New Turbo: Help Me Pick One

Hello All,

I have been pondering this for a while and think i am going to go ahead with it, I am looking for advice from all the Turbo Sizing Guru's on what turbo I should pair up with my current GTB2260Vk, The reason i am asking isnt because i want to run a stupid amount of power on the street... I already have traction problems in 2nd as it is.. What i am concerned about is my EGT's. When i lived in Colorado my EGT's RARELY hit off the EGT Hard Cut Mark Malone placed on the car of 950C, but since moving to Florida the spoolup is MUCH sooner and im hitting HIGH EGT's much sooner in the RPM's range.. When the weather is cool outside i dont have a problem with the car hitting peak EGT's and cutting fuel.. but lately with the high 80's days we are having again since moving here.. the car will pull strong and hard a few times in traffic but after a few miles the EGT's are staying pretty high and i hit the 1050C fuel cut limit that is currently set and the car becomes sluggish for a while tell they cool down and then its a never ending cycle. Today i did logs and im seeing timing being pulled literally half the drive from point A to B because of EGT's getting up there.. When the sun sets and the temperatures are in the 60-70's the car pulls like a freight train, but when the sun is out and its 88+ temps outside.. she is struggling..

I am currently only set to peak at 32PSI, so i need more air.. more effeciently..

What turbo would everyone think would match up with the 2260 to just help it out. I know its rated for around 35 in flow.. so maybe a 40-45 size turbo in flow to split the load??

????
GT2871r 44lbs
GT3071r 49lbs

Here is a graph of a recent data log of spoolup.. if that helps with anything.

I did a sizing app to get an idea of what i would want.. and this is what it recommended to me..

Have you tried running a water / meth set up? Helped a friend set one up that on his truck that comes on @ certain EGT temps, and second nozzles when it gets above "X" EGT temp as well (or boost). Think he saw a 200+ degree EGT drop on WOT pulls.

As far as I remember, you have a bigger (S3) intercooler & Darkside boost tubes already.

Would you have the fueling to support a twin turbo set up? I'm all for seeing a twin set of snails on a common rail car!!

TDI-JAY said:

Have you tried running a water / meth set up? Helped a friend set one up that on his truck that comes on @ certain EGT temps, and second nozzles when it gets above "X" EGT temp as well (or boost). Think he saw a 200+ degree EGT drop on WOT pulls.

As far as I remember, you have a bigger (S3) intercooler & Darkside boost tubes already.

Would you have the fueling to support a twin turbo set up? I'm all for seeing a twin set of snails on a common rail car!!

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I thought about that TDI-JAY, but due to the charge pipe facing down, i would be worried about water/meth collecting in the intercooler.. I had a friend with a vette install water meth and due to the jet being installed on the angled slope going into the intake manifold over time he had a puddle in the bottom of his intercooler and one day he got on it and it hydrolocked his engine.. either it pooled up or something failed.. never really found out.. all i know is it hydro locked his engine on a 95+ degree sunny day with no clouds in the sky...i feel like these systems should be used on a setup that isnt in dire need of EGT drops.. as just an adder of extra power.. instead of making a bandaid to a real problem..

Now that i think about it, if i did install one of these setups.. i would probably go through like a gallon every few days.. due to how hight EGT's get during the summer

I dont want to increase boost really tell i get a set of Head Studs in the engine and get some work done to the Cylinder head, i just want to reduce temps and the beauty of Compound setups are that they reduce EGT's by allowing both turbo's to create boost together more effeciently.. Like i said i am not looking to get a ton of power out of this setup.. Thinking i would be happy if i had a reliable 300whp TDI...

Why not have your tune modified to your new location instead?

Get the tune adjusted before worrying about a new turbo.

The only time my EGT's were lower.. was when my tune had more lag and reduced fuelling.. during spoolup... making the car slower and harder to daily drive.. I rather keep the faster spooling and just target the EGT's...

950˚C is 1742˚F. 1050˚C is 1922˚F.

