NC RS Street Header - ok for track or no?

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VernonA420
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Location: DFW, Texas

NC RS Street Header - ok for track or no?

Post by VernonA420 »

I was reading about the RoadsterSport Street Header for the NC and I noticed that the description for the ceramic coated one here http://www.good-win-racing.com/Mazda-Pe ... 1155C.html says "Converter has two year warranty (normally aspirated street cars only, NOT recommended for supercharged or track driven cars), ..." whereas the one without ceramic coating here http://www.good-win-racing.com/Mazda-Pe ... -1155.html says "Converter has two year manufacturing defect warranty (normally aspirated cars only, NOT recommended for supercharged cars), ..."

It's the same catalytic converter, but only the coated one says it's not recommended for track driven cars.

Is there a concern for a track driven car, and if so, what is it?

Thanks!
Brian
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Re: NC RS Street Header - ok for track or no?

Post by Brian »

Same for both, not recommended for track cars to have converter inches from exhaust valves...too much heat in that application and that burns out the cats fast.
Brian Goodwin
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VernonA420
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Re: NC RS Street Header - ok for track or no?

Post by VernonA420 »

Thank you. I'll go with a catless header when I eventually upgrade.
hsy
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Re: NC RS Street Header - ok for track or no?

Post by hsy »

Brian wrote:Same for both, not recommended for track cars to have converter inches from exhaust valves...too much heat in that application and that burns out the cats fast.
Would you not recommend it even if I only do 1 hpde every other month on an n/a setup?
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Re: NC RS Street Header - ok for track or no?

Post by Brian »

hsy wrote:
Brian wrote:Same for both, not recommended for track cars to have converter inches from exhaust valves...too much heat in that application and that burns out the cats fast.
Would you not recommend it even if I only do 1 hpde every other month on an n/a setup?
Would you beat yourself over the head with a hammer....even if only once every other month?

Still dumb thing to do right?
Brian Goodwin
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BrentM735
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Re: NC RS Street Header - ok for track or no?

Post by BrentM735 »

Isn't the converter further from the valves in the RS street header than the oem header? Are you saying it is equally bad to run an oem header on track? Is there something about the RS catted header that makes it worse to run on track than the oem header? I ask because I and others probably run the oem header on track (hpde, not dedicated track car) pretty often.
Brian
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Re: NC RS Street Header - ok for track or no?

Post by Brian »

The factory put converter in header so it lights off fast to do the job of controlling emissions on a STREET CAR. It's a disaster for track use, we were burning up the stock cats on track on NC that were 3 weeks old back in year 2006. The RS header is a better on this because we move the converter further down in that header design, but still called 'STREET header' for good reason, generally no catted header is appropriate for track. Sorry, no easy way around the fact that cat in the header is bad for track, RS will last longer but still die early in track use.
Brian Goodwin
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BrentM735
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Re: NC RS Street Header - ok for track or no?

Post by BrentM735 »

Thank you for the info Brian, that is the info I was looking for.

You should consider updating the product description on your website as it makes it sound like it is okay to do the occasional track day with the header. I read the disclaimer as "not recommended for heavy autocross or heavy track use." I would have not purchased this header had I known it would prevent me from taking the car on the track.

Quote from the product page:
"(normally aspirated cars only, NOT recommended for supercharged cars or heavy autocross/track use)"
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Re: NC RS Street Header - ok for track or no?

Post by Brian »

I will delete 'heavy' because it is redundant and vague in that sentence since track use is heavy by definition. Catted header does not prevent you from taking it on track, you just need to understand in going into track use that you are going to use up the life of things faster on the car in track use, including the converter and the tires, life of the oil, life of the engine, the brake pad life, the brake rotor life, etc. That all seems the subject of common sense to me, but I have been surprised on this before. I had a track weekend where a guy with stock miata was shocked to his foundations that he had killed the stock tires by end of the weekend. He had drifted his ND pretty well for a beginner, but every session full throttle sideways and drifting corners meant he was looking at the tire steel belts by late Sunday afternoon. He was surprised, and those of us doing track days often were shocked that he was shocked.

Knowing that they die fast in track use most race cars do not have converters. But WRC and the various rally groups decided to require them for emissions reductions and that the way to do it in a race car was to place their catalytic converters at the rear of the car, because the further back it is mounted the cooler it will operate and the longer it will survive. And it makes tech inspection easy, they can see it in the tailpipe. And it looks cool when glowing at night stage starts.

Rally Fiat 124 (ND Miata chassis) with tailpipe converter.
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rally_cat_exhaust_tip.jpg (177.11 KiB) Viewed 7323 times
Brian Goodwin
Good-Win Racing
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