Another T4 thread

ja_cain · Nov 13, 2016

I think the problem with the 38r might be the exhaust side. That's probably why the more aggressive wheels don't do well with towing/dd from 2200 down lower. Some of the wheels are more aggressive, thus requiring a more efficient exhaust side to compensate for this. It would be interesting to put a speed sensor on these troublesome turbos.

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Countrycar · Nov 13, 2016

ja_cain said:
I think the problem with the 38r might be the exhaust side. That's probably why the more aggressive wheels don't do well with towing/dd from 2200 down lower. Some of the wheels are more aggressive, thus requiring a more efficient exhaust side to compensate for this. It would be interesting to put a speed sensor on these troublesome turbos.

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That's exactly what Matt said, "The problem being the exhaust side of the 38r".
To bad the 38r doesn't have a port/Sensor on them.

Countrycar · Nov 13, 2016

TyCorr said:
Shti gentlemen, 35s are the smallest tires i have ran.

If your idle cant be refined, you have shti injectors or a tuner that needs to hang it up. Im doubting that gh needs to quit tuning lol.

My truck is great. Im glad i dont have all these issues. Especially since it sat alot the last two years. UNtil this summer.

I actually suspected an injector issue earlier this year, so I removed all 8 injectors and sent them back to Nate for inspection. He went thru them checked them, flowed/Balance and sent them back, no issue's. And well we all know Matt's rep too. So I'm kinda with you on perhaps an oil issue. All my parts here are new, bts kit/new pumps/ ipr/icp etc. So yeah it is a pain in my butt right now trying to figure this out. The only part on my entire build that isn't new is the crank & and the turbo. LOL So yeah it does suck, but I'll get it sorted sooner or later. I'm not one to give up. :thumbup:

Z_racing14 · Nov 13, 2016

I still have a 1.15 exhaust housing for the 38r if anyone with bigger injectors wants to give a try. I remember Charles saying he liked the turbo a lot better that way

ja_cain · Nov 13, 2016

Countrycar said:
That's exactly what Matt said, "The problem being the exhaust side of the 38r".
To bad the 38r doesn't have a port/Sensor on them.

The sxe turbos have provisions for the speed sensor, the last time I checked.

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mikeeg02 · Nov 13, 2016

hucorey said:
I never had huge egt issues with my old 250/200's and a Garrett GTP38R, but BP was a bit much. I also am running a GH STG1 cam. Swapped in the KC38R a year ago. BP:Boost, dang near 1:1 ratio at WOT. Actual #'s were 39 boost 41 bp. I had the gate set to fully open at that boost level.

I dropped down to 230/100's and last time I towed was 8k (nothing terrible obviously), running 35's and 3:73's (definitely not ideal), and pulling fairly steep grades with OD off and never seen above 1100.

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Curious. How much pulse width was in the tune that test done in ? And how long a duration was the test with happy egts? Not being facetious. Honest curiosity.

Countrycar · Nov 13, 2016

Z_racing14 said:
I still have a 1.15 exhaust housing for the 38r if anyone with bigger injectors wants to give a try. I remember Charles saying he liked the turbo a lot better that way

I wouldn't mind give it a try to see if changes anything for my setup.

Countrycar · Nov 13, 2016

ja_cain said:
The sxe turbos have provisions for the speed sensor, the last time I checked.

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To bad I didn't think of buying one earlier Doh.....:slap:

ja_cain · Nov 13, 2016

Countrycar said:
To bad I didn't think of buying one earlier Doh.....:slap:

It's all good. Lol! Only a nerd like me would bother to know that kind of stuff. That being said, I really appreciate you sharing your experiences!

I can't wait to see how the KC turbos based on the sxe line perform. I really think these could be a game changer if they get the exhaust side correct.

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The Brad · Nov 13, 2016

Countrycar said:
Thanks Ty for your input here as well. When Brad comes out, he's gonna bring his AE program and plug in to see how everything is working. I don't know much to very little myself about tuning, but maybe Brad can take a look and see if there's anything suspicious that might be causing me problems.