You're supposed to keep temps under 1600˚F, aka ~870˚C else you risk turbo damage.

Because of the denser air in FL and the tune being setup for the less dense air in Colorado, you're now overfueling which is causing your EGTs. Get the tune fixed and stop driving around with a foot through the floor or you'll kill the turbo and then you *will* need a new one.

Digital Corpus said:

950˚C is 1742˚F. 1050˚C is 1922˚F.

You're supposed to keep temps under 1600˚F, aka ~870˚C else you risk turbo damage.

Because of the denser air in FL and the tune being setup for the less dense air in Colorado, you're now overfueling which is causing your EGTs. Get the tune fixed and stop driving around with a foot through the floor or you'll kill the turbo and then you *will* need a new one.

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I don't think that is the real temps...they are rated to...and no I'm not over fueling it.....I have zero smoke...the only time I have smoke is when the vanes fling open when max boost its achieved...and it cut boost quicker than the tune could adjust....

When I was in colorado I put 30k+ running it hard all the way to 950c....

You do know the EGTs get up to 2100f on stock turbo during regen in the summer

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storx said:

Today i did logs and im seeing timing being pulled literally half the drive from point A to B because of EGT's getting up there..

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Its really stuped to pull timing when EGT gets too high. Injecting 2-3 deg later can easily make 30-40° in EGT..

Maybe post a log of railpressure, lambda, boost, EGT, IAT and then you clearly see what the issue is.

With warmer IAT best is to go sooner and increase boost slightly. you will flow the same massflow of air but just require slightly more pressure to get it in the engine as the air is less dense when warmer.

Signing up for more learnins

Votblindub said:

Signing up for more learnins

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Then you're in the wrong place

Storx, you're OUT OF FUEL! push it far enough, limp mode. Keep increasing duration and you'll keep increasing EGTs even with "no smoke" and you won't get any more power out of it.

No amount of additional air will fix your problem.

Jfettig, I thought adding a second turbo to the one I have already...would reduce my EGTs....am I wrong? I'm not looking to push more boost and power tell I get my EGTs under better control....but I would like a second turbo that is capable of getting me to 300 reliably

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You continue to lack the understanding of why your EGTs are so high.

Easy soletion is not throwing a wastgated turbo on there. It will likely make more top end if you have the fuel, but it will sucky as a daily driver.. Easy way out would be to send prodrive a pm and have him make a nice hybrid for you. Fits pnp and might just get the little bit of air you lack to keep egt down at warmer iat's

Hi Rub!! you still messing with these sloooooooooooow diesels lol

Sometimes yep, cant afford the fuel of turbo gasoline cars

JFettig said:

Then you're in the wrong place

Storx, you're OUT OF FUEL! push it far enough, limp mode. Keep increasing duration and you'll keep increasing EGTs even with "no smoke" and you won't get any more power out of it.

No amount of additional air will fix your problem.

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I tend to agree. What would fix your problem is a bigger pump and injectors. The pump is currently under R&D (CP4.2) and there is no option for larger injector bodies at the moment. You have a fuel flow/injector duration problem (too long a duration with not enough flow). No air upgrade including the worlds largest turbo would help this without addressing the root cause.

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See, now I understand what I didn't know...yes I'm no expert...but I'm attempting to learn

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storx said:

See, now I understand what I didn't know...yes I'm no expert...but I'm attempting to learn

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Here's how it was explained to me. Your tune is written to produce A power. To produce that much power the ECU knows that B volume of fuel must be injected per stroke per cyl. That fuel must be injected within a very small window to be effective. That window gets smaller as RPMs go up because no matter what the RPM, diesel fuel only burns at a certain speed. Your injectors cannot flow B amount of fuel within that time window, but the ECU is still trying to get it in, so it increases duration to the point that the end of injection event is past the end of this "ideal" timing window. That's where the EGT rise comes in.

This is an issue with some Stage 2 cars on stock turbos, so I could only see it getting worse with a 2260 because that turbo requires more fuel to spin. I never would have thought of it till someone explained it like I have above.

