CF rear diffuser

[zachf88]

Ok guys, there have been many threads started on this. PPi design is planning on making one for the hefty price of $3000 USD. This is just an outrageous price. The only carbon fibre rear diffuser I've seen was Red_Rocket's, but he sold his car WITH the splitter on it (even though I would have paid him 750 quid or so for it!). So how can we get a carbon fibre rear diffuser manufactured for the RS4 that will not cost over 1000 quid?

*just as a note, the rear diffuser on the RS4 is one piece with the bumper. What would be needed is a "cover" that goes over the original diffuser (like Red_Rockets)

[tartan_rob]

IMO you would need to cut out the central section and then fit one in - if you wanted it for looks and performance. If just for looks, you could slip over the top.

The cost again depends on who doing, how much time spent and whether it is pure asthetic or actually assisting airflow under the car.

If someone can get me a diffuser that damn near fits, I'll make a mould and produce something in either dry lay-up or pre-preg.

[P_G]

If you are brave you could try this....

http://www.carbonmods.co.uk/Products/Ca ... SK300.aspx

You can get the rear diffuser section separate as a part, so I might try this and see how I get on with this skinning kit. Like said, this is only from a looks perspective.

Rob, what happened with your oil cooler splitter? Were you now trying to get someon to market it for you as I'd still be interested in one?

[poon]

If you are brave you could try this....

http://www.carbonmods.co.uk/Products/Ca ... SK300.aspx

You can get the rear diffuser section separate as a part, so I might try this and see how I get on with this skinning kit. Like said, this is only from a looks perspective.

Rob, what happened with your oil cooler splitter? Were you now trying to get someon to market it for you as I'd still be interested in one?

oooh, just watched the video where he does the wing mirrors, looks good and not too difficult, they also do various Ford and Subaru bits, wonder if they would be interested in bits for the RS4 if we got a big enough order?

[P_G]

I watched the video too, looks like you just need time and a lot of patience. And maybe a couple of spare parts to practice on. I will probably stick (no pun intentded) to a company doing more fiddly bits for me.

[tartan_rob]

P_G I have the splitter on the car (RS4) and now one on the RS6 as well....it was too expensive to make for a sensible price. The layup time was extensive and the materials not much better. I think the cost would be prohibitive. Having said that I have done a few bits for the '6 and the '4 now and have propshaft's in testing along with driveshafts waiting to go....

As for CF production, it is not rocket science at all, but it does take time and if it were easy, wouldn't everyone be doing it...? The materials have to be laid up in the right direction otherwise there is little strength. And of course, if you are doing for the performance benefit, really you need to use pre-preg, which involves a serious autoclave and vac pumps and the expense etc goes up exponentially. Skimming is great for the look but in reality it is not that easy - trust me....or try it yourself...

[poon]

I fancy wing mirrors, rear diffuser, front oil cooler diffuser and seat backs

[tartan_rob]

If there is enough interest in the oil cooler splitter for either '4 or '6 then I'll have another look as I have a few other molding options open to me now.

[P_G]

P_G I have the splitter on the car (RS4) and now one on the RS6 as well....it was too expensive to make for a sensible price. The layup time was extensive and the materials not much better. I think the cost would be prohibitive. Having said that I have done a few bits for the '6 and the '4 now and have propshaft's in testing along with driveshafts waiting to go....

As for CF production, it is not rocket science at all, but it does take time and if it were easy, wouldn't everyone be doing it...? The materials have to be laid up in the right direction otherwise there is little strength. And of course, if you are doing for the performance benefit, really you need to use pre-preg, which involves a serious autoclave and vac pumps and the expense etc goes up exponentially. Skimming is great for the look but in reality it is not that easy - trust me....or try it yourself...

Thanks Rob,

I realise it is not easy and I'm not suggesting wathcing a video is going to make me an expert, but for aesthetics purposes it is worth me having a go.
Do you have any spares of the RS4 oil cooler splitter? PM me the cost if you would make one from new.

[tartan_rob]

It is worth having a go. I was trying to convey (badly) that if people get less than perfect results, not to be dis-heartened. It is hard to get right and even harder to perfect.

[Gecko]

OK guys I'm prepared to have a serious look at manufacturing CF parts for our cars but I want some accurate feedback on quantities, just how far to go with the design and to outline some concerns I have.

