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Posted by: ss6 Jun 27 2003, 08:53 AM

FYI -

Was paging thru a recent Pegasus catalog looking for new toys when I spotted some inline blowers for not too much money. Might be good for heater or heater booster app's. Lower right hand corner of the page:

http://www.pegasusautoracing.com/pdfs/017.pdf

OK, its a non-issue at the moment, but those of us with 4-season climates and anemic heater blowers know the issue. Some 911's use booster blowers mounted in the footwells to get better heat, these look a little easier to adapt since they're in-line. They look small enough to go either in the footwell or behind the gas tank. I believe our heater hoses are 2.5" ID, so their 3" model would be the closest. Gonna buy one to experiment with, I'll let all y'all know how it goes.

Anyone know of similar stuff?

Posted by: James Adams Jun 27 2003, 09:20 AM

I can't get the pdf to open for some reason, but here they are at a boat place for $16.21.

http://www.allaboutfishing.com/Store/products/productDisplay.asp?manufacturer=ATTWOOD&model=TURBO+3000+IN%2DLINE+BILGE+BLOWER


Attached image(s)

Posted by: Demick Jun 27 2003, 09:23 AM

Personally, I think using any sort of booster downstream of the heat exchangers is a bad idea. As originally designed, the heating system is pressurized, meaning that the air is blown into the system. This means that if there are any holes in the heating system (heat exchanger sheetmetal, connections, flapper valves, etc), that the pressurized air will leak out at these locations which is a very good thing.

Anytime you put an air mover or booster downstream of the heat exchangers, you are now trying to suck the air through the heating system. This means that if there are any holes in the heating system (which there always are), you will be sucking air in through them. Depending on where these holes are located, you can end up sucking exhaust gases, carbon monoxide, etc into the heating system and pumping it directly into the passenger area. This is a very bad idea!!

To make matters worse, people who usually add these kinds of items are usually trying to compensate for a heating system already in bad shape (flapper valves not working properly, heat exchangers rusted out and falling apart). So these are now sucking air through a heating system full of holes.

If your heater isn't working well, then fix it the right way. Stainless heat exchangers are not that expensive when you consider your cheap alternative may be giving you a healthy dose of carbon monoxide. My 914 heater works so well, that on a really cold day, I might have the heater lever pulled up only about 10%. More than that and I bake (of course, it doesn't really ever get cold here by most people's standards).

Sorry ss6, I'm not trying to be harsh on you, I just want people to be safe.

Demick
'74 2.0

Posted by: James Adams Jun 27 2003, 09:28 AM

That's a good point Demick. I never had a problem with the heat in a 914 with everything hooked up and working right. My VW on the other hand...

Posted by: tat2dphreak Jun 27 2003, 09:47 AM

who needs heat in TX?!!! it's hot at midnight in december!

Posted by: James Adams Jun 27 2003, 09:56 AM

It wasn't all that hot during the ice storm in January...

Posted by: campbellcj Jun 27 2003, 11:31 AM

I'm actually working on a similar project, but for cooling. I'm going to rig up a scoop/inlet in the cowl grille with two, 3" hoses and inline blowers to direct a pretty decent quantity of air onto the driver & passenger. The main use will be when sitting on the grid at the track -- fully suited up -- in summer heat. That's miserable.

For cold weather, I rigged up little sheet alum blocking plate that will block off the cowl intake.

Since the temps at Willow Springs swing from about 30F in the winter mornings to 110F in the summer/fall afternoons, it makes race car ventilation interesting.

Posted by: Curvie Roadlover Jun 27 2003, 11:53 AM

Posted by: john rogers Jun 27 2003, 01:02 PM

I have a pair of those in our 1974 stock 914 hooked to a three-speed switch and they are great, especially if you need to defrost the windshield in a hurry. The only drawback is a little noisy, but the whole car is pretty noisy!!!!

Posted by: Curvie Roadlover Jun 27 2003, 01:23 PM

Posted by: campbellcj Jun 27 2003, 10:59 PM

Posted by: ss6 Jun 28 2003, 07:38 AM

Thanks for the warning on the CO, guys, it's a really good point. My heating system is not quite stock, I've got those $#@%^ B&B stainless headers "with heat", meaning somebody hacked up a few squares of stainless to "enclose" a few inches of header. Waste of good sheet metal. Despite the fan from the six, boosted by the stock blower motor, I only get a trickle of heat in the cabin. All I want is to thaw the friggin windshield on the way up to LimeRock in March and November.

One minor retort, though - the '84 Carrera I cannibalized for my engine swap used footwell booster blowers in the heating "circuit". (Snagged them too, but they are a funky right-angle design and tough to shoehorn into the teener.) I agree that ya gotta keep the heat ducting up to snuff, but boosters don't necessarily mean negative pressure at the flappers.

Posted by: ss6 Jul 2 2003, 02:29 PM

FYI -
The blower I mentioned last week showed up today, airflow is OK, but not as good as the 911 mini-squirrel cages. It is the same as the one pictured in James Adam's post above, and the vendor in his post is about $10 cheaper!

Always though Pegasus was a little pricey...