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Posted by: 914ltd Oct 6 2011, 06:34 AM

I posted this last year, heating season is here again. These are big cracks, a tiny one you would not be able to hear would still be dangerous. These are not accident damaged. If you have a set on your car, grab the carbon monoxide detector from home and take a ride with the heat on and windows rolled up. There is a detector used in small aircraft also available. The last photo is how we now test for leaks using air pressure. Brad


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Posted by: mepstein Oct 6 2011, 06:43 AM

So just the shell is stainless?

Posted by: rick 918-S Oct 6 2011, 06:50 AM

Thanks Brad! I have seen a set like that. Just because you have SS exhaust does mean they are not fatigued.

Posted by: jimkelly Oct 6 2011, 06:51 AM

i believe the pipes are stainless too - a magnet should not stick - some though do have steel muffler flanges.

i assume high heat is hard on stainless ??

brad - how frequent would you say this is ??

would capping one end off and filling them with water be a good enough test ??

jim

--

Posted by: wingnut86 Oct 6 2011, 07:27 AM

Just assuming here, but is the washer/rubber dongle for a compression seal fitting for the opposite end of the hookah? If so, where did you source the rubber puck? Also, what's the max pressure for the volume and an acceptable drop over "?" Time?

Sorry for the soliloquee(sp)...



Dave

Posted by: rick 918-S Oct 6 2011, 07:40 AM

Those are available in the hardware store I think. Tighten the nut and they squish and expand. Also automotive emergency freeze plugs.

Posted by: VRROOMM1 Oct 6 2011, 07:42 AM

Posted by: 76-914 Oct 6 2011, 07:47 AM

Or in the plumbing section. aka wing nut test plug. These are great detectors and affordable. They start at $3-$4. http://www.aircraftspruce.com/search/search.php

Posted by: wingnut86 Oct 6 2011, 07:52 AM

Great responses. All noted in my broken Carolina Anglish...

Thoughts on the 2nd part of the question? I can look in the Factory manual when I get home if you guys think it's in there...

Posted by: tradisrad Oct 6 2011, 07:53 AM

I've seen a cracked one.

Posted by: dlee6204 Oct 6 2011, 08:16 AM

This is a great thing to check. Thanks for posting this.

Posted by: 914ltd Oct 6 2011, 09:04 AM

Jim The whole heat exchanger is stainless except the earlier muffler flanges. The pipes are a magnetic stainless (304?)

Posted by: SLITS Oct 6 2011, 09:14 AM

Brad, 304 would be non-magnetic as I remember. 400 or 500 series would be magnetic (more iron, less nickel - from my days in the restaurant equipment industry).

Posted by: 914ltd Oct 6 2011, 09:22 AM

SSI says the heat and salt caused this but I have heard from owners in no salt areas with this problem.
Frequency? I pitched a couple before I cut these open but I have probably sold 50 used pair since they became available in the 70's.
Any method including water should work but there is a possibility of a tiny crack not showing with air or water.

I don't have set test procedure for the air pressure, we use 10 psi, the time period until the air bleeds off mostly depends how good the test plugs work.
Be careful not to aim the expanding rubber plug (hardware store item) at anything during test! Brad

Posted by: jaxdream Oct 6 2011, 09:31 AM

One way of using this method is to hold each pluged end in a bucket or tub of water to see if the seal is leaking thereby eliminating the question if the pressure drops is it coming out of the pluged ends , kinda like the old tire puncture location test. This should be very doable for folks wanting too check their heat exchangers , great idea that I will do when the time comes to use / not use mine . carbon monoxide= DEATH. Recently some folks in a town north of me died in a RV from a faulty generator exhaust , this happened over night , next morn they were gone , 5 peeps total . Also on another trip to an event where tents were allowed , a fella , his son ,and his son's friend didn't wake the next morn because of using equipment inside the tent , dew sealed the tent so it couldn't breath and they were gone also.
Thanks Brad for posting this procedure as it may help a lot of guys as to the usability of thier heat exchangers.

Jack

Posted by: avidfanjpl Oct 6 2011, 12:11 PM

Sounds like we should see if someone is willing to make new SSHE's even though the price would be PRICEY.

Racer Chris at Tangerine?

ALL Stainless?

Something to consider.

Life is good, but CO is bad.

