Which turbo setup for HPDE? Wider powerband possible (Good responsiveness with a decent top end)

Turbo setup options

  • Speedtech with GTX3071

    Votes: 0 0.0%
  • Speedtech with GTX3576

    Votes: 2 20.0%
  • Doc Race bottom mount with PTE 5862

    Votes: 0 0.0%
  • RB Game finishers High Flow

    Votes: 6 60.0%
  • Keep my ADE Kit

    Votes: 1 10.0%
  • Another different of exposed options (please post which)

    Votes: 1 10.0%

  • Total voters
    10

CAA

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Sep 13, 2017
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Hello everyone,

As I said, I'm searching for a wider powerband setup because I will use the car a few times of year, especially for hard track abuse.
I have installed an ADE 6266 since some years ago, when I used the car in a entirely different way of my current purposes. I'm not seeing full boost until 4k rpm or a bit more, so a powerband from 4 to 7k rpm it's not the best on slow turns and trying to deal exit them with very low power or with a lower gear at very high rpm. So my goal would be 500whp on straight 98RON (equivalent to 93oct there in US) in a setup that reach full boost at 3k with a decent top end, and at the same time trying to avoid undesirable choking effects at high rpm of a smaller turbo setup.
After doing some research, this is the best options I think that I should consider, but I would appreciate if someone post his opinion or propose another good options:

- Speedtech with GTX3071 (T3 divided; 0.83AR).
This is my one of my favourite options. Speedtech is very good kit with unbeatable price. Install seems to be pretty straightforward and they don't lock to buy the whole kit, so I can re-use my Tial wastegate and buy the turbo in EU to avoid pay more than necessary customs fees.
Regarding from the Turbo, user r0nd3L posted a log with this same setup and reach full boost (19 psi) at 3150 rpm. This is pretty at the point I want the boost threshold, but I don't sure if the top end would be enough to prevent to go beyond the choke line and produce the undesirable effects of a massive heat.

- Speedtech with GTX3576 (T3 divided; 0.83AR).
This is another good option. It's a little the opposite of the previous option, worse spool but better top end. User nahor posted a log reaching full boost (19 psi) approximately at 3.5k rpm with high ethanol blend. Spool is a little above that I like, but probably with tune changes it could spool sooner, and I'm pretty sure won't be beyond the choke line at the top end, so it's a more reliable option than 3071.

- Doc Race bottom mount with PTE 5862 gen2 BB (1.05A/R).
It's not my favourite option because is not a divided manifold and they lock to buy their whole kit and a Precision Turbo. I don't rely much on a non-water cooled turbo for HPDE. Anyway, it's a considerable option.
I don't have the idea where the boost threshold would be with this setup, but if my 6266 BB on a tubular manifold reach full boost at 4k rpm, this option will spool quicker definitely.

CES is a great kit but paying additional 2 grand for a trimmed piece of metal is out of my budget.

- RB Game finishers High Flow.
This is another of my favourite options, in a opposite way of the others as it's a twin setup. 650-700whp capable setup with a great spool as any twin setup. I seen few dynos where they are making max torque at 3k rpm approximately. I think that 500whp will not making them pushing hard and generating too much heat. It's the only Twin setup I consider to buy because although there are other twin options with similar or even higher whp capability they have a large history of reliability complaints.

- Keep my ADE Kit lowering the AR of my 6266 or swap a smaller turbo.
As a said above, not the best for track purposes because of the narrow powerband (as the most of single kits).
I think that I could pick some boost with a few hundred less rpm if I switch my 0.84AR turbine housing to a 0.63 AR that I seen is available for a 6266 BB. Another option is directly to switch to a smaller turbo, but at the end, is a heavy tubular undivided T4 manifold with a turbo in a very low position that has poor gravity for oil drainage, less than ideal for track racing.

As I said, any input would highly appreciated.

