6.7l wastegate
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#12
no offence to the 5.9 guys ,but the is a different animal we have crazy high cylinder pressures (which is what causes our blown head gaskets)the material in between cylinders is a little less and it does contribute to the gasket being weaker. I blew my stock gasket on stock bolts, stock injectors, stock turbo, the only other thing I had was a blackmaxx (the mp8 was not on the truck) these trucks will blow headgaskets with just a programmer. And studs and a wastegate will help ,but they are not a cure all. My truck blew its seconds headgasket with my turbo now AND 625 studs. Again its not the boost that blows it it's cylinder pressure. if you want to run your programmer on its higher setting you will at minimum need studs and a wastegate. There is a experimental gasket coming soon that could cure our problems.
EDIT: ,and the head and the block where both checked for flatness after the first blown gasket.
EDIT: ,and the head and the block where both checked for flatness after the first blown gasket.
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mikeshauling (10-30-2010)
#13
I've seen a stock turbo equipped 6.7 make 555 hp on the stock head bolts, and that particular run didn't blow the gasket, but it did contribute to its demise. From a performance standpoint, the stock gaskets even with studs aren't up to the task of holding big power. That same 6.7 I spoke of made over 700 hp with a new gasket, bigger turbo, and 625s, and the replacement stock gasket started leaking not too long afterward.
Like I said earlier, a fix is in development testing as we speak. Once the testing is complete, the fix will be available to the public, and yes dyno videos and sheets will be posted.
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dodgeram082500 (11-01-2010)
#14
dodgeram is right. i blew my head gasket with stock bolts. i had my head decked. it was off about .012. i then put in my allen bolts and bought a waste gate. so far no troubles. i hooked up a gauge to check drive pressure. 24 lb boost i had about 24 lb of drive pressure. after that the drive pressure really climbed away from boost pressure. i know 37 lb of boost was crazy high drive pressure. my gauge jumped alot but it was close to a hundred lb. needless to say i dont run that high now
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dodgeram082500 (10-31-2010)
#15
Drive pressure has zero effect on the headgasket. It can withstand thousands of psi in combustion pressure, 70psi of backpressure means nothing to the engine.
The only thing backpressure has an effect on is the valve springs, and Cummins designed them to hold the pressure.
The headgasket blows because the thickness between the cylinders is thinner due to the larger bore. To solve the blowing gasket problem you need a better gasket and/or studs.
The only thing backpressure has an effect on is the valve springs, and Cummins designed them to hold the pressure.
The headgasket blows because the thickness between the cylinders is thinner due to the larger bore. To solve the blowing gasket problem you need a better gasket and/or studs.
Last edited by ForcedInduction; 10-31-2010 at 04:19 AM.
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I agree that drive pressure isn't a direct cause of head gasket failure ,but it is related to what is causing the failures high drive pressure is related to high cylinder pressure so it is related to what's happening to the head gasket. When you add fuel and more boost and the bigger bore and stroke you have high cylinder pressure. I am not an expert all I know is what I've learned from experience. The new gasket will be available after the quick 16 race in Florida ,or maybe sooner. I talk to the designer and get a rough estimate
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dodgeram082500 (10-31-2010)
#20