What did you do to your NNBS GMT900 Tahoe/Yukon Today?

Doubeleive said:

I would have to build a cardboard funnel behind it to get a accurate reading. i haven't bought one yet either just thinking,,,,,,,,

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Why a cardboard funnel? You don't drive down the road with a cardboard funnel taped to the front of the truck do you?

Simulate driving down the highway.
Box fan set to same speed during both tests. Place grill like a foot away during each test and take reading like a foot behind the grill.

Doubeleive said:

the ambient air temp will update after 5 miles of driving, particularly if you are unplugging and messing with it, go drive it at least 5 miles and check again
if you suspect it is faulty, replace it they do get brittle and break easily from being exposed to the elements

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that's the thing, I didn't touch the actual ambient Air temp sensor thats behind the grill. I only unplugged the maf plug and plugged it back in. then the ambient temp on the scanner crashed to 14F. which is a very odd. default. it is slowly coming back thou. it was up to 21deg by the time I got home from work, way more than 5 miles thou.

this is scanner/tech 2 ambient Air temp, not the actual ambient Air temp displayed on the hvac display. that one actually follows the behind the grill sensors. I tested tested that yesterday.

Doubeleive said:

got my most recent oil analysis back, I think the last one they handed me a sample from someone elses vehicle because they said it looked like a 6000 mile oil change and the viscosity was off.
hopefully this means my cam is probably ok
View attachment 431689

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Blackstone sells a nice little hand pump that goes down the dip stick to get a sample. we have one at work, it might be worth while if you're not sure the guys at the shop are doing it right. it really show be taken while up to temp and from mid drain.

eaiser to just shut it off and pump out an ounce at home.

Doubeleive said:

WHICH ONE HAS MORE AIR FLOW?
View attachment 431681View attachment 431682

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I think there's more than just the surface area of the holes involved in the match when air flow modeling is involved. something like the faster air flow, the more it can shroud itself.

something I read years about about a 2 valve head vs a 4 valve head. the 2 smaller valves have much more surface area for flow at lower speeds and lifts, but once the air speed gets up for high rpm, the center of the valves the air flow shrouds itself and one large valve can flow just as much air.

they had graphs and all to show it on a flow bench. not that I can say they were telling the truth or not. I have a 4 valve engine that shifts at 14k. but just what I read. I can imagine at high speeds, say 70mph the small hole grill flowing much less than the wider slats. at least in my head. especially if the slat angle is correct where the small hole grill lays back more, the slates form a air dam on the way up and over the hood.

j91z28d1 said:

Blackstone sells a nice little hand pump that goes down the dip stick to get a sample. we have one at work, it might be worth while if you're not sure the guys at the shop are doing it right. it really show be taken while up to temp and from mid drain.

eaiser to just shut it off and pump out an ounce at home.

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Or install a Fumoto valve and connect a short hose to the oil sample container and fill it, close the valve.
EZPZ

gooffeyguy said:

Why a cardboard funnel? You don't drive down the road with a cardboard funnel taped to the front of the truck do you?

Simulate driving down the highway.
Box fan set to same speed during both tests. Place grill like a foot away during each test and take reading like a foot behind the grill.

Click to expand...

j91z28d1 said:

I think there's more than just the surface area of the holes involved in the match when air flow modeling is involved. something like the faster air flow, the more it can shroud itself.

something I read years about about a 2 valve head vs a 4 valve head. the 2 smaller valves have much more surface area for flow at lower speeds and lifts, but once the air speed gets up for high rpm, the center of the valves the air flow shrouds itself and one large valve can flow just as much air.

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No math needed, except for a ruler (not your wife kind of ruler...). See @Geotrash's post. Apples-to-apples comparison. EZPZ

Grady_Wilson said:

Or install a Fumoto valve and connect a short hose to the oil sample container and fill it, close the valve.
EZPZ

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I got the feeling he wasn't getting under the truck himself.

I honestly wouldn't trust a lube tech to know how to open the valve. they would just unscrew it

gooffeyguy said:

Why a cardboard funnel? You don't drive down the road with a cardboard funnel taped to the front of the truck do you?

Simulate driving down the highway.
Box fan set to same speed during both tests. Place grill like a foot away during each test and take reading like a foot behind the grill.

Click to expand...

because i may be placing the meter in a sweet spot with the open slats, a better test would involve a more controlled environment. If i build a funnel to about a 4" hole then I can get a reading for either one more accurately. I have plenty of cardboard and tape.
I personally think the slots will catch more air but that's just my brain seeing big open slots versus small holes