911 engine temps and factory looking solutions

[nzaldivar]

Hey Folks,

I have a 79 911SC that runs about 200-220F depending on outside temperatures. For instance, last night it was about 205F with temperatures in the upper 80'sF. Not sure about track temps, it has been about 2 years since I have been to the track for DE events

I have a mocal fender cooler with a fan that comes on around 180 (external probe stuck in cooler)

I have noticed since adding a front lip spoiler the temps are higher. I removed a metal scope on the bottom because it seemed to be blocking air, which lowered the temps alittle.

I have also added the side scoop, which seems to work well in traffic, but not at speed.

Any how, would adding a hole in the front skirt and scooping the air toward the fan the only solution that works?

Is there a cleaner more factory looking approach?
Cooler in the front, looks good, not really factory?

The goal is to have temps below 200F, always. (is this too ambitious)

ned

[Paulporsche]

Ned,

Try a search. There was a recent thread on this. People were trying holes and/or scoops in the valance, fog lamp, headlight, side marker light, turn signal, etc.

[Chuck Moreland]

At 220 you really don't have much of a problem. 190-210 is ideal.

But if you are seeing 220 on the street, you can bet your track temps will be substantially higher.

You have numerous options.

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Make sure you have enough cooler.

Some of the commonly available mocal "kits" for 911s have very small coolers, they are focused on low price instead of cooling effectiveness. Their 50 row is about the biggest cooler you can stuff into the fender. If you have something smaller, you should replace it with a bigger cooler.

I always recommend putting in the largest cooler you can fit into you physical location. The couple hundred dollars saved installing a small cooler is a false economy that undermines the whole purpose.

The biggest / best cooler for the 911 fender is the factory Carrera type. It is larger than the mocal 50 row, fits the fender perfectly, allows use of factory brackets / hoses/ stone guard and keeps your car original. Money well spent.

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The cooler is only as good as the air supply. Make sure you are ducting the air properly.

You need to have a means for getting air into the fender.

The factory made a notch in the bumper that you can't see unless you crawl under and look up. This is a minimum requirement.

You can also cut holes in the valence (though it doesn't look stock) or remove the fog light if you have thru-valance foglights.

You can cut out the back of the headlight bucket and pull the headlight when you are on the track. This "scoop" is good for about 10 degrees.

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Make sure the air coming into the fender is going through the cooler.

The factory carrera stone guard is sealed to the inner wheel well, forcing air through the cooler not around it. The mocal "kits" omit this so much (most) of the air goes around the cooler not through it.

Seal the area under horns between the cooler and valence. This will box in the cooler and prevent air from escaping beneath it. Use aluminum or rigid plastic sheet.
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Add a second cooler in the driver fender or under the bumper.

This is a more involved and expensive installation and requires new body work/ fabrication/ hoses / etc. But if you need max cooling this is it.

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Replace the hard lines under you door with Finned Oil Lines. These are a plug in replacement that keep the stock look, but have about 4X the cooling surface area of the stock lines. This is good for about 15-20 degrees.

[JonT]

Wow Chuck--that is a fantastic writeup--bookmark this one. Thanks