Regards
 

r0nd3L

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Dec 2, 2019
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I can provide slightly more input on my setup. I'm running 20PSI on 93 Oct. Car is responsive, but IMO, lacks power. It traps 120MPH and does maybe 8.5s 60-130. Anything higher than 20PSI, I notice IATs start climbing rapidly which will probably not be ideal for extended track use. I know some folks are running 3076 with good results, but I'm not sure spool would be any better than 3576. I'd also consider using proper gearing so you are always in powerband. I will be installing 3.46 instead of stock 3.08, for example, just to be able to handle super low speed 2nd gear turns better.
 
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nahor

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Sep 15, 2017
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User nahor posted a log reaching full boost (19 psi) approximately at 3.5k rpm with high ethanol blend. Spool is a little above that I like, but probably with tune changes it could spool sooner
Just wanted to confirm, there is definitely more left on the table with the tune regarding the logs I posted. My VANOS tables are still completely stock and I haven't had a chance to mess around with spool mode too much yet either. It was still just open loop boost control as well, so probably a bit of spool to be picked up there as well.
 
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iminhell1

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Jun 17, 2018
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Why wouldn't you just swap the turbo you have for something else? Or swap the turbine for a smaller A/R to increase spool? Why make things more difficult than they have to be?
 
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CAA

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Why wouldn't you just swap the turbo you have for something else? Or swap the turbine for a smaller A/R to increase spool? Why make things more difficult than they have to be?
Is one of the options listed above.

I have to admit that is the less desirable option, even less than DocRace option. Reasons, as said, is a T4 undivided heavy tubular manifold. More laggy than a log manifold (as other kits listed). Position of turbo is at very low point so gravity for oil drain is not ideal. I don't know if I can put another different turbo than a Precision without modifying the downpipe flange, and if I keep with a Precision I don't rely much on a non watercooled for HPDE purposes.
Don't want to misunderstand me, ADE is a great kit, quality is top notch, and it could do great high numbers, but is less ideal for another purposes like I'm searching.
 

iminhell1

Sergeant
Jun 17, 2018
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Unless you go BW, downpipe should not change much. Maybe 1/4" up/down/in/out. Basically not a sticking point.
Divided vs undivided is marketing. Once you look at turbine tip speeds vs exhaust speeds you'll see this. undivided opens up the use of lighter housings also (cast SS).

You can add water cooling to what you have. Just need to remove the block plugs and make some hoses. Not a big deal. If you want to go to a Garret or VS turbo.

And your deal with RPM, that's a driver mod you need to do. You not wanting to shift is costing you how much money? Learn better throttle control, get a better tune to act more natural, get a better tune in general, etc. You would be amazed at what a few simple changes in a tune can do. And it's the cheapest option.
The vast majority of tunes/tuners really only do WOT tuning. There isn't much time spent on transient fueling, throttle feel, power delivery. Granted some do better than others. But to get a perfect to you tune, I think you need to be the one making the changes, or the tuner needs to be in the car with you and also a seasoned HDPE driver.
 
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fmorelli

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Tune ... and IMHO you are going to find your suspension has more to do with your HPDE, in my opinion. It's a bunch of power to put down and manage, for the suspension, and the driver.
 
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rac

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Nov 14, 2016
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So how many seasons, hours on track has the current set up done?

I ask because I made a lot of poor decisions early on when deciding on my car as a track hobby and wasted a lot of money on things that were not necessary.

I'm surprised you need full torque below 4k. Often full torque at 3k actually becomes counter productive with experience, moreover the reliability of the twin wastegate system and overall system sensitivity at low rpm makes putting that torque down safely difficult and sometimes dangerous. i was beat out of corners many a time by naturally aspirated vehicles when i had stock twins and all the torque you could want at minimum corner rpm. managing your traction circle is hard work when you have sudden hard torque come in while still generating lateral g's. so ok, you can partially address that with throttle and boost target mapping, but at some point your nullifying the main advantages of the chosen set up and back to power delivery more similar to your current set up after spending a sh8t load of money.

