924Board.org

Horizonblue · Posted: Sun Apr 28, 2013 7:31 am Post subject: 924 Rear diffuser

Some time ago, I purchased this one on ebay, and now it's time to mount it on the car.

I thought it was a bolt on and go (paint in between), so I was dissapointed to see that it didn't fit. I mean, it is very bad, it's like my car is one inch longer than the car this came from.

I have seen them on a few of the last 924s. This one I have here, is not original, it's made from fibreglass.

But it fits so bad that there must be some other thing wrong, than just a bad copy.

Is the bodywork a bit different in the back of the early 924, compared to the last 924?
_________________
Euro 924, 1976

"If you can't fix it, don't break it"

/P.G. Andersen

BionicBalls · Joined: 05 Jan 2009 Posts: 642 Location: Charlotte, NC

That is a diffuser from a 944 Turbo. It has a different bumper setup.
_________________
1980 924 NA
1982 931

Horizonblue · Posted: Sun Apr 28, 2013 5:57 pm Post subject:

leadfoot · Posted: Sun Apr 28, 2013 6:57 pm Post subject:

definately not from a 944 turbo,
you've got one like this below... the key difference is where the edge starts behind the rear arch. as you can see below the valance butts up against the wheel well, the 944 turbo version starts behind the arch contour in about 2 inches. The styles are also different as the 44 version is level whereas you version curves up towards the rear hatch.
Stu
http://www.google.com.au/imgres?imgurl=http://www.porsche-foorum.org/album/albums/userpics/10026/valge2.jpg&imgrefurl=http://forums.rennlist.com/rennforums/924-931-944-951-968-forum/677971-1979-porsche-924-5speed-1000-allentown.html&h=600&w=800&sz=183&tbnid=Qg1PJw4bG6kZmM:&tbnh=97&tbnw=129&prev=/search%3Fq%3D924%2Brear%2Bvalance%26tbm%3Disch%26tbo%3Du&zoom=1&q=924+rear+valance&usg=__2VM1wJhEjPEIj0ei29YD4sLLzEw=&docid=6JWRxcJ3Y1DZdM&sa=X&ei=zON8Ub-qF-m1iQeY5YGYDQ&ved=0CHUQ9QEwCg&dur=2157
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

Horizonblue · Posted: Mon Apr 29, 2013 6:05 am Post subject:

Seen here, everything looks ok.

But here is the problem.

If the car was 1 inch shorter, the protrusion (with the circle around) would slip up between the bumper and the bodywork, which I believe it is meant to. The arrow is pointing at a hole in the diffuser, which can't be used for anything, since there is a gap there, created by the protrusion.

The other part of the diffuser (for the right side) is completely impossible to mount.

Any suggestions?
_________________
Euro 924, 1976

"If you can't fix it, don't break it"

/P.G. Andersen

leadfoot · Posted: Tue Apr 30, 2013 7:14 pm Post subject:

Your mounting angle looks wrong, you can see thst it tilts up towards the edge of ths rubber on the bumper. So far as mounting it next to the muffler you might need to fab up some mounts. Pretty surf an 80/81 has a point where this would be able to be mounted, not sure about earlier designs jad a different heat shield in the rear.
Stu
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

Raceboy · Joined: 01 Mar 2004 Posts: 2327 Location: Estonia, Europe

I have the same diffuser (though original part, made by BBS) on my white 924:

The part that you have is correct shape, but the heat shield may be not original perhaps? You have to drill a hole for the bolt and it would bolt right up.

The diffuser, side skirts and front valance were optional on late 924 S'es, it was supposed to be standard equipment on 924's what were meant to be 924 S2 (narrow body with late oval dash, late windscreen etc).

My Gulf racer was one of the prototypes of that kind, unfortunately the PO did not know this and just saw it as a good platform for a racer and bought it for that from Germany.
Few years ago there was also one of those for sale in mobile24 for 22 000 euros, had all the paperwork which proved that the car belonged to Porsche until early 90'es. ~20 or so were made.
_________________
'83 924 2.6 16v Turbo, 470hp
'67 911 2.4S hotrod
'90 944 S2 Cabriolet
'78 924 Carrera GT replica
'84 928 S, sold
'91 944 S2, sold
'82 924S/931 "Gulf", sold

'84 924, turbocharged, sold.
http://www.facebook.com/vemsporsche

Horizonblue · Posted: Wed May 01, 2013 5:40 am Post subject:

Raceboy, that diffuser on your car looks great.

