Better Cooling

[kieselba3]

Hi guys,

Just bought a 2000 C4 about 2 months again and love it.

I do have an idea that I haven’t seen covered on the board yet. Has anyone thought of putting holes or louvers in the front wheel well covers to improve airflow over the radiators? I thought of this because I use to have two turbo cars that put the intercooler in the same location as the 996 radiators. One of those cars had louvers to help with air flow. The other didn’t have louvers but pretty much everyone drilled out the cover to help air flow. Would the 996 benefit from a modified wheel well cover?

[714dre]

Interesting idea... but there must be a reason if Porsche engineers haven't done it..

You do know about the 3rd Radiator kit, right? It is at the top of the 996 DIY Mods section.

[kieselba3]

I have read about that kit as well. This would just be free way to maybe add a little better cooling.

[therock88]

Here is what the wheel well of a 997 Twin Turbo looks like. Has the radiators in the same spot, so maybe Porsche decided there was some merit to your idea?? Do not see what it would hurt to add some holes to it??

Good luck....

DC

Edited April 6, 2010 by therock88

[Loren]

As I recall the GT2 has even larger openings in the wheel well cover - who wants to pay over $200 for each wheel well cover (partial) to try it out?

[therock88]

To Clarify...

Unless I misunderstood....The original poster was asking about potentially putting (drilling) additional holes in the wheel wells for more airflow...

Thus my comment "Do not see what it would hurt to add some holes to it??". My point is/was that other P cars do in fact have vent holes (as indicated in the photo), so it would likely not hurt anything.

Not sure who was/is recommending buying new wheel wells? Although that would be another more expensive option, if someone chooses to do it and if they fit.

DC

[judgejon]

turbo and C4S has vented wheel wells.... DIY would seem possible for others....

[Wicked 996]

I did this myself on an older VW turbo when the inter cooler was tucked in there. Just cut long slits with a dremel and give each an 1" cut up on the edge"

looks likes this: |_______|

Then use a heat gun to heat up the plastic to make it pliable - then push the louvers you made out and when it cools they will stay where you put them.

Sorry I dont have pics and I sold the VW :)

[carsareart]

Wicked 996,

that is a neat idea to put louvers in the fender wells . I might just have to look at my car. So far I have been fine in the temp dept., last summer I cleaned and combed my radiators and condensers. I also run water wetter. (it might be snake oil but it does not seem to hurt.)

[ALLSPEED]

The vents make a lot of sense.

[1schoir]

I did this myself on an older VW turbo when the inter cooler was tucked in there. Just cut long slits with a dremel and give each an 1" cut up on the edge"

looks likes this: |_______|

Then use a heat gun to heat up the plastic to make it pliable - then push the louvers you made out and when it cools they will stay where you put them.

Sorry I dont have pics and I sold the VW :)

Nice solution. Would look (and probably function) much better than just drilling holes IMO.

Regards, Maurice.

[bmohr]

great brainstorm! I think i might have a go at this. Thanks for sharing.

[kieselba3]

That was my original idea, vents. I did that to my VW and it did work very well. All you need is a heat gun and a sharp utility knife. I might try it this weekend. I'll post pics once i get it done.

[Wicked 996]

just be sure on the louver lengths to not interfere with the tire at sharp turn angles - measure how close your ties get at full lock to not make the louvers too long!

[therock88]

That was my original idea, vents. I did that to my VW and it did work very well. All you need is a heat gun and a sharp utility knife. I might try it this weekend. I'll post pics once i get it done.

Might want to heat it and bend the slots IN so you do not change the clearance for the wheel....

DC

[ALLSPEED]

Do we have any new input on this? After looking at my real engine temps on my HVAC controls I see a need to increase my cooling. I'm planing on a third radiator but am stymied as to the air flow through the existing radiators on my 99 996 C2. Looking at diagrams I have I can't see a clear path for the hot air to escape like the ones with vented wheel liners. Am I missing something? Guy's out there with knowledge of the air flow please help. How does this hot air escape? I left myself open with that last remark.

