I've read here that going up to 35 PSI boost or more and you risk losing the head gasket. My '05 CTD Dually is in the hands of a good friend that I sold it to. He confirms what I recall and that is I would often see 39-40 PSI boost on that truck with the Edge box set at level 2. It's got 60,000 miles or so on it and it's always been pulling a thirty seven foot fifth wheel. No problems on the head gasket on that one. With the Edge on level 2 it's theoretically about 400 HP. Now I know that number is bogus, but it pulls pretty much like my new truck with the MiniMax on level 1.

So, what's the story? Is the 6.7 head gasket design fundamentally different from the 5.9?

 

First day with mine running - yeah, oh yeah!

I've got it set on "no power" and 0 timing - and it still has so much more than before. Even at these settings I have seen 32lbs boost just pulling out on the highway. I'm getting two responses - one from the mini maxx reads 31lbs and the second from my autometer boost gauge shows 35lbs at the same time.

 

Seems from what I've read the people who run H&S with power while towing blow the HG. I've not read about a 6.7 and smarty blowing one. I read 1 about a stock truck blowing.

 

That's interesting. Perhaps the sensor that talks to the vehicle ECM is located in a place that reads lower than where your after market boost gauge probe is? Is your after maker gauge pre-intercooler or after?

 

After. I tapped into the plate that covers the lost EGR hole.

 

Its really quite simple, run a tuner and blow a head gasket. Alas, afterwards in the not so distant future look forward to sinking say $7 to 10K in a new tranny. Its not rocket science.

 

Studs and a G56 with a good clutch. 3 grand. Both issues become non existant.

 

I've run a few 43psi pulls with my 2010 with no issues. If you want to run that much boost often, I would at least install head studs. When mine goes I'm going to run a different head gasket than stock. I'm also sitting on a spare 6.7L engine that has already has been fixed.

 

I'm going to tighten the bolts on the head today. Is there a sequence thats recommended for tightening?

 

When I am towing i am running on the Wild setting on my H&S....I'm not hammering on it, but yes I can get the boost up there, but i figure I will wait till I blow the gasket before I resort to opening up the top of the motor. Then I will install studs and a new gasket.

 

Here is my take, if you regularly see 30+PSI, get some ARP 625's. No one can argue this, studs are much cheaper than a blown gasket.

 

Did you clean your factory sensor? On our first truck it was almost completely plugged with carbon, so bad in fact we replaced it, then on the second truck it also was very dirty but we just cleaned it.

I think if you have the capability to defuel for cold coolant, boost and EGT why not set up for 28psi boost and 1300F EGT quite conservative numbers.

 

I 2nd the 1300F EGT recommendation!!

Even though I am studded and do not care about the boost, I set my pyro defuel at 1300