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2019 Giulia Ti Q2, Performance Pack
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Discussion Starter · #1 · (Edited)
Turbo Specifications:

I purchased this turbo from gottuned.com for 1899 euro plus shipping. There is no core charge.



Gottuned starts out with a brand new OEM turbo and utilizes their CNC to install custom gt2867r sized wheels.

Compressor

Stock Inducer: 42mm
Gottuned Inducer: 50mm

Stock Exducer: 56mm
Gottuned Exducer: 67mm

Turbine

Stock Inducer: 47mm
Gottuned Inducer: 54mm

Stock Exducer: 40mm
Gottuned Exducer: 47mm

Stock:

Automotive tire Motor vehicle Tread Automotive design Bumper


Automotive tire Watch Rim Automotive wheel system Bicycle part



Gottuned:

Reflex camera Cameras & optics Camera accessory Digital camera Camera lens


Camera lens Reflex camera Digital camera Lens Mirrorless interchangeable-lens camera




Gottuned reports they did measuring and modeling and using their precision CNC equipment found this was the largest size wheel set they could fit and offer long term reliability. The turbo has an unlimited mile 12 month warranty.


Installation:

Instructions: turbocharger install08122021.pdf

Installation was not as straightforward as I would have liked on a somewhat top mounted turbo. This turbo bolts directly to the head but the two forward bolts that bolt it to the head cannot be reached without removing the catalytic converter and the water pump discharge pipe. This turns a 2 hour job into an 8 hour job.

Key points:
1. Remove the coolant pipe that runs along the rear of the turbo (between catalytic converter and firewall) and snakes over to the driver side of the engine.
2. Remove Catalytic Converter
3. Unbolt water pump discharge pipe and move it out of the way (i kept soft hoses connected)
4. Disconnect oil and coolant lines from turbo
4. Remove turbo heat shield and turbo

Lessons learned: do not overtorque the coolant or oil lines. Its miserable to have leaks but I overtorqued them by probably only 8ft/lb and snapped the head off. It took about 2 hours and two hardware store runs to get the bolt out.

Replacement parts:
1. Turbo to catalytic converter gasket. This should not be reused. PN: 68315166AA
2. Two bolts (pn: 68332357AA) and two nuts (pn: 68310551AA ) securing the turbocharger to the catalytic converter
3. 4 nuts securing the turbo to the head. PN: 6506619AA
4. two orange water line o-rings to the turbo. PN: 68338389AA
5. and 6. two black (two different sizes) oil line o-rings to the turbo (optional. mine were perfect)
PN: 68374709AA and 68374710AA

Photos:

Motor vehicle Hood Automotive fuel system Automotive tire Automotive design


Motor vehicle Hood Automotive exterior Automotive air manifold Automotive fuel system



Turbo Performance:


The stock gt2056ksz is an excellent turbo for what it is. It is an extremely fast spooling twin scroll turbo. It provides immediate torque delivery. Its limitations, however, are that is relatively small size means it makes peak boost low at 2500rpm and can only hold this peak boost to approximately 3500rpm where the boost begins a steady decline to redline.

When you tune the stock turbo this boost limitation in the upper rpm band is even more obvious.

If you look at the blue boost line in the graph below you see the stock turbo is maxed at around 30psi but only in that 2600rpm to 3500rpm range and then it tapers dramatically to approximately 21 to 22psi by redline.

For scooting in and out of traffic at 2500rpm where 99 percent of drivers use their cars this turbo is perfect.

For Wide Open Throttle acceleration runs, however, the car will never see 2500rpm to 3500rpm. During wide open throttle accelerations runs such as those used in performance driving, 1/4 mile runs, and road course driving the engine will generally stay between 4800rpm and 5900rpm.

Stock Turbo at Max Boost:

Rectangle Slope Font Plot Parallel



The hybrid turbos larger wheels mean approximately 500rpm more of turbo lag. The boost on this turbo will not "spike" down low at 2500rpm and then taper off just when you wanted to go fast. Rather it builds more progressively peaking at 3100rpm and then holding this boost to redline making 26psi or more at redline as opposed to the stock 21 to 22psi.

It should be noted this is not the max boost of the hybrid turbo. The below blue boost line shows only 65 percent wastegate duty however the manufacturer of the turbo cautions any use above 26psi (as would any turbo manufacturer). Ive chosen a road course type setup that favors reliability over one and done 1/4 mile runs so I am keeping boost low.

Hybrid Turbo at 65 percent wastegate duty:


Slope Font Plot Parallel Rectangle



Hybrid Turbo at 70 percent wastegate duty.

Rectangle Slope Font Plot Parallel


Tuning:

I am currently using the JB4 making custom maps for this turbo. This option is working extremely well.