secondly you are after a lot of reliable power on crap fuel (no meth, no water?) for extended use, and also want a more responsive set up. these two things are a direct compromise.
for the longevity of your track experience you want to have as free flowing hot side as possible/practical.

so my 2c is;
- assess your corner speeds with some basic logging software / apps,
- improve that - driver experience, tyres, suspension etc, evaluate your g-g plot (rarely more torque at low rpm is going to make you significantly faster around a proper circuit when you are really critical on your data, you will find a lot more low hanging fruit than that)
- reassess optimal gear selection, potential differential ratios
- then determine if you really need a more responsive set up
- then if you still feel that way step down the existing turbo (and at this point the 6266 will have had enough track hrs to justify to you whether or not pte turbo is reliable enough on this kit - which potentially gives you the most cost effective changes you might be able to make, like a 6062 for instance).

not the feedback you want but just trying to practically save you money and get bang for buck. spend enough time on a racetrack and you will find plenty of other places to drop your $$.
 

CAA

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Tune ... and IMHO you are going to find your suspension has more to do with your HPDE, in my opinion. It's a bunch of power to put down and manage, for the suspension, and the driver.
Thanks for your input.
Absolutely in agreement. I'm doing also the whole setup for HPDE purposes (F8x full brake setup, KW clubsport 2 way, clutch LSD, adjustable control arms, solid bushings, etc.), but in this post my objective is to find inputs to decide the better balanced turbo setup. Absolutely in agreement also regarding in driving abilities.
 

CAA

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Sep 13, 2017
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So how many seasons, hours on track has the current set up done?

I ask because I made a lot of poor decisions early on when deciding on my car as a track hobby and wasted a lot of money on things that were not necessary.

I'm surprised you need full torque below 4k. Often full torque at 3k actually becomes counter productive with experience, moreover the reliability of the twin wastegate system and overall system sensitivity at low rpm makes putting that torque down safely difficult and sometimes dangerous. i was beat out of corners many a time by naturally aspirated vehicles when i had stock twins and all the torque you could want at minimum corner rpm. managing your traction circle is hard work when you have sudden hard torque come in while still generating lateral g's. so ok, you can partially address that with throttle and boost target mapping, but at some point your nullifying the main advantages of the chosen set up and back to power delivery more similar to your current set up after spending a sh8t load of money.

secondly you are after a lot of reliable power on crap fuel (no meth, no water?) for extended use, and also want a more responsive set up. these two things are a direct compromise.
for the longevity of your track experience you want to have as free flowing hot side as possible/practical.

so my 2c is;
- assess your corner speeds with some basic logging software / apps,
- improve that - driver experience, tyres, suspension etc, evaluate your g-g plot (rarely more torque at low rpm is going to make you significantly faster around a proper circuit when you are really critical on your data, you will find a lot more low hanging fruit than that)
- reassess optimal gear selection, potential differential ratios
- then determine if you really need a more responsive set up
- then if you still feel that way step down the existing turbo (and at this point the 6266 will have had enough track hrs to justify to you whether or not pte turbo is reliable enough on this kit - which potentially gives you the most cost effective changes you might be able to make, like a 6062 for instance).

not the feedback you want but just trying to practically save you money and get bang for buck. spend enough time on a racetrack and you will find plenty of other places to drop your $$.

I really appreciate your detailed input.

I made several times spirit driving with this setup as well as with stock twins, but I didn't track this car yet. I know that spirit driving is very little comparable to a track experience (I tracked another previous cars, I know it well), but even with making spirit driving, such as driving fast on hill climbing roads, I feel this setup very laggy in some situations as I previously stated, comparing it against with stock twins I really miss the inmediately responsiveness of them, especially exiting turns. So, spinning this in my head these last days, I think that a better balanced setup with wider powerband would be more useful, something in the middle point of stock twins and my current setup, and as I have the subframe enterely removed for making oil pan gasket and oil pan baffle, removing turbo would be additional 1 or 2 hour.

