Superleggera Rear Diffuser?

Despite this, the car is just f'in awesome!

 

mine had the same issues but even worse because of the TT.

hershel made me half circle plates powdercoated black so you can barely see.

 

That sounds better. I noticed in another thread where it was almost a chrome or silver plate and stuck out like a sore thumb.

 

I still think Lambo should fix it or provide a solution like Hershel's plate.

mine had the same issues but even worse because of the TT.

hershel made me half circle plates powdercoated black so you can barely see.

 

Could you share on how are those plates are mounted please?

Could you share on how are those plates are mounted please?

 

my car is on its way to sarasota, but in a few weeks i would be more then happy to post pics.

 

my car is on its way to sarasota, but in a few weeks i would be more then happy to post pics.

 

Thanks! Looking forward to them.

How about a pipe slipped over the present exhaust pipe creating an air gap between the pipes .

How about a pipe slipped over the present exhaust pipe creating an air gap between the pipes.

 

How about getting the exhaust tips coated with a black header coating? It should significantly reduce the surface temperatures of the tips thus significantly lower the surface temperatures of the carbon fiber diffuser directly underneath it. I don't recall any yellowing with my Superleggera, but I'll check and report back..

 

-R

Anybody thought of 3M clear bra the rear diffuser? Perhaps that would be the cheapest way to go.

Although I don't own a SL (have a '06 G), thought I'd chime in given that I am a composite guy (Masters in Composites and have been working in that field for 25 years).

 

I noticed this yellowing on a SL at the track a few weeks ago. It is not the carbon fiber or the resin but it is the clear coat that has been sprayed over the part. Appears that Lamborghini did their homework and the resin used on that part is high temp otherwise, you would be seeing other issues given the heat of the exhaust. Appears that they sparyed it with a standard automotive clear coat and that is what is getting rough and yellowing. Not a heck of a lot that is going to be done in that high heat area other then add some metal plates to shield and hide it! The diffuser should have been designed with a little more clearance in that area but hind sight is easy.

 

For the record, carbon fiber itself is pretty much inert and temp stable up over 1000F. The resin system used to give it form is going to be the week link on temp performance. Most resin systems have UV inhibitors in them these days to guard against discoloration from UV, nothing special or expensive. If Lamborghini was not using proper UV protection in their carbon bits, the interior in the SL's would be looking like hell already! The carbon work on the SL's is top quality from all that I have looked over and given what I do for a living, I have a critical eye! Much nicer work then I have seen coming out of Ferrari!

Although I don't own a SL (have a '06 G), thought I'd chime in given that I am a composite guy (Masters in Composites and have been working in that field for 25 years).

 

I noticed this yellowing on a SL at the track a few weeks ago. It is not the carbon fiber or the resin but it is the clear coat that has been sprayed over the part. Appears that Lamborghini did their homework and the resin used on that part is high temp otherwise, you would be seeing other issues given the heat of the exhaust. Appears that they sparyed it with a standard automotive clear coat and that is what is getting rough and yellowing. Not a heck of a lot that is going to be done in that high heat area other then add some metal plates to shield and hide it! The diffuser should have been designed with a little more clearance in that area but hind sight is easy.

 

For the record, carbon fiber itself is pretty much inert and temp stable up over 1000F. The resin system used to give it form is going to be the week link on temp performance. Most resin systems have UV inhibitors in them these days to guard against discoloration from UV, nothing special or expensive. If Lamborghini was not using proper UV protection in their carbon bits, the interior in the SL's would be looking like hell already! The carbon work on the SL's is top quality from all that I have looked over and given what I do for a living, I have a critical eye! Much nicer work then I have seen coming out of Ferrari!

 

What if we ceramic coat the exhaust and redo the clear coat on the carbon fiber rear diffuser? Would that prevent the situation happen again?

What if we ceramic coat the exhaust and redo the clear coat on the carbon fiber rear diffuser? Would that prevent the situation happen again?

 

Ceramic coating would keep more heat in the exhaust gas and allow the pipe itself to heat up less, it is a great insulator as you probably already know from its use on headers. It would help on the heat front.

 

As for redoing the clear coat, paint shop would have to strip the clear that is there to get rid of the yellow and not sand into the carbon in the least otherwise they would distort the pattern of the twill woven surface. yes, can be done but needs to be a very careful body guy who pays attention to the details. Would not want the shop monkey doing the sanding!

Ceramic coating would keep more heat in the exhaust gas and allow the pipe itself to heat up less, it is a great insulator as you probably already know from its use on headers. It would help on the heat front.

 

As for redoing the clear coat, paint shop would have to strip the clear that is there to get rid of the yellow and not sand into the carbon in the least otherwise they would distort the pattern of the twill woven surface. yes, can be done but needs to be a very careful body guy who pays attention to the details. Would not want the shop monkey doing the sanding!

 

Elise,

Thank you very much for your quick response and useful information. What's the best way to prevent the yellowing from the exhaust without the metal plate? Please post your suggestion. Thanks again for your help.

Ron or anyone else having these issues send me a PM and I can sort you out with the same heat shieldds we provide with our own diffusor very inexpensively. As Bill said if you dont like the stainless finish we can do the shields in any color ..

 

 

Wouldn't that metal plate heat up and spread the yellowing futher? Those nails holding the metal plate looks to weaken the carbon fiber (please elaborate). IMO it doesn't look that good and that's why they hammer these things on the bottom of the shoes Plus I don't want to add more weight to the Superleggera Any other way we can keep the car in stock form and get this problem resolve?

Anybody thought of 3M clear bra the rear diffuser? Perhaps that would be the cheapest way to go.

 

Hey Pokie,

 

Got your message. Mine is also looking a bit rough.

