2004 6.0 NV4500 Tahoe

[Dantheman1540]

You don't say! lol
I might could've gotten away with .041" but I wussed out and went with .045". At that time, I didn't know Fel-Pro was an option. Dropped the coin on the Cometics. If I couldn't save the scratch, the least I could do is pass what I learned after the fact.




I used a dial indicator and magnetic mount from Hazard Frought. It's really not all that involved. There are plenty of YT vids. Basically, you get the piston flush with the deck, set the DI on it and zero it out then raise the piston to find the maximum. You measure from different points and with the piston rocked both ways, averaging the two figures. Keep a notebook handy. Don't be surprised if the four corner cylinders show shorter heights (less out the hole) than the four center ones. Determine your HG thickness based on the highest piston height.

I'd take the heads to a shop to measure the volume. It's kinda tedious and requires somewhat specialized equipment, so I'd let a shop do it. It shouldn't be much in labor charges- at least, not enough to bother homebrewed methods.

I forgot I actually have the dial indicator setup to do exactly that measurement, I bought it all when I built my first 6.0 and found it just now when scouring my garage for paperwork on those heads.

I’m gonna text my machine shop buddy tomorrow and see if he can sneak me in for a quickie on the chamber size. I was hoping I either had paperwork in the box with them or they etched it on the head but no luck.

Unless it's frozen and the pump can't move it, your oil pressure should be higher when cold.

Straight 15W-40 was unnecessarily thick for my liking and I wanted more than 5W-40, so I mix it 50/50 for 10W-40 since that weight doesn't exist in Rotella T6. Blackstone said my last sample's viscosity was within the range of 10W-40.

It’s strange that it seems so low on cold day starts but it did it last winter as well except even worse with the 15w40 and there was lifter clatter then. Mechanically I can’t think what would cause it unless condensation in the oil froze but it was only below freezing a few hours and I doubt the oil got below 40*.

I will be doing a black stone test this coming change I am very curious about the health of this bottom end and my oil change habits.

 

[Dantheman1540]

You know you love your truck when you start mixing your own oil.

That’s some street chemist sh*t

 

[Rocket Man]

That’s some street chemist sh*t

I knew a “street chemist” or two back in the day.

 

[Dantheman1540]

Alright, heads will be measured this week, I talked to my engine shop connection and he said bring them to the back door and bring a tip. I said I have a big tip for ya .

I think as soon as I know the head chamber volume I will order the .041s and .045s, I doubt the deck height will be more than .008 so one of those two sizes will work and I can return the one I don't use and still get the job done in a weekend. I also ordered a pack of 4" foam pads to soak in Seafoam and lay on the pistons to loosen all the carbon so I can clean them easily.

 

[iamdub]

Alright, heads will be measured this week, I talked to my engine shop connection and he said bring them to the back door and bring a tip. I said I have a big tip for ya .

Since they're just measuring a head, all you need to give 'em is the tip.

I think as soon as I know the head chamber volume I will order the .041s and .045s, I doubt the deck height will be more than .008 so one of those two sizes will work and I can return the one I don't use and still get the job done in a weekend. I also ordered a pack of 4" foam pads to soak in Seafoam and lay on the pistons to loosen all the carbon so I can clean them easily.

View attachment 361502

Never heard of this idea. I like it!

 

[iamdub]

You know you love your truck when you start mixing your own oil.

I'm running low on other points to geek out on!

 

[Dantheman1540]

Since they're just measuring a head, all you need to give 'em is the tip.

Smooth follow up

 

[iamdub]

Smooth follow up

Smooth- just like when you follow up the underside of my hea... Oh, never mind.

 

[pwtr02ss]

Smooth- just like when you follow up the underside of my hea... Oh, never mind.

I see you're passing on my bomb ass instructions

The gift that keeps on giving

 

[Dantheman1540]

Weird occurrence when getting gas today. I stopped at a quarter tank or so (this sender seems to read extra empty early) and when I was filling the handle clicked at 16gallons. I reset my trip every tank so I expected to put 18+ gallons in it at a little over 260miles that tank since I towed a bit and have noticed a MPG drop with the 33s. Anyway it clicked at 16 so I Started filling again and in less then a gallon gas started pouring out just behind the quarter panel! I stopped quickly very embarrassed and drove off after a quick look making sure nothing was about to fall off.

I just got home and laid in the wet grass to further inspect and found everything is tight and in good order. I ran my hand along the fill tube where I couldn’t see and felt no issues. Could the handle of the pump just stuck on forcing gas around the inlet to those little drain holes and out the back as a safety feature to not spray the filler?

Never had this happen before so it kinda freaked me out tbh.

 

[Dantheman1540]

Head chambers are 63cc which is perfect for 10.4:1 with the .041 gaskets.

 

[pwtr02ss]

Head chambers are 63cc which is perfect for 10.4:1 with the .041 gaskets.

They're quick with the head game around your parts

 

[Dantheman1540]

They're quick with the head game around your parts

Back door and $20 gets your head wet quick!


CR seems great but the quench will be tight depending on deck clearance, if the DC is .006 quench is .035 which is on the tight end of being acceptable under 6k according to the summit racing chart. If it's .008 then it's too tight according to the chart.

 

[Rocket Man]

Head chambers are 63cc which is perfect for 10.4:1 with the .041 gaskets.

That’s good head.

 

[Dantheman1540]

I misspoke and subtracted instead of adding the gasket thickness to the deck clearance. Quench should be safe at .045-.049 depending on deck height.

 

[pwtr02ss]

Maths hurt my head too

 

[Dantheman1540]

Maths hurt my head too

I only like the maths with the money signs

 

[pwtr02ss]

I only like the maths with the money signs

Me to buddy, me tooo

Glad you're making progress on this thing. You considered a bigger cam or are you happy where you are? I wish I had gone little bigger with my cam in the avalanche but there again, still stock tune so I'm probably not getting everything out of it. The chop is big enough to be an annoyance but not big enough to get past the "sounds like its missing"...lol. I did the BTR stage 2 truck cam before I had the heads ported. Wish I had taken advantage of that and done a custom grind cam with more lift and a little more duration, tighter lobe separation.

Wondering about some 13 second passes now....

 

[Dantheman1540]

Me to buddy, me tooo

Glad you're making progress on this thing. You considered a bigger cam or are you happy where you are? I wish I had gone little bigger with my cam in the avalanche but there again, still stock tune so I'm probably not getting everything out of it. The chop is big enough to be an annoyance but not big enough that it sounds like its missing...lol. I did the BTR stage 2 truck cam before I had the heads ported. Wish I had taken advantage of that and done a custom grind cam with more lift and a little more duration, tighter lobe separation.

Wondering about some 13 second passes now....

I'm really happy with this cam and I think it's being held back by lack of flow from the 862s. The driveability down low is excellent, I have never once thought this thing needed more low end especially with the trans gear ratios. Mid-range is strong as well but at about 3k it starts to really pull good to about 6,200 where I feel it lose some steam. if these heads only gained power above 5k I'd be okay with that but, I think they will pick up some in the midrange as well. I 100% believe it has a 13.99 in it but the launch and my shifting is the limiting factor. If it was a built 4l60 or 6l80 it would have been at least high 14s.

You seriously need to adjust the tune your probably missing a considerable amount of top-end, especially in the spark table.

 

[pwtr02ss]

You seriously need to adjust the tune your probably missing a considerable amount of top-end, especially in the spark table.

I really do. I try to get focused on learning it, I just have a mental block. Once I think I can't figure something out, I have a real issue getting past that. I also don't wanna ask a million questions and annoy you or Randy