A Generous Gift From Gent

[MikeT 744]

Ian (Gent) was kind enough to give me a BRABUS dual exhaust and valence last weekend. It's all heavily used of course but still, that was very nice of him !

[David_18 13]

I haven't done anything to the smart recently but Ian (Gent) was kind enough to give me a BRABUS dual exhaust and valence last weekend. It's all heavily used of course but still, that was nice!

Brabus exhaust ! This kind of exhaust (or a another one) still available some where ?

[MikeT 744]

I think some replicas might be available but the BRABUS diesel exhaust was sold out in 2007.

[bilgladstone 13]

Very good of Gent! Will you polish that up and install it on the white car?Bil

[MikeT 744]

Maybe, we will see if the rattle can be cured first. It's metallic, not the honeycomb. Needs some SS welding where the inner baffles have detached from the outer skin (small holes). The tips are chrome and badly pitted (but not rusty). Those would need some work too, rechroming. He gave me the plastic OE 450 BRABUS heat shield too, in great condition.

[bilgladstone 13]

If you find a chrome place that doesn't want to rob you blind, please let me know.Bil

[MikeT 744]

I probably won't, so I'll likely sand them and paint them flat black.

[bilgladstone 13]

Powder coating would be more durable. Not very expensive either.B

[MikeT 744]

I think the exhaust will get too hot for the powder coating, no?

[Huronlad 186]

There are powder coat paints designed for headers and exhausts.

[bilgladstone 13]

The next exhaust kit I build will be ceramic coated, inside and out. There is a company nearby that does this.

But I won't need to do this for quite a while, happily, as my current exhaust is exceeding my expectations.

B:sun:

[MikeT 744]

Exhaust powder coat it is then. I was thinking that flat black would be better anyway, because the tips will be so sooty (even a non-remapped smart). But first the integrity of the canister has to be assessed. I may do that next year.

[MikeT 744]

Exhaust powder coat it is then. I was thinking that flat black would be better anyway, because the tips will be so sooty (even a non-remapped smart). But first the integrity of the canister has to be assessed. I may do that next year.

A little examination reveals that under the chrome, the tips are stainless steel, so I will simply sand off the pitted chrome and polish up the SS. Bonus! I think the canister is fine and just needs some minor surgery and the new vibration damper and hanger strap.

[MikeT 744]

I decided to split this topic off from the "what did you do to your smart" thread because it's taking on a life of its own.I was speaking with a guy at work today (the one with the Doppelkabine Unimog U427) and he told me that repairing the SS exhaust should be fairly easily done, he has done similar work inside opened Ducati SS exhaust canisters. That's good news....I spent a little time Monday evening cleaning the exhaust canister with Flitz paste and it now has a mirror-like sheen over most of it. I also did some more work on one of the exhaust tips, grinding the chrome off and polishing up the stainless and it's going to look great! However, it's going to be quite time-consuming, especially if I do that to the entire tip (not just the very ends, where the chrome is most pitted).I'll take a couple of photos tonight and post them here.Does anyone know if the catalyst inside a diesel exhaust are sensitive to certain cleaning chemicals or even hydrocarbon solvents? I need to clean all the soot out of these somehow, after surgery (or possibly before If I can do it myself at home).

[TO Ed 9]

I don't kmow of any solvents or other chemicals that would clean inside the honeycomb structure. If you can remove it the best solution may be to put it inside a hot wood stove to burn it off. Otherwise I would rely on your next highway drive to burn it off.

[Alex 21]

My smart is mapped, so I could burn out the honeycomb for you. Might take me 100K km to do a good job, though...Nice gift, and actually it suits Snowball better than me. But I thought Snowball was to remain stock as the special edition it is?

[TO Ed 9]

Mike, the following is quoted directly from wikipedia in response to your question re sensitivity of the catalyst:Catalyst poisoning occurs when the catalytic converter is exposed to exhaust containing substances that coat the working surfaces, encapsulating the catalyst so that it cannot contact and treat the exhaust. The most-notable contaminant is lead, so vehicles equipped with catalytic converters can be run only on unleaded fuels. Other common catalyst poisons include fuel sulfur, manganese (originating primarily from the gasoline additive MMT), and silicone, which can enter the exhaust stream if the engine has a leak that allows coolant into the combustion chamber. Phosphorus is another catalyst contaminant. Although phosphorus is no longer used in gasoline, it (and zinc, another low-level catalyst contaminant) was until recently widely used in engine oil antiwear additives such as zinc dithiophosphate (ZDDP). Beginning in 2006, a rapid phaseout of ZDDP in engine oils began.[citation needed] Depending on the contaminant, catalyst poisoning can sometimes be reversed by running the engine under a very heavy load for an extended period of time. The increased exhaust temperature can sometimes liquefy or sublimate the contaminant, removing it from the catalytic surface. However, removal of lead deposits in this manner is usually not possible because of lead's high boiling point. Any condition that causes abnormally high levels of unburned hydrocarbons—raw or partially burnt fuel—to reach the converter will tend to significantly elevate its temperature, bringing the risk of a meltdown of the substrate and resultant catalytic deactivation and severe exhaust restriction. Vehicles equipped with OBD-II diagnostic systems are designed to alert the driver to a misfire condition by means of flashing the "check engine" light on the dashboard.

