Time for TOUGH pistons!
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From: Knoxville, TN
The MP-8 isn't a timing box, but it will advance the timing some...especially if you're right on the edge.
As you know, timing refers to when the fuel is being injected. If you are running increased rail pressure (like with the MP-8 on 100%), the fuel is being injected faster/sooner...thus, the fuel timing is "advanced".
On the instrumented engines at work, we see evidence of this as the cylinder pressure trace shifts slightly with increased rail pressure. The same phenomemon occurs with larger injectors...thus the reason for the Smarty timing options for "aftermarket injectors".
--Eric
As you know, timing refers to when the fuel is being injected. If you are running increased rail pressure (like with the MP-8 on 100%), the fuel is being injected faster/sooner...thus, the fuel timing is "advanced".
On the instrumented engines at work, we see evidence of this as the cylinder pressure trace shifts slightly with increased rail pressure. The same phenomemon occurs with larger injectors...thus the reason for the Smarty timing options for "aftermarket injectors".
--Eric
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From: Mexico!
Eric, thats what i was thinking too, but wasnt sure! it seemed to rattle more with the mp-8 turned up.
ON EDIT:
im now seeing 26,500 Rp all the time at WOT!
moving from 50% on the mp-8 up to 100% doesnt seem to make any difference on Rail pressure. does the Quad RP gauge read higher then 26k?
i have no clue why its making only about 60 psi boost!
ON EDIT:
im now seeing 26,500 Rp all the time at WOT!
moving from 50% on the mp-8 up to 100% doesnt seem to make any difference on Rail pressure. does the Quad RP gauge read higher then 26k?
i have no clue why its making only about 60 psi boost!
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Default is the most advanced of the timing options, so your intracylinder temps were way higher than the egt's. That explains the meltdown. With injectors of any size run number 2 or 3 for timing, it makes the egt's actually mean something.
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From: Vancouver Island BC
12v,
Nothing wrong with the stock pistons or compression for you application.
Not that I recommend it, but I have been daily driving with Flux 6.2's and stock pistons/compression (slightly thicker headgasket).
Once you go much bigger than Flux 3.0's your setup must be right or expensive consequences will result....Been there, done that, paid the bill.
Clearly you have some form of airflow problem (lack of boost). Airflow is what cools a diesel and without significant cooling the aluminum melts or is burned away. The stock intake causes #5 and#6 to run a bit hotter than the others. Had you melted cylinder #2 I might look at something else, but burning #6 is a direct result of extreme egts.
Getting pistons made or coated with some sort of unobtainium will not solve your problem.
What I am telling you is that you had better get your problem solved before firing up the new motor because you will burn that one too.....Just trying to save you from more pain!
Good luck!
Nothing wrong with the stock pistons or compression for you application.
Not that I recommend it, but I have been daily driving with Flux 6.2's and stock pistons/compression (slightly thicker headgasket).
Once you go much bigger than Flux 3.0's your setup must be right or expensive consequences will result....Been there, done that, paid the bill.
Clearly you have some form of airflow problem (lack of boost). Airflow is what cools a diesel and without significant cooling the aluminum melts or is burned away. The stock intake causes #5 and#6 to run a bit hotter than the others. Had you melted cylinder #2 I might look at something else, but burning #6 is a direct result of extreme egts.
Getting pistons made or coated with some sort of unobtainium will not solve your problem.
What I am telling you is that you had better get your problem solved before firing up the new motor because you will burn that one too.....Just trying to save you from more pain!
Good luck!
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From: In the Shop
So many ideas! on pistons and compression drop...
Someone suggested the Q480 piston, which i believe is cummins.
Others arias, but then i hear about seizing problems with the forged pistons?!
BTW its a daily driver, and we live at 6,700 feet elevation!
The overheating problem might have arised from too much luging, the wastegate was stuck open, and turbos spooled hard, BTW on the run where that happened timing was on default and SW9 mp-8 on kill. it rattled really bad!
Does mp-8 add timing? or why does it rattle now more then it did with smarty alone?
Im not sure on the egts, cant watch all gauges in less then 12 seconds. i believe they musta reached 1600
Someone suggested the Q480 piston, which i believe is cummins.
Others arias, but then i hear about seizing problems with the forged pistons?!
BTW its a daily driver, and we live at 6,700 feet elevation!
The overheating problem might have arised from too much luging, the wastegate was stuck open, and turbos spooled hard, BTW on the run where that happened timing was on default and SW9 mp-8 on kill. it rattled really bad!
Does mp-8 add timing? or why does it rattle now more then it did with smarty alone?
Im not sure on the egts, cant watch all gauges in less then 12 seconds. i believe they musta reached 1600
The QSB Piston wont fit the year engine you have, Wrong bowl design.
Use water injection, but with little to no meth.
The stock pistons are the best bet in that year engine, IMO
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From: Home of the Beaver
Thread Starter
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From: Mexico!
Should we bore up all cylinders to .20 over and get .20 over stock cummins pistons?
Where's the best place to get them?
Just want the VERY BEST and not do things again!
The cam we are going with should help egts too. Im open to suggestions on that one too!
Where's the best place to get them?
Just want the VERY BEST and not do things again!
The cam we are going with should help egts too. Im open to suggestions on that one too!
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From: Mexico!
snapoff: Chihuahua state, about 5 hours from Texas
A local diesel parts store has a brand new complete bottom end (block, pistons, rods, crankshaft, cam etc...) which is a bit cheaper then new .20 over OEM pistons and rings.
Should we go and change out the whole block and reassemle the truck?
A local diesel parts store has a brand new complete bottom end (block, pistons, rods, crankshaft, cam etc...) which is a bit cheaper then new .20 over OEM pistons and rings.
Should we go and change out the whole block and reassemle the truck?
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Joined: Dec 2007
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From: New Jersey Shore
Try these:
Mahle Monotherm Steel Racing Pistons
http://martincoadvertising.com/pr/20...-race-pistons/
-Chris
Mahle Monotherm Steel Racing Pistons
http://martincoadvertising.com/pr/20...-race-pistons/
-Chris
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From: Klamath Falls, OR
In another thread you said that you ran a 24V gasket, and then switched back to an MLS. When you had the 24V gasket on, did you modify the cooling passage holes? If not, the coolant flow to number 6 is severly reduced. Just a thought on what may have contributed to the problem....
Paul
Paul
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From: Mexico!
i didnt modify the 24v head gasket! after the 24v Head gasket blew, switched to a 12v marine .20 over marine head gasket.
Do you all think we will get along with new stock pistons? Who knows the truck might end up not being a daily driver anymore anyway
Do you all think we will get along with new stock pistons? Who knows the truck might end up not being a daily driver anymore anyway
