001, 10:49 AM

Try here...... A complete list of the required parts and instructions on the change over.

Click here

Ben in SC

Superman · 10-22-2001, 11:13 AM

Thanks, Ben. Sounds simple. I'll study it a bit longer to see if I can identify the parts needed. I think it is saying that the right cover plate needs to be changed, but the left cover plate stays the same, just with a different duct piece. I think that what I am seeing is that there is a relatively small, somewhat simple plastic (left side) duct piece that costs about $150!!!!!! That's obscene to a cheapskate like me. But I never use my (unplugged) blower and I get all the heat I want. So, it would be very, very nice to clean up this engine compartment.

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'83 SC

Early_S_Man · 10-22-2001, 11:42 AM

Hey, Super!

With a salvaged cooling shroud assembly from a VW Beetle boneyard ... and some creative tinsnip work and welding or pop rivet work you might not have to spend the ouragious coin for the new ducting! As far as the side lateral tin with relocated holes ... wouldn't that be a good project to put some Titanium sheet from the Boeing candystore to use? Hammer and a 2x6 'buck' might work some wonders out of that 0.040" sheet Ti!

Take a look at the proper pieces and let the imagination go to work:

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Warren Hall
1973 911S Targa
1992 Dodge Dakota 5.2 4X4 parts hauler

[This message has been edited by Early_S_Man (edited 10-22-2001).]

Early_S_Man · 10-22-2001, 12:04 PM

This pic is not quite as 'pictorial,' but it more closely depicts the MFI tinwork on my engine ... and the two-piece lateral tin I was referring to ... #5 (without the 1" dogleg heater pipe for the MFI thermostat) is a 'mirror' image of #7, and #8 is a mirror image of #9.

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Warren Hall
1973 911S Targa
1992 Dodge Dakota 5.2 4X4 parts hauler

[This message has been edited by Early_S_Man (edited 10-22-2001).]

GeorgeK · 10-22-2001, 12:23 PM

Super,
on my '76, which I think has the same setup as your SC, I only had to source part 11 from the upper pic above, and some of that paper tubing. Worked wonders. Of course the electric engine was BROKEN inside its housing, not helping matters. Worked perfect since.
GeorgeK

pbs911 · pbs911's Garage

Super,

This is a great idea and one I have been looking into for the past few months. It seems simple and the result is well worth it. The only down side I have heard about is that you don't get mush heat at idle.

As for getting the parts used, good luck. My e-mail requests to the better known P-car dismantlers for these parts have proven futile. Either they don't know what I'm asking for or the cost isn't worth their time.

Tom, on the Rennlist board, had a set for sale when he converted to a 3.6, but I missed the auction.

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Paul
78SC Targa
Pelican Parts Members Gallery

Superman · 10-22-2001, 12:52 PM

Thanks, folks. It looks like I may become "Fabrication-Man." In Warren's first illustration (thanks, Warren), it is pieces number 10 and 11 I am worried about fabbing and worried about finding, cheap. The rest should be pretty simple. Am I right...is this the hard (spendy) part?

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'83 SC

Early_S_Man · 10-22-2001, 01:29 PM

Super,

Actualy, #10 is the plastic scoop/duct, and #9 is the vertical metal piece that secures it in place -- an easy part to make, it is flat with two tabs, period! I can send you the outline drawing to make it. Left-side piece #11 is the all metal duct-end cap that would be most feasible to fabricatefrom VWshroud. It may be possible to make #10 out of fiberglass or some nice yellow Kevlar cloth ... two pieces, top and bottom, laid over the factory part as a mold, the ntrimmed and joined to make the replacement part. Clear epoxy resin, yellow Kevlar held in place with a Titanium vertical panel ... let's see, vacuum bag it to get the best fit over the original mold. This could be s little 'artwork' in the making under the hood! Maybe a Kevlar copy of the other side would work better that cobbled-up VW-tin after all!
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Warren Hall
1973 911S Targa
1992 Dodge Dakota 5.2 4X4 parts hauler

[This message has been edited by Early_S_Man (edited 10-22-2001).]

RarlyL8 · RarlyL8's Garage

Big S -
Find a privateer 911 mechanic. He will have this stuff laying around for little or nothing. That's what I did on my '78. Only cost was for new duct hoses, old used ones were just too beat up.

Superman · 10-22-2001, 01:54 PM

Stop it! You guys are getting me all excited!

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'83 SC

Superman · 12-13-2001, 08:21 AM

I exhumed this thread because I have another question. I love my SC, but I have strong feelings about the various hoses and compressor that are right in the way when I want to work on my engine. That stuff HAS TO GO.

When I make this change, will I get some good air flow through the heat exchangers, compared to the current system? Currently, my blower motor is unplugged (I don't care about air volume at idle). Drivers' side gets plenty of heat. Passenger side heat exchanger is tired, so passenger heat is insufficient. Heat exchangers will be replaced, so hopefully the leak will be gone.

Again, my question is: Will the much simpler early system give me poorer air flow, the same, or improved air flow while driving (not idle)?

wckrause · wckrause's Garage

I can't see how it would be worse, you're getting rid of several feet of ducting, plus all of those extra bends, and the restriction caused by an in-operative blower motor. As long as the shroud openings stay about the same size, you shouldn't have any reduction in flow.

I wonder if you could do this mod, and then retrofit the footwell blowers from a Carrera to get you some defrost at idle?

Superman · 12-15-2001, 04:28 PM

Sorry for draggin this thread up again, but I have a hot news flash for you. If you don't adjust your heater boxes properly, you won't get the heat you want, when you want it.

I recall noticing months ago that the heater bos was not completely closing on the passenger side. Not thinking that a small adjustment would make that much difference, I looked unsuccessfully for a restriction. My passenger side heat does not work as well as the drivers' side.

Well, I noticed the heater box again and made the adjustment. I'll drive it tonight and I expect better passenger side heat. Sometimes I can be real lame-brained.

tbitz · 12-15-2001, 06:43 PM

I backdated the duct work when I backdated my heat exchangers on my 1978 SC. The engine bay is a lot less cluttered. I found the two ducts needed in the Pelican classifieds. Do a search in the classifieds, and email people parting the older Pcars. There were a couple of sellers when I looked. I think I paid $25 for the pair of ducts.

The heating is great when the engine is not in idle. When idling, you get a little heat, but not much. I only need the heat during fall and spring (don't drive in the winter), but here in Ottawa, Canada fall and spring is cold.

I am happy with setup. Next thing to go is the CIS. I will be doing the efi conversion that's been talked about in other posts. This should really clean up the engine bay.

Here are some photos.