The basic function of a cat is to burn the unburnt fuel in the exhaust. Newer cats also convert some other by products of combustion to co2 and water vapor.
http://auto.howstuffworks.com/catalytic-converter.htm
catalytic converter
- Thread starter kenjrbanga
- Start date
The basic function of a cat is to burn the unburnt fuel in the exhaust. Newer cats also convert some other by products of combustion to co2 and water vapor.
http://auto.howstuffworks.com/catalytic-converter.htm
Just got a second opinion on my check engine / cat converter issue. My nsx does not even have the catalytic converter on it. It has straight pipe on it. I guess I better stick with this shop that gave me 2nd opinion.
LOL, Yes I would assume not having a cat would cause a error.
Well my smog test notification just came in.
I have 2 STMPO exhausts and I was going to take the damaged one and replace the 2 mufflers with 2 of Magnaflow CA-legal cats that are larger than the OEM cats.
I like to test my theory that although the cats are a couple of feet further down the exhaust than the OEM location that they should be able to pass the sniffer based on the following:
1. New cats
2. Larger cats
3. There is less heat being lost in the exhaust piping prior to the cats from my double-layered and double sided ceramic coating that is rated at a 55% reduction of heat being transferred/radiated
The average light off temperature at which the catalytic converter begins to function ranges from 400 to 600 degrees F. The normal operating temperature can range up to 1,200 to 1,600 degrees F. I'll take my laser IR thermo reader to take some measurements.
I just bought 2 of the Magnaflow 36009 cats for $109 each (had Summitracing.com beat the price from www.truckpartshub.com.
I should see the cats tomorrow.
Also, it would be interesting to see how the NSX will sound with no mufflers and larger cats.
I have 2 STMPO exhausts and I was going to take the damaged one and replace the 2 mufflers with 2 of Magnaflow CA-legal cats that are larger than the OEM cats.
I like to test my theory that although the cats are a couple of feet further down the exhaust than the OEM location that they should be able to pass the sniffer based on the following:
1. New cats
2. Larger cats
3. There is less heat being lost in the exhaust piping prior to the cats from my double-layered and double sided ceramic coating that is rated at a 55% reduction of heat being transferred/radiated
The average light off temperature at which the catalytic converter begins to function ranges from 400 to 600 degrees F. The normal operating temperature can range up to 1,200 to 1,600 degrees F. I'll take my laser IR thermo reader to take some measurements.
I just bought 2 of the Magnaflow 36009 cats for $109 each (had Summitracing.com beat the price from www.truckpartshub.com.
I should see the cats tomorrow.
Also, it would be interesting to see how the NSX will sound with no mufflers and larger cats.
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http://vimeo.com/26463578
This is what an NSX sounds like without mufflers or cats
Of course this engine is heavily built out with ITB's, pistons, cams etc but it sounds pretty badass lol
This is what an NSX sounds like without mufflers or cats
Of course this engine is heavily built out with ITB's, pistons, cams etc but it sounds pretty badass lol
http://vimeo.com/26463578
This is what an NSX sounds like without mufflers or cats
Of course this engine is heavily built out with ITB's, pistons, cams etc but it sounds pretty badass lol
Mines sounds louder and deeper with my high boost SOS SC, RM racing headers (largest collectors in any NSX headers at 2.5" per side) and STMPO (BATMANs edition mufflers). It's the ONLY NSX to have set off the shop alarm at Driving Ambition. And trust me Driving Ambition has much crazier race-ONLY NSXs there than urs and mines.
Even Shad's son knows just how loud my exhaust is.
I'm still looking for a good video camera that can document the sound of my exhaust system without sounding distorted.
Are there any aftermarket cats that are similar to OEM? I glanced at angus and not sure what kind his are. I should take time to read his thread. I have hi flow cats and not the biggest fan of them. Already have headers, exhaust, intake and would rather minimize some of the noise and smell too haha
Magnaflow is suppose to have OBD-II California legal cats for the new NSXs, but you will need to input your year to get an exact match. I don't think it's an angled cat like the ones below, but a universal cat that they tested and determined that will meet CA smog requirements.
These 2 Magnaflow cat options are Pre-OBD-II and should work for the 94 and older NSX:
IN/OUT PART#
2" 91074
2.25" 91075
2.50" 91076
EPA-FEDERAL ENGINE LIMIT: 256 CID/4.2L
TEST WEIGHT: 4500 lbs.
IN/OUT PART#
2" 91084
2.25" 91085
2.50" 91086
EPA-FEDERAL ENGINE LIMIT: 256 CID/4.2L
TEST WEIGHT: 4500 lbs.
Ebay sells these cats for around $75.
If anyone has a pair of bad/old/defective/clogged cats lying around that they want to part with, PM me.
I need a pair to use as a pattern template to create test pipes.
George
I need a pair to use as a pattern template to create test pipes.
George
magnaflow cats suck, they break down in 2 years and you need new ones again to pass, if you are obd1 i would say go with the Honda Renault cats sold by HyTech. supposedly OEM from back in the day when cars were filthy, loaded with precious metals and such to clean up those clunkers. $175 each and it needs to be welded on. for that price you might find used stock cats, though.
but in Florida, get yo straight pipe on...
but in Florida, get yo straight pipe on...
This is the first I've heard about magnaflow cats.
Also, most of the aftermarket "high flow" cats seem to use the high flow magnaflow cats as their base product.
Thanks for the responses! I'll see how I feel after a couple days. Luckily there is no drone and it really doesn't get too loud unless I open it up. I've had previous setups in other cars that had drone and gave me headaches at first (eventually got over it) but I'm alright with this. Just don't want to be obnoxious to other drivers, that's all.
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the cats wont give you drone... it depends on the exhaust you're running...
that's the case with any high flow cat i've used or ever heard about... not worth it. just run test pipes and swap come smog time.
Now that made me laugh. I'm pretty surprised your first mechanic didn't even look and see the lack of cats. Maybe it was just a bad day or he was in a rush. Anyway, throwing an O2/cat code is pretty common when running test pipes in place of the cats. Most aftermarket test pipes have some kind of extender tube that mounts the O2 sensor further out of the main exhaust stream. This prevents the sensor getting fouled and also makes the sensor "think" the cats are in place and working properly. If the check-engine light keeps returning, have someone who is familiar with test pipes take a look. It's pretty easy to modify the pipe with home depot parts if the anti-fouling tube is not long enough or if your test pipes don't have them.
I know they don't sniff emissions in Orlando but that could eventuallly change. They used to do emissions testing in Jacksonville when I lived there many years ago, because J'ville was in a region that was on the EPA shit list for air quality. I don't think that's the case any more.
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