99 Denali

[Snowbound]

I don't see anywhere to post a build thread and I have some drivetrain upgrades coming so I'm gonna go thru what I've got, what I've done and what's coming here. If there is a better place to post this, mods feel free to move it or let me know where I should move it. Thanks in advance.

I've always been a GM guy. I acquired this 99 Denali back in 2010 when we as a family were planning on going to Branson MO and I refused to pay $600 to rent a suburban for the week. I came across this one in autotrader from a dealer about an hour north of me.

It needed some love. The drivers side mirror was broke. I took the mirror off my 97 K1500 since I had tow mirrors for it. The entire front end needed to be gone thru. It was loose. It needed tires and to be cleaned inside and out really bad. So I picked up some paint and painted mirror to match. Then I replaced everything on the front end. Tie rods inner and outer, adjusting sleeves, pitman arm, idler arm, ball joints upper and lower, sway bar end links, CV shafts, hub bearings and powerstop brakes.

Then did a full tune up, oil change, diff fluids, t-case oil, coolant flush and dual red top batteries. Then I pulled the factory radio and installed a flip out DVD player so the kids could watch movies while we drive from Chicago to Branson.

Truck did very well on the trip. AC had a slow leak and I had to put 3 cans of freon in it the week we were down there to keep us cool.

 

[Snowbound]

After we made our trip I drove this thing for a few weeks then got lazy and had Walmart change my oil. I was using Mobile1 and they had a sale for cheaper than I could change it for so I had them change it while I did my grocery shopping. I didn't notice anything that day but the next day when I started it for work it sounded strange when it fired. Only way I can describe it is like a pulley rattle or like something barely touched the fan. It was faint and didn't drive any different but I had it in the back of my head for the next 2 days. That third day I loaded up the truck for a trip up north. Heading down the highway we had AC going but my window was down a little. Every time I got near a concrete barrier wall in the left lane I could hear a noise. At first I thought it was the truck next to us but after we passed it I still heard it. Seemed like every time I'd turn the radio down and listen we weren't next to a barrier so I didn't hear anything. Made it into Wisconsin and decided I was going to check it out at the rest area just over the border. On the exit ramp I let off the throttle and the engine died. Pulled into parking lot and tried to start it back up but it would only start with some throttle like it was under a heavy load. My mind was racing and I'm thinking maybe that noise I heard three days prior was a pulley so I pulled the belt and tried to start. Same thing. Threw the belt back on and said we're going to turn around and see how far we can make it home before it grenades, I knew it was gonna. Made it 8 miles back into Illinois and BOOM!! She went. Blew a rod right thru the block and oil pan. Called for a tow and a cab. An hour later we're in Rockford with the truck on a side street and a buddy coming to get us. Made it home, grabbed truck and a trailer and drove back and towed Denali back home. It wasn't a big deal. I knew I wasn't going to use the 350 that was in my 97 so I pulled that and threw it in Denali, I was back up and running the next weekend.

By this time my temp plates were about to expire and I never received my plates and title. I called the dealer and he said call back on Friday because that's when they should have it. It was Wednesday. Friday I called back and got no answer. I drove to the dealership and son of a *****, they were out of business. I had to go to the Secretary of State Police and file a report. They gave me another temp plate and told me I wasn't the first person that dealer did this to. Long story short, the dealer never had the title to this vehicle. There was a lien on the title. The SSP prosecuted the business and got me the title and plates. I was also reimbursed $800 from the court. I was trying to get my money back and I would have thrown the blown engine back in it. But whatever, everything was worked out.

3 months later I went back up north for a snowmobiling trip and the next morning I drove the truck 40 miles to town for groceries and as I was getting into town I lost all oil pressure. Parked the truck in the parking lot, checked the oil and it was good. Not low or dirty or anything. After we got groceries I started the truck and oil pressure was back. Drove home 40 miles and half way lost pressure again. I would shut engine off and coast as far as I could then restart and get to speed then do it again. Made it back to the house that way and called my brother in law to come up 6 hrs and get us. Left the truck there all winter and in the spring hooked up a mechanical oil pressure gauge and checked pressure, same thing. Once warm it lost pressure. Brought it back home on a trailer. Got a lot of slack for this Denali from my dad telling me my GM product couldn't make the trip up north. So now I made up my mind to build an engine for it. And this is where it starts to get good.