I don't use heat, but this scared me good. I checked mine when off the car last spring by filling them up with water and looking for leaks pipe by pipe, but it was all good, still, no fun to gas oneself unknowingly.

John

Posted by: flipb Oct 6 2011, 12:21 PM

I've previously gotten oil (from a leak) into the SSHE's. As it's burned off, I've seen smoke through the ventilation system occasionally.

The oil leak was fixed about 300 miles ago - I think/hope - with new pushrod tube seals.

If I drive around with my heat on and a CO detector, will it go off due to the remaining oil residue? Or will it actually tell me whether my pipes are leaking?

Posted by: GeorgeRud Oct 6 2011, 01:44 PM

As these cars age, things do wear out. Even things you think would last forever.
Probably time to get a simple carbon monoxide detector - this stuff can kill you very easily.

Thanks for posting this important information, Brad

Posted by: RFoulds Oct 6 2011, 02:00 PM

if you dont need the heat, simply remove the hose from heat exchange to flap box, and manually push the flap all the way closed. Or, remove the flap box too, and put a cover plate over the heat/defrost opening. No more worries.

However, if you need the heat. Move..

Posted by: ConeDodger Oct 6 2011, 02:33 PM

Some where all stainless others were not. I recall when I sold a set of brand new in box SSI heat exchangers, the buyer wanted me to check the flange with a magnet. They were all stainless but another set I had were not.

Posted by: mepstein Oct 6 2011, 03:12 PM

I'm pretty sure they are available new from Mittlemotor - pretty but pricey.

http://www.mittelmotor.de/webshop/englisch/mm.htm $1,200


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Posted by: poorsche914 Nov 11 2011, 12:21 PM

I had a 1.7 set of SSIs on my 914 and after many attempts at tightening up what I thought was an exhaust leak at the head found out the pipe has a crack at the first bend inside the clamshell (noticed this when I was looking at it at night and saw fire shooting out).

Removed that set to install a 2.0 set I have had for years and years. On the driver side unit, noticed there was a crack at the point where the pipe entered the clamshell which was caused by stress from the other end not quite lining up to the exhaust hanger. Had to be pulled over about 1/4" or so. Over time, the crack formed.

OK... on to my final set of 2.0 exchangers. No visible cracks but one of the pipes can be twisted slightly back and forth so that is also useless

Three sets of SSI exchangers... all three sets have at least one side with issues.

I was hoping to get some heat into my 914. Think I will block off the driver side and just hook up the passenger side. Then will see about having the bad exchangers repaired

Posted by: Mikey914 Nov 11 2011, 12:57 PM

A simple cheap insurance is one of these. You can pick them up and may airport FBOs (fixed base operators) for less than $5. Just look up learn to fly and your local airport and call to see if they have them. Or buy from ASA directly.

http://www.asa2fly.com/Carbon-Monoxide-Detector--P822_product1.aspx


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Posted by: 914ltd Nov 11 2011, 01:47 PM

Let me suggest you don't repair the bad SSI's. We hammered on the internal pipes on the cracked ones and the metal shattered. A repair is not worth the risk. Brad

Posted by: sixnotfour Nov 11 2011, 02:04 PM

my daily driver I switched to gas heat, Nice dry clean heat. Plus a flic a of a switch its heating no engine running.

Posted by: poorsche914 Nov 11 2011, 03:53 PM

Thanks for the warning. I haven't looked real close but the 2.0 pipe with the crack actually developed a hole so it seems it could be brittle.

Makes buying these things used a bit of a risk, doesn't it?

Posted by: GeorgeRud Nov 11 2011, 10:32 PM

If you have any pictures of your gas heater and it's installation, please share them with the group. I'm sure people would love to see them.

Also, thanks to Brad for the warning!

Posted by: bigkensteele Nov 17 2011, 10:10 PM

I just put my car back together and drove it for the first time in about 4 years. One change I made was to install 2.0 SSIs that I bought from Brad at a swap meet probably 12 years ago. I also blasted, painted, and installed a really greasy set of branch pipes and j tubes that I bought. I let them soak in my parts washer for several days, and they were still pretty nasty, and as you know, there is no way to really get to the inside completely.

Anyway, I took it out tonight to get gas. I filled it up, went in to pay, and when I came out, the cockpit was filled with smoke. It didn't really smell like exhaust, so now I am wondering if it is residual crap burning off the inside of my restored parts, or if I have leaking SSIs.

