Bill, in a way you are right but the rear hatch window vents on the F40 were not just there simply because the engine was rear installer to allow heat out (look at the size of the window)?.

Part of the problem of using a Perspex type rear windows is the light weight design and the fact that it's not OEM installed.

Most race cars require venting into the cabin to allow excess heat to escape. In most conditions vents are added into the side windows but this does not allow for the air to escape hence a buildup of pressure resulting in the rear window being blown out in extreme circumstances.

To alleviate this problem the rear of a car needs to be vented (air outlet) so that the pressure in the cabin remains the same as outside not taking into account wind resistance (negative force).

This is why most dedicated race cars of our type have to use braces to help protect against this problem in the event of the rear window blowing out.

By venting the rear allows air that comes in to the cabin out and also any pressure out (negative effect) - It is simply a case of calculating volume + pressure against area and mass.

This is not just a problem with track cars ... When TVR launched the Cerbera, due to the large side windows there were, and still are many reports of the rear window blowing out. This is a problem which never got resolved at the factory.

Because our rear Porsche screens are so large the problem is escalated hence the current brace solution.

 

Guns that's a great question.

The windows can be mounted simply by pushing them up inside the current cars guide frames and then blocked off at the bottom with a plate or if you want to use them with your existing motors/winders then I recommend removing the inside lower window rubber seal and also the lower outside seal and fitting a universal 'U' shaped capping plastic seal and then you have full up/down operation.

This is not the case with any other current product out there as others are not convex to the exact shape OEM window shape.

They can be supplied without the slide window as well. I'm just showing this as an alternative dedicated race setup development.

Sorry if that wasn't extremely self descriptive but I'm sure you get the picture.

 

Future, thanks for the description. I'm looking for a flush fit attaching the slider window to a welded in frame around the window to create a flush profile due to the high speed nature of the car.

If you can, shoot me a PM with cost for those windows (sliders) as i'm sure my shop could configure them for what I'm doing.

 

Gun's ... I am not doing this as a 'cash cow' exercise mate - it's simply to put back into our Porsche community what we all get out mate.

Our cars seem to be somewhat forgotten today yet they represent some of the best in automotive history regarding front engine, rear wheel drive layout … It’s just a shame that Porsche don’t take a note from Ferrari who have now realized the front engine, rear drive is the best platform but there’s 911 heritage for you (Got to love the controversy though even if it does not make any sense)!

It just amazes me that a simple solution has not been adopted before and Porsche should have done this when developing their race cars but I guess technology was not then what it is today (same goes for budget). – So this is our way as a community to continue evolution and current technology back into our passion. I only wish there were more of us doing development but it is a limited market that’s why all us owners should be there to contribute and nobody does a better job than John D for his exceptional work with this forum.

But at last … Porsche are working on the Panorama – Here’s me hoping they do a two seat version to rival the 997

 

PM sent

 

Amen Brother, that's why I'm doing my GTR project - trying to do what Porsche did with the 911 GT1 on the 951 platform. Get some recognition back to the 951 game and show the Porsche community that a 951 in the right hands can become a supercar.

 

I'm fully with you on that one ... I hate the fact that we get looked at as the peasants in the Porsche community - Well that is how it is in the UK!

Turn up to a show over hear with a mod’ed car and you get treated like a boy racer – Some people don’t understand and that’s why I love Rennlist as we all do – Each to their own.

I only wish I had more time to contribute but that will come shortly as I’m working on a lot of 911 stuff as well to be launched soon.

Something for everyone and all that s41t

 

Did you paint in black the area where the glass meets the frame ?

TIA

 

Future, I realise these products are mainly intended for race applications, but are they also suitable for a mainly street car? I can understand security would be compromised but are there any other reasons that would make these products unsuitable for he street (apart from the rear hatch popping off at speed that is!!)?

Do these products suffer from the clouding that the usual Lexan hatch suffers?

By the way, whereabouts in Cheshire are you? I'm from Cheshire (south Manchester). Have you got a showroom or are you a 'garden shed' organisation?

 

sweet stuff, im subribing to the thread beats the **** out o thoose bend it yourself things. any weight figures?

 

I am going to be in for a set, maybe 2 sets.
Can you fire me a PM with costings.

Cheers
Tom

 

Yeah, good stuff...
I am interested and will follow this thread, too.

 

subscribing

 

Ok I have been made busy today



This is the first photoshop draft.

Lets get some feedback and I'll then fully explain the design and why it is as it is etc

 

Sorry … Just to answer some previous Qu’s:

marcoturbo - Yes paint was used so that it looks as factory as possible which I hope the pics illustrate.

Sawood12 – Firstly the Lexan is stronger than glass hence an actual increase in security. And yes they are intended for both trace/race and street with the emphasis on quality to look as OEM as possible. I’m based in Wilmslow, Cheshire so we will have to catch up soon mate.

Anders44 – Love the comment mate, this was the intention.

Hi Tom – Good to hear from you again mate. I will send you a PM but we do not have the actual costs confirm at the moment. Will have this info for early next week ... promise