924Board.org

bruce76-924 · Joined: 22 Feb 2007 Posts: 105 Location: Bradford, England

Dan,

Just to put a slightley different angle on the cooling system, I run the standard pump with the bypass pipe and lower thermostat return pipe blocked off, this pushes water through the block and then out of pipe fitted instead of the rear core plug at the rear of the block. The water is then run through a second radiator and back out to a large diameter pipe ( like Steve's car ) to the back of the cylinder head, then finally exiting through the thermostat housing and back into the the first radiator.

I used to run it with 2 water pumps just to make it more complicated but I've just removed the second pump to try and simplify things a bit and the engine ran very cool when driving so I'll see what it's like with just the 1 pump.

Bruce.
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1976 924 LHD, full cage, semi tube chassis, 951 brakes, lightweight 951 body panels.
1.8t engine conversion with Holset turbo and 6 speed Audi gearbox.

bass gt · Posted: Tue May 20, 2008 6:06 am Post subject:

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

Snagged a Wizard Cooling 951 Alu racing rad over the weekend:

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erstwhile owner of just about every 924 variant ever made

Raceboy · Joined: 01 Mar 2004 Posts: 2327 Location: Estonia, Europe

Dan, I read you're going to delete heater. Did you consider some alternative against sweating windscreen on humid days?

I'm in the dilemma right now as I made 30mm pipe from back of the head to water pump but I'm not sure if I should plumb a heater core also to it.

As I'm not aware of the heated windscreens for our cars (and it's cost would be sick high), I'm wondering what is Steves solution to this considering he races in foggy England

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'83 924 2.6 16v Turbo, 470hp
'67 911 2.4S hotrod
'90 944 S2 Cabriolet
'78 924 Carrera GT replica
'84 928 S, sold
'91 944 S2, sold
'82 924S/931 "Gulf", sold

'84 924, turbocharged, sold.
http://www.facebook.com/vemsporsche

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

Peep, it's a good question...in my case, I was planning to just setup a blower in the cockpit (maybe one of the late 944 style centrifugal blowers as they produce good CFM) along with some ducting. Since my car will be a warm season only, I don't think it'll be necessary to have a heater core, only to have airflow moving over the interior of the windscreen. I may be mistaken, but I think that Vaughan has eliminated the heater core on his race car, and since we're in the same locale, I figured it would probably be suitable for me too.
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erstwhile owner of just about every 924 variant ever made

Raceboy · Joined: 01 Mar 2004 Posts: 2327 Location: Estonia, Europe

Ok, I hope Steve will chime in also regarding this.
Though I'm tending towards keeping the heater core and just letting all of the coolant from the back of the head flow through this and just use the fan when needed.
I weighed those stuff also (heater core together with early style plastic system and fan) and they weigh som 3 kg's which is not too much. Oh, forgot additional coolant, about 1 kg of that also.

But I think it's gonna stay.
_________________
'83 924 2.6 16v Turbo, 470hp
'67 911 2.4S hotrod
'90 944 S2 Cabriolet
'78 924 Carrera GT replica
'84 928 S, sold
'91 944 S2, sold
'82 924S/931 "Gulf", sold

'84 924, turbocharged, sold.
http://www.facebook.com/vemsporsche

leadfoot · Posted: Sun Dec 21, 2008 6:02 pm Post subject:

I can just see it now... $$$$ racing car with this stuck to the dash...
http://www.outdoorgb.com/p/caframo_ceramic_demister_18106/

FYI for humidity control, air con is more effective than heating.

I bought a water solenoid valve that I never got around to installing.
Something like this... available in bore sizes up to 50mm. You can essentially create your own heater box and run the flow through the solenoid off temperature control etc from the ECU...
Working temp is to 80C but it would have a safety factor built into it.

http://cgi.ebay.com.au/solenoid-valve-solenoid-valves-water-solenoid-valve_W0QQitemZ190274250163QQcmdZViewItemQQptZLH_DefaultDomain_15?hash=item190274250163&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A1|39%3A1|240%3A1318
Stu
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1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

I've been doing a bit more digging on the electric water pump setup, and this Jabsco pump looks like it might be an upgraded alternative to the Davies Craig unit in just about every facet, including lifespan (3500 vs 1500 hrs), flow (29 vs 22 GPM), and cost (<$200 vs $270).
Jabsco 50840-0024 Cyclone Circulation Pump

Pump Body: Stainless Steel
Port Size: 3/4" pipe threads. Available with NPT or BPS threads.
Flow: 110 Litres/min (29.7 gallons/min)
Pressure: up to 0.6 bar (8.7psi)
Impeller: Stainless Steel Anti-clog impeller design
Shaft Seal: Mechanical
Motor: Continuously rated, Motor life 3500 hours. ISO 8846 MARINE and USCG Regulations for Ignition Protection • ISO 8849 MARINE Bilge Pump Standard.

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erstwhile owner of just about every 924 variant ever made

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

For engine coolant? I have the predecessor to this pump for my IC, and I don't believe it is suitable for two reasons. First, the flow rate listed in the specs is without resistance. Once you start pushing coolant through the engine and rad, the flow drops considerably (i.e., running it out of a bucket, it shot water over the house, but running it through my IC core and heat exchanger turns the flow into a fast trickle).

Also, they don't like 200 degree water (ask me how I know).
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

Ahh. Hmm.
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erstwhile owner of just about every 924 variant ever made

bass gt · Posted: Wed Jan 14, 2009 12:54 am Post subject:

Guy's,

My strategy for controlling the misting of the screen is nothing more ellaborate than wiping the inside with Rainex!! Same stuff you use on motorcycle helmets to stop the visor fogging. Remember that my car is used for short runs.
However, if i need to address this further, i will just fit an electric heater unit, such as those truckers use to heat their cabs. I can fit it anywhere, which is nice for the weight distribution, and just run an air hose/pipe to the screen. I really don't want to be diverting engine coolant into the passenger comartment and then having a heat exhanger and associated equipment. Just to much for my application.
Alternatively, why not modify the 911 concept and put an air chamber around the centre area of the exhaust, run a tube from it and a variable speed fan? Then you have warm air without the hassle of running coolant pipes into and out of the car.

Steve
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Front Wheel Drive is the Devil's work.

simsport · Joined: 06 Nov 2002 Posts: 573 Location: UK Warrington

Steve
Remember your last season when it rained a lot!.........well rather than buy rainex I used washing up liquid on the inside of the screen and it lasted for ages. The trick seems to be to smooth it on thinly and leave it to dry for as long as possible. If you lightly polish it off the thin residue is clear but works great.....guess you have done this being a biker....my visor always used snot to keep it clear!

Cheers
Simon
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Blown is always best!

Martijnus · Joined: 29 Dec 2006 Posts: 2019 Location: Netherlands

Steve, you should be really sure that the exhaust isn't leaking

however, the citroën 2cv had a similar setup for interior heating.
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"Rule: Turbo's make torque, and torque makes fun." (C. Bell)

924 "50-jahre", 1981.
MSII/extra, LPG, ITB's, 5lug.
To be turbo'ed in a while.
Killed her at the Nurburgring, Porscheless at the moment

pocketscience · Posted: Wed Jan 14, 2009 10:17 am Post subject: Re: Screen

RC · Joined: 25 Mar 2007 Posts: 2637 Location: Australia

Being a scuba diver I can assure you that the best recommended way to prevent the glass on your mask fogging up is to spit (saliva only

) on the inside, rub it around, then a quick rinse.

Might get a dry mouth after doing a windscreen.