It's a strange problem.

On the pictures, you will see that mine is held in place by a small jack. I have placed the diffuser, so it follows the wheel arch and the side of the car quite ok. If I move it, so the protrusion slips in between the bumper and the bodywork, it fits like crap anywhere else.

I guess there is nothing else to do, than cut it into pieces and glue/fiberglass/fill/sand it together again, with the loose parts attached to the car. I have actually already started, by cutting the right part into two pieces. As it was, it could never fit the car. I might as well just have bolted a toilet seat under the bumper....
_________________
Euro 924, 1976

"If you can't fix it, don't break it"

/P.G. Andersen

Raceboy · Joined: 01 Mar 2004 Posts: 2327 Location: Estonia, Europe

Whoa, just wait a second on this! I can take photos of mine tomorrow, how it fits, my guess is that you are cutting a wrong thing and it really should be the heat shield, not the valance.
_________________
'83 924 2.6 16v Turbo, 470hp
'67 911 2.4S hotrod
'90 944 S2 Cabriolet
'78 924 Carrera GT replica
'84 928 S, sold
'91 944 S2, sold
'82 924S/931 "Gulf", sold

'84 924, turbocharged, sold.
http://www.facebook.com/vemsporsche

Horizonblue · Posted: Wed May 01, 2013 3:12 pm Post subject:

A few pictures would be great, I will wait a bit, before I cut it into more pieces

_________________
Euro 924, 1976

"If you can't fix it, don't break it"

/P.G. Andersen

edredas · Joined: 09 Dec 2004 Posts: 861 Location: Charlotte, NC

Here's what it looks like underneath a 924S. It is similar, if not identical to the 951, and the holes for the diffuser are already there.

Horizonblue · Posted: Mon May 06, 2013 2:00 am Post subject:

Thanks for the picture, here is how my car looks like, from approx. the same angle.

The difference, whatever it might be, is not really obvious. But like I said, it's like my car is one inch too long. The right side of the diffuser, was impossible to mount. It's like the spare wheel well sits too far back.....

Oh, on the picture you can actually see the right part of the diffuser which I have now cut into two pieces

I'm afraid that's the only way to go, cut it into pieces, mount it on the car, and fiberglass it together again.
_________________
Euro 924, 1976

"If you can't fix it, don't break it"

/P.G. Andersen

Raceboy · Joined: 01 Mar 2004 Posts: 2327 Location: Estonia, Europe

I took the photo of the rear of my 1983 924 NA, will upload it after work.

I wouldn't cut it apart, but rather would modify the sheet metal.

edredas, where is the information coming from regarding number of prototypes built? I have been into 924's for ~15 years and kept an eye on them in mobile.de on regular basis and also in forums but until this moment only seen two such prototypes: one is mine and other is the one I mentioned eariler.
_________________
'83 924 2.6 16v Turbo, 470hp
'67 911 2.4S hotrod
'90 944 S2 Cabriolet
'78 924 Carrera GT replica
'84 928 S, sold
'91 944 S2, sold
'82 924S/931 "Gulf", sold

'84 924, turbocharged, sold.
http://www.facebook.com/vemsporsche

edredas · Joined: 09 Dec 2004 Posts: 861 Location: Charlotte, NC

Horizonblue, I measured roughly 108mm between these two points. I know it's of no use now, but I'm curious to see if your car is longer?

Raceboy, the number I gave was just an estimate. It isn't clear how many were built, but there were quite a few batches made. I don't want to clutter up his thread with off-topic pictures, so sometime later today I might start a thread in 924S discussions.
_________________
'84 944 -White, Brown interior
'84 944 -Red, Automatic
'86 944 -Garnet, Fully loaded, Koni suspension
'87 924S -Red, 300hp 951 swap
'87 924S -Red, Project Car
'88 924S -Red, Daily Driver

Horizonblue · Posted: Wed May 08, 2013 6:03 am Post subject:

Edredas:

I have approx. the same dimension between the two points, maybe a few mm more.

That is if you are pointing at the point I think you are. If I measure the total length of the sheet metal here, I have 150 mm.
_________________
Euro 924, 1976

"If you can't fix it, don't break it"

/P.G. Andersen