Can anyone think of a way to test them on the car?

Posted by: GeorgeRud Nov 17 2011, 10:23 PM

You could get a CO detector card, turn the heat on full with the top down, and run the car around with the card by the heat outlet to see if there is any sign of CO. Alternatively, CO detectors are available for RVs that run on 12 volts.

If you did restore the old heat exchangers, I would imagine that you will have a lot of residual stuff burning off the first few times you use them.

It pays to be safe if you're not sure.

Posted by: 69rsss Nov 18 2011, 12:50 AM

John, These are the best looking set I've seen yet I looked them up but it desnt look like you can get them in the states. Any other vendors carry these?
thanks Joe

Posted by: bigkensteele Nov 18 2011, 07:00 PM

I picked this up at HD Racing today. $28 is a small price to pay for peace of mind. I would recommend one for anyone running heat with an air-cooled engine.

http://www.homedepot.com/h_d1/N-5yc1v/R-100311681/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

I am contemplating where to put it. I may velcro it under the dash, just put it in the glove box, or place it behind my seat. From what I have read, CO mixes pretty freely with air, meaning that it is unlikely that there will be a "pocket" of CO under the dash, or up by the windshield.

More reading on CO:
http://www.faa.gov/pilots/safety/pilotsafetybrochures/media/CObroforweb.pdf
http://www.avweb.com/news/aeromed/186016-1.html

Posted by: jaxdream Nov 18 2011, 10:58 PM

Just an idea Ken , remove the heat exchanger hose on the cabin side leaving it connected to the heat exchanger . Run the engine and aux fan also to test for CO2 right off the heat exchanger itself . that should tell you if the exhaust is leaking into the clamshells, and not risk too much inhalation of fumes . Basicaly testing the air volume before it reaches the cabin. Good luck with your findings and let us know what you find.

Jack

Posted by: RobW Nov 19 2011, 05:26 AM

Thanks for posting this nugget.

We all love our 914s but no one wants to be buried in it especially while still driving down the street.

Posted by: nathansnathan Nov 19 2011, 10:25 AM

I found something similar on a pair of factory bus heat exchangers, though those have a cast aluminum heat sink around them and are steel. I had the sheet metal off of them. I put a rubber stopper in one end, modified another stopper with a cut-off a bicycle tube air valve stem for the other end. I submerged it in a rubbermaid-type container. Using a bicycle pump, there were numerous tiny cracks, fissures difficult to notice by eye that bubbles easily came out of.

Bus ones also have asbestos fiber lining all inside the sheet metal but that's another issue.

Posted by: wingnut86 Nov 19 2011, 08:35 PM

Racer Chris's custom headers with heat exchanger are looking better and better.

Chris, group buy of an even 10 units for $499.95 each?

Posted by: partwerks Nov 19 2011, 08:49 PM

One less thing for me to worry about having the WRX engine in there........

Posted by: jimkelly Mar 15 2012, 04:10 PM

my first encounter with a sshe that had a crack in the pipe within the tin area. during my test, one pipe out of four clearly had some air bypass. i cut the tin off and basically the air was escaping thru basically a pin hole along a fissure. as you can see this crack is minor compared to brad's examples. thanks to brad for pointing out the potential for this occurance and his testing proceedure.

here is a link to some info on COHb levels as read by the kiddie night hawk detector shown in a post below.

as you can see, I plug on end and tape around the head end as to have a clean surface to put my mouth on, so I can blow orally to check for leaks, works fine.

http://www.safetyproductsunlimited.com/co_alarm.html


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Posted by: bandjoey Mar 15 2012, 06:43 PM

What About the common steel HE's? Do they crack like this too???

Other Solution: Keep the roof Off.

Posted by: bigkensteele Mar 15 2012, 06:57 PM

Thanks to Brad and this thread, I don't drive with the roof on without this. It has registered as high as 33 PPM while I have been out on drives. Not much, but not zero either.

$28 at Home Depot = cheap insurance.

Posted by: 2xs performance Mar 15 2012, 07:44 PM

Great thread!

This is my first air-cooled car. I do have exhaust leak (haven't looked for it yet) and the thought of a leak coming through the heater did cross my mind but wasn't sure how to check/know for sure. The CO tester in the cab is a great ideal everyones needs to know/do. Needs to be told to all new poeple somehow. Maybe in a check list for newbies. First things to check out when getting a 914.
My 6 year old rides in the car with me. Alot at stake by not knowing.
I'll be getting one before I take my car out for a drive again!