[TO Ed 9]

And here is some more interesting info on the type of catalytic converter used in diesel engines (also taken directly from wikipedia)...For compression-ignition (i.e., diesel engines), the most commonly used catalytic converter is the Diesel Oxidation Catalyst (DOC). This catalyst uses O2 (oxygen) in the exhaust gas stream to convert CO (carbon monoxide) to CO2 (carbon dioxide) and HC (hydrocarbons) to H2O (water) and CO2. These converters often operate at 90 percent efficiency, virtually eliminating diesel odor and helping to reduce visible particulates (soot). These catalysts are not active for NOx reduction because any reductant present would react first with the high concentration of O2 in diesel exhaust gas. Reduction in NOx emissions from compression-ignition engines has previously been addressed by the addition of exhaust gas to incoming air charge, known as exhaust gas recirculation (EGR). In 2010, most light-duty diesel manufacturers in the U.S. added catalytic systems to their vehicles to meet new federal emissions requirements. There are two techniques that have been developed for the catalytic reduction of NOx emissions under lean exhaust conditions - selective catalytic reduction (SCR) and the lean NOx trap or NOx adsorber. Instead of precious metal-containing NOx adsorbers, most manufacturers selected base-metal SCR systems that use a reagent such as ammonia to reduce the NOx into nitrogen. Ammonia is supplied to the catalyst system by the injection of urea into the exhaust, which then undergoes thermal decomposition and hydrolysis into ammonia. One trademark product of urea solution, also referred to as Diesel Emission Fluid (DEF), is AdBlue. Diesel exhaust contains relatively high levels of particulate matter (soot), consisting in large part of elemental carbon. Catalytic converters cannot clean up elemental carbon, though they do remove up to 90 percent of the soluble organic fraction[citation needed], so particulates are cleaned up by a soot trap or diesel particulate filter (DPF). Historically, a DPF consists of a Cordierite or Silicon Carbide substrate with a geometry that forces the exhaust flow through the substrate walls, leaving behind trapped soot particles. Contemporary DPFs can be manufactured from a variety of rare metals that provide superior performance (at a greater expense).[17] As the amount of soot trapped on the DPF increases, so does the back pressure in the exhaust system. Periodic regenerations (high temperature excursions) are required to initiate combustion of the trapped soot and thereby reducing the exhaust back pressure. The amount of soot loaded on the DPF prior to regeneration may also be limited to prevent extreme exotherms from damaging the trap during regeneration. In the U.S., all on-road light, medium and heavy-duty vehicles powered by diesel and built after January 1, 2007, must meet diesel particulate emission limits that means they effectively have to be equipped with a 2-Way catalytic converter and a diesel particulate filter. Note that this applies only to the diesel engine used in the vehicle. As long as the engine was manufactured before January 1, 2007, the vehicle is not required to have the DPF system. This led to an inventory runup by engine manufacturers in late 2006 so they could continue selling pre-DPF vehicles well into 2007.[18]

[MikeT 744]

Thanks Ed for the information! Maybe I'll leave the internal cleaning up to whomever does the canister surgery. Right now I am thinking of getting the local Midas shop to do it, because they did a good crack repair on my Peugeot 405's SS exhaust some years ago.To answer Alex's question, I certainly would put this on the Canada 1, in fact I was disappointed (but not surprised) when I saw the Canada 1s all had regular peashooter exhausts. In any case, it is a reversible modification and I will be keeping the original exhaust and valence.I will probably also remap the car next year at Eddy's....

[MikeT 744]

Here are some shots of the exhaust canister and valence.The lefthand exhaust tip has been cleared of its chrome and has been roughly sanded by me; the righthand one has the original chrome that's pitted. I wonder why they chromed the tips in the first place, it's all stainless steel.The close-up shows where the inner framework has separated from the skin, and the internal metallic rattle is located.

[Coast Steve 1]

That should be on my car I even have a dual output valance all ready and waiting.AHHHHHHHHHH

Edited December 12, 2012 by Coast Steve

[bilgladstone 13]

OOH... shiny, shiny! A long, hot run on the highway will clean the soot out of the cat'.

A tip: spring-mount the flange to help keep the downpipe weld from cracking. It permits a little movement instead of causing metal fatigue and doesn't leak if done properly.

Bil

[MikeT 744]

That's a good idea Bil, where did you get that hardware?

Steve, there is one for auction in Germany right now, currently at 201 Euros (doesn't look as good as mine but it's apparently repaired): http://www.ebay.de/itm/Brabus-Sportauspuff...1#ht_500wt_1219

[bilgladstone 13]

My local muffler shop sorted out the bolts, springs and washers for me. I'm pretty sure any decent custom muffler shop can help you out.B

[Coast Steve 1]

I like that idea Bil, My setup used "stainless nylock nuts" instead and a flex section in there too.But is yours like that just becuase there's no flex pipe installed? I wonder how all my Systems are doing (on these 2 bolts stayng tight I mean)