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Discussion Starter · #22 ·
I have a VE I started with the 7cm when living at 500' but changed to a 6cm after moving to 5,000', that change was enough to keep the same fueling while maintaining EGT's and little to no smoke on take off the 7cm was a little smoky above 4,000'. The 221 with the 6cm was totally user friendly from sea level to 8,000'.
did you've always have a 3 in exhaust
 

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Yes 3" with a tight 90* at the turbo then a flex sweep ~ 24" long and a 90* turnout at the back with no muffler.
 

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Discussion Starter · #26 ·
and your thoughts are sorry it's in Celsius but couldn't find one in Fahrenheit now they're all over the place
 

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and your thoughts are sorry it's in Celsius but couldn't find one in Fahrenheit now they're all over the place
That does seem higher than it should be mine when running the 221 would never no north of 1,000F unless I was at WOT for a bit, have you tried advancing your injection timing more than what it is now? This link explains effects of pump timing and will help you decide where it is best for your rig... B & C series timing
more timing should lower total boost as well as decrease EGT's so might be worth the time to see what it does for you.
 

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Once you are at speed and cruising at a constant rpm do your EGT's go down any or do they stay at ~700C ?
 

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3" from the hot pipe back and no muffler, it makes no real noise out the exhaust.
A guy who drives past my work has a straight pipe with either no muffler or one that doesn't do anything. It's quiet enough until he hits max boost and the wastegate opens and then it sounds loud and awful!
 

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What's your radiator setup?
IMO 700C isn't a problem at all. My 4BD1T saw 900C a few times (inattention while towing) along with 750C sustained many times and suffered zero issues. I have since rebuilt the motor and there was no thermal damage to pistons.
My tdi skoda runs 800C under a sustained pull also without issues (it's got factory sensors I think post-turbo and before DPF).

I believe the people who melt stuff at 1200F (for example) have probes that for various reasons aren't picking up true temperatures.
 

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A guy who drives past my work has a straight pipe with either no muffler or one that doesn't do anything. It's quiet enough until he hits max boost and the wastegate opens and then it sounds loud and awful!
I was really surprised that it does not make much noise but with the he221 I did notice exhaust noise when the gate is open but only when a wall is on the passenger side, with the compounds I never hear it. I guess I need to have the Wife drive it by me while standing beside the road to know for sure but i have never been told by neighbors that is is annoying.
I guess it could be that my hearing has deteriorated so much that I do not notice it... now I need to find out as I have never been a fan of loud exhaust.
 

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I was really surprised that it does not make much noise but with the he221 I did notice exhaust noise when the gate is open but only when a wall is on the passenger side, with the compounds I never hear it. I guess I need to have the Wife drive it by me while standing beside the road to know for sure but i have never been told by neighbors that is is annoying.
I guess it could be that my hearing has deteriorated so much that I do not notice it... now I need to find out as I have never been a fan of loud exhaust.
Compounds are always going to be quiet compared to a single.
 

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Discussion Starter · #33 ·
That does seem higher than it should be mine when running the 221 would never no north of 1,000F unless I was at WOT for a bit, have you tried advancing your injection timing more than what it is now? This link explains effects of pump timing and will help you decide where it is best for your rig... B & C series timing
more timing should lower total boost as well as decrease EGT's so might be worth the time to see what it does for you.
been there done that unfortunately it didn't help much so i put it back and it made it sound like it was over working it self it mad it chatter and that's 1300° in 7 seconds that's not normal
 

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Discussion Starter · #35 ·
A guy who drives past my work has a straight pipe with either no muffler or one that doesn't do anything. It's quiet enough until he hits max boost and the wastegate opens and then it sounds loud and awful!
i very much agree that's why i used 2 resignators works like a glasspack but sounds like a muffler.
 

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Discussion Starter · #36 ·
I was really surprised that it does not make much noise but with the he221 I did notice exhaust noise when the gate is open but only when a wall is on the passenger side, with the compounds I never hear it. I guess I need to have the Wife drive it by me while standing beside the road to know for sure but i have never been told by neighbors that is is annoying.
I guess it could be that my hearing has deteriorated so much that I do not notice it... now I need to find out as I have never been a fan of loud exhaust.
4bt motor are loader than the exhaust sounds the guy down the street has one in his s10 with straight pipes all i hear is the sound of a chattering motor but i like mine quite that's another reason i want with 4bd1t vs 4bt don't get me wrong they both sound like a tractor driving down the road one a little less than the other but give me a 12v 6bt any day.
 

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Discussion Starter · #37 ·
What's your radiator setup?
IMO 700C isn't a problem at all. My 4BD1T saw 900C a few times (inattention while towing) along with 750C sustained many times and suffered zero issues. I have since rebuilt the motor and there was no thermal damage to pistons.
My tdi skoda runs 800C under a sustained pull also without issues (it's got factory sensors I think post-turbo and before DPF).

I believe the people who melt stuff at 1200F (for example) have probes that for various reasons aren't picking up true temperatures.
I've seen people all over the place with egts all the diesel mechanics I know tell me to never exceed 1400° for more than a few seconds and max continuous 1250. i use a 3 fan system 2 12v and 1 flex 13" might change it to a solid 14" idk will see it's never got over 200° when pulling anything in 90° wether
 

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Discussion Starter · #38 ·
my two cents I would never run a 4bt at 1,400° ever especially since they are a non-sleeve motor that would be one costly repair also another reason to go with the 4bd series over the Cummings the only fall that I've ever seen with in Isuzu are their heads
 

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Discussion Starter · #39 ·
If the 3" exhaust don't fix the problem 100% it's the he221 turbine housing is to small it can get rid of the exhaust fast enough. my buddy on here has a modified hx30 his highest temp ever is 1100°
 

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my two cents I would never run a 4bt at 1,400° ever especially since they are a non-sleeve motor that would be one costly repair also another reason to go with the 4bd series over the Cummings the only fall that I've ever seen with in Isuzu are their heads
Over the years I have used 1,200* as my max and adjusted my fueling/timing where even with a long hard pull in the summer it max's out there, I guess if I was the only one to drive it I could work with it higher but friends and family use it now and then when needing to tow and they might not watch it like I do so I'm comfortable there that its pretty foolproof. There is a really long grade on I-40 west between Needles and Barstow that i have ran many times with it north of 100* so I know it's safe where it's at.
 
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