BOOST:

There is no hints of limp modes like some people experience with piggybacks trying to get every last pound of boost out of the stock turbo.

That is because at 26psi this hybrid turbo still has headroom in it. You have extra headroom with this turbo so you do not get any chance of underboost codes or limp modes like you can with the stock turbo trying to get just a half more psi out of it hoping it will make that boost.

WASTEGATE DUTY:

As you can see in the above hybrid turbo log the throttle plate (orange jagged line at the top of graph) closes in spots up top in the rev range. This is normal and also seen in stock non tuned turbo because there is plenty of head room left in the turbo. The throttle plate opens to regulate overboost -- when the turbo starts to make more boost than is requested. We dont see throttle plate closing with the stock turbo graph above that is the stock tuned turbo because the actual boost can barely keep up with requested boost. The turbo is completely maxed out.

FUEL:

The hybrid turbo is able to achieve the stock factory fuel enrichment curve for performance driving. The stock engine management (like most stock engine managements) uses a very lean fuel curve in part throttle driving for outstanding fuel economy and then uses enrichment tables for wide open throttle performance driving in order to protect components. This WOT enrichment is approximately 11:1 AFR on the stock turbo and is identical on the hybrid turbo as you can see in the yellow line in the graphs above.

TIMING:

Timing remains shit on these cars. There is zero evidence of knock retard, however, when pushing this turbo. Timing advance remains the same as stock turbo at around .5 to 2 degrees advance only between 5k and 5900rpm. So far no tuner has developed high timing files (e30 or race gas). At the least the timing is safe using JB4 with zero knock on 93 octane.

INTAKE AIR TEMPERATURES:

We do not want to exceed 65c/149f intake air temps on modern forced induction cars. This helps prevent us from running into safety tables that will automatically reduce timing and boost. This also affords us the best performance.

Currently the stock air to water cooling system is keeping IAT within normal limits in grueling south florida temperatures doing back to back 0-150mph torture testing. In order to improve these temperatures even further we can add an additional large surface area heat exchanger to cool the fluid that goes to the intercooler. This is a cheap, easy, effective, and common practice in improving air to water cooling.


Vehicle Performance:

Vehicle performance will change based on ambient conditions also known as density altitude. In general, these cars will gain 1mph in trap speed or 10hp for every 1000ft in density altitude you can drop them.

In other words, the stock vehicle may make 290hp in 60 degree sea level conditions (0 density altitude). It may make 280hp on a 75 degree day at positive +1000 density altitude. It may make 270hp on a 95 degree day at positive 2000 density altitude. It may make 300hp during a 45 degree day at a negative 1000 density altitude.


This vehicle: 2019 Giulia 2.0l ti with perforamance package and no sunroof.
Stock Cooling (using 98 percent water and 2 percent super coolant in turbo cooling loop)
Stock intake.
Stock Catalytic Converter
Stock Exhaust Center Section
Muffler delete (axleback section)


Trap speeds and acceleration testing confirms the stock light weight Q2 (non sunroof) vehicle generally varies in trap speed from 102mph in positive 1000 density altitude to 104mph in negative 1000 density altitude.

The same car with the stock turbo making maximum boost with a tune ranges in trap speed from 104mph in positive 2000 density altitude to 107mph in negative 1000 density altitude.

The hybrid turbo set to 26psi is trapping 107 to 108mph in positive 1500 density altitude.

Lets normalize this data:

Positive 1500DA:

Stock turbo on stock tune: 101.5mph - ~280hp
Stock turbo on max boost tune: 104.5mph - ~310hp
Hybrid turbo on 26psi boost tune: 107.5mph - ~340hp

Add 15hp to all of these numbers in 0 density altitude.

Subjective Driving Impressions:

At this point I have put 500 miles on this turbo with 100 of them break in miles to shake down leaks and the other 400 of them tuning and torture testing.

Already I have been on a 200 mile rally with the Ferrari club with this turbo pushing it to max boost in 40-130mph driving consistently for 150 of the 200 miles.

I have also completed approximately 100 testing runs consisting of 0-130mph and 0-150mph with part-throttle to full throttle (lift and plant, lift and plant) testing in order to assess the limits of the stock cooling system, the max egts, the fuel system, and to assess for any and all conditions a limp mode could occur from things like boost requests not being met or fuel pressure not able to keep up. There have been zero issues at all through the testing which I was amazed by.

What i've noticed and been most impressed by is the power deliver for performance driving. No longer is there a massive boost spike to 30psi down low at 2500rpm and a taper in power up top. This is really no fun for road course driving or canyon carving when you power out of a turn with just 50% throttle and get a 30psi boost spike that upsets the rear for the car. Now the boost comes in progressively holding to redline. Its a more enjoyable performance driving experience.


