S480/3794 high EGT’s

[Creeker15]

you will gain far more vibrations inside with the solid mounts. the bolted stock mount fixes the issue while inducing more nore vibrations than stock. interior plastic rattles drive me nuts on a daily driver, i wouldnt do them on that kind of setup but its personal preference. Same reason i yanked the poly body mounts out of my truck in a matter of two days because the increase in vibration and noise was terrible.

easy way to tell about the mount is to lift the hood up so you can see the engine from the driver seat, put the truck in 4wd and start to do a boosted launch. make sure no one is in front of you and you have a clear path should something happen with the brakes. watch the engine as you do this and if the mount is bad, you will see the engine jump up 3-4". putting it in reverse and doing the same test will tell you if the pass side mount is bad as well.

if it is bad and you replace it, id really look at the inside of the boot that keeps blowing or just replace it all together. as they blow off, it tears them up internally (sometimes visable, sometimes not) and they start blowing off easier. it shouldnt be blowing as easy as it is now so its most likely a combo of issues like the motor mounts. A new one is a good piece of mind at this point.

as for boost being low or not, thats dependent on tuning (we dont know what mark has in there for tuning on lvl 3) and possibly boost leak. if mark is only commanding a 2k uS on lvl3, 40 psi doesnt sound far off. if hes commanding 2.5k uS, well then 40psi is low. Log your truck at WOT and see what the highest pulse width is on lvl 3 and take note. you can do the same on lvl 5 and it will give us an idea of the size tunes you have. max timing and what the vave position is at would help as well. We are looking for the numbers ONLY at WOT, between 2800-3200rpm, 3rd gear and up, no tire spinning, and no chopping throttle or doing werid stuff. gotta be a clean run.

I’ll try to get that log today. I only have 3 days before the truck goes into storage.
I had a video of pull previously, tune 3 made 41ish (a little over 40) psi and spooled Stupid fast.

And thanks for the knowledge on how they command stuff on the diesel I love learning this stuff!

truck is daily driven right now but won’t be when I get back. I’ll see how the solids do since I already have them. If I hate them I’ll get bolted stocks. I never heard of bolted stocks until now.

 

[Trimox]

Upgrading Engine Mounts

www.duramaxforum.com

Post #30 Unless someone has started selling them they are DIY only. I did mine and a buddies. Just make sure you put the bolts in the right way or they will interfere with remounting. Learned that on the second set.

 

[Creeker15]

you will gain far more vibrations inside with the solid mounts. the bolted stock mount fixes the issue while inducing more nore vibrations than stock. interior plastic rattles drive me nuts on a daily driver, i wouldnt do them on that kind of setup but its personal preference. Same reason i yanked the poly body mounts out of my truck in a matter of two days because the increase in vibration and noise was terrible.

easy way to tell about the mount is to lift the hood up so you can see the engine from the driver seat, put the truck in 4wd and start to do a boosted launch. make sure no one is in front of you and you have a clear path should something happen with the brakes. watch the engine as you do this and if the mount is bad, you will see the engine jump up 3-4". putting it in reverse and doing the same test will tell you if the pass side mount is bad as well.

if it is bad and you replace it, id really look at the inside of the boot that keeps blowing or just replace it all together. as they blow off, it tears them up internally (sometimes visable, sometimes not) and they start blowing off easier. it shouldnt be blowing as easy as it is now so its most likely a combo of issues like the motor mounts. A new one is a good piece of mind at this point.

as for boost being low or not, thats dependent on tuning (we dont know what mark has in there for tuning on lvl 3) and possibly boost leak. if mark is only commanding a 2k uS on lvl3, 40 psi doesnt sound far off. if hes commanding 2.5k uS, well then 40psi is low. Log your truck at WOT and see what the highest pulse width is on lvl 3 and take note. you can do the same on lvl 5 and it will give us an idea of the size tunes you have. max timing and what the vave position is at would help as well. We are looking for the numbers ONLY at WOT, between 2800-3200rpm, 3rd gear and up, no tire spinning, and no chopping throttle or doing werid stuff. gotta be a clean run.

did a couple pulls
saw high 30's psi wise on 3 and low 40's on 5
looked liked 1.5k on 3 and 2k on 5, it was hard to watched, I got some logs and i'll put em up here if you want to take a look here in a few

 

[Creeker15]

Here's my logs from today on switch 3 and 5 (it'll show as 2 and 4 on the logs though)
Showing over a little over of 50 psi on both which 5 hits a hell of a lot harder then 3 so maybe that's done in timing?
But my mechanical boost gauge shows 35-37psi for 3 and 41-44 psi.

