I need to do some investigation as to whether I need a new radiator, in which case I'll just replace both, or whether I have a fitting that failed. but I had a small puddle under the driver's side radiator today. It looks like the C4S radiators are about double the price of C2 or C4 radiators. Anybody know why that is? Will the regular ones work? I suspect they're a little larger because of the larger openings in the bumper cover, but I couldn't figure out the real difference after doing some research this afternoon. Thanks in advance!

 

I am in the same boat.
C4S rads are the same as the turbo, fairly pricey. I found the best price so far is from Rockauto. I have been looking also at CFS rads, it seems that both left and right are interchangeable, and are cheaper.

let me know if you find something cheaper,
cheers!

 

 

I think the CFS 3564 are for narrow body 996. it looks like 7055 is the wide body one

 

 

https://www.design911.com/Porsche-99...3274/prod3572/
Those were the cheapest I could find and I bought & installed them in my 2003 C4S a couple of weeks ago. They were a perfect fit and good quality. I hate to say it but you just missed a January deal with 15% off (which I was lucky enough to get).

This was the first time I had done it so I had some learning as I go that might help. If you are DIY, other than the pelican steps, here are some tips:
- If you think there is any rust in there at all, spend a bit more and replace the fans too ($100 each from rockauto). You have to take them out anyway so it's not any extra time. Mine looked pretty bad but I didn't have replacements when I did the exchange so had to put them back in.
- there are 3 hoses, 2 large & 1 small right at each radiator (supply, return, & breather). If I had it to do again I would probably replace those hoses & the clamps on them as well just for peace of mind (and I could've removed the previous ones without worrying about damaging them).
- It's easier to disconnect the hoses on the side connected to the wheel well and then take them off the radiator after it is out. To disconnect/reconnect the hoses at the wheel, the solid tubes the hoses can be pulled out of the clips at the wheel base to give you more room to work with.
- There are small washers to help connect to the bracket (#16 in this diagram: http://www.autoatlanta.com/porsche-parts/hardparts.php?dir=996-99-05&section=105-15). A couple of mine had nearly disintegrated and I spent like 2 hour driving around trying to find a near match. They are cheap and it won't hurt to have them handy. You need 6 for each side.
- The #17 clips in the diagram above are easy to remove so don't force them. You just have to lift the tab above the post and slide the clip out. You need to remove the one closest to the center of the car before you can remove the bracket with the radiator.

If you have any questions, I'll try to answer.

EDIT: Also, I was shocked at how bad the radiators looked at the lower back corners behind the AC condensers where crap just gets stuck and works into the radiator. I mean, they were so corroded and leaky I'm amazed I didn't have problems sooner. The connections between all the hoses were perfect. Unless someone has been disconnecting & reconnecting them a lot, I imagine it's more likely the radiators are leaking.

 

 

 

It's a c4s so, like the turbo, it's already got a center rad. I'm mistaken. That's only on some models.

 

 

I think it'd depend on how much you like to work on your car and/or if you mind going back in to replace hoses later. For people using a shop, I'd be in favor of "do it while you're in there" and replace the accessible hoses, since it would avoid duplicate labor costs. If you like to DIY, it isn't your primary vehicle, and you don't mind tearing it apart again if you get a hose failure, I wouldn't bother replacing them now (in your situation, with a leak).

If there was another reason for doing the work, like intermix, I'd be tempted to replace the hoses as preventative maintenance, but that isn't your situation.

One other tip - a vacuum coolant filling tool is almost a necessity on these cars to get a full fill without air being trapped. The UView Airlift or similar (I have a similar tool that works well enough, but if I did it over again, I'd have bought the UView).

 

Figured while I was in there I'd replace the supply and return hoses and fan seeing as they're 16 years old.
Bought the Schwaben coolant flush kit and had to remove the lid strut to fit it onto the reservoir.
Removing the frame that holds the rad and fan together was easy leaving the ac condenser hanging.
Check out Ashai's thread for a great step by step.

 

CFS is a good replacement, they arent very pricey and have more cooling due to design.

 

When I upgraded my 996.1 C2 with Turbo radiators, I bought the assemblies from Norspec Dismantling. https://norspecdismantling.com/ They are in Kent, WA. They are bigger...ask me how I know.

 

This is what FSI recommends and what I am doing on my 3.8 build.