Just so we're clear, I can't even tune a guitar.

hucorey · Nov 14, 2016

mikeeg02 said:
Curious. How much pulse width was in the tune that test done in ? And how long a duration was the test with happy egts? Not being facetious. Honest curiosity.

I honestly don't know, except it was a very old Race tune I was towing in.

I was in the foot hills of the Rockies for about a 2-3 hrs up n down the local State highways. So probably nothing too extended am out of hill climbs like an interstate.

I left it in OD quite a few times just to see what EGTs would be and a couple times they got into the high 1400 mark but that usually when was as I was just getting to the top. When shut off the OD, temp shot right down to 900-low 1100ish.

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TARM · Nov 15, 2016

TO have high egts or any relative egt temps its not just air its fuel and air. WE can tune fuel very precisely compared to air. If you have egt issues and everything is in proper working order its a fueling issue thus tuning. You can hold proper egts with a stock turbo and 400% nozzles with the proper tuning.

Think about it if a 400% can be tuned to idle then anything off idle is using more fuel thus......... IF it can handle the resolution to get a smooth idle then you can cut fuel back enough for any amount of air over that under a load.

EGTS are a fueling issue and thus a tuning issue if everything is in proper working order. If you have a 38R and 1400 EGTs then going to a turbo moving more air and egts goes down it proves my point. The fuel tuning was too heavy for the air curve of 38R. As tuning is something that does not take tearing into your engine it seems a way better choice.

Now do not get me wrong more air is of course better for more power and if it spools up better great but its not what should be used as a way to address egts. Thats tuning

The Brad · Nov 15, 2016

I wouldn't argue with that logic, but in my case, the only way to keep egts in check while towing was to pull fuel to the point that I had less power than I did with ADs and a stock turbo. Besides, shouldn't a 38r be able to take whatever my puny 200/80s can spit out within 3.2 milliseconds?

cjfarm111 · Nov 15, 2016

Swaan · Nov 16, 2016

Tuning is not going to fix a turbo that dont flow worth a **** below 2000 rpm. Just for an example.
If your turbo is a turd down low and your pulling fuel to compensate ,perty soon you got a truck that wont pull any better then a 6.9 idi. But hey, at least your egts are in check right. Lmao!!

cjfarm111 · Nov 16, 2016

My thoughts exactly.

V-Ref · Nov 16, 2016

I wish my Unlimited 200% nozzles inj truck started idled ran and towed worth a damn in temps from -35 to 80F.

Oh wait...it does.

Lots of "experts" on here...Sorry to break it to the "experts"....but tuning does matter

mandkole · Nov 16, 2016

Swaan said:
Tuning is not going to fix a turbo that dont flow worth a **** below 2000 rpm. Just for an example.
If your turbo is a turd down low and your pulling fuel to compensate ,perty soon you got a truck that wont pull any better then a 6.9 idi. But hey, at least your egts are in check right. Lmao!!

Agreed... lots to this issue, not just 'fuel and air'.

I live with this every time I tow. Its not an issue of making power (theres plenty) or having sh!tty tunes, but the transient response when under load. This is difference in the driver experience. I ve learned to drive it safely (engine rpm the key) but it takes effort. You don't just get in and rock up and down hills, ignoring the EGT gauge.

Do I dislike the 42? I would if I towed 8-10K all the time... Decide what you will do with the truck most of the time, then live with its short comings the rest of the time.

The Brad · Nov 16, 2016

mandkole said:
Decide what you will do with the truck most of the time, then live with its short comings the rest of the time.

...or go with compounds!

V-Ref said:
I wish my Unlimited 200% nozzles inj truck started idled ran and towed worth a damn in temps from -35 to 80F.

Oh wait...it does.

Lots of "experts" on here...Sorry to break it to the "experts"....but tuning does matter

Tuning is definitely important, especially the bigger the nozzle, but how do you tune to make a turbo move more air at 2000rpm with out raising the EGTs?