Pilot Injection!! Can it be turned off??? Anyone know?

nrussell said:
I thought you guys might be at the suncoast redneck nationals, but i guess not. I need Jeff to install my cam and springs. I have a job in the virgin islands in the middle of march and will probably drop it off before i leave. See if jeff will put different pistons in from the bottom while it's still in the frame, just an idea. i believe he replaced the rings on my pistons that way. you guys did a great job on that install too, sucks about the rattle though!
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Nah!! Jeff took his family to Louisianna this weekend in the NEW Silverline Bus!!!

So I won't be able to get back down there until Wed. and Thurs. of next week....

Well, I'm gonna try to exhaust all options with the help of Don and a few idea's of others first!! I DON'T wanna have to crack open the engine unless Absolutely ness......

Jeff's not really concerned about the noise either!! But others have express concern for what it'll do to my cylinder walls and HG over time!!
 
lmills said:
.100??? or do you mean .010 off the top??
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100/1000ths.........It looked like about an eigth of an inch of the top, sitting beside a stock piston...

Pardon my ignorance on how to type it......I guess that would be .100....right?
 
Big Swole said:
Nah!! Jeff took his family to Louisianna this weekend in the NEW Silverline Bus!!!

So I won't be able to get back down there until Wed. and Thurs. of next week....

Well, I'm gonna try to exhaust all options with the help of Don and a few idea's of others first!! I DON'T wanna have to crack open the engine unless Absolutely ness......

Jeff's not really concerned about the noise either!! But others have express concern for what it'll do to my cylinder walls and HG over time!!
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The '09 race tour bus! yeah come on! i need to visit the shop. so you will be there wed and thurs? if so i will be there. if the injector upgrade works that would be good. say bye 755HP and hello 800-900HP, holy chit!!
 
Big Swole said:
100/1000ths.........It looked like about an eigth of an inch of the top, sitting beside a stock piston...

Pardon my ignorance on how to type it......I guess that would be .100....right?
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yes, you are correct. I also thought that was what you meant in the first post. :D
 
Rattle is the result of large turbos and heavy fueling. Any time the ECM see the throttle position increase it will increase the rail pressure. Boost or not the rail will come up. Stock chargers will make boost as quick as the pedal goes down, this deleting the fuel rattle created by injector pressure and timing. As mentioned boost eliminates the sound by burning the fuel and creating some heat. ECM timing does not consider the injector size.. Larger stick will derail the regular rate of injection and be dumping more fuel at the same rate as a stock stick. Fuel not being burnt in a cold cylinder or semi warm combustion chamber will simply result in irregular rattle noises.

Eliminating injection events may or may not be the answer.
 
onetun said:
Rattle is the result of large turbos and heavy fueling. Any time the ECM see the throttle position increase it will increase the rail pressure. Boost or not the rail will come up. Stock chargers will make boost as quick as the pedal goes down, this deleting the fuel rattle created by injector pressure and timing. As mentioned boost eliminates the sound by burning the fuel and creating some heat. ECM timing does not consider the injector size.. Larger stick will derail the regular rate of injection and be dumping more fuel at the same rate as a stock stick. Fuel not being burnt in a cold cylinder or semi warm combustion chamber will simply result in irregular rattle noises.

Eliminating injection events may or may not be the answer.
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So Don's custom box that'll pull the RP down at early throttle and low boost WOULD actually help in this case????

As for the large turbos, Well my old Silver 62 actually spooled a bit slower than my current top with these twins...I know the 480 is kinda large but ......Well , I guess that can't be compared....I didn't have cut pistons and Dual cp3's at that time either....
 
100 thousands would be crazy IMO...I would think 10-20 thou would be the most I would shave off.
Buddy are positive it was 100
 
BTW, The rattle / clatter is there EVEN if the Smarty is completely unloaded and the MP8 completely off..

So I assume it has nothing to do with progamming from the aftermarket since!! Just the stock Dodge crap!!!

Hince the reason I wished I had the $5000 for the Bosch controller!! Ha..
 
onetun said:
100 thousands would be crazy IMO...I would think 10-20 thou would be the most I would shave off.
Buddy are positive it was 100
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Yup!! I told the machinist and picked them up myself....put them side by side.....Like nrussel said....It looked like about 1/8 inch off from the stock one......

If I had it to do over, I wouldn't do quite that much....Theory was , to create clearance for valves with the cam and to make the bottom end Live and last!! Jeff's a big fan of decompression because of the reliability of it!!!
 
ooof....that could be a pile, need calculate this out....I don't think it is as bad as it sounds cause its a 04.5 piston...

Think I'm going to do the 10k bosch....remember need box for tranny too....2k


On edit, whats the compressed thickness of your head gasket? did you use a stock mls?
 
torque beast said:
would changing the spray angle of the injectors help?
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So far, Don's not metioned that as being a possible fix.....

Now that I'm learning more..I don't think it would....It's a decompression thing with the early pilot injection that causing it I think....
 
OK, I think a 24v is 60thou

but roughing it out I think your around 14.52

Bore 4.02
stroke 4.72
Head gasket .060
Deck height .088 ----- normal about 12 thou up - 100 = 88 down the hole
piston top volume 45-8.85 = 36.15 cc's
combustion chamber (valve reliefs) 5.65 cc's

Getting a bit tight here :Cheer: so I'm not betting the farm on those numbers.....
 
Joesixpack said:
OK, I think a 24v is 60thou

but roughing it out I think your around 14.52

Bore 4.02
stroke 4.72
Head gasket .060
Deck height .088 ----- normal about 12 thou up - 100 = 88 down the hole
piston top volume 45-8.85 = 36.15 cc's
combustion chamber (valve reliefs) 5.65 cc's

Getting a bit tight here :Cheer: so I'm not betting the farm on those numbers.....
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Wow!! That's kewl that you know that kinda math!!

Thanks!!

Yeah the 24v gasket at full crush should be right at 58thou. according to what I've learned...

I guess 14.5 is pretty low...
I wonder if I had gone with only 30-40 thou. if I'd have less rattle and still have the reliability from the decompression.....Oh well, maybe on my next build!! lol

For now though, I wanna try to get this as quiet as possible without causing damage...

Thanks again for the math!!
 
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