Posted by: sean_v8_914 Jul 4 2013, 03:49 PM

2013 bump on an important thread

Posted by: michael7810 Jul 4 2013, 05:11 PM

Thanks for the bump. Today I removed my stock HXs and getting ready to install SSIs tomorrow, now I will do a leak check first.

Posted by: euro911 Jul 4 2013, 08:29 PM

I'm back to thinking about electric heaters for the air-cooled cars

Posted by: Maltese Falcon Jul 4 2013, 09:53 PM

Last year Dansk purchased the SSI brand and added the 911 HBs to their inventory.
I wonder of they are the supplier for the 914 HBs sold by Mittlemotor Deutschland ?
Anyway, the cost of liability insurance on making this product sounds higher than the mfg. wheels and suspensions
I never would have expected a high QC'd product like the SSI to fail.
Marty

Posted by: bigkensteele Jul 4 2013, 11:37 PM

http://www.homedepot.com/p/t/100311681?langId=-1&storeId=10051&catalogId=10053&N=5yc1v&R=100311681#.UdZa3fmbPyY

Posted by: euro911 Jul 5 2013, 01:17 AM

Good reviews too.

Posted by: Mark Henry Jul 5 2013, 07:04 AM

Good luck with that!

Electric heaters for VW bugs, etc. have been around since the 60's, they never work worth a shit.
Too much of a draw on the alternator.

Posted by: Jgilliam914 Jul 5 2013, 07:17 AM

I have never had that tight of a car to worry about CO or drove it often enough in the cold enough to want heat But I would be interested in seeing the gas heater in action

Posted by: GeorgeRud Jul 5 2013, 07:24 AM

Webasto and Eberspacher are the two most common ones around. VWs used them all the time, as did early 911s (they fit in the smugglers box). I've only seen pictures of one installed in a 914, and have never met anyone who's seen one in person.

They do work great, but also have the CO risk if the heat exchanger inside the unit cracks. CO monitors are the safest and cheapest way to go IMHO!

Posted by: mepstein Jul 5 2013, 07:27 AM

heated seats

Posted by: euro911 Jul 5 2013, 12:05 PM

Yeah, the 25A or 30A generators on the 356s and 912s barely support the car's needs. The 55A on the 914 isn't much of a powerhouse either.

One would need to install one of those high-amperage alternators (like Pete (pnewman) sells) to be effective.

I don't know how much current the seat heaters draw

Posted by: Garold Shaffer Oct 23 2013, 06:21 AM

Just wanted to give this thread a bump since the weather has gotten cooler here in Indiana. Thanks again Brad for great info.

Posted by: JmuRiz Oct 23 2013, 07:49 AM

All I wish is that SSI (the new one) would make some 914/6 heat exchangers....

Posted by: mepstein Oct 23 2013, 08:23 AM

There are no oem ones being made but there are a couple different types made in Europe that look promising

Posted by: mr914 Oct 24 2013, 02:12 AM

There is ferrous and non-ferrous stainless.

Best way, IMO, is to plug,tape, seal the end and apply pressure, Even with a hair dryer to see if it is leaking.

Plug the end, use the hair dryer (I have a heat gun that i use in cool mode) and see if you have air coming out of the edges of a heat exchanger. Good excuse to fire up a cigar when it is not golf season....

Posted by: Garold Shaffer Sep 24 2014, 10:07 AM

Since the weather is starting to cool off I thought I would give this tread a bump. I am getting ready for my last swap meet of the season in Cincy this weekend and going through some SSI exchangers. One out of 5 that I have leaks. I just do a simple water test. I plug the muffler end and fill the tubes with water and let them sit for 30min. doesn't take long for water to find a pin hole or crack and start to seep out. The exchanger I have that is leaking water looks great, no dents, but one of the tabs has been repaired.

Be careful when buying SSI exchangers ask the seller to do a simple water test to verify they don't leak. I will also to Brad's air pressure test on the ones that pass my water test just to make 100% sure they are fine.

Posted by: KaptKaos Sep 24 2014, 10:41 AM

Just saw this, and it may explain the leak that I can't seem to find. However, I am not running stainless, but stock exhaust. I don't run heat, so that's not an issue, but the backfire is.

