Radiator and fan questions

About to start an LS swap of my 1991 944S2. I've already purchased the engine, its an LS 5.7 from a 2004 Corvette.

The S2 currently runs (anyone want to buy my engine ?) and has a less than 3 year old new OE Porsche radiator. I also currently own a Ron Davis radiator from Renegade of unknown age that appears to be in excellent shape.

I live in a hot climate.

Any opinions on using the stock S2 radiator, using the Renegade/Davis radiator, or going with a custom radiator?

I've owned the S2 for many years and one thing that has always greatly annoyed me is how loud the dual cooling fans on the radiator are. I don't know if this is everyone's experience, but mine sound like a jet engine (can hear them inside the car).

What are my options for a quieter but still efficient radiator fan cooling system if I stay with the stock radiator or Renegade/Davis radiator?

The OE Porsche radiator probably won't work very well if you live where it is hot. You will be better off with the Ron Davis radiator if it is similar to the radiator used in the cooling kit that Texas Performance Concepts sells. The TPC radiator is physically larger and I think it is called a "Dual pass" radiator.

Most importantly, you must retain all of the original plastic ducting and seals because they really help direct the air into the radiator. You also will be MUCH better off if you retain the OEM fan assembly with the new radiator. It sounds like a jet because it works very well at pulling air through the radiator. None of the aftermarket options out there will work as well as the OEM fan.

I originally put a TPC large capacity radiator in my car using the aftermarket fan that came with the kit. It did not run very cool so I put the stock Porsche fan back in per suggestions from this forum. It was better but it would still get hot when driven hard. I finally reinstalled all of the ducts and plastic parts between the bumper and radiator. Now the car cools off when driving down the road. If the gage is in the middle when driving in stop and go traffic, it will cool off to the 1/4 mark after you reach 30 MPH. I thought the big radiator was good enough. It wasn't. You need proper air flow too.

Sent you a PM

I never could keep mine cool especially on the track. Street driving was fine though. Since I built it for a track car I quickly sold it. What a money pit

mr965 wrote:I never could keep mine cool especially on the track. Street driving was fine though. Since I built it for a track car I quickly sold it. What a money pit

Understand about the money pit angle. I've built a few restomods over the years and have been into 944's a long time, so I'm familiar. What radiator did you run? Any thoughts on what you could have done better or differently?

Thanks, this is valuable info. Much appreciated.

gwistrup wrote:The OE Porsche radiator probably won't work very well if you live where it is hot.  You will be better off with the Ron Davis radiator if it is similar to the radiator used in the cooling kit that Texas Performance Concepts sells.  The TPC radiator is physically larger and I think it is called a "Dual pass" radiator.

Most importantly, you must retain all of the original plastic ducting and seals because they really help direct the air into the radiator.  You also will be MUCH better off if you retain the OEM fan assembly with the new radiator.  It sounds like a jet because it works very well at pulling air through the radiator.  None of the aftermarket options out there will work as well as the OEM fan.  

I originally put a TPC large capacity radiator in my car using the aftermarket fan that came with the kit.  It did not run very cool so I put the stock Porsche fan back in per suggestions from this forum.  It was better but it would still get hot when driven hard.  I finally reinstalled all of the ducts and plastic parts between the bumper and radiator.  Now the car cools off when driving down the road.  If the gage is in the middle when driving in stop and go traffic, it will cool off to the 1/4 mark after you reach 30 MPH.  I thought the big radiator was good enough. It wasn't.  You need proper air flow too.