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LT smoke

boost?

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quick question ..does any one know at what point the stock turbo hx 35 i think needs the waste gate hooked back up if at ? i havent made any huge performance upgrades yet ..just a few minor ones but i know at some point i will need to think about getting the waste gate working again to keep the turbo safe

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to be honest with you my WG is capped off!!!:ahhh:

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Shouldn't go over 35psi. Over that it just generates heat. Over 40-45PSI it probably gets into self destruct mode. I know a lot of guys (with trucks less modded than mine) who blow up the HX just because they capped the wastegate.

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well hmmm i guess i need to see how much boost im makeing then

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i have seen max of 36 psi with my edge up on 5x5.

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Even with my wastegate hooked up I can still touch the high side pin barely at 35 PSI... I'm sure I could go past 35 PSI without a wastegate hooked up. :stuned:

Shouldn't go over 35psi. Over that it just generates heat. Over 40-45PSI it probably gets into self destruct mode. I know a lot of guys (with trucks less modded than mine) who blow up the HX just because they capped the wastegate.

But ISX is right its best to stay below 35 PSI... But also be aware if you reaching 40-45 PSI you better start thinking head studs...

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But also be aware if you reaching 40-45 PSI you better start thinking head studs...

Mike Got any reference or whatever for that - just curious. Was speaking with thracing on chat with ISX and his opinion was headstuds not required under 600HP (Ithink thats what he said). That would be more than 40-45 PSI right ?? Like closer to 55 Just curious as seem to hear different things from different people. Guess its how cautious you want to be ......

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i dont have any reference either but i have been told by many not to go over 45 psi, JKidd was one of the folks!:smart:

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i dont have any reference either but i have been told by many not to go over 45 psi, JKidd was one of the folks!:smart:

Just general chatter I've always heard the lowest burst point is about 40-45 PSI on head gaskets... But seen several reports of people getting lucky as high as 60 PSI on stock gaskets, bolts, etc... But I look at it this way... It best to fix the weak link first before you actually break it... An afternoon of doing head studs is more fun than a full day of doing a head gasket... IMHO...:2cents:

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Studs are not the issue, its the gasket itself, o-ringing the head and or fire ringing them is whats important. There are probably just as many highly modded cummins running stock head bolts as are running studs. If running injectables or boost over 50-60lbs regularly then I would definately run studs, otherwise stock bolts are going to hold things tight enough for the masses.

My 02 setup sees 42psi regularly and has 120k on it and being at 560hp for around 4 years and 60k miles of being a DD and sled pulling and drag racing at that level is still a virgin engine meaning the head has never been off it yet and it has stock head bolts in it.

--- Update to the previous post...

As far as safe psi for the original post do not go over 35 psi Max if you don't want to be digging turbo pieces out of the aftercooler or exhast system, not to mention the high egts you will see at that point.

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thats interesting i have been told that the head bolts wont hold and that they will lift if you get over 45 psi!?! :shrug: and that fire ringing the head is for very high psi and additives such as nitrous.:shrug: you learn something new everyday.:smart:

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Studs are not the issue, its the gasket itself, o-ringing the head and or fire ringing them is whats important. There are probably just as many highly modded cummins running stock head bolts as are running studs. If running injectables or boost over 50-60lbs regularly then I would definately run studs, otherwise stock bolts are going to hold things tight enough for the masses

.

My 02 setup sees 42psi regularly and has 120k on it and being at 560hp for around 4 years and 60k miles of being a DD and sled pulling and drag racing at that level is still a virgin engine meaning the head has never been off it yet and it has stock head bolts in it.

As far as safe psi for the original post do not go over 35 psi Max if you don't want to be digging turbo pieces out of the aftercooler or exhast system, not to mention the high egts you will see at that point.

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Yeah this is what I have heard a few times. Guess trouble can occur at any power level or psi If things not aligned ... But good to know you can go to 45 psi and 500hp and not require studs

John you are running water meth aren't you? If yes then I would suggest studs. Just because boost pressure is around 40 psi doesn't take into account the increased cylinder pressure from any sort of injectables like water / methenal or nitrous or propane ect. My setup is fuel only which is a big reason for the long lucky streak with the factory head gasket.

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John you are running water meth aren't you? If yes then I would suggest studs. Just because boost pressure is around 40 psi doesn't take into account the increased cylinder pressure from any sort of injectables like water / methenal or nitrous or propane ect. My setup is fuel only which is a big reason for the long lucky streak with the factory head gasket.

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so about that wastegate control....I used to get 33psi with my 12v.I only have a 35psi gauge and I can bury it now with the 24v. I'm still giving manifold pressure to the wastegate, and I actually just stepped up line size from 1/4" to 5/16" but it didn't make a difference.There was a small orifice fitting in the stock boost line configuration but I was pretty sure that was on the line to the AFC. That's gone and my fueling is spot on.Any clues? Maybe I should start a new thread but it seemed to fit here.

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