Does this problem happen with the stock steel exhausts too? I assume it would, but this thread seems to focus only on the stainless.

TIA

Posted by: buck toenges Sep 24 2014, 11:48 AM

Can you do this with the hes are on the car? If not what is the best way with the heat exchangers on the car?

Posted by: GeorgeRud Sep 24 2014, 12:23 PM

If the exchangers are on the car, a simple battery powered CO detector is probably the best you can do. Even on units that test out good, isn't it cheap insurance to have one in the car?

Posted by: barefoot Sep 24 2014, 06:18 PM

I dd similar PT to the SSI's i bought from Gerald, Plugged the round outlet ends & Filled the pipes with water as full as they would go with parts tilted about 45 degrees and left for 24 hrs, no change in water level.

Posted by: euro911 Sep 24 2014, 08:42 PM

It's not an impossible issue with stock mild steel pipes, but SS is more susceptible to becoming brittle with the heat cycles.

Posted by: RobW Sep 24 2014, 09:51 PM

Yikes! Forget heat then...

Posted by: Phoenix914 Sep 25 2014, 05:51 AM

Here is a link to another battery operated CO detector. The one previously linked is discontinued from Home Depot.


http://www.amazon.com/dp/B004Y6V5CI/?tag=googhydr-20&hvadid=33861802315&hvpos=1t1&hvexid=&hvnetw=g&hvrand=2703873719984948297&hvpone=&hvptwo=&hvqmt=e&hvdev=c&ref=pd_sl_s7wc0ilmw_e


Now I'm paranoid about my SS HEs. This isn't something I had thought about previously. Thanks for this thread!

Posted by: Spoke Mar 5 2015, 01:02 PM

???


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Posted by: ThePaintedMan Mar 5 2015, 01:26 PM

That looks just like a set I bought off of Ebay... back when I didn't know any better. In theory that could be fixed. But in practice, it's not worth it... and probably dangerous.

Posted by: Garold Shaffer Mar 5 2015, 07:18 PM

Yep, had a perfect looking set of 2.0l exchangers took them off the parts car I could turn the end 180 degrees.

Posted by: nathansnathan Sep 25 2015, 04:25 PM

Whenever I bolt the heat exchangers to a motor, I check to see if they hold air by putting each cylinder to tdc and blowing into the muffler end of each port. I use a rubber stopper with an aluminum tube through it - something I made, looks like this, kind of.


This is also a good test to see if the exhaust is sealing at the head, which can be a problem, and can be done with the boxes on the car, just gotta take off the muffler.

Posted by: Johny Blackstain Sep 25 2015, 04:30 PM

Anyone have a clue as to who made them for "AA" back in 1979? Those are the ones I have & they seem to be just fine after 6k miles.

Posted by: Dave_Darling Sep 25 2015, 06:19 PM

I'm pretty sure that SSI made all of the 914 four-cylinder ones.

--DD

Posted by: SirAndy Sep 25 2015, 07:06 PM

Posted by: Johny Blackstain Sep 25 2015, 07:15 PM

Has the quality of the materials or craftsmanship on the stainless exchangers gone down over the years?
The factory exchangers rusted out after 4 years & nearly killed my Pop from CO poisoning, which is why he bought the stainless ones back in 79.

Posted by: Katmanken Sep 25 2015, 09:36 PM

Don't think so. A metalurgist for GE aircraft engines always warned me that my 914 SSI exchanger pipes would rust. He said it was due to the type of stainless tubing used.

He advised using a magnet on the tubing and the air shrouds. One was magnetic and the other was not, This was a guy used to casting turbine blades as a singe crystal and with air passages within. Never run my SSI's so still shiney.

Posted by: porschetub Sep 26 2015, 02:43 AM

The engineering term is "work hardening" the problem exists from constant heat cycling till the SS fractures,you will notice the cracks are @ the start of the bends or in the middle of 2,the tube is under more stress in these areas.
The larger outside radius is always the thinnest part of the tube.
My experiences with this problem have indicated poor quality SS or the incorrect grade used ,old age also plays a part.
To add to the problem closing the pipes in speeds up this issue that's why you don't see cracks outside the heatexchangers,many aftermarket SS systems come with a warning not to use exhaust wrap for that reason,SS pipe get very hot.

