So I am putting together my car and along the way I was able to buy this air dam rather cheap. Having very little seat time in a 914, especially in my own, I have no idea the advantages and disadantages of front mounted spoilers/ air dam.

What are the expected benefits or loses on using this or another style? Sorry to sound so FNG, but I figure there might be more people out there wondering too.

Here is mine (FYI only test fit and not properly mounted)
Click to view attachment

the theory of the air dam is that it will reduce the air pressure under the car, so that there will be less lift under the car at speed, so the car will in theory stick to the road better. front air dams can also be useful to supply ducted air to cool brakes oil coolers and radiators. The air dam effect is most at high speeds, at slow speeds the reduced under car pressure is negligable.

down side is they are low and can get banged up real bad if your not careful say as in hitting a parking curb, or clearing debries on a dirt road. (hence you wont see them on 4x4 trucks to often)

I would suspect it also effects cooling. The little rubber air deflectors just below the firewall are supposed to create some flow from above to bring air into the fan and thus the engine cooling tin. If you get rid of a good deal of this air flow... ???

Not really sure if this is true in reality. We cool with both oil and air so it could be compensated for with oil cooling.

You would have to test with CHT and Oil Temp before and after to know.

Less cooling air under the car is a downside.

it sits pretty low. you'll hate sidewalks and steep quick inclines in a hurry. looks like your about ready to roll. nice work.

k

It is. With a low air-dam, your engine temps will go up by a few degrees.

The real upside of a good air-dam is high-speed stability. Without a air-dam, a stock 914 gets really light in the back above 110mph or so. Enough to feel unsafe ...

Looks cool, but on the street it will not last long. I had a low air dam on my 70 back in 75 and replaced it about every 6 months from entryways and parking blocks or driveways. Wish those with the lower rubber lip were around back then.
Car is coming along, keep up the good work!
Tom

I will have to make a comparison on what it does to the Temp; mounted Vs stock

Anyone have their own data or experience on this?

I have a LE spoiler and what Andy said for my car 113 MPH is scary Loose

Looks Good Mark!!!!

I wont BS you that's Ugly , LE or Steel Valance

I would do your data collection with both CHT and Oil Temperature. I have noticed that my heads run cooler on the Raby 2432 but the oil is working harder. You might see one go up while the other goes down or both go up... As Andy has said, you will see some change. Engineers don't do things for nothing...

but to each his own...

I'd have to agree. Don't like the look of that valance. I like the LE valance with the little rubber addition on the bottom

I had a low car on the street once years ago
it didn't have a front cooler back then
I put a low 2 piece air dam on
the rubber skirt one like is currently being sold by a wonderful member vendor.


with the rubber nearly touching the ground I found that I could not keep the oil temp out of the red on a stock gauge on the highway...

I pulled the rubber and problem solved.

brant

All good advice. Having zero time with this car on the road and not even having the metal stock valence to compare...who knows what route I'll go.

PNW guys thanks for the brutal honesty!

I have a fairly low air dam on my car and it resulted in higher than normal oil temps. Cooling air ducted to an aux. oil cooler did the trick. Sinced I rarely drive above 110 mph it's mainly cosmetic. Anyway, I like it.

I thought you got a good metal valance? I still have one that is pretty nice

My solution for a dual-use car (which mine is not anymore at this point) is multiple airdams with dzus fasteners for easy swapping. I can use the LE type on the street or the others for track.


914 Front spoilers by cjcam, on Flickr

I've got a great front valence...just not presentable yet to mount up. I had this on hand. (Thanks NORD for the valence)

Great idea campbellcj! As my wife would say "It's like extra shoes and accessories for that special date."

If she said that, then thats the Rule...green light for options.



seriously though, thats a strange front spoiler , I have the one like elliots its great.

I have that same spoiler tucked away...
Ive never had it mounted but what makes it unusual is its all rubber!
no destruction from curbs it would just deflect.

Front Spoilers need to work with Rear Spoilers - one without the other can cause strange handling at high speeds.

A Couple of examples;
a 74 Porsche Carrera has a Rear Ducktail & no front spoiler, when the 75 Carrera came out it now had a WhaleTail, but also needed a Chin Spoiler to keep the nose on the ground.

962 RaceCars in the Mid 80's started adding a front wing, because in theory it needed more front downforce on Street Circuits. When they finally put it in a Wind Tunnel, Porsche found that the front wing disrupted air flow to the rear wing and actually gave them less downforce.

917s were one of worst handling Race Cars until they came up with a Rear Wing & front Dive Planes

YES! That is the best part....won't destruct like fiberglass or dent like metal.
I probably won't use it much. I've got some experimenting to do! Great info being provided.
Wife has been great. She even understands the needs for the different rims I need to keep buying and all the other items. She knows that she will get to drive it too!

Do the duck tail spoilers for the 914 actually work? I've been thinking of making a lexan rear spoiler because the back of my car does feel light above 100. I am currently running a snow plow front spoiler but am thinking of changing it.

With the OEM front valence, the steering would begin to feel too light from about 70-75 on up (not enough downforce on the nose). If you add some noticable crosswinds to those speeds (like crossing Kansas or Colorado), the steering gets spooky.

So, before the next trip (this was back in 1978), I added an LE front air dam. A very apparent improvement was effected. The car is more stable at extra-legal speeds and though stiff crosswinds can still be felt, the front end definitely feels more "planted"

I am partial to the LE piece because it is "period correct" , factory designed, provides a reasonable amount of curb and driveway clearance (if you're careful and your approach is slow), and looks appropriate to the car.

Paul

I have had the same feeling before the snowplow spoiler. Kinda scary.

With this set-up on my old car, the back-end wanted to lift off the ground above 115mph - I didn't have any type of rear spoiler

Click to view attachment

Yeah that's the spoiler I have and the tail definitely gets light over 100. Guess I'll have to look into a rear spoiler.

Woody, are you talking about mine or the Original Poster's?

If it's mine, doubt you have the same one, because I custom made that from a GT Lower Valance & an aftermarket valance - molded them together.

I've seen the Aftermarket one, but if just bolted on has a different angle than mine

I have a Sheridan rear spoiler going on my car for the above reasons. It's about 6" high and supposedly effective but not nearly like a wing. I do not want a wing at this point for aesthetic and classification reasons.

Yes buddy I was referring to yours. It looks similar, but yes mine is the aftermarket one.

Can you post pics? Can't find them on the Sheridan site.

This is it, it's called an SCCA legal Rear spoiler for $200 on his web page. I've heard nothing but good things about them.

Another important item to consider is frontal area (I don't think it has yest been mentioned on this thread.).

A spoiler like that would probably increase the frontal area, increasing the aerodynamic drag on the car. Now, it MAY improve the Cd a little by making the air flow better around the front of the car and reduce the underbody flow, but it is likely this spoiler would lower top speed and increase fuel consumption.

On a race car, that is often less important due to the significant power available, except stock classes, etc.