Thanks for all the help fellas! Still lots to learn over here

edit: just now realizing the boost pressure on the logs includes atmospheric pressure of 14.7 and I live at the beach so no loss there

 

[hntngkd]

the mishimoto crap is junk, waste of money and will leak on you. bad choice.

what size injectors do you have, how big is the tune, any engine work, and has it been dyno'ed or to the track for those numbers you posted? you need to find teh problem before throwing parts at it and hoping it fixes it. that boost is on the low side for said HP numbers and egt's are high. yes it points to the turbo but what you described could be a boost or drive pressure leak or something else that is not letting boost build like it should.

For what its worth ive been running a mishimoto intercooler at 1000hp and 80lbs of boost for close to 5 years now. A single case of good luck i suppose doesnt tell all but i have no complaints about mine. I cant speak on the radiator.

 

[Bdsankey]

For what its worth ive been running a mishimoto intercooler at 1000hp and 80lbs of boost for close to 5 years now. A single case of good luck i suppose doesnt tell all but i have no complaints about mine. I cant speak on the radiator.

The problem with the Mishimoto cores is they're very restrictive. My Mishimoto core caused an approximate 6psi drop across the intercooler at 55psi (over 10% pressure loss) whereas on an LBZ (yes different core) Banks they saw far less drop in pressure (I think it was around 3-4psi at far far more boost) which is 100% related to the core design. The Mishimoto use a bar and plate type construction. It's strong and removes heat well but is restrictive in terms of internal airflow compared to an extruded micro fin core (BD/Northern Radiator/Banks).


Edit: I stand corrected, the Northern Radiator is a hybrid design that incorporates both micro fin and stuffed tube components. They use the extruded micro fin elements at the top and bottom of the core while the center is filled with stuffed tube elements. I just looked inside my BD and can only see micro fin but I didn't use a mirror/borescope so I can only see the ends of the core (I'll try sticking my work phone in there later, my personal phone is too wide to fit into the inlet/outlet).

https://knowledge.northernfactory.com/en/articles/78-charge-air-cooler-core-types-guide?_ga=2.254900812.571130549.1584736663-933999464.1584736663&fbclid=IwAR1wjQpK5ssBzdKZgYwhoeKGWrdXPcjvfzFU6eDgVrsJc0YW7Dn9eQOdQBU

 

[Chevy1925]

For what its worth ive been running a mishimoto intercooler at 1000hp and 80lbs of boost for close to 5 years now. A single case of good luck i suppose doesnt tell all but i have no complaints about mine. I cant speak on the radiator.

thats because its the older good one. my 02 still has the japanese made mishimoto in it as well and i doubt its leaking. When they switch to china made not long after, they went to shit. rads are lucky to go a year before leaking due to core support flex.

 

[hntngkd]

thats because its the older good one. my 02 still has the japanese made mishimoto in it as well and i doubt its leaking. When they switch to china made not long after, they went to shit. rads are lucky to go a year before leaking due to core support flex.

Ahhh i see, i was unaware of the switch to china made parts. Good to know

The problem with the Mishimoto cores is they're very restrictive. My Mishimoto core caused an approximate 6psi drop across the intercooler at 55psi (over 10% pressure loss) whereas on an LBZ (yes different core) Banks they saw far less drop in pressure (I think it was around 3-4psi at far far more boost) which is 100% related to the core design. The Mishimoto use a bar and plate type construction. It's strong and removes heat well but is restrictive in terms of internal airflow compared to an extruded micro fin core (BD/Northern Radiator/Banks).