Posted by: RobW Sep 26 2015, 06:07 AM

Tangerine or headers.Not the end of the world.

Posted by: bretth Sep 26 2015, 06:36 AM

So are you saying that if it is not magnetic it is less likely to fracture? I used to work GRC years ago not with metals though. I believe 304 and up are non ferris.

Brett

Posted by: barefoot Sep 26 2015, 07:01 AM

I just checked my 1.7/1.8 SSI's and neither the tubes or the shields are magnetic which means the are 300 series SS, probably 304 one of the least expensive grades and should be good good choices. The 300 series are called 18-8 grades which is 18% Ni and 8% Chrome with most of the balance Iron.
The magnetic grades are 400 series and are just 12% Chrome balance mostly Iron. These grades can be hardened by heat treat so that's what hunting knives are made from.
BTW I pressure tested mine are are OK.
Barefoot

Posted by: 914ltd Oct 1 2015, 07:15 AM

Hey 'teeners, It's time to bring this up again. There is a lot of good information on this thread about the SSI's. Also keep in mind that CO can impair your judgment.
What might have been the root cause of a 914 accident?
Don't dismiss how dangerous this can be! Brad

Posted by: GaroldShaffer Jan 29 2019, 10:58 PM

Little late in bumping this thread. Never to late to check those SSI exchangers you have waiting to install.

Posted by: 914ltd Jan 30 2019, 08:56 AM

Thank you Garold. This IS an important thread for 914 owners. Garold or I or someone else should post this, at least, every heating season. Don't avoid using SSI's but be sure to check for CO if you do. Brad Mayeur

Posted by: dr914@autoatlanta.com Jan 30 2019, 09:27 AM

Right Dave, John Danials at Stainless Systems made all of the 914 heat exchangers back then, before he sold the operation to Dansk just a few years ago

Posted by: mb911 Jan 30 2019, 10:11 AM

This rule is for any and all heat exchangers.. Keep in mind that is the same procedure they do on all small aircraft to ensure everyone is safe..

Posted by: Dave_Darling Jan 30 2019, 11:44 AM

We have just seen an SSI on the Facebook group that had one of the two header pipes completely detach. This was obviously something that failed all the way around, and would have been leaking a massive amount up to that point.

SSIs are good, but very much not immune to problems!!

--DD

Posted by: mb911 Jan 30 2019, 12:13 PM

Nothing is..

Posted by: GeorgeRud Jan 30 2019, 05:51 PM

You can get a battery powered CO detector for $20 at Walmart or Amazon, so why not carry one in the car to be safe. Folks keep forgetting that even the best parts do eventually get old and brittle.

Posted by: worn Jan 30 2019, 07:55 PM

I have one in the car.

Posted by: StratPlayer Jan 30 2019, 08:01 PM

Who is making SS exchangers?

Posted by: mb911 Jan 30 2019, 08:37 PM

For a 4cyl no idea. For six's lots of us.

Posted by: euro911 Jan 31 2019, 02:36 AM

Hmmm ... good idea

Posted by: DRPHIL914 Jan 31 2019, 07:07 AM

I think Dansk is , they are on E-bay and AA carries them as well, George can chime in, he would know manufacturer. Also several sources for SS mufflers from European makers that now are selling on ebay as well.

Posted by: Mark Henry Jan 31 2019, 08:01 AM

Aircraft Spruce you can buy little button CO detector for around $5, good for 12 months once opened. Stick it right beside the tach.

Posted by: euro911 Jan 31 2019, 12:25 PM

Those are cool ... I'll have to get a couple of them

Posted by: 914ltd Oct 15 2020, 12:20 PM

I wanted to post this again. I was just reminded with another cracked stainless heat last week. Brad

Posted by: rbzymek Oct 15 2020, 03:22 PM

Thanks for the heads up. Just ordered a $20 battery CO detector from Home Depot. I prefer an alarm to the card type so I do not have to check it. Also it will last longer than 12 months.

Posted by: horizontally-opposed Oct 15 2020, 05:28 PM

Yikes.

This thread is a good reminder to find other solutions for a bit of heat (heated seats, "hair dryers" for a defroster, gas heater, etc) for the interior and/or an electric A/C system with heat. Cost of heat exchangers vs keeping headers—particularly on a six—is a decent head start down these roads.