Mike
 

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I would say for how easy the install and the price it’s worth using especially with a jb4 and stock cat!! Overall good work. Gaining 3mph isn’t easy. Would be interesting to see what it does with dyno tune and hfc. I think it could hit 110mph. But this set up is virtually undetectable for warranty work. So nice balance
 

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I'd like to comment on 26psi being a turbo limit.

Below is the compressor graph. Pressure ratio is (boost + atmosphere)/atmosphere. Airflow can be guestimated as hp/10.

The island of peak turbo efficiency is at a PR of 2.7 which is 26psi of boost. However, in the range of 35-40 lbs of air, you only lose 1% of the turbo efficiency as high as a PR of 3 (about 30 psi of boost) and you are still very far from the compressor surge line.

I would feel very comfortable up to 30psi in this application


Slope Triangle Rectangle Font Line
 

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2018 Giulia Ti Sport Q4
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I'm not moderating SHIT until I see 30PSI results.
 

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'20 Ti-Sport Carbon Q4 Rosso Comp
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2019 Giulia Ti Q2, Performance Pack
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Discussion Starter · #9 ·
Lol well im usually not shy about breaking shit but since my entire body is still sore from the install and my turbo warranty is good to 26psi those are the results we'll be seeing lol.

But theoretically i agree id feel comfortable pushing 28psi easy.

I spin tvs superchargers to 25k rpm routinely and never had one fail but they take 20 minutes to install too lol.
 

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2018 Giulia Ti Sport Q4
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ahh, so it's not a garrett wty, it's a gottuned wty that limits to 26psi. Gotcha.

PM sent. :p
 

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Lol well im usually not shy about breaking shit but since my entire body is still sore from the install and my turbo warranty is good to 26psi those are the results we'll be seeing lol.

But theoretically i agree id feel comfortable pushing 28psi easy.

I spin tvs superchargers to 25k rpm routinely and never had one fail but they take 20 minutes to install too lol.
One run won’t hurt. Everyone’s doing it. You don’t wanna be cool like the rest of us.
 

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2018 Giulia Ti Sport Q4
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4,215 Posts
One run won’t hurt. Everyone’s doing it. You don’t wanna be cool like the rest of us.
pfft, what a pussy, I run 30 psi everyday.
 

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Turbo Specifications:

I purchased this turbo from gottuned.com for 1899 euro plus shipping. There is no core charge.

Gottuned starts out with a brand new OEM turbo and utilizes their CNC to install custom gt2867r sized wheels.

Compressor

Stock Inducer: 42mm
Gottuned Inducer: 50mm

Stock Exducer: 56mm
Gottuned Exducer: 67mm

Turbine

Stock Inducer: 47mm
Gottuned Inducer: 54mm

Stock Exducer: 40mm
Gottuned Exducer: 47mm

Stock:

View attachment 117066

View attachment 117068


Gottuned:

View attachment 117069

View attachment 117070



Gottuned reports they did measuring and modeling and using their precision CNC equipment found this was the largest size wheel set they could fit and offer long term reliability. The turbo has an unlimited mile 12 month warranty.


Installation:

Instructions: turbocharger install08122021.pdf

Installation was not as straightforward as I would have liked on a somewhat top mounted turbo. This turbo bolts directly to the head but the two forward bolts that bolt it to the head cannot be reached without removing the catalytic converter and the water pump discharge pipe. This turns a 2 hour job into an 8 hour job.

Key points:
1. Remove the coolant pipe that runs along the rear of the turbo (between catalytic converter and firewall) and snakes over to the driver side of the engine.
2. Remove Catalytic Converter
3. Unbolt water pump discharge pipe and move it out of the way (i kept soft hoses connected)
4. Disconnect oil and coolant lines from turbo
4. Remove turbo heat shield and turbo

Lessons learned: do not overtorque the coolant or oil lines. Its miserable to have leaks but I overtorqued them by probably only 8ft/lb and snapped the had off. It took about 2 hours and two hardware store runs to get the bolt out.

Replacement parts:
1. Turbo to catalytic converter gasket. This should not be reused.
2. Two bolts and two nuts securing the turbocharger to the catalytic converter
3. 4 nuts securing the turbo to the head
4. two orange water line o-rings to the turbo
5. and 6. two black (two different sizes) oil line o-rings to the turbo (optional. mine were perfect)

Photos:

View attachment 117063

View attachment 117064


Turbo Performance:


The stock gt2056ksz is an excellent turbo for what it is. It is an extremely fast spooling twin scroll turbo. It provides immediate torque delivery. Its limitations, however, are that is relatively small size means it makes peak boost low at 2500rpm and can only hold this peak boost to approximately 3500rpm where the boost begins a steady decline to redline.