I assume that I would lost some money swaping the turbo setup but I would sell my ADE Kit so I'm think I will recover a good part.

Regarding for the cooling and fuel. Actually have installed two 25 row oil coolers (parallel plumbing, not in series), CSF water radiator, two additional small water radiators, a Setrab core for AT cooling with a Mishimoto 70ºc tstat, as well as 7,5" BMS Race Intercooler (HD core). I think that making 500whp the heat issue chance is unlikely, but if it would be an issue, could I put one or two bungs on my chargepipe and spray some water/meth blend. I don't have E85 acces on my country, unfortunately.

Anyway, your inputs makes me rethink seriuously to stay with my current setup. I will decide in next days what I'll do.
 
Jul 30, 2018
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Regarding for the cooling and fuel. Actually have installed two 25 row oil coolers (parallel plumbing, not in series), CSF water radiator, two additional small water radiators,.

Please can you give more details about 2 small water radiatora? Please pictures if it is possible. Thank you.
 

rac

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Nov 14, 2016
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I really appreciate your detailed input.

I made several times spirit driving with this setup as well as with stock twins, but I didn't track this car yet. I know that spirit driving is very little comparable to a track experience (I tracked another previous cars, I know it well), but even with making spirit driving, such as driving fast on hill climbing roads, I feel this setup very laggy in some situations as I previously stated, comparing it against with stock twins I really miss the inmediately responsiveness of them, especially exiting turns. So, spinning this in my head these last days, I think that a better balanced setup with wider powerband would be more useful, something in the middle point of stock twins and my current setup, and as I have the subframe enterely removed for making oil pan gasket and oil pan baffle, removing turbo would be additional 1 or 2 hour.

I assume that I would lost some money swaping the turbo setup but I would sell my ADE Kit so I'm think I will recover a good part.

Regarding for the cooling and fuel. Actually have installed two 25 row oil coolers (parallel plumbing, not in series), CSF water radiator, two additional small water radiators, a Setrab core for AT cooling with a Mishimoto 70ºc tstat, as well as 7,5" BMS Race Intercooler (HD core). I think that making 500whp the heat issue chance is unlikely, but if it would be an issue, could I put one or two bungs on my chargepipe and spray some water/meth blend. I don't have E85 acces on my country, unfortunately.

Anyway, your inputs makes me rethink seriuously to stay with my current setup. I will decide in next days what I'll do.

so in that case i really think you need to get out to your chosen track and get the data you need before spending more money.
there are any number of issues that might come up out of left field and cause you to rethink the whole damn thing.

i know what you a fear i have been down both paths. dont assume what the current setup will feel like until you get a lot of laps under your belt and dont install the LSD yet either. you might find a minor change in differential ratio's reduces the overall number of shifts you need to make and you could make that call after your baseline data and then set up the LSD with an optimal diff ratio.

with regards to heat, water and oil is one thing, the other thing is in cylinder combustion temperatures and detonation. high boost, high back pressure, low rpm torque is all stuff more likely to go "pop" . so what i am getting at, you might find the current set up only needs a minor improvement in lower rpm torque, any maybe that can be resolved with a minor turbo change or diff ratio change before going and doing something more dramatic that you didn't need to do.
 
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135i2

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Jul 23, 2017
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I completly agree with what rac has said. There is plenty of optimisation to chase before the expense of kit and turbo swaps. A twin scroll setup may gain you a possible 500-600rpm with the same turbo. Plenty of articles and data around on twin scroll vs single scroll. The ADE is a good, free flowing manifold. If you must change something like your turbo, a water cooled Gen 2 3076 or 3576, G30-900 or G35-900 may assist.
 
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Asbjorn

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Mar 10, 2018
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N54 + 500whp + RON98 + track driving is a big no no unless its a massive turbo. I can sort of support the setup you are proposing If its a 1M and you compete in threadwear 200 classes. But only if you reduce your goal to 400whp and drive in a temperate climate. You will still get oil starvation and some over heating, but at least the internals will last longer.

