2004 6.0 NV4500 Tahoe

[Dantheman1540]

Played with the tune and got it to sound more aggressive without making the engine run like it's missing cylinders. It still wants to drop to far after a high rev so I need to figure that out but it's very driveable and WOT safe now.

I went ahead and ordered a Magnaflow 12599 muffler and hopefully I'll have that in soonish.

Heres some questions I asked myself before I started this and the now found answers.

Question: Does the truck feel faster?

Answer: No not really. I do feel that it continues to pull harder after 5500 up to 6500 but I don't believe it is anymore than a 1/10sec or so faster in the 1/4 mile.


Q: Did it lose low end.

A: Feels no difference down low. It still puts you back in your in your seat in 1st and 2nd gear. However my gear ratios are similar to the NNBS 6 speed guys so 4l60 guys you would probably notice it sluggish off the line.

Q: Any other benefits?

A: The valve train is considerably quieter. Could have been a minor exhaust leak that is fixed or possibly dual valve springs and the CHE trunion upgrade make for less noise.

Q: What would I do different?

A: Given more time I would have gotten some custom heads or had these sent off for CNC porting. Also would have gotten custom head gasket to raise comp ratio closer to 11-1. It's at 10.4-1 now. Even with those upgrades I doubt it would pickup more than 10% power gains.

Since I like posting terrible videos heres another one where it pathetically dies after a rev

 

[Dantheman1540]

Figured out the my AFR problem was that the sensor must have died when the engine dumped coolant on it. Anyway replaced it and finally got to some actually air and fuel tuning instead of band-aiding it from acting weird by messing with the spark. There were some very odd spots where I suppose this new cam flows better and the tune was off enough to cause a noticable spike in the graph.

Thanks to videos from Goat Rope Garage on youtube I got it straightened out and it's running smooth and steady. Might tackle timing tuning tomorrow and see if I can pick up MOAR POWA!
Also I wasn't paying attention on one pull and hit the limiter at 6500, subsequently I nearly browned my trousers. Thinking about bumping it to 6800 so I can hit 60 before I have to shift because the 2-3 shift is slow and kills my 0-60 time.

Here's a link to Goat Rope, if you have HPtuners and don't watch his videos your wrong.

 

[Dantheman1540]

Alright heres some new exhaust videos. I replaced the Flopro 2500 with a Magnaflow 12599 and wow it is seriously loud now. Both mufflers are dual 3"in and dual 3"out and the case size is nearly the same, the Flopro is just a tad wider.

First video is just a startup idle and rev

Second video is getting on it from 1st-2-3

 

[randeez]

what kinda gas you got in that thing?

whats with the knock?

 

[iamdub]

Ahh... That familiar NV whine!

Is it too loud for you inside?

 

[Dantheman1540]

what kinda gas you got in that thing?

whats with the knock?

Pump 93 for life. I don't notice any knock myself maybe its the camera or your hearing the "Wonderful NV4500 noises".

However at that time I was still on MAF only. Spark table isn't showing it pulling timing anywhere but maybe I'm wrong. Im knee deep in SD tuning now then Ill start on the spark table.

Ahh... That familiar NV whine!

Is it too loud for you inside?

The trans really isn't as loud as the video made it seem, my phone was sitting inches from the shifter so I think it made it worse. But they do make noise lol. The exhaust is just really loud anytime above 2k even at say 25% throttle its just obnoxious. My GF hasn't complained yet but I'm sure she will if we have a road trip with a trailer. I'm gonna have to see if there is any room to add resonators or not and I'll just go from there. I do feel as though it picked up some power with the muffler swap. I know that sounds dumb but it feel like more of a gain with the muffler swap than the cam lol.

 

[Dantheman1540]

I have never touched the VE tables myself and I suppose the PO never did either because holy crap it was running rich on SD. Unless I'm reading this wrong.

 

[randeez]

that KR

def a little rich, you really need to turn off the maf, ltft, run it in open loop, etc to make sure there is nothing else adding to the fueling.

 

[Dantheman1540]

that KR

View attachment 258747

Oh dang you are right. I wasn't even looking at any of that when I screen shot it. I think that was my second run when MAF tuning and the first time I had run it that high. It should be smoothed out now, I will have to log and see tomorrow now that I think I have it straightened out and back to running the MAF and MAP.

I really appreciate the help because I am far from being a pro at this lol.

 

[randeez]

setup an error histo for the maf also

nevermind just noticed it up on the corner, you can adjust the VE table with it that far off. i would just cut like 10% out of the entire table or something (multiply entire table by .90) it will swing pretty far with everything else effecting fueling

 

[Dantheman1540]

setup an error histo for the maf also

nevermind just noticed it up on the corner, you can adjust the VE table with it that far off. i would just cut like 10% out of the entire table or something (multiply entire table by .90) it will swing pretty far with everything else effecting fueling

I took a log and instead of paste special half, I pasted entire and it got me much closer. Then 2 more logs and adjustments using paste special half and besides a few fliers everything is within 3-4.5%. However I've been researching more on SD tuning and I think I'm going to spend more time dialing it in. There are a lot of cells I'm not populating in my short runs and I want to get it right before I touch timing.

