924Board.org

kpasko · Joined: 25 Jun 2013 Posts: 35 Location: California

Hey all, so I've had various overheating issues for some time now. '78 924NA, with factory AC that never worked and so has been removed (but dual fan shroud is in there).

Fingers crossed that electrical housekeeping and a system flush will take care of it, but I'm starting to consider just exchanging some cash for peace of mind. From Ideola's great post on all-things-upgrade, I got fairly sold on a Ron Davis rad and some version of better fans. That said, since I have the dual-fan setup, would it be worth it at all to reuse the current shroud? should i get rid of it entirely and mount some new low profile ones directly to the rad? Pros/cons of various setups?

Any advice/tips would be great.

Also, I'd like to avoid a pick 'n pull/used rad, hence the Ron Davis choice above). However, there are ~$400 new ones available for the 951 and 931...

http://www.autohausaz.com/pn/94410603103
http://www.autohausaz.com/pn/95110603150

if anyone would strongly recommend saving the ~$200 over the Ron Davis and just going with one of those I'd be open to it, although all of the hose splicing that I believe is required seems to me a bit more trouble than its worth

thanks toofer sages,
K

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

I bought an aftermarket rad from Automotion, and it was garbage. Could not keep the car cool, had some sort of flow problem.

With Davis rad, stock setup will bolt up, but I went for this setup for higher CFM, less weight, and lower current draw:

Bam, thexthy!
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

kpasko · Joined: 25 Jun 2013 Posts: 35 Location: California

very thexthy indeed! pair of 10" spals?

daniel · Joined: 18 Jun 2009 Posts: 686 Location: Sydney, Australia

I use a standard radiator with my race car and have even whacked an oil cooler in front of it, no temp problems at all.
_________________
Over the top of skyline, total brake failure.... hit the wall at over 200 kp/h at the dipper, so anyone who has to brake for the esses is a pussy.
1977.5 Race Car, CAMS Group S Spec
1989 944 Cabriolet

kpasko · Joined: 25 Jun 2013 Posts: 35 Location: California

Will probably upgrade the fans either way, and ideally I can fix any issues with flushing, electrical, etc. tuneups to the rest of the system and just run the stock rad as you mention. Am just anticipating the event that it is the radiator itself that needs fixing (it is a '78 after all, and it sat for a good long while before I got it...)

has anyone recored one of these guys?

leadfoot · Posted: Mon Jan 19, 2015 10:56 am Post subject:

there are really simple things you can try before spending on a new rad...

clean the grounds around the fan circuit

rewire the fans to run the directly off a relay from the battery and not through the ceramic resistor

replace both the thermostat and thermo switch for the correct or lower temp units...

change the crossover pipe configuration for a larger diameter and run it through the larger port of the rear coolant flange to give better supply to no 4 cylinder.

flush your coolant system

add an oil cooler
Stu
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

Carrera RSR · Joined: 08 Jan 2010 Posts: 2312 Location: Somerset, UK

To shroud or not to shroud, that is the question!!

I decided not to shroud the up rated all ally 944 rad and install a more efficient open slimline fan. The thinking that the air flow through the rad when the fan is not triggered but the vehicle is moving would be more beneficial/efficient. When the fan is triggered in stop start traffic it takes no time to drop the coolant temperature. Also once moving again it takes no time to bring temps back in line.

I do need to upgrade the oil cooler next which will certainly improve engine temps further
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1980 931 - forged pistons, Piper cam, K27/26 3257 6.10 hybrid turbo, 951 FMIC, custom intake, Mittelmotor dizzy & cam pulley, H&S exhaust, GAZ Gold, Fuch'ed, Quaife
Now www.924board.org/viewtopic.php?t=34690
Then www.924board.org/viewtopic.php?t=31252

kpasko · Joined: 25 Jun 2013 Posts: 35 Location: California

hrm...all this talk of oil coolers has me thinking...

http://www.lindseyracing.com/LR/Porsche/944RADBIL/951-RAD-BILOIL.html

How much of a hassle is converting the hoses from the 944T setup to 924NA?

fiat22turbo · Joined: 18 Jan 2006 Posts: 4040 Location: Portland, OR

You'd be better off just buying a generic aftermarket oil cooler and plumbing it in using a Ford Small Block oil filter adapter (bolts right up).

The Lindsey one is great, but unless you're already running a 2.5L Turbo and its radiator and front end you'd have to modify it to fit your car anyway.
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Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)

kpasko · Joined: 25 Jun 2013 Posts: 35 Location: California

i see, that makes sense; thanks for the tip. Probably makes sense to do separate from the radiator anyway such that I can stage my upgrades/changes anyhow. Current itinerary-

1a) maintenance/troubleshooting/upgrade electrical + hoses (have already taken care of thermostat/temp switch); sys flush, debug.

2) Fan upgrade- Spal, Mizu, American Eagle, other??

2b) Debug pt 2. At this point, should definitely know whether the radiator itself is problematic. if so, I think Ron Davis rad upgrade seems like path of least resistance, although spendy. Convince me otherwise?

3) Consider adding aftermarket oil cooler, other mods

4) Dakar rally