The last 100whp wont give you much in terms of lap time. My car is around 2s off the best +500hp 1Ms and M2Cs around here. Weight can be more important than power. The fastest 2.0t caymans with upgraded turbos are slightly quicker than all of us.
 
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CAA

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I completly agree with what rac has said. There is plenty of optimisation to chase before the expense of kit and turbo swaps. A twin scroll setup may gain you a possible 500-600rpm with the same turbo. Plenty of articles and data around on twin scroll vs single scroll. The ADE is a good, free flowing manifold. If you must change something like your turbo, a water cooled Gen 2 3076 or 3576, G30-900 or G35-900 may assist.

ADE manifold it's not divided. I think that putting a twinscroll turbo on a undivided manifold is pretty useless.
 

CAA

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N54 + 500whp + RON98 + track driving is just a big no no unless its a massive turbo. If its a 1M and you compete in thread wear 200 classes I can sort of support the setup you are proposing, but only if you reduce your goal to 400whp and enjoy a temperate climate. You will still get oil starvation and some over heating, but at least the internals will last longer.

The last 100whp wont give you much in terms of lap time. My car is around 2s off the best +500hp 1Ms and M2Cs around here. Weight can be more important than power. The fastest 2.0t caymans with upgraded turbos are slightly quicker than all of us.

I have installed supporting cooling mods as said on previous posts, but yes, probably won't be enough. In this case, would be simply as install one or two meth nozzles to cool down IATs.

Regarding for whp goals, I'm agree, that additional 100whp could be problematic to handle and don't give much better lap times, it's not a closed objective to reach 500whp, if it's so much difficult to handle it, I could lower a bit to make the car more handle friendly. Actually, with a ST 6266 I feel the car very handle when is in its powerband, undoubtedly more than stock turbos at the same boost, the problem as stated, is very laggy, and exiting some low speed turns is a pain, so a turbo setup in the middle point of stock turbo snd my current setup I think would be the ideal choice.
 
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Asbjorn

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I run WI with a 200cc nozzle, and it doesn't seem to cool much. A few degrees at most. Having an FMIC with a large frontal area works the best and makes a much larger difference in my experience. What you do not want is a deep FMIC with a small frontal area such as the VRSF 7in. Of course running a large and laggy turbo helps as well.

Anyhow, in terms of laptimes, additional power really only helps above 60mph on the straights. Additional power doesnt help through corners, at low speed or during braking where the biggest time gains and losses happen on a track. Driving skills, tires and weight are so much more important than power. The ROI on a turbo swap and retune is much worse than, say, putting on better tires. But then again, you don't really want to put on better tires when running the N54 on track due to the oil starvation and loss of oil pressure issues.
 
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CAA

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I run WI with a 200cc nozzle, and it doesn't seem to cool much. A few degrees at most. Having an FMIC with a large frontal area works the best and makes a much larger difference in my experience. What you do not want is a deep FMIC with a small frontal area such as the VRSF 7in. Of course running a large and laggy turbo helps as well.

Anyhow, in terms of laptimes, additional power really only helps above 60mph on the straights. Additional power doesnt help through corners, at low speed or during braking where the biggest time gains and losses happen on a track. Driving skills, tires and weight are so much more important than power. The ROI on a turbo swap and retune is much worse than, say, putting on better tires. But then again, you don't really want to put on better tires when running the N54 on track due to the oil starvation and loss of oil pressure issues.
Thanks for your input.
Regarding the oil starvation issue, do you have it even with a pan baffle?
 

Asbjorn

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Thanks for your input.
Regarding the oil starvation issue, do you have it even with a pan baffle?
Yes its still there. Tried two revisions of baffling with oil being pumped by an electric pump from the front of the pan into the inside of the baffle. Theoretically, without a pump, the baffle would mostly help during acceleration. However, I have never seen oil pressure drop under acceleration. It is braking and left hand corners that are the issues.