 

[randeez]

yea theres always cells that you need to go in and smooth out by hand, i'll do hour+ drives and just try to get a bit of steady data points and then in the graphs tab set it to average 50+ (ive set some to over 250 hits to the cells) points to see what is continuously being corrected. i dont use the interpolate that often i'll usually just verify what points were rised/lowered and work the graph in by hand.

i forget how small the older VE tables are.

gen4 with sd patch

 

[Dantheman1540]

yea theres always cells that you need to go in and smooth out by hand, i'll do hour+ drives and just try to get a bit of steady data points and then in the graphs tab set it to average 50+ (ive set some to over 250 hits to the cells) points to see what is continuously being corrected. i dont use the interpolate that often i'll usually just verify what points were rised/lowered and work the graph in by hand.

i forget how small the older VE tables are.

Gen 3 has its perks haha. Hand massaging it is kinda time consuming going back and forth from the scanner to the VE table. I need more experience but this is fun, makes me feel smart.

I'm going to spend a good week or 2 on this tune then I think I found a dyno close by and I'll go get a power number.




YUCK thats way too much!

 

[randeez]

Gen 3 has its perks haha. Hand massaging it is kinda time consuming going back and forth from the scanner to the VE table. I need more experience but this is fun, makes me feel smart.

I'm going to spend a good week or 2 on this tune then I think I found a dyno close by and I'll go get a power number.




YUCK thats way too much!

i dont know about fun, but its nice not to have to rely on anyone else to do it!

i will usually multiply % (full or 1/2) and then open the VE table up in the 3d model and you can just drag the points up and down and visually see the transition between the cells

 

[Dantheman1540]

i dont know about fun, but its nice not to have to rely on anyone else to do it!

i will usually multiply % (full or 1/2) and then open the VE table up in the 3d model and you can just drag the points up and down and visually see the transition between the cells

Being self sufficient is satisfying although having Atomic do everything and feeling confident that he knows wtf he is doing is also nice. I never feared beating the old 4.8 at 17psi. Its longevity was probably due to the fact it only had 17* of timing on the base map and more pulled as IAT climbed.



Well just dug through my parts stash and I think I found my next step for exhaust. Vibrant resonators in the very back behind the axle and the Amazon special tips welded directly to them. Those vibrant resonators are works of art and I'm impressed the Amazon tips look right at home behind them.

 

[Tonyrodz]

Being self sufficient is satisfying although having Atomic do everything and feeling confident that he knows wtf he is doing is also nice. I never feared beating the old 4.8 at 17psi. Its longevity was probably due to the fact it only had 17* of timing on the base map and more pulled as IAT climbed.



Well just dug through my parts stash and I think I found my next step for exhaust. Vibrant resonators in the very back behind the axle and the Amazon special tips welded directly to them. Those vibrant resonators are works of art and I'm impressed the Amazon tips look right at home behind them. View attachment 258760 View attachment 258761

They look like they were made to compliment each other.

 

[Dantheman1540]

They look like they were made to compliment each other.

Thanks, I love the look of polished stainless exhaust. The Magnaflow I just put on looked good but its nothing compared to the vibrant stuff they are the *******. I like the look of these resonators with the tips but the neck down between the resonator and the tip kinda looks silly and I'm worried it wont quiet it enough. I'm trying to talk myself into buying 2 of these, and hanging them off the back just like I would the others.

Its a Vibrant 1062 3"inlet and a built in 4" tip. Almost looks like a fart can if it was just one on a honda but I think 2 welded together would look cool and should knock the sound down while still being straight through.

https://vibrantperformance.com/cata...id=18&osCsid=326b50fb84cf0e4f340b58652c709fa0

 

[Dantheman1540]

So to put some science and shit behind this muffler debacle here is a decibel readout from my commute. As I make changes I will retest and see how effective stuff is.

 

[Rocket Man]

Being self sufficient is satisfying although having Atomic do everything and feeling confident that he knows wtf he is doing is also nice. I never feared beating the old 4.8 at 17psi. Its longevity was probably due to the fact it only had 17* of timing on the base map and more pulled as IAT climbed.



Well just dug through my parts stash and I think I found my next step for exhaust. Vibrant resonators in the very back behind the axle and the Amazon special tips welded directly to them. Those vibrant resonators are works of art and I'm impressed the Amazon tips look right at home behind them. View attachment 258760 View attachment 258761

That’s some good luck there. You gonna have room for all that?

 

[Dantheman1540]

That’s some good luck there. You gonna have room for all that?

I deleted my spare tire and I'm gonna go in and remove the rest of the bracketry up under there so I have a ton of space behind the axle. Making it look nice is the hard part. I'm gonna try to cram some ultra quiets before the muffler first and the tip/resonator combo will be step 2.

Whats your decibel in the beast?