I wasn't sure whether the ducktail spoiler on my car would be strong enough to fasten a higher lip, but I got it on. It can be adjusted for 2" higher, 6" total height or 3" higher, 7" high spoiler.

Seems very strong, although I'm going to put two more sets of fasteners in between so that I can go to stage two.

With a piece of 6061 cut 7" high I can go as high as 9". Pretty cheap modification as the aluminum is about $30 bucks.

Under all that blue painters tape is my painted spoiler.

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Mine is 10 inches tall....max for class. I fastened it 7 ways from breakfast to keep it from lifing/tearing off my semi-flimsy trunk lid. If you want any downforce (and we do) the whole works has to transfer it down to the rear tires....so it's gotta be strong to have any chance of being effective.

Curious why no one does a big front wing? Thats area that needs most downforce in AX. Buggy guys have started using big front wings.

Had fun beating them up in this past weekends AX with no wings.

It is actually stronger than it looks in the pictures. With two more rows of fastenes it will be better.

And if the rivet nuts don't stay put I have an alternative plan that will.

Wonder what the maximum downforce will be? I'm guessing <75lbs in any autox situation.

The underside is the next part of the project and as you said more challenging.

I could see the bottom side pulling out before the spoiler got ripped off.

I might have to strengthen the fiberglass stringers under the CF trunk.

If you can't stand on it, it's useless.

We just tested that on the new splitter for the 911. All of my 220 lbs and it didn't buckle.

Then we took it off after the first session as the 911 really doesn't need any more grip in the front. It was slowing us down.
Andy

Remeber track and AX speeds are much differnt. On AX you want a wing that would slow a car down on the track as you rarely get over 60 MPH. Its all about maximizing downforce in AX.

If Randal uses this car for Hillclimb he will want a front splitter as well that is capable of creating good downforce on front wheels. The dynamics of going uphill puts plenty of wieght on rear. I didnt have any issues with rear traction there - it was light front end that slowed things down.

But its important to remeber that most casual drivers like us guys cant put this limited amount of downforce to good use in AX.

I don't think this is a small splitter at all. it is 1/2" from the limit of XP rules.
at rest it rode 3 3/4" off the ground. at AX speed it is as you can see about 2"
at 120 MPH it clipped a crack in the road and I ran it over.

I have to admit your car is one of the few that I have seen that has a decent front spoiler for AX.

Splitter post severe cone damage.


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My 1st version was much stronger but smaller. I could punt a cone at 60 MPH and it would just go flying. Nothing went under the car. The one in the pic above was much bigger but the splitter bottom would flex and get all whacked out.
I think I have the design figured out now. and will make bigger better faster stronger yada yada.

I hand picked my spoiler at HPH to be bullet proof for AX. Mine was was amazingly tough. Designed by Rich B. Survived some major cone wacks and an off at the track.

Ack she was ugly compared to the new car. But I did retain tradition of the mal-fitting $250 front trunk lid. LOL!

You know if you were 6 feet closer to the cones you could be mch faster.
I didn't see a splitter or air dam. Let alone a taller spoiler.

Epic lose....

Niether of those cones where true apex cones based on features you cant see in the photos.

Boxster is in process. It will eventually get a splitter and wing of some kind, but damn! ...its rock solid at very high speeds compared to the 914. For a reletively stock car its fairly fast in AX and places in top 20 at 160 plus car events on road race tires. Its a sleeper for a stock powered 2480cc car.

What you bought from Rich I would call a valence.

Let him know. He called it a spoiler! LOL! Here is a better angle on the "valence". Guess if I put metal supports on it like yours then it would have been a splitter Joe still wins the splitter contest or is that called something else?

The splitter attaches to the bottom of the spoiler. It comes out 5" from the bumper when looking from above and extends under the front of the car all the way back to the steering rack cover. Which just happens to be the center line of the axle and by chance the limit of the rules. With my suspension travel I set it at 3 3/4" static.

Joe, On another topic. Have you seen some of the fast Mitsu EVO XP cars? Damn man those things have so much HP and they can get it all to the ground. I run against a national class EVO in XP here and I would have my work cut out in an XP 914. Boxster is a lost cause right now in XP. I need double the HP to even have a chance against the XP class EVO.

They make Randal's and JP's cars look like pussy cats on HP side. I'm sure those EVO's are cranking well over 400 HP. Acceleration they get is wicked.

Maybe you have not seen XP 63 It's a C5 Vette (sorta) pretty fast as well. I suspect the Black watch racing Lotus (sorta) will be the one to watch again with Fred Zust as the pilot.

Yup can't hold a candle or check book to any of those cars. It is what it is and I'm having a blast.

There is only so much HP that can be effectively put to the ground. the rest is just bragging rights. What is really important is acceleration curves which describes the whole car as a system.

HP + TQ + Grip = fast. as well as cornering grip to stay fast.

OK good test.

I've added enough bolts and riv nuts to hold more than 2xxlbs on the top spoiler.

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I started the bottom strengthening program:

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The washers will be tied to the fiberglass using JP's favorite epoxy.

Next I'll use sleeves to create a direct connection between the underside of the washers to the underside of the spoiler.

I've ordered some nice split open ended rivet nuts to be installed on the underside of the spoiler. They will spread the load much more than a washer can provide.

Next is figuring out how to utilize the down force energy. Now this part is complicated.

Joe,

You need to install a vertical piece to your "splinter" to trip the timing light. Unless the timing light is 2" off the ground, the leading edge of the splinter is going under the light before your front bumper trips the light. I've seen hillclimb cars add this.

That is a cool car. Now with a laser (timing light tripper) stick manipulator you could pick up time on a course, i.e., down at the start, up at the end .

Randal,

Don't think I haven't thought about it....

Sadly I don't think I have won or lost by that small amount.

OK, it's all done, except I think I will cut the ends into a half circle.

Fabrication isn't easy, even for simple things.

Here is a picture.

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A little angle on the end...mo better.

low height for track

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higher for autox

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side

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back

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Came out pretty stong. You will bend the aluminum before you break any of the fasteners.