Edited April 10, 2010 by ALLSPEED

[RFM]

The hot air escapes, with the help of the little front spoilers (in front of the wheels) which create vacuum, through the hole under and behind the radiators, just in front of the spoilers. The mod as mentioned above will not get rid of your problem.

[ALLSPEED]

Thanks for an answer RFM. If these little panels or spoilers create a vacuum to help exhaust the hot air then would adding vents or holes disrupt this? Not having other manuals than my 996 do the models that have venting in the wheel well exclude these bottom holes or they completely different? How many 996's have you seen with those little spoilers dangling from one end? I have one on order myself. Sounds like they are more important than I realized. After reading many threads on many sites it seems that 996's naturally run a little warm. I don't believe I have a cooling problem but facing my first 110 degree summer with this car in Central California I don't want to be caught with my pants down. If I understand the theory the key factors that I'm looking at are surface area(third radiator) and air flow for heat exchange. I plan on adding a third radiator for peace of mind as this makes sense to me. The other is air flow and I was interested if anyone had any input on that. I don't feel like butchering my wheel wells but wanted to know if there were updated Porsche or DIY alternatives and if they help and how much. Thanks again, Robert.

[RFM]

Creating supplementary air vents in the plastic wheel well does any harm to the air flow, but as said it does not help much. A third radiator and/or a lower degree thermostat are also limited help and under certain circumstances, if you've followed the discussion in an other topic on this forum, you will establish that both, the pro and contras, for a piece being right and not. If you make the comparison with other European cars, Porsche use the same temperature thermostat, the cooling system contains twice the quantity on cooling water (more than 20 litre) and use the double on cooling surface area (radiator area). The real trouble is, IMHO, by design, pump, engine, at certain RPM's, the limited water flow.

[phillipj]

RFM,

On my 06 997 I notice that the temp stays steady in all conditions. Unlike my previous 996 cars where the temp fluctuated quite a bit. Do the 997 cars have an improved cooling system? Is the water pump more efficient?

Thanks!

[RFM]

Indeed the last M engine series (MY06) have had a small adjustment pump/engine inside water channels, concerning amelioration of water flow, but unfortunately, by limitation of the available opportunities of the specific design, not far enough, the result on slow traffic and at idle (low RPM) would be even better.

[phillipj]

Indeed the last M engine series (MY06) have had a small adjustment pump/engine inside water channels, concerning amelioration of water flow, but unfortunately, by limitation of the available opportunities of the specific design, not far enough, the result on slow traffic and at idle (low RPM) would be even better.

Thanks!

[flyingpenguin]

Thanks for an answer RFM. If these little panels or spoilers create a vacuum to help exhaust the hot air then would adding vents or holes disrupt this? Not having other manuals than my 996 do the models that have venting in the wheel well exclude these bottom holes or they completely different? How many 996's have you seen with those little spoilers dangling from one end? I have one on order myself. Sounds like they are more important than I realized. After reading many threads on many sites it seems that 996's naturally run a little warm. I don't believe I have a cooling problem but facing my first 110 degree summer with this car in Central California I don't want to be caught with my pants down. If I understand the theory the key factors that I'm looking at are surface area(third radiator) and air flow for heat exchange. I plan on adding a third radiator for peace of mind as this makes sense to me. The other is air flow and I was interested if anyone had any input on that. I don't feel like butchering my wheel wells but wanted to know if there were updated Porsche or DIY alternatives and if they help and how much. Thanks again, Robert.

I have the 3rd radiator installed on my 2000 C2, and even so in stop & go traffic in Houston , TX I see coolant temps around 100 C with ambient around 80 F (25 C).

Increased airflow is the only solution and what works quite well is to engage the A/C and not pull a lot of cold air from it (inside the car) by running the fan at max two notches. There is also a stage 2 fan mod out there, but this works just as well because it throws your radiator fans into high gear.

JP