I'm considering getting the carbon fibre hatch offered by rx7store.net. My only concern is whether or not I can use a gt style wing in conjunction with the lightweight hatch. Is the hatch strong enough to hold the high downforce created by a gt style wing, or do I have to stick to a more modest wing such as the '99 spec wing or the like? thanks...

 

you can use the gt type, but i would highly recommend reinforcing it. however, you may see some stress cracks around the mounting points. i have the cf hatch and am putting a gt wing on. we'll see how it holds up.

 

Damian, from the forum, has a c/f hatch and uses a GT type wing for his track car. You could always pm him for some more in depth info, but from what i know, the hatch holds up fine.

 

cool...thanks guys. Yeah I'll do some more digging.

 

Damian does have the big GT wing on his car (the one from rotaryextreme,) and there is a reinforcement plate imbetween the top and bottom of the hatch.

The wing stands have three mounting bolts, the front two of which are bolted through the stands, through the top layer of the hatch, and then through said mounting plate. The plate was custom cut about 10" by 4" or so, and the nuts/bolts holding the sandwich together are probably M6 size.

There's also a back bolt on the corner of the hatch that goes through the wing brackets, through the hatch, and then a fender washer and nut. He has a custom sized stopper that also is screwed onto the end of the bolt that hits the trim plastic when closed. He also has 'hood' pins holding the whole thing tight. This is partially to hold it solid, and partially to try to get a better seal and avoid water getting in. Water still can come in by the hood pins, at least for now. I think he said he might try doing something a little different there to stop that eventually.

With a (functional) wing, there's two forces you're generally concerned about. #1 is downforce, and that you want to make sure is transmitted as directly as possible to the chassis. #2 is drag; the main way the wing is going to fall off is to get ripped backward by drag. If you put a large reinforcement plate that contacts a large area of the hatch in front of the wing you end up distributing the drag moment over a large area so it will hold up well.

(I know all this detail because I just went out to my garage and looked at his car... )

 

Just a FYI, the wing he has is this one:

http://www.rotaryextreme.com/gtwing.htm

If you want I can take a couple pics of it and the mounting system tomorrow and post them.