Heater Boxes with an A-1 Sidewinder Exhaust

I have an A1 with flanged heater boxes.  I think they're just pipes passing through the boxes and don't have the internal heat exchanger fins as they don't produce a whole lot of heat, but it's usually adequate for the weather we have here in coastal SC.

Hi Lane,

Mine are actually original VW heater boxes with the fins and all.  They are the 1 3/8 jobs just for cool weather driving.  What kind of hose do you use beneath the tinware to connect to the air inlet of the heater boxes you have?

It's the flexible metal stuff - uninsulated - which is another reason the heat is minimal.

Maybe you just need that little metal connector pipe?  I've only seen the tan or silver pipes to the shroud.

A lot of the vw heating system is missing in most speedster replicas.  First, many of the engines don't have the thermostat and thermostat flaps so the engine takes longer to warm up.  Second, even with original vw heat exchangers on the exhaust pipes from the # 1 and #3 cylinders, Speedster replicas usually don't have the insulated heater to body hose shown in the above diagram.  Third, the sport exhausts that are put on speedster replicas lack the small heat exchangers surrounding the # 2 and # 4 exhaust pipes that are on stock VW mufflers. 

Anyway, run VW "fresh air" hoses all the way through the tin to the heat exchangers.  You may have to make a short slit along the side of each hose where it meets the heat exchanger to get them to fit.

 

Ted and Greg,

Yeah, I thought about that.  The fresh air hose above the tinware (in the upper engine bay) is the corrugated cardboard stuff.  I  have no problem with using that above the tin but below it'll be exposed to the edge of the header pipe and I figure it'll burn.  I have the transition/connector piece that goes through the tinware and, as Ted mentioned, no preheater chamber attached to the muffler that gets connected to the heater box.  

I guess I need a flexible metal hose to make the connection from the connector that goes through the tinware to the heater box. The stuff that CIP sells, for instance, is actually coated in plastic and is suitable for the engine compartment but not for below. Does anyone know where to get a 2" I.D. hose that can take the heat and is flexible enough to bend a tight radius to make the connection?  I know there has to be a bunch of guys out there who have worked this out and sourced the parts.  BTW, I already tried flexible exhuast hose and its too rigid and has a bend radius that is too large.

Thanks! 

Check out Aircraft Spruce's website. Look for scat tubing. We use that as carb heat air tubing and it runs right off the exhaust pipe.

Pegasus Auto Racing Supplies carries neoprene (300*) and high temp silicone (600*) flexible air duct hose in a variety of sizes. Just to be sure and because I only want to buy once, I used the high temp silicone, which comes in a orange/red color only. I'm using it on 1 5/8" Gene Berg heater boxes. Probably installed it 10 or 12 years ago and have had no problems. Bring your wallet. Good Luck, Have Fun!

 

JSchlotz,

Where exactly are you using this silicon hose?  On the outlet of the heater box to the body or the inlet near the 2 and 4 cylinders?

Thanks. Frank.

I have the aluminum hose but mine isn't plastic coated. The 1-3 side runs right up against the rear header tube and it is slightly singed after 400 miles but not bad enough to worry about.

Frank,

Where did you get the non-coated tubing.  I've been trying to find something metal.

Thanks,   Frank

Frank C. posted:

Frank,

Where did you get the non-coated tubing.  I've been trying to find something metal.

Thanks,   Frank

http://www.cbperformance.com/P...asp?ProductCode=1985

We have a very stiff (yet flexible) non coated pre-heat tube manufactured specifically for us.  2" ID and suitable for heater box plumbing.  We have it made it 10' sticks so you don't have to join together the 3' aluminum foil grade sticks that are available elsewhere...

I'm using the high temp silicone air duct hose on the outlet of the heater boxes to the body. The original flexible aluminum hose was prone to cracking and did not hold up well under the car, especially with all the twists and turns in my application. I wanted to do it right and only do it once. Your mileage may vary.

Would a piece of fiberglass heat shield tubing or tape on the fresh air hose protect it? 

Get Carey's from him. Save yourself worlds of grief.

Unfortunately we were just informed that Clevaflex (previous manufacturer) was acquired by Federal Mogul and this was a small volume part they are no longer interested in making...  eeeefffffff.  Back to the drawing board.