Edit: I stand corrected, the Northern Radiator is a hybrid design that incorporates both micro fin and stuffed tube components. They use the extruded micro fin elements at the top and bottom of the core while the center is filled with stuffed tube elements. I just looked inside my BD and can only see micro fin but I didn't use a mirror/borescope so I can only see the ends of the core (I'll try sticking my work phone in there later, my personal phone is too wide to fit into the inlet/outlet).

Makes sense, i may have to do a delta pressure check on my truck. If there was that much of a difference at 55psi i can only imagine it would be worse yet at 80+psi

 

[Chevy1925]

Here's my logs from today on switch 3 and 5 (it'll show as 2 and 4 on the logs though)
Showing over a little over of 50 psi on both which 5 hits a hell of a lot harder then 3 so maybe that's done in timing?
But my mechanical boost gauge shows 35-37psi for 3 and 41-44 psi.

Thanks for all the help fellas! Still lots to learn over here

edit: just now realizing the boost pressure on the logs includes atmospheric pressure of 14.7 and I live at the beach so no loss there

your fueling looks good although its tapering off slightly on tune 5. what im seeing though is the big turbo does not want to come to life when you mat it. pirmary turbo is making decent boost, then you mat it and vanes open to move drive pressure towards the big turbo. its building really slowly and should be coming on faster than it is. id check that turbo over well for play, contact with the cover, drive pressure leaks and then boost pressure leaks between turbos and after the primarty turbo.

do you have any boost gauges in teh truck? if so, do you have 2? one between the two turbos and one after both turbos?

 

[MAXX IT OUT]

The problem with the Mishimoto cores is they're very restrictive. My Mishimoto core caused an approximate 6psi drop across the intercooler at 55psi (over 10% pressure loss) whereas on an LBZ (yes different core) Banks they saw far less drop in pressure (I think it was around 3-4psi at far far more boost) which is 100% related to the core design. The Mishimoto use a bar and plate type construction. It's strong and removes heat well but is restrictive in terms of internal airflow compared to an extruded micro fin core (BD/Northern Radiator/Banks).


Edit: I stand corrected, the Northern Radiator is a hybrid design that incorporates both micro fin and stuffed tube components. They use the extruded micro fin elements at the top and bottom of the core while the center is filled with stuffed tube elements. I just looked inside my BD and can only see micro fin but I didn't use a mirror/borescope so I can only see the ends of the core (I'll try sticking my work phone in there later, my personal phone is too wide to fit into the inlet/outlet).

https://knowledge.northernfactory.com/en/articles/78-charge-air-cooler-core-types-guide?_ga=2.254900812.571130549.1584736663-933999464.1584736663&fbclid=IwAR1wjQpK5ssBzdKZgYwhoeKGWrdXPcjvfzFU6eDgVrsJc0YW7Dn9eQOdQBU

So has anyone tried the northern radiator #222328 intercooler? We have one local and might try to get one any see if its any better then the stock one in both pressure and temp drop across the intercooler.

 

[Bdsankey]

So has anyone tried the northern radiator #222328 intercooler? We have one local and might try to get one any see if its any better then the stock one in both pressure and temp drop across the intercooler.

Yes, they are a great intercooler. From what I've been told by my BD rep, the Northern Radiator HD intercoolers in every way other than the Northern Radiator ones do not have the BD logo on them and they also aren't coated black.

 

[Creeker15]

your fueling looks good although its tapering off slightly on tune 5. what im seeing though is the big turbo does not want to come to life when you mat it. pirmary turbo is making decent boost, then you mat it and vanes open to move drive pressure towards the big turbo. its building really slowly and should be coming on faster than it is. id check that turbo over well for play, contact with the cover, drive pressure leaks and then boost pressure leaks between turbos and after the primarty turbo.

do you have any boost gauges in teh truck? if so, do you have 2? one between the two turbos and one after both turbos?

I only have the one gauge tapped before the y bridge.
480 looked good last I had it off but if it’s bad, then excuse to get a billet 485 or 488

I’ll look over her when I get home I really appreciate it.

 

[Chevy1925]

I only have the one gauge tapped before the y bridge.
480 looked good last I had it off but if it’s bad, then excuse to get a billet 485 or 488

I’ll look over her when I get home I really appreciate it.

How smokey is once your feel you are on top of the chargers?

 

[Creeker15]

How smokey is once your feel you are on top of the chargers?

