What did you do to your NBS GMT800 Tahoe/Yukon Today?

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SnowDrifter

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Trans seems to run 3 maybe 4 degrees higher with the filter. Difficult to tell if it's a flow reduction thing, or the fact the filter is mounted in the middle of a hot air stream. 97 ambient, 137-138f trans Temps @75mph. Pre filter under same conditions was 134 give or take. No notable downsides otherwise, still have the improved consistency in shift feel at light and heavy throttle input


Also hi from hiatus
 

Sam Harris

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Trans seems to run 3 maybe 4 degrees higher with the filter. Difficult to tell if it's a flow reduction thing, or the fact the filter is mounted in the middle of a hot air stream. 97 ambient, 137-138f trans Temps @75mph. Pre filter under same conditions was 134 give or take. No notable downsides otherwise, still have the improved consistency in shift feel at light and heavy throttle input


Also hi from hiatus
Welcome back!
 

Rocket Man

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Trans seems to run 3 maybe 4 degrees higher with the filter. Difficult to tell if it's a flow reduction thing, or the fact the filter is mounted in the middle of a hot air stream. 97 ambient, 137-138f trans Temps @75mph. Pre filter under same conditions was 134 give or take. No notable downsides otherwise, still have the improved consistency in shift feel at light and heavy throttle input


Also hi from hiatus
Where ya been?
 

iamdub

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Aha. The great treasure trove of knowledge. I started to think you used to work at an exhaust shop in a prior life. Should have known better. :D

Lol

Nah, it's just one of those things that fascinated me so I geeked out on it. I've never gotten the impression from any exhaust shop worker that they could even begin to use compound mathematical formulas!

When it comes to exhaust, everyone's all about swapping muffler after muffler to balance a certain sound with no drone and that usually means they end up compromising with a quieter muffler than what they originally wanted. With two minutes of calculations and $10 in materials, you can keep the muffler/sound you want and target just the sound you don't want.
 

Sam Harris

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Lol

Nah, it's just one of those things that fascinated me so I geeked out on it. I've never gotten the impression from any exhaust shop worker that they could even begin to use compound mathematical formulas!

When it comes to exhaust, everyone's all about swapping muffler after muffler to balance a certain sound with no drone and that usually means they end up compromising with a quieter muffler than what they originally wanted. With two minutes of calculations and $10 in materials, you can keep the muffler/sound you want and target just the sound you don't want.
Yeah I tried to get my exhaust guy to make me one. That’s not happening unless I tell him I’ll pay a lot to get it done. Lol. He’s going to get a factory resonator that was deleted from another vehicle to try it out. [emoji53] not sure how that will go, but it’s definitely not going to be 25.2” like it’s supposed to be. OTOH, I suspect the factory resonators have a longer chamber than they appear to. Perhaps.. hopefully it helps. We’ll see in a couple weeks when I can get back in to give it a shot.
 

iamdub

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Yeah I tried to get my exhaust guy to make me one. That’s not happening unless I tell him I’ll pay a lot to get it done. Lol. He’s going to get a factory resonator that was deleted from another vehicle to try it out. [emoji53] not sure how that will go, but it’s definitely not going to be 25.2” like it’s supposed to be. OTOH, I suspect the factory resonators have a longer chamber than they appear to. Perhaps.. hopefully it helps. We’ll see in a couple weeks when I can get back in to give it a shot.


Strange that he wouldn't make one being how simple it is. It's just a straight piece of pipe that's capped off and welded to the existing pipe. With a hole in that pipe, of course. Maybe because the idea is foreign to him? It does seem weird, though. After all, it's "just a straight piece of pipe that's capped off and welded to the existing pipe".

The factory (Tahoe/Yukon) resonator is a 1/4 wave resonator. It's just a pipe wrapped around a pipe instead of a pipe extending perpendicularly off of another pipe- for packaging purposes. I don't know what it's target (center) frequency is, but it'd be whatever was produced with a stock exhaust at cruising RPM, so you at least have that similarity. Definitely worth a shot.
 

Sam Harris

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Having a hard time finding the efan harness I want to convert. I know I definitely do not want the Nelson kit, since it likes to burn down trucks.. so since I haven’t been able to reach @ScottyBoy, I’m looking around elsewhere..

Does anyone have any experience with either of these? Or any knowledge? Good / bad..?


https://www.pcmofnc.com/product/2003-2013-full-size-truck-dual-fan-conversion-kit-3/


https://www.bp-automotive.com/product/1999-2006-gm-trucksuv-fan-harness/

Any feedback is much appreciated. I’m also 100% open to cleaning up a factory setup, and replacing anything needing attention, I can solder / wire, etc.. just fine, but there are so few NBS trucks in my junkyards around here, that it’s really tough to find one there as well.
 

Tonyrodz

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Having a hard time finding the efan harness I want to convert. I know I definitely do not want the Nelson kit, since it likes to burn down trucks.. so since I haven’t been able to reach @ScottyBoy, I’m looking around elsewhere..

Does anyone have any experience with either of these? Or any knowledge? Good / bad..?


https://www.pcmofnc.com/product/2003-2013-full-size-truck-dual-fan-conversion-kit-3/


https://www.bp-automotive.com/product/1999-2006-gm-trucksuv-fan-harness/

Any feedback is much appreciated. I’m also 100% open to cleaning up a factory setup, and replacing anything needing attention, I can solder / wire, etc.. just fine, but there are so few NBS trucks in my junkyards around here, that it’s really tough to find one there as well.
I've read here that the nnbs fans work on the nbs also.
These guys were popular for awhile.20200627_133749.jpg
I just checked out their non ebay page and didn't see much of anything on there. Maybe their doing more ebay stuff now.

This is oem/used parts.
 
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