Rear Spoiler

[Martin]

I noticed on Chis Martinos latest build thread update that he has made a very nice rear spoiler. I like it a lot !
I have a couple of questions. Firstly, I will be building a gulf arched MDA and I've seen these spoilers on original gulf cars but with two additional holes corresponding with two holes in the rear body. Does anyone know what these holes were for and exacly where they should be located ? (I am guessing air ventilation for tire heat build up ?).
Secondly, does anyone have a dimensioned drawing of this spoiler that you would be willing to share.
Many thanks,
Martin

[Bill D]

Hi Martin
Those two additional holes were to allow more air to exit the rear clip. I made a spoiler very similar to the original you're speaking of by tracing the contour of the rear of the car on a piece of cardboard, then raising it two inches for where I wanted it.

I had a local machine shop mill the adjustment slots into the spoiler. It's made from .080 6061 T-6 aluminum

I've attached a couple of pictures I hope will help.

Cheers
Bill D

Original car (1076P)


First, I made a mockup with some heavy cardboard, cut to size and fitted. Next, I made a wooden jig from the template using some 3/4" thick particle board. I clamped my .080 aluminum sheet to the jig and cut the aluminum using a router and a flush cut bit. Here it is taped to the car to test fit.


Final product installed

[Martin]

Hi Bill,

That's an incredible car you have there. I've just taken a look at your build threads. If I can get even halfway close to your level of detail and finish I will be very happy indeed.

Many thanks for the spoiler pictures. I now know how and where to start.
Cheers,
Martin

[Chris Martino]

Hey Martin,

I can trace my finished spoiler on heavy paper if you want a template. Bill e-mailed me info before I sent mine out to the machine shop, same type of material etc. You could add the additional holes to it anytime.

Let me know-

Cheers!

Chris

[Larry]

Chris,
Is it possible to get a copy of that spoiler tracing?
Larry

[Chris Martino]

Hi Larry,

Sure, no problem. Anyone else? I did take the time to get it looking & fitting correct so you shouldn't have to modify it. This spoiler is only good for the rear body style that has the license plate recess.

You pay for shipping and I'll do the rest.

Let me know-

Cheers


Chris

[speed220mph]

About the rear spoilers, I talked with John Horsman about them. First, they didn't use them for looks . . . they do look nice and purposeful, though. The obvious purpose was for rear downforce at low speeds, or under about 120 mph and less. Notice that #1075 and other Gulf cars didn't use them at LeMans because of excessive drag and front-end lift at high speeds, such as down the Mulsane straight. Front-end lift had always been a problem until the new front body work was installed. Vanes were installed on the front corners for helping with this situation, but John said repairing them was too much of a pain they were removed. On the street, consider them excessive weight and not much benefit except for looks. Again, a spoiler looks nice.

[Martin]

Thanks for the info,
I'm only really looking at the rear spoiler for asthetic street appeal rather than actual track benefit, but your post brings up a good point. Are the replica cars that we are building, especially MDA's, as this is posted in the MDA forum, built from moulds of a car that has this new improved front end bodywork ?
If we were to go flying down the Mulsanne straight, would we notice excessive front end lift ?

[Chris Martino]

When you refer to vanes are these the same as the canards and spats fitted to the front wheel arch area? I have seen several original GT's with the rear spoiler added so I assume they must work on certain tracks.

My spoiler weighs in at 875 grams so I don't think it will make much difference.


Chris

[speed220mph]

Chris: These are the vanes mounted at each front corner to provie additional aero downforce. John told me that the little additional downforce they provided wasn't worth it compared to the additionial repair work that was required to keep them straight. Minor paint swapping resulted in these things getting bent, which also reduced or eliminated any benefit from them. But just like additional drag from the rear spoiler when it was extended to give downforce, the vanes increased drag. This parasitic drag and the weight--they would do just about anything to reduce weight as long as it didn't reduce performance--was considered sacrificial.

[David Morton]

And Mercedes tried the canards at Le Mans (fitted just before the start in consultation with Newey).
Mercedes Benz CLR 1999 Le Mans flip - Google Video

[FRPGUY]

Hey Chris, please email me at; datonabill at msn dot com
I tried emailing you, but it bounced back