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WVRigrat05

WVRigrat05

Wound for sound
Jan 1, 2011
3,081
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36
French Creek, West Virginia
I put synthetic oil in mine right off the bat and it had a fair amount of blow by, builder had me dump it and I put rotella in and babied it for 150 miles, changed it again and ran the dog **** out of it and smoked my trans, 1500 miles total, then I went to synthetic oil, and had little to no blow by.
 
LBZ

LBZ

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Jul 2, 2007
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I started with 15w-40 and zinc for 250 miles. Oil pressure is steady at 35 psi at 1700rpm so not too worried anymore.

PTW was. 0005" over what Mahle recommended for cast race. Grade C gasket, , 025" top,, 020" bottom on the rings.
 
Chevy1925

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
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LBZ said:
I started with 15w-40 and zinc for 250 miles. Oil pressure is steady at 35 psi at 1700rpm so not too worried anymore.

PTW was. 0005" over what Mahle recommended for cast race. Grade C gasket, , 025" top,, 020" bottom on the rings.
Click to expand...

wow thats a loose top ring, sure its not 20 top and 25 bottom?

35psi at 1700rpm is low as well. spec its 1800rpm 42psi MIN. oil temp might be getting up there, hence the lower pressure
 
Dozerboy

Dozerboy

Well-known member
Jun 23, 2009
4,892
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TX of course
Not sure what you got on there for a trailer but I wouldn't call 9 horrible on a new engine. Ive never gotten better then 11 towing the way I drive and that was probably CA with a 55mph speed limit.

I agree with james about boost. Only use target for fine tuning you have to get the boost table close first. You might be requesting to much boost at cruising speeds. Your EGTs sounds low since your towing. The vane % on your log is just as good as a BP gauge to tell you if your asking for to much boost or not. I haven't played with my 3794 enough to know where they run. I have a feeling messing with the boost isnt going to net you much mileage though. So if your content with your EGTs just wait on boost.
 
LBZ

LBZ

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Jul 2, 2007
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Chevy1925 said:
wow thats a loose top ring, sure its not 20 top and 25 bottom?

35psi at 1700rpm is low as well. spec its 1800rpm 42psi MIN. oil temp might be getting up there, hence the lower pressure
Click to expand...
Right. Got dyslexic on the numbers.
Oil temp is between 210 and 220. It's a couple pounds below spec at 1800 on synthetic oil. It's at 18-19 so good on hot idle spec.
 
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LBZ

LBZ

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Jul 2, 2007
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Dozerboy said:
Not sure what you got on there for a trailer but I wouldn't call 9 horrible on a new engine. Ive never gotten better then 11 towing the way I drive and that was probably CA with a 55mph speed limit.

I agree with james about boost. Only use target for fine tuning you have to get the boost table close first. You might be requesting to much boost at cruising speeds. Your EGTs sounds low since your towing. The vane % on your log is just as good as a BP gauge to tell you if your asking for to much boost or not. I haven't played with my 3794 enough to know where they run. I have a feeling messing with the boost isnt going to net you much mileage though. So if your content with your EGTs just wait on boost.
Click to expand...
30' tandem axle Toy Hauler
I'm just going by what I used to get as reference. I don't recall it ever that bad pushing a headwind even.
 
LBZ

LBZ

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Can someone have a look at my tune I posted a few posts back and maybe tell me why my rail pressure goes to 75mpa on cold starts? It should only be about 35. When it warms up it's fine. I'm missing something.
 
Chevy1925

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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LBZ said:
Right. Got dyslexic on the numbers.
Oil temp is between 210 and 220. It's a couple pounds below spec at 1800 on synthetic oil. It's at 18-19 so good on hot idle spec.
Click to expand...

ok, still loose on ring gap tolerances for best chance at no blow by and good mpg but not a deal breaker either. i have a feeling you might have a combo of things, some you can change, others you cant without pulling the engine. piston protrusion would be good to know here.

synthetic shouldnt affect your pressure and at 220*, thats not going to net you a big enough drop in oil pressure to put you at 35psi. if you can get your bearing clearances for us, that will tell us some of the story as well.

i need to check but i dont think the oil squirters on those pistons are opening at 35psi. I cant remember if its 39 psi or 29 psi they open. ill do some looking here
 
Chevy1925

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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Phoenix Az
LBZ said:
Can someone have a look at my tune I posted a few posts back and maybe tell me why my rail pressure goes to 75mpa on cold starts? It should only be about 35. When it warms up it's fine. I'm missing something.
Click to expand...

i think thats a hard part issue. im not seeing anything in there to make it change in comparison to a stock LBZ tune. the mulitiplier doesnt even let it go that high and the hard limit for the rpm is 70 mPa

LBZ said:
.012" protrusion I believe
Click to expand...

ok, so your kinda on the looser side with the C gasket but you have valve reliefs. between those and the looser ring gap, i can see some loss there for MPG but will help you if your after lots more power.

ill bet you can run more timing than i could without rattle due to the pistons and valve reliefs. see at what point you get injector rattle in the cruise area.
 
LBZ

LBZ

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I wonder if it's not the fpr? I've never adjusted it and it's a Danville modified cp3. Not sure why it would only do it when cold if it was a hard part.
 
Dozerboy

Dozerboy

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Jun 23, 2009
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As for the cold starts what is the weather like up there now? Are you getting and rattle etc at start up?

Sent from my SAMSUNG-SM-G900A using Tapatalk
 
Awenta

Awenta

Active member
Sep 28, 2014
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CT
Chevy1925 said:
ok, still loose on ring gap tolerances for best chance at no blow by and good mpg but not a deal breaker either. i have a feeling you might have a combo of things, some you can change, others you cant without pulling the engine. piston protrusion would be good to know here.

synthetic shouldnt affect your pressure and at 220*, thats not going to net you a big enough drop in oil pressure to put you at 35psi. if you can get your bearing clearances for us, that will tell us some of the story as well.

i need to check but i dont think the oil squirters on those pistons are opening at 35psi. I cant remember if its 39 psi or 29 psi they open. ill do some looking here
Click to expand...
Almost positive it's 29 (27?)
Not upper 30s

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NC-smokinlmm

NC-smokinlmm

<<<Future tuna killer
May 29, 2011
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At Da Beach
Pull an oil sample. It will tell you whats going on. Have you done a mechanical oil pressure test yet? Your truck sat for a long time, sensors dont like that.
 
LBZ

LBZ

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Jul 2, 2007
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Dozerboy said:
As for the cold starts what is the weather like up there now? Are you getting and rattle etc at start up?

Sent from my SAMSUNG-SM-G900A using Tapatalk
Click to expand...
No rattle. The usual smoke and a little lope due to no intake heater and bigger nozzles with an untouched pw table. Around 10C in the morning. I'll let you figure out what that is in F America!
 
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