Detuning large injector nozzles - How to pick injector size for upgrades!

The Brad

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During live tuning, the fuel was pulled and I do have tunes that run clean, but the power didn't exist below 2500 without high EGTs. I'm not talking window the block power. One thing I didn't do was let the WG open. I was told by many to keep it cranked shut. When I pulled the 38r, there was a clean spot under the gate. Wish I would've tried that.

I have 910s and Smith Bros push rods. Stock push rods were straight when I pulled them. Did you see the screen shot I added in the T4 thread showing the temp spread between IAT and MAT? I think that tells a lot.

I didn't think 200/80s could "max out" a 38r.
 

TyCorr

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During live tuning, the fuel was pulled and I do have tunes that run clean, but the power didn't exist below 2500 without high EGTs. I'm not talking window the block power. One thing I didn't do was let the WG open. I was told by many to keep it cranked shut. When I pulled the 38r, there was a clean spot under the gate. Wish I would've tried that.

I have 910s and Smith Bros push rods. Stock push rods were straight when I pulled them. Did you see the screen shot I added in the T4 thread showing the temp spread between IAT and MAT? I think that tells a lot.

I didn't think 200/80s could "max out" a 38r.

They cant. They barely will make 500hp without super long pw. Theres more to tuning than max hp. Im sure you understand that but my point is you guys were having issues faaaaar below that point.

I hate to keep saying it but ive ridden in quite a few modded 7.3s that the owner thought was fine and they werent.

We wont come to agreement on this simply because our individual experiences but i can assure you that my experience with your injectors would have been vastly different as it is with 250/200s.

Im glad you got it lined out though.
 

TARM

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The people that say keep wg shut do not understand how turbos work or that the real effect of a properly tuned waste gate is to keep it inside the sweet part of the compressor map. Why would someone want to just make higher boost at the cost of more heat and thus less O2 density and therefore less actual power? But you do get higher egts and smoke so. I know smoke use to be all the rage with the teenagers and early 20s yr olds.
 
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Jomax

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The people that say keep wg shut do not understand how turbos work or that the real effect of a properly tuned waste gate is to keep it inside the sweet part of the compressor map. Why would someone want to just make higher boost at the cost of more heat and thus less O2 density and therefore less actual power? But you do get higher egts and smoke so. I know smoke use to be all the rage with the teenagers and early 20s yr olds.


There's some 20 year olds that hate it. Lol me included.

Learned something, everyone always said to crank the WG shut on the 38r?


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lincolnlocker

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There's some 20 year olds that hate it. Lol me included.

Learned something, everyone always said to crank the WG shut on the 38r?


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with smaller injectors yes.. but usually needs tuned for optimal performance

live life full throttle

god bless america and the farmer who feeds your fat ass
 

TyCorr

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Yea. Cranking it shut is fine on an 80 or 100 percent nozzle. But a bigger nozzle will blow that ***ker open if you pour the hot, hot coals to it. If you try to do that on mine it'll start blowing through the gate at 28psi. If adjusted it'll make about 32psi in lighter tunes but in the hotter ones despite the gate opening it'll creep up to about 36psi yet the gate is still keeping bp in check. I drilled my turbine hsg so it pulls from both volutes. My back pressure is 1:1 until 30 psi. But i also dont have egt issues. Well besides finding gauges that arent garbage.

If some of you guys are using autometers you might not even have high egts but the gauge is saying you do.

I did some searches and as I have been saying for the last five years their quality control and such is so bad that tons of people are wondering how they have 600 degree egts at ***kin idle. Mine you could wiggle the wires on the gauge and it'd go from 500 to 275 at idle. I can see less gands on owners being confused and assuming their egts are 1200 degrees at 65mph.
 

TyCorr

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In other words if your truck runs well and has power without blacking out everything to your right, your readings may be off.

Sometimes its good to use ones head and just evaluate things outside the gauges. Is the truck running well? Check. Is it smoking alot? No. Is the power smooth and responsive? Check. So maybe my pos chinese autometer sensor isnt telling the whole story.
 

Countrycar

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Yea. Cranking it shut is fine on an 80 or 100 percent nozzle. But a bigger nozzle will blow that ***ker open if you pour the hot, hot coals to it. If you try to do that on mine it'll start blowing through the gate at 28psi. If adjusted it'll make about 32psi in lighter tunes but in the hotter ones despite the gate opening it'll creep up to about 36psi yet the gate is still keeping bp in check. I drilled my turbine hsg so it pulls from both volutes. My back pressure is 1:1 until 30 psi. But i also dont have egt issues. Well besides finding gauges that arent garbage.

If some of you guys are using autometers you might not even have high egts but the gauge is saying you do.

I did some searches and as I have been saying for the last five years their quality control and such is so bad that tons of people are wondering how they have 600 degree egts at ***kin idle. Mine you could wiggle the wires on the gauge and it'd go from 500 to 275 at idle. I can see less gands on owners being confused and assuming their egts are 1200 degrees at 65mph.
Ty, where is the advantage to drilling the turbine housing, and did you see any changes when you did this? Trying to learn about this is all. Thanks.
On Edit: Any pictures on how to do this?
 
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TyCorr

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The 38r only bleeds excess bp off of the pass side bank of cylinders. The other bank feeds the inner volute. It seems to keep backpressure in check better since i dontbgave crazy high backpressure with 250/200s.
 

ja_cain

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Politics are gay. You guys are gay. Lol! ;) Awesome info on proper gate function btw!

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TyCorr

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Politics are stupid. But Im all in on this Trump bidness and I should NOT be. Im back in the highest paid ironworkers local on the planet and he should be my enemy. But we need a drastic approach. He's got the right advisers and ideas. Hevs being attacked so voraciously because he's going to upset the gravy train.


Lots of good labor hands that dont support the democratic victims party anymore.

Sidenote:I picked up valvoline maxlife 15w40 oil for 10.99 a gallon yesterday. I put my trans in August 2nd and reassembled my engine (fuel system, turbo, intercooler, etc). I bought 25 gal of warren petroleum 15w40. I ran 4 gal through the truck for 500 miles. Drained. Ran another 1500. Drain. This last change i did on 10/14. Then i did it two weeks ago. Got a new job and im driving to chicago everyday. Ive put 2550 on the truck in ten days. Today i changed the oil with a gold fram filter and the 4 gal of valvoline maxlife. I started the truck to check for leaks and it mitigated half of my hot injection system and its operating noise. :eek:

Ill keep y'all updated on it.
 
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ja_cain

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Politics are stupid. But Im all in on this Trump bidness and I should NOT be. Im back in the highest paid ironworkers local on the planet and he should be my enemy. But we need a drastic approach. He's got the right advisers and ideas. Hevs being attacked so voraciously because he's going to upset the gravy train.


Lots of good labor hands that dont support the democratic victims party anymore.
I hear you. Washington definitely needs a nice swift kick in the nuts.

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TyCorr

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I edited. Sorry buddy. Lets talk about oil instead.

Im three months sober from all social media because im a trump supporter. I was slandered attacked and called a nazi because i dont support a nanny state and turning the US into a third world warring country.
 

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