It's not too hazy but I can tell on spool up it's definitely smokier then it used to, it's kinda hard to see the haze as well as my axle dump fell off and haven't welded it on, so it's mid cab dump lmao. Though spool up is like driving a gigantic single, takes either til 4k in 2nd to carry over into 3rd or at almost the end of 3rd. I don't think compounds this sized need an entire gear to spool.

I'm about to go look at the S480 here in a sec. The impeller on the 3794 had either a scrap on one of the blades or where i touched it with my finger.

 

[Creeker15]

your fueling looks good although its tapering off slightly on tune 5. what im seeing though is the big turbo does not want to come to life when you mat it. pirmary turbo is making decent boost, then you mat it and vanes open to move drive pressure towards the big turbo. its building really slowly and should be coming on faster than it is. id check that turbo over well for play, contact with the cover, drive pressure leaks and then boost pressure leaks between turbos and after the primarty turbo.

do you have any boost gauges in teh truck? if so, do you have 2? one between the two turbos and one after both turbos?

Got some shaft play :/

wheel spins fantastic. I was unable to move the 3794 wheel whatsoever even though it doesn’t like to spin nearly as easily as this one.

no scoring, scrapes or touching the housing whatsoever. Blades look immaculate to me. However it does have play and can’t be spun if pushed much. No in and out play I could feel though
Having trouble uploading video give me a bit

Edit: here we go. And here’s a pic of the 3794 blades. Spin fine just stops spinning faster then the 480. And no play not even a tiny bit

Double edit: both chargers have around 25k miles and are about a year old. Most the mileage being interstate unloaded.

 

[Chevy1925]

In and out play is more concerning than side to side on a journal bearing turbo. That 480 looks looser than I like but it’s not rubbing and no in and out so I would not say it’s your issue. The 37 being tight sounds interesting. The scrapes are probably from you taking the cover on and off.

I’d look for any soot around any exhaust parts from manifolds all the way to 480 down pipe

 

[Creeker15]

In and out play is more concerning than side to side on a journal bearing turbo. That 480 looks looser than I like but it’s not rubbing and no in and out so I would not say it’s your issue. The 37 being tight sounds interesting. The scrapes are probably from you taking the cover on and off.

I’d look for any soot around any exhaust parts from manifolds all the way to 480 down pipe

Yeah I checked I couldn’t find anything loose or any spot in the engine bay. I’ll look around the drivers side manifold tomorrow
There’s a slight gap on the charge pipe from the s480 outlet but it has been there since I’ve owned the truck and the v band pulls it together quite nicely.
it also pegged the 60psi boost gauge like that once upon a time.
Hopefully turbo is intact on the exhaust side. I should’ve cranked it.

yeah as far as small turbo it doesn’t spin nearly as easy as the s480 but it drives normal. And you’re definitely right about the 480 being slow because I’ve always thought it doesn’t sound like it spools with just a little throttle cause I use to just give it a little extra throttle and you’d hear her whine up sounding nasty without really doing anything but accelerate normally

 

[Creeker15]

Well had a local turbo guy check out the S480
Says he can’t promise me that it’s the root of my boost problems but could definitely be a contributing factor and it’s his recommendation it needs to be rebuilt. Kinda sucks but excuse to get a bigger boi and send this unit off to get rebuilt and sold

I don’t have time to pull the turbo off since I deploy Tuesday and have worked and will work everyday until then (these saturdays have infact not been for the boys) Sister unit just went to Afghanistan so maybe we’ll get to go and I get to make some extra coin. The Middle East sucks, stupid hot 24/7 but that pay is noice!

but I’ll still be lurking the forums, posting and bugging people with my million and ten questions.
@Bdsankey is helping me with getting a ton of parts ordered and hopefully by the time I’m back the truck will be paintmarched and suspension powder coated!

Thanks to everyone help me narrow this down.
Especially @Chevy1925 and @Bdsankey For guiding me and teaching me!

 

[Kunz111]

Just noticed Creeker said that he might be going to Afghan, I hope he didn’t and his sister unit got out ok. Shitty to see what happened over there.

 

[monster50iii]

You can thank our current commander in chief on that one.