Posted by: euro911 Oct 16 2020, 01:35 AM

Yep. I have a pair of 914 Rubber's seat heaters destined for the '71 914's reupholstery job ... thinking about picking up another pair for my '66 912 too

Posted by: mepstein Oct 16 2020, 06:18 AM

I disagree. Especially in places where it gets cold. Heat exchangers work great and the cars were built with them in mind. Every winter there are threads seeking alternatives that never pan out. If you plan on enjoying your car for the next 5, 10 +++ years, heat exchangers are worth the investment.

Even my stock 1.7 car without an electric fan in the engine compartment, was a joy to drive on a 20 degree winter day. Driving with the top off on a cool fall day while the heat rolls through the cabin is heaven.

Posted by: mb911 Oct 16 2020, 08:07 AM

Ask Michael about heat in his car or Steve or any of the southern Cali folks that have real heat exchangers they make the difference in the car for sure. We are actually working on a simpler hopefully cheaper heat exchanger for the -6 cars to basically mirror the driver side heat exchanger to the passenger side to save costs and bring the price down but retain fantastic heat and introduce a better merge collector at the same time.

Posted by: horizontally-opposed Oct 16 2020, 08:42 AM

I don't at all disagree that heat exchangers are effective—I enjoyed a set of SSIs on my Type IV for 20 years, and if anything they made too much heat. So I can see where they're heavenly in colder climes.

However, those pics of SSIs (which were exceptional quality...) do make me wonder about alternatives. I don't need much in the way of heat in my 914. I usually turned the heat down on cold days, and can see where heated seats and defrost would beenough. And...A/C is more and more appealing to me. I understand electric A/C systems for Emory's 356s are pretty good these days. Makes me wonder about such a system for a 914—because where I live, and for how I use my 914, a lack of A/C is the #1 thing that keeps me from taking the car on certain drives.

I've been driving my 914 with plain headers for several years now, and the times I was bummed it didn't have heat can be counted on one hand, maybe two—but I'd still like to add heat at some point.

Posted by: horizontally-opposed Oct 16 2020, 09:28 AM

Still interested in this—and a cursory review of electric A/C (apparently without heat…) suggests old-school A/C is still far better.

Have also considered one heater box and one header for my 914 given my use and limited need for heat.

One thing I don't love about HEs is what Brad brought up in the first place: There's really no way to check the condition of the pipes unless you take the clamshells off...which is tough to do when they're welded on.

Posted by: 914ltd Oct 16 2020, 09:32 AM

The header pipes can be filled with water to check but that might not find the smallest cracks. Brad

Posted by: SirAndy Oct 16 2020, 09:40 AM

Webasto gas heater. Used to have one in my '74 Super Beetle way back in Germany. That thing turned the beetle into a sauna in minutes with sub zero outside temps.

Posted by: Mark Henry Oct 16 2020, 09:52 AM

Gas heater on the floor of the frunk you need a 3" tube welded into the gas tank so you can run the duct into the cab. A bit of creative ductwork to each corner and you can tie into the stock dash. The heater exhaust will require a pipe front to back and yes half dozen holes are needed to do the deed.
The diesel heaters will outperform SSI's,

If you look at the one factory 914/8, this is how it's done. There was a thread with a couple of fuzzy pics of the US owned 914/8 a year or so ago.

You can get the whole china copy kit of the espar diesel bunk heater for a couple hundred bucks, but would have to mount a small fuel tank (included). There's two copies, one is smaller than the other but more money, smaller might be easier to install.
Boat guys on YT tested them and say they're perfectly safe if installed correctly, but they couldn't get them to run right on gasoline, only on diesel (kerosene, heating oil, etc.)

Edit...doh...I bet I've already posted this info.

Posted by: horizontally-opposed Oct 16 2020, 10:00 AM

Gas heater, like HEs, is super effective and makes sense for a daily car—which is what 914s were once upon a time (and maybe still are for a very few?). Not sure I could bring myself to cut up my 914 to add a gas heater and its related components when HEs are readily available, lighter, simpler, and very effective. If I lived in a cold place, I'd definitely go with HEs over a gas heater.

My 914 doesn't get used daily anymore (last time was about 15 years ago, for a 12-month stretch), and thus doesn't need to be up to "real car" use standards. Honestly, all I probably "need" for heat is heated seats and defrost...and here in CA, the latter isn't a particularly tall ask. If a (very) little bit of heat could be redirected at my toes once the windshield is clear, well, that would be perfect.