The wish list seems to be:
- Rear diffuser
- Front Splitter
- Airbox
- Wing Mirrors
- Seat Backs

OVERALL
While I live in Australia, I own 5x manufacturing factories in China and already have all the necessary resources to manufacture these parts. I haven’t done accurate costings on these parts but since the labour cost will be much lower, I’d expect to be able to offer much more realistic pricing than what’s out there.

The basic process would be:
1) Get 1x of each standard Audi part to be replaced.
2) Scan each Audi part using a 3D scanner to create accurate base dimensions. This gives us the base to start designing the new parts from.
3) Create CAD drawings for each new part design and submit them to the forum for approval.
4) Adjust the design until you guys agree (if that’s possible)
5) Create production CAD drawings for the parts and moulds.
6) Manufacture moulds from the drawings.
7) Manufacture samples in Glass Fibre to test fit (and adjust moulds as necessary.)
8) Manufacture sample CF parts
9) Run production.

I’m prepared to cover the cost of the 3D scanning, CAD, moulds and samples etc. but I will need one of each of the original Audi parts to perform the 3D scanning on. Sorry but I'm not going to cut up my own car to do this… so does anyone have parts they can send me?; OR
Who’s prepared to chip in a deposit to cover the cost to buy each of these parts?

I’m also concerned about tolerances on part fit. I can trial fit parts to my own car to check fit and finish but who knows what tolerance the original parts are made to and whether a perfect fitting part on my car will be the same on yours? I don’t want any pissed of people because there’s a 1mm gap on a join line!

I haven’t actually looked at my car since deciding to do this so following are some questions (some of which I could have probably answered myself by walking outside… but it is night over here.)

SEAT BACKS
These concern me the most. I'm not prepared to replace the standard seat back in case it's a structural part so the only option is to make a skin/cover.
Any suggestions on how to attach the new CF cover to the seat?

REAR DIFFUSER
Are you looking for a cover to go over the existing section of the bumper or are you prepared to take a cutter to your bumper and replace this section with the new CF Part?
Cutting out the original is my personal preference so a more streamline diffuser section can be created. Going over the original will be pretty limiting on what look can be achieved.

FRONT SPLITTER
I’m assuming just a replacement of the standard part?

WING MIRRORS
Just a cover over the standard mirrors or will you have to remove the mirror and mechanism from the existing mirror and fit it into the new CF shell?

AIRBOX
Damn the GruppeM is expensive for what it is. Should we do one of these too but at a realistic price?


So in finishing, to make it practical, I’d need to make say 100pcs of any of the parts. We don't have to make all of them, just a min of 100pcs of each of whatever we do make.
The catch 22 question… Are there 99 other guys interested?

[P_G]

That's a pretty difficult last question to answer. I doubt you would have 99 people on here, however as there are 10,000 B7 RS4s globally it may be a possibility.

The other bits people may want are the two silver trim sections of the steering wheel, here in the UK these parts are £14 for the bit surrounding the buttons and £45 for the flat bottom section. I was also thinking skinned roof rails on the Avant and roof mounted antennae unit but that is obviously Avant specific.

For me this, airbox, front splitter (although I may have sorted this now)and rear diffuser are my preference. Seat back again is tricky because you have bucket and sport seat options and the seat back on both are different, so in effect if you are saying production is 100pc then really for this part it is 200 pc against 10000 cars, don't know if you would get that many interested parties to justify your costs.

[zachf88]

I'm only looking for a cover for the rear diffuser (want to keep OEM look). Cutting the diffuser from the bumper will turn out to be a total mess and making supports for the diffuser will be outrageous. Red_Rocket had a cover on his RS4 and it looked damn near perfect.

Also, for the front splitter, I had my OEM one wrapped in carbon fibre... here's a picture of it.

[rjkflyer]

Looks pretty good - i see you/they didn't bother skinning the small uprights?

Am going to skin my splitter to see how the process goes.

If it works well, might even skin the engine bay right hand cover.

At least can go buy new ones if it doesn't work...

[zachf88]

The small upright "pegs" slide into to bumper. It would have been very difficult to wrap the pegs and still have it fit like OEM.