Too much boost?

[dodge_em]

Anyone know how much boost the head gasket can take in stock form. I can hit just over 40psi under WOT with a load behind me. Is this going to cause any damage for brief periods. Should I adjust the wastegate?

[six pack]

That sounds like too much to me but hey, it is over twice what factory boost is.

Just did the numbers and with that much boost that would be comparable to a 980 cubic inch naturally aspirated engine. Gotta love the boost:D

[PSiemens]

Dodge_Em

If the turbocharger is factory, you are operating it outside of its efficiency map at 40 PSI. Factory turbo is good for 35 or 36 pounds boost. If your timing has been advanced beyond 16* or so, then there is a possibility of head gasket failure. The intercooler will usually handle 50 PSI before failure. Watch that EGT gauge. Is gauge mounted pre or post turbo? What temps are you seeing at 40 PSI?
Phil

[dodge_em]

Pyrometer is mounted post turbo in the cast iron elbow of the down pipe in the exhaust. Now that I have the 4" mandrel bent exhaust, I can't get the temps to climb above 850°F no matter what I do. Temps climb the highest under load when the boost is low, and fuel delivery is high. When the boost increases, temps will fall. I have been recently told that my turbo housing is perhaps too small. It is starting to brown a bit. So perhaps I will look at upgrading it at sometime in the future. Does anyone know if the larger 12 Valve turbo housing is a direct replacement for mine? Any pros or cons with that replacement. If I find just a housing, will the turbine and internals from my turbo work with it?

[PSiemens]

Dodge_Em

I pull trailers (sometimes very heavy) too. My pyro is mounted pre turbo. I could melt the pistons. I do not like to get my pyro temp over 1100*F.
If I am not mistaken, you have a HX35 with a 12 cm exhaust housing. Someone correct me if I am mistaken.
If the above is your set-up, then the only direct bolt on would be a 14 cm exhaust housing with wastegate.
A 16cm exhaust housing will drop EGT a minimum of 100*F but most enthusiasts experienced more. The 16 cm exhaust housing requires that the exhaust be moved an inch or two forward. 16 cm exhaust housings do not have a wastegate.
Changing the turbo housing to one from a 12 valve will not drop exhaust temps, but changing the exhaust housing ti either a 14 cm or 16 cm will.
Phil

[dodge_em]

Phil,
Thanks for the input. Sounds like some great advice. It will give me more research:STY: to do. :rolleyes:

[WARLOCK]

Have you looked in to www.bankspower.com?

[dodge_em]

I have looked at Banks. They have some great products, that do what they advertise, and work very well with the other components in their systems. I tend to like to pick and choose what components I am going to add, after some research, asking a lot of questions, and of course, looking at the value side of things. I have quite a bit of useable power increase so far, with just the K&N Filter, larger exhaust, and the JVD Torque Enhancer box that I had installed. With the JVD box, also came a couple of other mods to the turbo wastegate and MAP sensor to allow more boost to build above what stock would allow. I am not opposed to Banks' stuff at all. Just sort of putting together my mods one at a time as I find what I want for my specific purpose, and budget will allow.

[DROPT_98_DAKOTA]

take a look at www.bd-power.com they are a popular diesel tuner on the west coast of canada.

[lbeenken]

get a pyro with the prongs that go in the head itself not the exhaust pipe. this will really let ya know if your gonna melt it down. then youll know if any hot spots are there.

[dodge_em]

Somebody correct me if I am mistaken on this, but I had thought that the purpose to mounting the pyrometer near the turbo, either before or after, was to make sure the temps are getting so high as to cook the turbo, being as it is oil cooled. I don't discredit the fact that you don't want piston meltdown either, but thought that the Exhaust Gas Temperatures (EGT's) were important to monitor for the sake and longevity of the turbo. I am including a picture of what my turbo looks like right now. Although my EGT's aren't getting that high, the amount of boost I am developing seems to really superheat the air. Any opinions on this pic?

[six pack]

My understanding is that you want them as close to the cylinder head as possible to get a better reading of combustion temperatures. This is so you can back out of it before you melt the pistons down(and of course monitors the fuel burn) and has nothing to do with the turbo.

dodge_em,

I have never seen a turbo that looked liked it was getting as hot as yours judging from the paint discoloration of the inlet housing.
You might want to check into that.

[PSiemens]

I like the picture. Makes me wish for a digital camera.
Your turbo is showing signs of heat. The discoloration is the proof.
A pyro serves at least 2 purposes:
1.) lets you know when you are about to melt a piston.**
2.) lets you know when it is safe to turn off motor so you don't hurt the turbo.
3.) It will tell you if that new air box mod is beneficial etc. .....

** Mounting of the pyro probe is best done pre-turbo. The EGT readings react quickest the closer to the head that you are. Figure that the aluminum in the piston melts at 1300* or so, but piston scuffing will occur before piston melt-down.

To sum up, the primary use for the pyro is to prevent engine damage and the secondary use is to prevent turbo damage.

Figure that 850* post turbo equals about 1150* pre-turbo and that 40 PSI boost is a little out of the efficiency map of the stock HX35W turbo. As you boost above the efficiency map, the turbo is really heating the air and the discoloration is the result. That is not good for making power nor good for turbo life.

A bigger exhaust housing, either a 14 or 16 cm will drop your EGT and the turbo will run cooler.

[dodge_em]

Thanks for the input guys. I am really quite surprised that the dealer hasn't said a word about the color of the turbo housing. I have had them do all my oil changes during my truck's 102,000 mile life so far, and they have to see it when they change the filter, I would think. They would have to know that a stock truck wouldn't develop that sort of heat, but who knows. I would like to get a bigger turbo, but before I do any more engine mods, I will just keep my right foot out of the kitchen a little until I get the tranny upgraded. Then I can make the additional engine mods that I plan on making, like bigger injectors, and perhaps even a propane topper kit on down the road.

For now, I will just drive normally, if that is possible, and keep the EGT's (post turbo) under 600° and should be okay. I always let it cool to about 300° before shutting down.

[lbeenken]

you might also like to check to see if you got a vaccuum leak on the wastegate. That will lead to the additional boost you claim to have on tap also
could be a simple fix and may be producin the extra heat you dont want

[dodge_em]

The extra boost that I claim to have is as a result of modifications done to the wastegate and also the MAP sensor. The boost guage is tapped in the inlet housing just above the grid heater, so is measuring manifold boost pressure as accurate as I can get it. The heat is a bit of a concern, so I am looking for ways of reducing the heat without reducing the boost. Thanks for the helpful hints though... every little bit is appreciated.

[dodgeram]

I just got an edge comp and set of RV275 injectors installed

I hit 38lbs of boost with the box turned on and on it's highest setting, I found my scotty II air intake (with the cowl hole cut) reduced my egt's a lot ........

I only hit 1100 degrees pre turbo when running WOT now (it was an easy 1300 before)

I've been told a 4" exhuast will reduce my EGT's a further 100 degrees

check out www.wildcatdiesel.com , it's where I got all my stuff, Rod's a great guy, very helpfull and a cummins owner himself :)

there's a link to the air cleaner in my sig .........you can see some pics of it on my stereo install page :)

oh yeah you do not want to reduce boost , the extra boost over stock is needed to keep the egt's down .......you may want to look into an hx40 if you think you need it :)

Rod's partner and R&D man runs a B1 quickspool with 60 lbs of boost and I believe he still has the stock head gasket , he's running 550 HP and pulls very heavy loads at those levels