AFR bung installation stock exhaust, Looking for where to install the exhaust bung on stock 2.0 |
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AFR bung installation stock exhaust, Looking for where to install the exhaust bung on stock 2.0 |
nditiz1 |
Sep 18 2017, 11:56 AM
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#1
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Senior Member Group: Members Posts: 1,191 Joined: 26-May 15 From: Mount Airy, Maryland Member No.: 18,763 Region Association: MidAtlantic Region |
I'll be getting my new AFR in a few days and have the stock 2.0 exhaust Liestriz. There is no 4 to 1 collector like on an extractor muffler. Can someone give me advice where to install the sensor mount? Do I need to cut a hole in the muffler? Thanks.
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Olympic 914 |
Sep 19 2017, 06:34 AM
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#2
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Group: Members Posts: 1,676 Joined: 7-July 11 From: Pittsburgh PA Member No.: 13,287 Region Association: North East States |
I thought that closer to the head was ideal. but that would mean putting it in the HE before the shrouding for the heater. On my motorcycle it is placed about 4 inches from the exhaust port.
that said, currently the sensor on my car is mounted in the Triad exhaust, probably more than 3 feet from the head. and it is a heated sensor. I have always wondered if the distance from the head could affect the accuracy of the sensor. |
jd74914 |
Sep 19 2017, 11:09 AM
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#3
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Its alive Group: Members Posts: 4,782 Joined: 16-February 04 From: CT Member No.: 1,659 Region Association: North East States |
I used to say it could be put into the tail pipe, but I was wrong, you run a good chance that the sensor will not heat up enough to give accurate readings. A heated sensor doesn't provide enough heat for an accurate reading, it only speeds up the sensor warm-up cycle. There is no magic distance from the head. In general, hotter is better, until you exceed 1030C (1886F) if you are using a Bosch LSU4.2/LSU4.9 sensor. I believe the NTK sensors go a bit higher but they aren't super common in the hobbyist market. Distance from the head is important to reduce sensor latency (delay time from reading what's actually happening) if you are doing per cycle tuning, but that's an OEM kind of thing. The heater is capable of keeping the Nernst cell hot enough wherever you put it really. The issue with putting it into a tailpipe is flow reversion pulling fresh air in and causing the sensor to read false lean. It may take a while for the sensor to heat up to the point where it gives a good reading; a heated sensor can help with that. Pretty much all sensors/aftermarket controllers these days are heated and use the elements so you don't really have to worry about that. (IMG:style_emoticons/default/smile.gif) Heating times are in the 30 to 60 second range with a decent controller. that said, currently the sensor on my car is mounted in the Triad exhaust, probably more than 3 feet from the head. and it is a heated sensor. I have always wondered if the distance from the head could affect the accuracy of the sensor. I would get a muffler with collector too and put it there if you can so you can read all cylinders. Otherwise it seems like in any of the HEX pipes like DD said would work OK, just not give you a full picture. |
Mark Henry |
Sep 19 2017, 11:31 AM
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#4
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
I used to say it could be put into the tail pipe, but I was wrong, you run a good chance that the sensor will not heat up enough to give accurate readings. A heated sensor doesn't provide enough heat for an accurate reading, it only speeds up the sensor warm-up cycle. There is no magic distance from the head. In general, hotter is better, until you exceed 1030C (1886F) if you are using a Bosch LSU4.2/LSU4.9 sensor. I believe the NTK sensors go a bit higher but they aren't super common in the hobbyist market. Distance from the head is important to reduce sensor latency (delay time from reading what's actually happening) if you are doing per cycle tuning, but that's an OEM kind of thing. The heater is capable of keeping the Nernst cell hot enough wherever you put it really. The issue with putting it into a tailpipe is flow reversion pulling fresh air in and causing the sensor to read false lean. It may take a while for the sensor to heat up to the point where it gives a good reading; a heated sensor can help with that. Pretty much all sensors/aftermarket controllers these days are heated and use the elements so you don't really have to worry about that. (IMG:style_emoticons/default/smile.gif) Heating times are in the 30 to 60 second range with a decent controller. that said, currently the sensor on my car is mounted in the Triad exhaust, probably more than 3 feet from the head. and it is a heated sensor. I have always wondered if the distance from the head could affect the accuracy of the sensor. I would get a muffler with collector too and put it there if you can so you can read all cylinders. Otherwise it seems like in any of the HEX pipes like DD said would work OK, just not give you a full picture. I used to think that as well. (IMG:style_emoticons/default/smile.gif) Thinking of building and maybe selling my own meters. So I've done a fair bit of research on the 4.9 LSU. (IMG:style_emoticons/default/wink.gif) |
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