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

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iamdub

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I'd be worried about road debris catching the wires, but I guess they could be zip tied up close.

I think those wires were just drawn for illustrative purposes. That's the location for the Gen4 knock sensors, except they're screwed directly into the block. The wires are routed and attached close to the block with clips, and the cross member protects them, too.
 

Sam Harris

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Thanks brother. It's been a while since I updated it!

Re: LSA: Nice.. I think 112 will be good then..

Stock / Stainless valves are good.. Awesome..

Yes, I can order a number of different options, or build to suit. They do have a handy compression calculator, but it's tough being clueless.. I know I can use a thinner head gasket to bump compression a bit, but I don't know if I can really get all this figured out until some of these things are in place.. Thanks much for the tip on the Fel-pro..!

The heads are new -cast, and this is one of the things I'm trying to decide on. (though they do have a package with customer supplied heads as well) As-cast vs aftermarket casting? Not sure what that means. I think a ported head would be the best option... Here's one that I thought might me a good fit: https://www.texas-speed.com/p-8013-prc-15-degree-220cc-cnc-cathedral-heads-cam-package.aspx however, I also don't know what would be a good choice for cc volume.. 220 all the way up to 247cc..?

Timing chain: I figure between your and Mark's recommendations, I'll probably go with a single roller Cloyes.. Of course that still leaves Z06 or C5R. I guess the Z06 will do fine there.. less expensive..

Melling HV is the plan. I will do this..

Pretty sure the TB is a 3-bolt. I removed it about 18 months ago, but don't remember. lol.. It is a DBW, and since I have Flex, I think I should be good there - hopefully.
Do I need cooler plugs..? If so, I think I'll need to look into a LSA, to justify the plugs.. :challenge:

ETA: Gears are 3.73..
Ok, today, ordered a few things.. Got the level 3 Invincible trans 4L60E from Performabuilt, along with a 10.5" triple disc 2800 stall torque Converter.. Heads are the PRC "As cast" 225cc kit from Texas Speed, with stainless valves, new dual springs, titanium retainers, 212/218, .600"/.600", 112 LSA Cam, chromoly pushrods, and head gaskets (stock thickness), ARP balancer bolt, crank seal, cam bolts, cam retainer plate and bolts..

I've decided to put off the intake upgrade, since I still have more research to do, and seems debatable how much difference that will have anyway. I may save this part for the 6.0 build down the road.. ;)

Still need to order the oil pump, timing chain kit, head bolts, water pump & gasket, oil pan gasket, front cover gasket, valve cover gaskets, valley cover gasket, knock sensors and harnesses, lifters, and trays..?

I have the rear cover set, which includes the rear main..
Trunnion upgrade arrived today, but does not have the install kit. Should be able to make do without that.

looking for feedback regarding the lifters. I don't want the LS7, since I see those may need machining, and I want to avoid this.
I have read that the only worthwhile lifter trays are OEM, but not sure if that only applies to the Gen 4 motors, or if I should order (or even need them) for the Gen 3?
Looking at these lifters, and suspect they should be fine: https://briantooleyracing.com/comp-cams-lifter-set-high-energy-gen-3-4-ls-cc850m-16.html
I don't see any need for the tie-bar style with the planned mods, but if they are good insurance, I'm also open to that.

Any other thoughts or recommendations are more than welcome!

And, I do think it's time to make a build thread... I'll have to take a week or so to do that. lol

Pic for attention:
 

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Rocket Man

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Ok, today, ordered a few things.. Got the level 3 Invincible trans 4L60E from Performabuilt, along with a 10.5" triple disc 2800 stall torque Converter.. Heads are the PRC "As cast" 225cc kit from Texas Speed, with stainless valves, new dual springs, titanium retainers, 212/218, .600"/.600", 112 LSA Cam, chromoly pushrods, and head gaskets (stock thickness), ARP balancer bolt, crank seal, cam bolts, cam retainer plate and bolts..

I've decided to put off the intake upgrade, since I still have more research to do, and seems debatable how much difference that will have anyway. I may save this part for the 6.0 build down the road.. ;)

Still need to order the oil pump, timing chain kit, head bolts, water pump & gasket, oil pan gasket, front cover gasket, valve cover gaskets, valley cover gasket, knock sensors and harnesses, lifters, and trays..?