 

[Snowbound]

Right now the truck starts and runs. No oil pressure once it warms up but at least I can move it around. So I didn't want to pull engine until I got the new one done. I had a 350 4 bolt main sitting in garage from an old square body dump truck I bought for the axles. Brought that to the machine shop and had it dipped, magna-fluxed, bored, cam bearings replaced, lined bored, decked, boss' drilled and tapped for roller cam, clearanced for stroker crank and freeze plugs replaced.

Next I started ordering parts. **** steel crank, H-beam rods,speed pro Pistons with Teflon coated skirts, all ARP hardware and had the rotating assembly balanced.

And yes, incase your wondering, I did build this engine in my living room.

 

[Snowbound]

First I mic'd all my journals and checked clearances, installed crank, pistons and rods, torqued and checked side clearances.

Called Comp Cams and talked to one of their techs and told them what I was building and what it was going in and they gave me their opinion on which cam to use. After about half hour on the phone I decided on a custom grind cam, the cost was less than $50 from an off the shelf unit. I was limited by computer on my choices but we compromised. That arrived 9 days later and went in. Degree'd the cam and installed timing chain, a gear drive would interfere with the knock sensors so I couldn't use it, installed new timing cover with hole for crank sensor.

Always hated the plastic distributors in these Vortec engines. I found an aluminum unit that came complete.

Next came the heads. Went down to the local speed shop and talked to the owner. He called Edelbrock and we discussed which set of heads to use. He had a set of 190's that another guy ordered but never picked up, could have got a good deal on them, but after discussing what I have we concluded that the 170's would be a better option due to the fuel system on the Vortec.

 

[Snowbound]

As you can see in the above pic, I decided to go with Comp Cams gold rockers in a 1.5 ratio.

The pushrods may have worked in stock length but I installed my pushrod length gauge and decided to go with ons that were .020" longer. Gave me a better pattern on the valve stem. Kinda hard to tell from pic but the extra length centered the roller on the valve stem better than stock through its cycle.

For injectors I ditched the sequential fuel injection and upgraded to multiport which moved the injectors down into intake runners as oppose to the poppet style that always seemed to carbon up and fail.

 

[Snowbound]

First road block was with the rockers. I couldn't use the center bolt valve covers because they aren't tall enough to clear. Sounds simple enough, right? Yeah, I found a set of Edelbrock covers and luckily the heads have provisions for center bolt or perimeter bolt. Same with intake, there's holes for vortec manifold and regular. Makes it nice for if I decide to go with a different intake. The real issue is with the serpentine brackets. The AC bracket hangs over the valve cover on the drivers side. So my new valve covers fit over the rockers but not under the bracket.

my cure was to remove the rear outside mounting hole.

 

[Snowbound]

Now that the engine is almost complete, it was time to remove the old engine, originally from my 97.

Now that that's out of the way, I can finally do what I wanted to do the first time I replaced the engine, clean it and paint it.

 

[Snowbound]

I cleaned up a lot of the wiring and spent a good 5 hrs washing, wire brushing and wiping down the frame.

Fresh coat of POR15.

Looks so much better after it cures.

 

[Snowbound]

I pulled the clam shell engine mounts apart and found this.

Time for some new poly mounts.

Before I drop engine I had to address the trans. It's a 4L60E, not my first choice but if I wanted it to have any chance in hell to survive, I needed to upgrade. Fist I replaced the trans lines and added a cooler. Next I dropped the pan and installed a shift improver kit and changed the filter. Friend of mine gave me a name and number to a company in Cali that builds torque convertors. The TCI unit I was looking at was very expensive compared to what I paid to have one built. Again, I discussed with this guy on the phone what I have done and what vehicle it goes in and we agreed that a 2300 stall would be good for my application. When that came in I put some fresh ATF in it and threw it on the trans. Ended up going with Mobil1 synthetic ATF. Sorry, no pics. Photobucket dropped them somehow.

 

[Snowbound]

Time to drop this baby in.

Still running into an interference with them valve covers. The AC compressor would not fit down onto the bracket. Time to improvise again. What I did was make a few spacers and got longer bolts so the AC was 3/4in above the bracket. Had to go to a longer belt to make it work but it works, that's all that matters.

 

[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.