That was the plan, Stan, but Carey is out of luck also.  I fit up some of the cheapo tin foil stuff for now and made a dent in it near the header pipe to create some space.  I'm sure it'll impeded flow but...

I did find some stainless hose from a local industrial supplier but it was too rigid to make the compound bends required.  If anyone else has any ideas let both Carey and I know. He's gonna need it more than me for the long run.

Maybe look at Summit Racing -  Jeg's Racing ?

I spoke with a few other companies, butt in smaller volumes they want almost $10/ft to make it. 

We did manage to secure the little bit of old stock that was left, so I'll have a few sticks available in a week or so, but when it's gone it's gone...

 

What about McMaster-Carr?  Lots of options for duct hose.

http://www.mcmaster.com/#duct-hose/=10nhnwy

Yup James. Right you are sir. They have some 2inch stuff in aluminum and stainless.  Ever tried this stuff Carey?

No, their hoses that have a high heat range run $12+ a foot.  

I have the set up mentioned, and I replaced the original light foil hoses which were splitting, with the black stuff.  It is not cardboard, and seems to be more robust than the other tin-foil-like stuff that was there before. Top-side all is good, the pipes attach well and look fine.  Below the water (tin) line, finagling the hoses to get by the header pipes and on to the heater box stub is a pretty good bitch to do.  The pipe needs to be squished a bit here and there to make the turns.  It is clearly not optimal, but it does work.  While not always very hot, the air in plentiful, and will take the chill off.  Coldest I've used has been about 40F.  Hopefully, with better fitting side-curtains now in place, things will be even better.  Also, I have heated seats . . .

https://www.aircraftspruce.ca/...log/appages/scat.php

This is a link to Aircraft Spruce's carb / cabin heat hose. I should have said above that it can be run off an exhaust flange/ heat muff rather that right off the exhaust pipe.

Got an aircraft maintenance facility nearby ?  Check them out and ask if they have any.

David & Fraz,

I think I'll go David's route and pipe the air directly from the heater box to the 'B' pillar/door jamb upright.  I got home a short time ago and went for a ride (it just started snowing) and I could feel a good breeze coming from the defroster vent outlets, under the dash left and right, and got a very old familiar 'smell' of VW heat.  The temperature, though, was not warm but not cold either after a short ride.  It has been suggested that, due to the route the air has to take throught the frame (I have an older CMC) that it has too much time to cool.  I think it was David that shortened the route to about 2 feet from the heater box outlet directly into the car.  I really just need heat to take the chill off as I dont anticipate having to defrost.  His plan seems simple and direct.  Ive been trying to find 2" inlet round louvered vents that I can put in the door jambs then maybe use the SCAT hose noted above.

X2 on David's method. I did the same and it heats up faster than my WC daily driver. You sacrifice defrost, but the defrost you'd have is not much of a sacrifice.

> On Jan 12, 2016, at 6:45 PM, SpeedsterOwners.com <**************> wrote:
>

Frank C. posted:

David & Fraz,

I think I'll go David's route and pipe the air directly from the heater box to the 'B' pillar/door jamb upright.  I got home a short time ago and went for a ride (it just started snowing) and I could feel a good breeze coming from the defroster vent outlets, under the dash left and right, and got a very old familiar 'smell' of VW heat.  The temperature, though, was not warm but not cold either after a short ride.  It has been suggested that, due to the route the air has to take throught the frame (I have an older CMC) that it has too much time to cool.  I think it was David that shortened the route to about 2 feet from the heater box outlet directly into the car.  I really just need heat to take the chill off as I dont anticipate having to defrost.  His plan seems simple and direct.  Ive been trying to find 2" inlet round louvered vents that I can put in the door jambs then maybe use the SCAT hose noted above.

I couldn't find Aircraft Spruce's link to the flanges that I used to hook the hoses up to but they look like this : http://www.robbinswings.com/Flanges.htm   . Tom  picked up on the idea and Carey at Beck did a real nice job of installing the simple system for him. If I recall, Carey found some nicer flanges more appropriate to an automotive interior.

Perhaps Tom or Carey could share that source.

I'll leave it Carey for the details, but he used their standard round vents. He'd probably sell you a pair. Heck, you could probably by mine since I'm going WC this winter.