I have the rear cover set, which includes the rear main..
Trunnion upgrade arrived today, but does not have the install kit. Should be able to make do without that.

looking for feedback regarding the lifters. I don't want the LS7, since I see those may need machining, and I want to avoid this.
I have read that the only worthwhile lifter trays are OEM, but not sure if that only applies to the Gen 4 motors, or if I should order (or even need them) for the Gen 3?
Looking at these lifters, and suspect they should be fine: https://briantooleyracing.com/comp-cams-lifter-set-high-energy-gen-3-4-ls-cc850m-16.html
I don't see any need for the tie-bar style with the planned mods, but if they are good insurance, I'm also open to that.

Any other thoughts or recommendations are more than welcome!

And, I do think it's time to make a build thread... I'll have to take a week or so to do that. lol

Pic for attention:
So much fun stuff.
Edit: you’re gonna love how that Performabuilt shifts.:)
 
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mattbta

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looking for feedback regarding the lifters. I don't want the LS7, since I see those may need machining, and I want to avoid this.
I have read that the only worthwhile lifter trays are OEM, but not sure if that only applies to the Gen 4 motors, or if I should order (or even need them) for the Gen 3?
Looking at these lifters, and suspect they should be fine: https://briantooleyracing.com/comp-cams-lifter-set-high-energy-gen-3-4-ls-cc850m-16.html
I don't see any need for the tie-bar style with the planned mods, but if they are good insurance, I'm also open to that.
I used the Morel drop-in lifters now part # 7717 (mine are 6504) when I replaced my heads. Been happy so far. Absolutely get new OEM trays and I suspect you will want a pushrod length checker to get appropriate pre-load with your other valvetrain mods.
 

Sam Harris

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I used the Morel drop-in lifters now part # 7717 (mine are 6504) when I replaced my heads. Been happy so far. Absolutely get new OEM trays and I suspect you will want a pushrod length checker to get appropriate pre-load with your other valvetrain mods.
Thank you..!
 

Walchit

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Ok, today, ordered a few things.. Got the level 3 Invincible trans 4L60E from Performabuilt, along with a 10.5" triple disc 2800 stall torque Converter.. Heads are the PRC "As cast" 225cc kit from Texas Speed, with stainless valves, new dual springs, titanium retainers, 212/218, .600"/.600", 112 LSA Cam, chromoly pushrods, and head gaskets (stock thickness), ARP balancer bolt, crank seal, cam bolts, cam retainer plate and bolts..

I've decided to put off the intake upgrade, since I still have more research to do, and seems debatable how much difference that will have anyway. I may save this part for the 6.0 build down the road.. ;)

Still need to order the oil pump, timing chain kit, head bolts, water pump & gasket, oil pan gasket, front cover gasket, valve cover gaskets, valley cover gasket, knock sensors and harnesses, lifters, and trays..?

I have the rear cover set, which includes the rear main..
Trunnion upgrade arrived today, but does not have the install kit. Should be able to make do without that.

looking for feedback regarding the lifters. I don't want the LS7, since I see those may need machining, and I want to avoid this.
I have read that the only worthwhile lifter trays are OEM, but not sure if that only applies to the Gen 4 motors, or if I should order (or even need them) for the Gen 3?
Looking at these lifters, and suspect they should be fine: https://briantooleyracing.com/comp-cams-lifter-set-high-energy-gen-3-4-ls-cc850m-16.html
I don't see any need for the tie-bar style with the planned mods, but if they are good insurance, I'm also open to that.

Any other thoughts or recommendations are more than welcome!

And, I do think it's time to make a build thread... I'll have to take a week or so to do that. lol

Pic for attention:


I got the $159 lifters from btr.
They said their lifter trays were the same as OEM so I went ahead and took the 15 dollar gamble. I'm kinda wishing I would have got OEM now that I typed that lol. I wanted tie-bar lifters, but they are way out of my price range.
I'm gonna order a trunion upgrade, and I'm thinking about 4.8 pistons. But I have gen3 rods so I'm not sure I want to go through the trouble. And the crankshaft balancing, lol
 
