More cooling questions.

I have read through the cooling system threads and I still have a couple of questions. My car has the TPC big radiator kit with cooling fans, the A/C kit with condenser, and a Mazda RX7 oil cooler stacked together. The oil cooler is located at the lower portion of the radiator. The car has a Turbo nose and I have the undertrays in place. I have read that airflow needs to be directed through the radiator and nowhere else.

I want to improve the air flow through the radiator and I want to know if it would be best to put the plastic duct back in that originally went to the intercooler. I would extend the duct so it goes all the way to the radiator.

I have also read that the original Porsche fans are better than the TPC fans. I have an original Porsche fan setup and I am curious of what is the best way to attach them to the TPC radiator. Should I remove the phillips screws that attach the TPC shroud to the radiator and remove the entire fan and shroud or should I trim most of the TPC shroud away and use it to mount the original Porsche fans to it?
Thanks in advance, Gil

Do you have the vented turbo header panel? If so, you can seal the top of it's opening to the top of the radiator. That helps airflow a lot. I usually try to seal the sides of the radiator to the front bumper opening with some abs sheeting. This insures that no air flows around the condenser and radiator.

As far as fans go, I only use the stock fans. I will cut out the TPC fan shroud just enough for the fans to be wide open and still have a flange of the TPC shroud to bolt the fans to. This has made every single 944 LS i've built not overheat. Every car I built using the TPC fans or some other brand fans, had heating problems. Even Renegades radiator and fan kit overheated on one 944 a customer recently bought, until I put the stock fans on.

I have a turbo header panel but I'm not sure if it is vented or not. There are no external holes in the front of it if that is what you mean. There are a lot of areas for leakage of airflow at the top of the radiator the way it is installed now. That's why I thought that installing the duct for the stock intercooler and extending it back to the radiator would help funnel air to the radiator at the top.

Is there a preferred location to put the OEM fans on the TPC radiator? Should you locate them more towards the top or bottom of the radiator? Or will they only fit in one location?

I was referring to the aftermarket header panel that has the hole for the intercooler. Sorry, I wasn't real clear on that. There is a plastic panel you can get from Porsche that clips on to the stock radiator, but it can be attached to the body as well. This helps seal the open areas above the radiator.

I center the stocks fans from top to bottom on the TPC shroud. I cut out as much of the shroud as possible while leaving just enough for the fans to bolt to.

I have all of the original plastic pieces from the stock setup. I will see if I can fit some of them back in. Some of the hoses for the oil cooler, remote oil filter, and power steering cooler might be in the way but I can work around them. I'm sure after I channel more air directly through the radiator, the car will run much cooler. I didn't realize how bad my current setup was until I looked at it closely. I thought the big radiator would take care of everything. Thanks for the help, Gil

putting vents in hood helps to get the hot air out of engine bay and overall increases effecincy of the cooling systym .The engine bay is very tight on 944 and helping get the hot air out really helps . A good altenator that is 250 amps or more will limit voltage drop to fans . I use 2  spal fans on mine . If fans arnt getting full voltage that will limit the the fans  ability to cool .Ive also made vent cutouts in header panel . Also stacking your radiator and condesor to close to each other can limit cooling to .You need a couple inch separation between them

Good point on voltage drop to the fans. I have a decent alternator but I remember that the wiring going to and from the resistors for the fans looked like it had been overheated. Repair of the wiring was put on the "to do" list and I have not done it yet. I will address the wiring this winter.

I plan on installing some louvers in the hood too. Does anyone have a good vendor that has a large assortment of louvers to pick from? I'm looking for a louver that is 6" by 24" to go at the forward center portion of the hood above the throttle body. This will allow me to cut out the outward dent that I put in the hood by not grinding the throttle body enough (yes, I am an idiot).

I agree voltage drop was issue I had but solved it with good wiring connection and a high amp altenator . I thought about louvers and fabbed up some grills instead . Ive been working on mine several years and its trial and error . Ive felt like an idiot a few times myself but I worked through it .Hahaha But you never know til you try .Its also cheaper than paying someone else .

gwistrup, you have the RX7 oil cooler below the rad? I use that same cooler but placed it above the rad where the intercooler goes and setup the factory intercooler ducting to feed the oil cooler. Even without a vented header panel the oil temps are solid.

Water temps were harder to manage. For a radiator I have the big Wizard all-aluminum one with all the factory ducting, factory fans and a belly pan. Sill, I did have to vent the hood to get sufficient cooling to run the car hard at the track. No a/c.

Rich

I am working through some track day cooling issues
One thing that made a difference was hood louvers from
Al at Race Louvers .
I have a big wizard rad , spal 16 inch fan , I ducted the nose to the rad . I just moved the oil cooler about 4 inches forward of the rad so that it doesn't restrict air flow. Will let you know how it works in the spring.

I have a 944 LS1 conversion and had heating problems until I made the following changes.
1, Remove all the blockage in the nose that keeps air from flowing straight through to the radiator. 944s were designed so all the air flows underneath the car and then gets sucked up through the radiator by the fans. There is no air flow through the radiator from the front of the car.
2, I cut additional (2 inch by 8 inch air flow holes through the front bumper with screens for protection.
3. I used the after market vented header panel.
4. I vented the hood to alleviate heat soak and improve heat removal and air flow. Big improvement.
5. Get rid of the plastic overflow tank and use an aluminum tank. The plastic tank only allows using a 15 psi radiator cap which allows water system to heat and steam. Aluminum tank increases the allowable tank pressure to 25 psi.

My car can now run with the A/C on in 90 degree heat at 100 mph and stays under 200 degrees. Normal running temp is around 185. On a cool day fans run intermittently and engine runs right at 180 degrees.

I would appreciate it if you could post some pictures of what you have done for the location of your ducting and hood vent style and location. I'm curious how each of you tackled the problem. Thanks, Gil

Here are the photos of listed cooling improvements.
https://1drv.ms/u/s!AsCfwL-4G_4alWKTMF5QAVuKnDcM?e=JVWUXk

As mentioned, stock fans and shroud work best.

I made a secondary radiator that is located exactly where the intercooler was, using the intercooler ducting too. I have a small SPAL fan wired in with the main fans on its own relay.. Don't have any pictures, but I did discuss this on here, some time ago.

Porvette, thank you for the pictures. Where did you get the louvers? Did you locate them to reduce heat from the exhaust as well as to extract heat from under the hood? If I located a vent closer to the front of the hood, would it be as effective?

948, What type of radiator did you use in the intercooler space? Where did you get it?
Thanks for the help, Gil

gwistrup948, What type of radiator did you use in the intercooler space? Where did you get it? wrote:Thanks for the help, Gil  

Custom made to fit, had a friend weld it up.

The first version was made from a pair of E350 rear heater cores.
D5UZ18476D

In the end, the heater cores and custom made version worked the same.

I was in the process of installing the OEM fans in my conversion this weekend and I realized that if I used a flat mounting surface instead of trimming the TPC fan mount I could gain 3/4" clearance to the front of the engine. I purchased a 1 1/2" by 6' piece of 1/8" thick aluminum and cut into 3 pieces. I welded two pieces together to put on top and I used the single 1 1/2" piece on the bottom. The stock radiator has provisons to mount the fans directly onto it so I figured I could do the same with the TPC radiator. The fans do not need to be trimmed to clear the engine with this installation.