Tom Blankinship
313-467-5078
> On Jan 12, 2016, at 7:30 PM, SpeedsterOwners.com <**************> wrote:
>

The biggest benefit from bypassing the frame is the increased airflow.   At least that is the case on a Vintage or JPS Speedster.  I'm not familiar with the routing on a CMC.

https://youtu.be/IhnvnspQ-TE

I rarely venture out with snow on the ground. We are having a real winter this year. I put an entire new front end on a few weeks ago. I went out to get an alignment today. 34F at 11:00am. I installed the frame bypass, thermostat and flaps, and thermostat controlled oil cooler a couple of years ago. After about 10 minutes of driving I was comfortable and had to turn the heat down. The downside to the bypass it it doubles the engine noise in the cockpit. Small price to pay for heat and defrost. 

Tom, David and Troy,

I was surprised at the amount of airflow I could feel coming through the defroster frame /tube outlets under the dash.  If I could get that to reach the interior sooner I would hope I could feel it sooner.  And David's solution would also bypass the usual VW route which, in my car, includes the footwell vent area  where I found cracked acorn shells.  Someone went up the uncovered inlets underneath the rear seat area and made a home in there at some point in the past.  Sure they did all their business so a bypass could avoid disturbing all of their previous emissions etc.

I was looking for the louvered vents, round, between 2 and 2 1/2 inches in diameter for the inlet. On eBay I found round vents that are trimmed in chrome(plastic).  The nicer vents could be pushed shut but most used parts for other cars don't give measurements like the aftermarket/hotrod stuff does.  Interesting though since they could just be poked through the jam.  Kinda excited but snow tonight so this project may not see an real action until Spring.

By request on a few builds I did I ran the heater box hose directly into the frame horns ( properly reinforcing them) allowing the center tunnel to act as duct work and installing a 2.5 round vent on either side of the tunnel just forward of the seat..it gets hot !

Frank C. posted:

Tom, David and Troy,

I was surprised at the amount of airflow I could feel coming through the defroster frame /tube outlets under the dash.  If I could get that to reach the interior sooner I would hope I could feel it sooner.  And David's solution would also bypass the usual VW route which, in my car, includes the footwell vent area  where I found cracked acorn shells.  Someone went up the uncovered inlets underneath the rear seat area and made a home in there at some point in the past.  Sure they did all their business so a bypass could avoid disturbing all of their previous emissions etc.

I was looking for the louvered vents, round, between 2 and 2 1/2 inches in diameter for the inlet. On eBay I found round vents that are trimmed in chrome(plastic).  The nicer vents could be pushed shut but most used parts for other cars don't give measurements like the aftermarket/hotrod stuff does.  Interesting though since they could just be poked through the jam.  Kinda excited but snow tonight so this project may not see an real action until Spring.

Let me know if you want more info on my Beck ones.  I'm sure Carey will help.  They're black plastic and have veins that open and fully close and you can rotate to direct the airflow.  I doubt you could do much better than the design.

Im moving to a heater core under the center of the dash that will dump hot air down and plumbed to the defrost vents, as well.

Tom,

Yes, information and photos if you have any would be much appreciated.  I've seen a few that I've liked on-line but they are OEM fitments to trucks and whatnot and make no references as to inlet diameters so its difficult to judge actual sizes.

Like El Frazz I also modified the side curtains. They are a bit of a PITA to close from inside, but the difference is amazing. Very cheap mode. I purchased the material and piping from Kirk. My boat canvas guy made a template from cardboard cut and stitched the extension for $20. Of course he makes up for it on my boat. I also purchased the bypass piping from the heater boxes from Kirk. This is a very cheap mod and I have more heat than you will ever need. Regardless I try to avoid driving in the cold. El Nino has officially arrived and it has snowed almost every day for a month and no let up in site. 

An update:  I noticed my foil hose is plastic covered but it still hasn't seemed to burn much even though it is pushed up hard against the header. My car has the hose ran thru pvc pipes along the rockers and I get a LOT of air flow. It's not hot but warm enough to heat the car pretty well. I don't think you will get much more heat out of the high flow heat exchangers and it does a good job of piping the engine noise into the car!