We all thought injector nozzles wouldn't be our limiting factor when the CRs came out since you can theoretically "inject forever". Turns out that forever isn't what we want because of the above mentioned timing window. Its true NOZZLES aren't the limiting factor here, its the overall flow capacity of the injector bodies themselves. So not so easy of a fix...

The only other option is running higher injection pressures to squeeze a little more flow out, which I doubt the CP4.1 would like since it can't seem to flow enough for a 2260 on stock injectors as it is.

The CP4.2 on the other hand, has been tried and tested in Cummins and Dmax motors at much higher pressures than we run so that may be a viable option. Everything is still in R&D though...

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Lets first see railpressure and lambda and duration to see if the duration really is exsessive or if there is just not enough air.. Even with lambda 1.07-1.1 the cr makes very low smoke, but high egt, when running higher lambda the egt will go down, but you will need to sacrifce power or increase airflow

See these are the things i wish i knew, and i attempt to learn by picking at the brains of others on this forum... I will admit.. i dont know much when it comes to the specifics on how a diesel makes it power... but i am attempting to learn these things so i can make my car more reliable and produce the power i want.

My goals are to make 300whp reliable.. and i hope that isnt to much to ask, as i didnt really know that the actual injectors is holding me back. I have the CP4.2 pump already, I actually plan to take it apart soon to make sure the insides look mint, just waiting on a PM that i asked about on the torque settings of each bolt.. so when i assemble it back together that i have no issues.

So, should i look into new injectors, or work on putting the CP4.2 on??? All i need to install the cp4.2 is a set of new injector lines and T-block to install it.. and figure out how i need to properly time it when putting the timing belt back on.. But i do think i need to run another turbo to make the air i need to reach my ultimate goal correct?

You have excess fuel igniting in your manifold, result high EGT...

You can spray the car with NITROUS, it is safe and will not hurt your motor no matter what people say unless you do a shot that is obviously to much, but a 100hp shot will absolutely hurt nothing and is cheaper and more reliable than all these hybrid-compound-bigger turbos- radiators-etc, think about it 100hp for less than $500, can't beat the bang for the buck, you can spray more if you want, try it out, I DID and DO... YOUR EGT'S WILL DROP BECAUSE THE EXTRA FUEL IS BEING BURNED THUS PROVIDING MORE HP, ALL WHILE THE NX IS COOLING YOUR AIR CHARGE...

Nitrous works great....but at $5 USD/lb. it gets expensive quick. Cheaper to fill yourself using a "mother bottle" at about 1/2 the cost but even that is still expensive if you use it daily...10lb. bottles go quick!

Not practical for fixing this problem longterm IMO

vwracer said:

You can spray the car with NITROUS, it is safe and will not hurt your motor no matter what people say unless you do a shot that is obviously to much, but a 100hp shot will absolutely hurt nothing and is cheaper and more reliable than all these hybrid-compound-bigger turbos- radiators-etc, think about it 100hp for less than $500, can't beat the bang for the buck, you can spray more if you want, try it out, I DID and DO... YOUR EGT'S WILL DROP BECAUSE THE EXTRA FUEL IS BEING BURNED THUS PROVIDING MORE HP, ALL WHILE THE NX IS COOLING YOUR AIR CHARGE...

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For the strip maybe, for a daily? Waste of $$$$.

How about propane injection?

Votblindub said:

How about propane injection?

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CNG is better than LPG since it's less prone to detonation (higher MON)..

However both are still fuels getting injected into the intake which could mean challenges as far as timing goes.

CNG would solve the extra fuel issue but it is a hefty cost upfront and big tank in the trunk. It is cheap as far as fuel goes though...

Well, I contacted a few people on info on getting the last of the parts i need to put the CP4.2 pump on.. hopely i can get it on within the next month.. and start tuning it..

Can we get back on topic what second turbo should i go with.. once i get the new pump on and fix my EGTs??