Posted by: SirAndy Oct 16 2020, 10:11 AM

Why do you have to "cut up" the car for a gas heater? The units are small enough to fit under the rear trunk and you can duct the hot air straight into the stock inlets at the longs.
All you need is to run a larger fuel supply line through the center tunnel to accommodate for the heater needs.

I'm sure Chis could make a larger diameter version of his SS fuel lines for that purpose.

Posted by: horizontally-opposed Oct 16 2020, 10:35 AM

Hadn't thought about rear trunk…

(But I'd still probably do HEs before a gas heater.)

And still wondering about something like this. See a lot of mixed reviews, but one lead tied into the defrosters and one tied into the foot warmers might be enough to clear the glass and cut the chill—particularly in a 914 with heated seats.

https://alexnld.com/product/12v-24v-300w-car-truck-heater-warmer-dual-hole-heating-fan-window-defroster-demister/

Has anyone here tried something like this?

Edit: http://www.914world.com/bbs2/index.php?showtopic=244255

And the more you look at it, the more HEs look like the way to go even for minimal heat if weight and simplicity matter.


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Posted by: brcacti Oct 16 2020, 02:37 PM

Hello, so does that mean the electric heaters will slowly ruin your alternators? or just not heat the car much?

Posted by: Superhawk996 Oct 16 2020, 02:54 PM

Simple math. At 100% efficiency 55A stock alternator x 14v = 770 Watts of power. That assumes 100% efficiency, no wiring loss, and no fan to push the hot air. And that assumes your not running anyting else like an ignition.

For relative comparison maximum UL wattatge on an electric home heater @110v will be 1500 watts.

Sure there is a lot less space to heat in a 914 but after you deduct fan load, ignition loads, lighting loads, wiring losses, and some current to keep the battery topped up, there isn't much left to do heating with. Really only a couple hundred watts.

Long ago I tried to build a resitive heater for my 1st 914 (removed HE's for weight savings!) when I had to drive it in winter because I was broke and could no longer afford a "winter beater". My 1st year of college living in Northern Michigan and 1st year having to drive it in the snow. It was a pathetic failure. The math just doesn't work. I ended up driving around with a propane fed infrared heater and leaving the window craked to avoid CO issues. Much more effective. Not so safe. You never forget those days!

Posted by: euro911 Oct 16 2020, 05:23 PM

I have a 160 amp alternator kit that I purchased from Pete ( @http://www.914world.com/bbs2/index.php?showuser=3606 ) for the 914: http://www.914world.com/bbs2/index.php?showtopic=344493&hl=

... and I'll be upgrading the stock generator in the 912 to a high amperage alternator at some point.


A few points in my favor:

Both of those cars aren't considered daily drivers, so winter driving would be minimal at best.

Unlike some of you folks who reside in the mid-west and back east, I live in fairly mild climate regions, so heat would only be required during the coldest of dead-winter conditions, (which aren't really that bad). Again, winter driving of those vehicles would be minimal.

Even with the initial high current draw, thermostatic controls will more than likely keep the time element down to a minimum and reduce the load on the alternator(s). Once we're warmed up, the current draw would be minimized - to a degree (pun not intended).


I was curious to know what TESLAs utilize for heating the passenger compartments in those big, roomy sedans, so did a search. Apparently their early models were all electric, but newer models utilize a heat pump - so there's another idea to ponder ... https://www.currentautomotive.com/model-y-is-the-first-tesla-with-a-heat-pump-heres-why-thats-a-big-deal/#:~:text=The%20problem%20is%20that%20this,to%20power%20the%20car%20forward.

Posted by: Superhawk996 Oct 17 2020, 09:14 AM

Not to be a kill joy but that Orange wire running to the heat pump means high voltage.

EV's open up a whole new set of possibilities, but, it is by virtue of having around a hundred kWhr of high voltage battery capacity. Battery voltage is usually about 350 volts.

Posted by: 914ltd Nov 15 2021, 08:48 AM

2021 repost
Brad

Posted by: TX914 Nov 15 2021, 09:25 AM

Thank-you Brad @914ltd!

Posted by: windforfun Nov 15 2021, 05:53 PM

A magnet will stick if the metal has become magnetized over time or if it's ferromagnetic SS in the first place.