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Sam Harris

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I got the $159 lifters from btr.
They said their lifter trays were the same as OEM so I went ahead and took the 15 dollar gamble. I'm kinda wishing I would have got OEM now that I typed that lol. I wanted tie-bat lifters, but they are way out of my price range.
I'm gonna order a trunion upgrade, and I'm thinking about 4.8 pistons. But I have gen3 rods so I'm not sure I want to go through the trouble. And the crankshaft balancing, lol
Thanks for the feedback. I’m purposely avoiding the LS7 lifters though, since they seem to require some machining. I believe they’re slightly larger diameter. (May or may not require machining.. perhaps with 220k on my motor, it would be sufficiently wallered out (“like a $2 streetwalker”) to accommodate the LS7 style. :mwah1:)
 

Scottydoggs

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today i was blessed with a rain day and some 45 degree weather, so i decided last night at some point today im doing a tune up. had the truck for 4 years now bought plugs and wires right after i bought it, it ran ok so i blew it off for years. with gas prices going up i figured no better time then now, who knows maybe it will do better.

got to say ive seen posts of ppl raggin on plug 8. my last two trucks i had no issues getting any of the plugs out, but 8 on a tahoe, wtf man. wish i owned a 1 inch extension, had to do the old wrench on the socket deal, same deal for plug 5, damn steering shaft was in the way. needless to say, plug 8 and 5 went back in first lol

lucky for me ive got one of them battery powered ratchets, broke 8 free with a wrench, stuck the power ratchet down there and backed it out in like 2 seconds. also got my hand torn up when it came back up. 5 cuts, that ac pan there sucks for sure.

did notice the part number on the plugs that came out were different from the ones i put in there. hoping the new right ones add something somewhere. plugs had clearly been changed once upon a time. could tell by the thin red crappy looking plug wires.
 

Rocket Man

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today i was blessed with a rain day and some 45 degree weather, so i decided last night at some point today im doing a tune up. had the truck for 4 years now bought plugs and wires right after i bought it, it ran ok so i blew it off for years. with gas prices going up i figured no better time then now, who knows maybe it will do better.

got to say ive seen posts of ppl raggin on plug 8. my last two trucks i had no issues getting any of the plugs out, but 8 on a tahoe, wtf man. wish i owned a 1 inch extension, had to do the old wrench on the socket deal, same deal for plug 5, damn steering shaft was in the way. needless to say, plug 8 and 5 went back in first lol

lucky for me ive got one of them battery powered ratchets, broke 8 free with a wrench, stuck the power ratchet down there and backed it out in like 2 seconds. also got my hand torn up when it came back up. 5 cuts, that ac pan there sucks for sure.

did notice the part number on the plugs that came out were different from the ones i put in there. hoping the new right ones add something somewhere. plugs had clearly been changed once upon a time. could tell by the thin red crappy looking plug wires.
If you put a regular depth socket on the plug socket instead of a wrench it’s the perfect length for a ratchet.
 

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Walchit

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Thanks for the feedback. I’m purposely avoiding the LS7 lifters though, since they seem to require some machining. I believe they’re slightly larger diameter. (May or may not require machining.. perhaps with 220k on my motor, it would be sufficiently wallered out (“like a $2 streetwalker”) to accommodate the LS7 style. :mwah1:)

This one has 294k, so hopefully it fixes the hotdog down the hallway situation.
I didn't know they were bigger, I'm gonna have to get the caliper out and check. Whatever I looked at said they would work, so hopefully I don't wind up with a set of lifters for sale...
 

AJ Lerway

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I debated again today if I should spend the $1200 to replace the ABS ECBM due to the random Check Engine light or try to sneak in another State Inspection when the light is not on. I've been successful for 4 years now but I'm about to gift the Tahoe to my son. Can't decide..........

Other than that, I added a Steelie Windshield mount... happy with it:

Nite Ize Original Steelie Orbiter Windshield Mount Kit - Low Profile Magnetic Car Windshield Mount for Smartphones​

 

Walchit

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Drained and refilled the transfer case today.Fluid was greenish brown that came out.Nice blue went in.
I should probably change mine.
I debated again today if I should spend the $1200 to replace the ABS ECBM due to the random Check Engine light or try to sneak in another State Inspection when the light is not on. I've been successful for 4 years now but I'm about to gift the Tahoe to my son. Can't decide..........

Other than that, I added a Steelie Windshield mount... happy with it:

Nite Ize Original Steelie Orbiter Windshield Mount Kit - Low Profile Magnetic Car Windshield Mount for Smartphones​


I was gonna try to reflow the solder on mine. It moved down to number 2 on the list though.
 

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