New wing possibility for the Holbert 928 racer.
07-05-2006, 08:31 PM
#16
Drifting
Mark,
You might want to take the uprights all the way through the body and weld a piece to the frame rail. I got this idea from Tom Falkenberg, and it would provide a lot more strength for the wing. The hatch will flex a good bit with the way you have it mounted. My setup will have two pieces welded to the frame rails inside of the fenders that will come up through the body right beside the rear quarter windows, then the wing will be removable from outside of the body if I want to have different sized uprights.
You might want to take the uprights all the way through the body and weld a piece to the frame rail. I got this idea from Tom Falkenberg, and it would provide a lot more strength for the wing. The hatch will flex a good bit with the way you have it mounted. My setup will have two pieces welded to the frame rails inside of the fenders that will come up through the body right beside the rear quarter windows, then the wing will be removable from outside of the body if I want to have different sized uprights.
07-05-2006, 10:56 PM
#17
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Seems you have a lot of great thoughts on your new project! One thing I would think about is the longer the uprights the more prone they will be to flex from side to side. I've studied the GT3 cup car wings and Porsche keeps the uprights on the stubby side and the wing is below the roof line a bit. I'm sure you have access to a cup car to examine the height and how it attaches to the car. The wing is mounted to the rear engine hatch and works quite well as does Mark A.'s wing that resembles the cup car wing. I believe his wing mounts to the hatch too. And no one says you have to mount the wing at the very bottom of the hatch. Possibly a point a little further up on the hatch would do well. Maybe look at the GT3 profile and try to match it.
The big thing with this wing is it's adjustability which will really help fine tune your handling. A lot better than your current wing although from your last race results it did not seem to hurt you too much!
Good luck with it,
Constantine
The big thing with this wing is it's adjustability which will really help fine tune your handling. A lot better than your current wing although from your last race results it did not seem to hurt you too much!
Good luck with it,
Constantine
07-09-2006, 03:54 AM
#18
Rennlist Member
Thread Starter
So here is the almost final install.
The wing works amazingly well. what a differnce in downforce compared to the "tilted" stock GTS wing.
If any of you remember, the GTS wing was tilted 10 degrees. it put down 80lbs of downforce at 120mph. This new GT3 cup wing puts down this at near 80mph and near 130lbs of downforce at 100mph
I tested it by leaving the rear hatch ajar, and used a pointer to determine compression to the hatch spring at the differenent speeds. at 100mph , its maxed out, but it actually locked the rear hatch , which i have to usually slam or lean on with alll my weight to engage. anyway, here is the new wing with the endplates. weight of the wing is the same as the fiberglass GTS wing.
The GT3 wing is carbon fiber and weighs 6lbs. (however the end plates are 2lbs for both, so i will have to look for some sheet fiberglass to replace them with)
the picture below shows 130lbs of weights on the rear wing with a chair seat, the old GTS wing to spread the force. it is solid as a rock, no flexing side to side either. only 2 bolts per side holding it to the steel rear hatch.
Mk
The wing works amazingly well. what a differnce in downforce compared to the "tilted" stock GTS wing.
If any of you remember, the GTS wing was tilted 10 degrees. it put down 80lbs of downforce at 120mph. This new GT3 cup wing puts down this at near 80mph and near 130lbs of downforce at 100mph
I tested it by leaving the rear hatch ajar, and used a pointer to determine compression to the hatch spring at the differenent speeds. at 100mph , its maxed out, but it actually locked the rear hatch , which i have to usually slam or lean on with alll my weight to engage. anyway, here is the new wing with the endplates. weight of the wing is the same as the fiberglass GTS wing.
The GT3 wing is carbon fiber and weighs 6lbs. (however the end plates are 2lbs for both, so i will have to look for some sheet fiberglass to replace them with)
the picture below shows 130lbs of weights on the rear wing with a chair seat, the old GTS wing to spread the force. it is solid as a rock, no flexing side to side either. only 2 bolts per side holding it to the steel rear hatch.
Mk
Originally Posted by Constantine
Seems you have a lot of great thoughts on your new project! One thing I would think about is the longer the uprights the more prone they will be to flex from side to side. I've studied the GT3 cup car wings and Porsche keeps the uprights on the stubby side and the wing is below the roof line a bit. I'm sure you have access to a cup car to examine the height and how it attaches to the car. The wing is mounted to the rear engine hatch and works quite well as does Mark A.'s wing that resembles the cup car wing. I believe his wing mounts to the hatch too. And no one says you have to mount the wing at the very bottom of the hatch. Possibly a point a little further up on the hatch would do well. Maybe look at the GT3 profile and try to match it.
The big thing with this wing is it's adjustability which will really help fine tune your handling. A lot better than your current wing although from your last race results it did not seem to hurt you too much!
Good luck with it,
Constantine
The big thing with this wing is it's adjustability which will really help fine tune your handling. A lot better than your current wing although from your last race results it did not seem to hurt you too much!
Good luck with it,
Constantine
Last edited by mark kibort; 07-15-2009 at 06:19 PM.
07-09-2006, 11:42 AM
#19
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Nice!!
Mark,
Nice job on the install! Interesting way to test the downforce too. Can't wait to hear how it feels on the track. You did what I've been wanting to do for some time using a GT3 style wing on the 928. Now all it needs is some color to tie it into the car. Any plans on the color scheme?
Constantine
Nice job on the install! Interesting way to test the downforce too. Can't wait to hear how it feels on the track. You did what I've been wanting to do for some time using a GT3 style wing on the 928. Now all it needs is some color to tie it into the car. Any plans on the color scheme?
Constantine
07-09-2006, 11:53 AM
#20
MK,
I watched the video last night.... time to beat that M3 and EVO outright huh...
You guys all have cast iron ***** just for going door to door like that...
Do you know a guy named Adrian Tang who also has an evo... local... involved with SCCA... he is a good friend
Wing looks good for a race car... looks like it will be effective
good luck
LO
I watched the video last night.... time to beat that M3 and EVO outright huh...
You guys all have cast iron ***** just for going door to door like that...
Do you know a guy named Adrian Tang who also has an evo... local... involved with SCCA... he is a good friend
Wing looks good for a race car... looks like it will be effective
good luck
LO
07-09-2006, 01:45 PM
#22
Rennlist Member
Thread Starter
Thanks!
I was pretty happy with the brackets and the stability. kind of spooky putting 130lbs of weight on that kind of structure, but its very strong! its set at 7.4 degrees now, but if you look at the air flow off the roof, it may have a real angle of attack of near 15 degrees. for a track like road america, ill have to find a way to flatten out the wing!
color will probably be red for the wing, and then black for the brackets.
mk
I was pretty happy with the brackets and the stability. kind of spooky putting 130lbs of weight on that kind of structure, but its very strong! its set at 7.4 degrees now, but if you look at the air flow off the roof, it may have a real angle of attack of near 15 degrees. for a track like road america, ill have to find a way to flatten out the wing!
color will probably be red for the wing, and then black for the brackets.
mk
Originally Posted by Constantine
Mark,
Nice job on the install! Interesting way to test the downforce too. Can't wait to hear how it feels on the track. You did what I've been wanting to do for some time using a GT3 style wing on the 928. Now all it needs is some color to tie it into the car. Any plans on the color scheme?
Constantine
Nice job on the install! Interesting way to test the downforce too. Can't wait to hear how it feels on the track. You did what I've been wanting to do for some time using a GT3 style wing on the 928. Now all it needs is some color to tie it into the car. Any plans on the color scheme?
Constantine
