99 Denali

[Snowbound]

Now that it's in, I need to move air in and out of it. I replaced throttle body with one that is bored a lot larger. I forget the CFM but I can look it up in my folder. For intake I went to a Volant cold air system. Prob the best on the market. It's a true cold air intake, as the box is sealed and it gets its air source from inside fender.





And of course, wouldn't be complete unless it cost me
another $300 to make the system work. The Mass Air Flow sensor does no good in stock form. Has to be a wider range sensor to pick up the larger amount of air that can suck through this intake.

For exhaust I started with a larger crossover pipe leading into these high flow cats.



I made a flange that bolts up to a Flowmaster cat back kit that's 2.5 into singl 3.

 

[Snowbound]

So now I have everything hooked up, adjusted and oil and ATF topped off. I'm almost ready to start but first I need to flash computer for the changes. I bought a Superchips Vivid Bluetooth programmer. This little box plugs into the OBDII port and you download the Vivid app and set up your parameters. Only problem is its for Android and I don't have an Android devise. Damn it!! Off to Wally World and buy a cheap tablet so I can download my programs. $200 later I set up my program and I think I'm ready to start. Just need to add coolant. Start putting in my Dexcool and I start to hear it hit the floor. Where the hell is that coming from? Start looking around and I can't see where exactly but looks like it's coming from the passenger side of the water pump. Shroud comes off, belt off, alternator off and I remove the accessory bracket from that side. Appears I overlooked a small coolant passage where the old style water pumps cover. I feel the hole, can't really see it. I stick a bolt in it to stop anymore coolant from leaking.





Ok, so let's go over to the Vortec engine and see what I missing. This one has a freeze plug in that hole.



Or maybe it's a blind hole. Either way, I need to plug that SOB.



I ended up being able to tap the hole so I could get a plug in there.





Put everything back together and let's try this again. Fill up coolant, no leaks!! That's a good sign. Check everything over once more. Everything is new. Oil lines, trans lines, both coolers, oil filter adapter, radiator, hoses, water pump, t-stats, everything!! I shouldn't have any issues firing this thing. I've primed the oil pump, I think I'm ready. I don't have the valve covers on at this time, or at least the drivers side so I can check I'm getting oil to the top of the head. Turn the key on, fuel pump primes, one gentle tap of the starter and BAM!! She fires right off. Check the correlation between cam and crank sensors with my scan tool and I'm close, 2*+. Have good oil pressure on gauge, 60PSI. Look under hood and nothing at rockers. Just the assembly lube. Shut her down!! Looking at everything, I think that's when I pulled the passenger side valve cover to see if I can see anything over there. Nothing!!?? I start it back up, rev it up twice by hand while watching, nothing!! I let it run for a good 3 minutes and still no oil coming from pushrods. I'm starting to get pissed. I call machine shop and ask him what cam bearings they put in my engine. He tells me he uses the same ones on every engine he builds. I asked if there's any way he didn't line up the oil passage with the bearing. He says no way, they are grooved all the way around the back side of the bearing, it should get pressure. He thinks something is wrong with my new high volume oil pump. So I get off the phone, I just start cleaning up contemplating my next step. I decide to try it again. Start it up, runs for 2 minutes, nothing. I'm pissed. Start it up, get mad and start revving 'er up to 2k RPM and BAM!! I have oil!!! I soaked the shit out of them lifters and even pumped them up while bathed in oil. Don't know why it took so long but it did. Now she's alive and I get to baby it for a few hundred miles and then change the oil and get that zinc oil out of it

 

[Snowbound]

Drove this thing for about 3 weeks and kept getting a code for lean bank one and two. Pulled the plugs and it did appear to be running lean. Plugs were more white than tan in color. I did notice that it seemed like the throttle return spring was sticking on this new throttle body. Started looking at it and by hand with engine off it's smooth and there's no sticking at all. Start the engine and breaking the throttle body seal its pretty hard then snaps open. So I'll just have to deal with that issue. It's because this engine is sucking so much air, I noticed with my scan tool that the idle air control motor is more than 80% open while idling. As far as the lean mixture, I need to give this thing more fuel. Played with the tuner, didn't make much difference. With fuel pressure gauge it idles at 60PSI but would drop to 38-42 PSI with throttle but that's with no load. Time to upgrade the pump. I decided to buy a complete sending unit to make the swap easier and quicker. I couldn't find a performance pump with sending unit so I bought a cheap sending unit with pump and then bought a Delphi performance pump. (Can't remember at this time what the GPM is) I got my parts and disassembled sending unit and removed cheap pump.





The new performance pump wouldn't fit in the plastic cup that the other pump was in. This one is fatter and has a different plug.



Wired new pump in and made it fit.





All back together and ready for install.

 

[Snowbound]

Fuel pump went in no issue. I went ahead and replaced the pressure and return lines with some 3/8" hose to get better flow. Also filter got replaced with a high flow unit. It's only a 30 micron so that needs to be tightened up here soon.

 

[Snowbound]

Had a brake line break on rear by fuel tank. Pulled line and replaced. Also did new master off an 04 Tahoe. Master made a big difference.

 

[Snowbound]

Now upgrades that are getting done is
14 bolt semi floater swap with 4.56 gears
4L80E swap to get rid of the 4L60E
Lowering kit, thinking 4in would be good
New tires in stock size
0411 PCM swap

 

[#1taho]

Oh this is a good build thread. I am subbed and anxiously waiting for more

 

[ajaxnxs]

Great build!!!

 

[Tonyrodz]

I'm loving this build!! Ever figure out why the 2nd motor was losing oil pressure? Rig looks FANTASTIC!! Huge thumbs up! Anxiously waiting for more updates.

 

[Snowbound]

Thanks guys.
Tonyrodz- I think it was an oil pump issue. I was gonna pull it apart and see if the pump gears are worn or what but instead it's still sitting in my garage and I've slowly been stealing parts off it for guys that need something. That engine only had 140k miles on it but it was hard miles. I plowed with the 97 and beat on 'er in the mud. I suppose it could have been a bearing but the fact that it lost pressure only when it gets warm leads me to believe pump. Oil warms and thins and gap must be too great and drops off.