I tried the clear bra material and it doesn't work. It bubbled

up after a few minutes and looked far worse.

 

I saw the original chrome plates that RSC made and they

looked ok at best, maybe black would be better but

I would have to reserve judgement unitl I see it with my own eyes.

 

Pete

Elise,

Thank you very much for your quick response and useful information. What's the best way to prevent the yellowing from the exhaust without the metal plate? Please post your suggestion. Thanks again for your help.

 

To be honest, it is going to be damn tough to keep it from happening without extending the exhaust pipe so the heat is beyond the diffuser or removing a section of the diffuser in that area. I wish I had a good answer for you guys. The metal plates will work to deflect the heat and protect it. We could also build some high temp carbon plates but they would not be high gloss so, would have the same look as the metal plates of an added on item, just with a carbon woven pattern instead of the metal.

 

The ultimate solution is a redesign of the rear diffuser to give a little clearance in that area of the pipe. Don't think Lambo is going to do this as it would cost several 100K to do it right and as we already know, Lambo is calling this "normal wear and tear".

 

I'll sleep on it and see if I come up with any brilliant solutions but a metalic plate is probably the best option! Could be something attached to the bottom of the exhaust pipe itself and if someone was really tricky, maybe easily removable for when the car is just sitting looking pretty!

My SL is at 9500 miles and I'm seeing this as well. As far as I understand, it is common place and should be expected on any and all SLs. I spoke with 2 different dealerships and it is not covered under warranty. When you break down what is actually happening, it is not depreciating the value of the car, since all of the SLs face this issue, and it is not so noticable that people will point and stare. I would say to just drive and not put so much thought into it..

Here is an update to the diffuser issue. My dealership has attempted to fix the yellowing / burn marks by having their body shop sand the clear coat short of affecting the carbon fiber. The body shop has indicated this process removed only 20% of the yellowing / burn marks. I spoke with them directly and they believe most of the problem lies in the resin and beneath the clear coat. He indicated something to the effect of the combination of the ambient heat along with the heat from the pipes is not allowing dissipation of heat in that specific area and causing the yellowing from underneath.

 

The exhaust pipes are already high temp ceramic coated as told to me by several Lambo reps and body shop people. After doing some research on possible solutions, I found a product used on the Reventon and SV called Zircotec. I'm not sure if this was also used on the SL and whether it would provide any additional thermal insulation or barrier to the ceramic coating if different. Zircotec has a page on their site which explains the product in greater detail.

 

For reasons other than just the yellowing, my dealer has replaced my diffuser with an "untarnished unit" which I would prefer to keep that way. I'll continue to look for a solution, if there is one. I'm heading to Roebling Raceway this wekend for a couple days of track time and will insulate the pipes with some titanium wrap to try to reduce the heat damage.

Here is an update to the diffuser issue. My dealership has attempted to fix the yellowing / burn marks by having their body shop sand the clear coat short of affecting the carbon fiber. The body shop has indicated this process removed only 20% of the yellowing / burn marks. I spoke with them directly and they believe most of the problem lies in the resin and beneath the clear coat. He indicated something to the effect of the combination of the ambient heat along with the heat from the pipes is not allowing dissipation of heat in that specific area and causing the yellowing from underneath.

 

The exhaust pipes are already high temp ceramic coated as told to me by several Lambo reps and body shop people. After doing some research on possible solutions, I found a product used on the Reventon and SV called Zircotec. I'm not sure if this was also used on the SL and whether it would provide any additional thermal insulation or barrier to the ceramic coating if different. Zircotec has a page on their site which explains the product in greater detail.

 

For reasons other than just the yellowing, my dealer has replaced my diffuser with an "untarnished unit" which I would prefer to keep that way. I'll continue to look for a solution, if there is one. I'm heading to Roebling Raceway this wekend for a couple days of track time and will insulate the pipes with some titanium wrap to try to reduce the heat damage.

 

Ron,

Thanks for the update! Don't forget to post some pictures and videos of the Superleggera at the track. Be safe and have fun!

 

I'm heading to Roebling Raceway this wekend for a couple days of track time and will insulate the pipes with some titanium wrap to try to reduce the heat damage.

 

Ron,

 

You will need to directly protect the carbon fiber from the heat of the exhaust gas itself to really be safe. Either a metal plate over the carbon (something bent up quick at a sheet metal shop and held on with racer tape would work) or an extension on the bottom of the exhaust pipe itself to deflect the heat away from the carbon. Feel a large part of the problem is the actual exhaust gasses themselves, not just the hot exhaust tips!

 

Have fun, the G in any form is a riot on the track! Shiny side up!

 

Steve

Steve, thanks for your input and advice. I found these "heat shields" on Cargraphic's web site under the exhaust system for the SL. Do you think these will work at deflecting heat from the diffuser?

 

http://www.cargraphic.co.uk/index.php?/s,6...,132,4732,4733/

 

Steve, thanks for your input and advice. I found these "heat shields" on Cargraphic's web site under the exhaust system for the SL. Do you think these will work at deflecting heat from the diffuser?

 

http://www.cargraphic.co.uk/index.php?/s,6...,132,4732,4733/

 

 

Ron,

I think Lamborghini should provide you some funds to get this issue resolved. I don't mind the yellowing as it looks rugged and raw but if it will weakening the structure of the carbon fiber or catch fire then I think they owe us an answer. Sometimes I just don't know how to support an exotic brand like the Lamborghini if they don't even stand behind their product. I have heard someone with a Superleggera with bubbling in the paint which locate right on the top of the exhaust.

I have had OEM CF diffuser for 2months and with no cats so have flames every now and then and also track days. So far i've been monitoring the colour it looks ok but will be putting a metal plate as many have suggested.