When you tune the stock turbo this boost limitation in the upper rpm band is even more obvious.

If you look at the blue boost line in the graph below you see the stock turbo is maxed at around 30psi but only in that 2600rpm to 3500rpm range and then it tapers dramatically to approximately 21 to 22psi by redline.

For scooting in and out of traffic at 2500rpm where 99 percent of drivers use their cars this turbo is perfect.

For Wide Open Throttle acceleration runs, however, the car will never see 2500rpm to 3500rpm. During wide open throttle accelerations runs such as those used in performance driving, 1/4 mile runs, and road course driving the engine will generally stay between 4800rpm and 5900rpm.

Stock Turbo at Max Boost:

View attachment 117074


The hybrid turbos larger wheels mean approximately 500rpm more of turbo lag. The boost on this turbo will not "spike" down low at 2500rpm and then taper off just when you wanted to go fast. Rather it builds more progressively peaking at 3100rpm and then holding this boost to redline making 26psi or more at redline as opposed to the stock 21 to 22psi.

It should be noted this is not the max boost of the hybrid turbo. The below blue boost line shows only 65 percent wastegate duty however the manufacturer of the turbo cautions any use above 26psi (as would any turbo manufacturer). Ive chosen a road course type setup that favors reliability over one and done 1/4 mile runs so I am keeping boost low.

Hybrid Turbo at 65 percent wastegate duty:


View attachment 117072


Tuning:

I am currently using the JB4 making custom maps for this turbo. This option is working extremely well.

BOOST:

There is no hints of limp modes like some people experience with piggybacks trying to get every last pound of boost out of the stock turbo.

That is because at 26psi this hybrid turbo still has headroom in it. You have extra headroom with this turbo so you do not get any chance of underboost codes or limp modes like you can with the stock turbo trying to get just a half more psi out of it hoping it will make that boost.

WASTEGATE DUTY:

As you can see in the above hybrid turbo log the throttle plate (orange jagged line at the top of graph) closes in spots up top in the rev range. This is normal and also seen in stock non tuned turbo because there is plenty of head room left in the turbo. The throttle plate opens to regulate overboost -- when the turbo starts to make more boost than is requested. We dont see throttle plate closing with the stock turbo graph above that is the stock tuned turbo because the actual boost can barely keep up with requested boost. The turbo is completely maxed out.

FUEL:

The hybrid turbo is able to achieve the stock factory fuel enrichment curve for performance driving. The stock engine management (like most stock engine managements) uses a very lean fuel curve in part throttle driving for outstanding fuel economy and then uses enrichment tables for wide open throttle performance driving in order to protect components. This WOT enrichment is approximately 11:1 AFR on the stock turbo and is identical on the hybrid turbo as you can see in the yellow line in the graphs above.

TIMING:

Timing remains shit on these cars. There is zero evidence of knock retard, however, when pushing this turbo. Timing advance remains the same as stock turbo at around .5 to 2 degrees advance only between 5k and 5900rpm. So far no tuner has developed high timing files (e30 or race gas). At the least the timing is safe using JB4 with zero knock on 93 octane.

INTAKE AIR TEMPERATURES:

We do not want to exceed 65c/149f intake air temps on modern forced induction cars. This helps prevent us from running into safety tables that will automatically reduce timing and boost. This also affords us the best performance.

Currently the stock air to water cooling system is keeping IAT within normal limits in grueling south florida temperatures doing back to back 0-150mph torture testing. In order to improve these temperatures even further we can add an additional large surface area heat exchanger to cool the fluid that goes to the intercooler. This is a cheap, easy, effective, and common practice in improving air to water cooling.


Vehicle Performance:

Vehicle performance will change based on ambient conditions also known as density altitude. In general, these cars will gain 1mph in trap speed or 10hp for every 1000ft in density altitude you can drop them.

In other words, the stock vehicle may make 290hp in 60 degree sea level conditions (0 density altitude). It may make 280hp on a 75 degree day at positive +1000 density altitude. It may make 270hp on a 95 degree day at positive 2000 density altitude. It may make 300hp during a 45 degree day at a negative 1000 density altitude.


This vehicle: 2019 Giulia 2.0l ti with perforamance package and no sunroof.
Stock Cooling (using 98 percent water and 2 percent super coolant in turbo cooling loop)
Stock intake.
Stock Catalytic Converter
Stock Exhaust Center Section
Muffler delete (axleback section)


Trap speeds and acceleration testing confirms the stock light weight Q2 (non sunroof) vehicle generally varies in trap speed from 102mph in positive 1000 density altitude to 104mph in negative 1000 density altitude.

The same car with the stock turbo making maximum boost with a tune ranges in trap speed from 104mph in positive 2000 density altitude to 107mph in negative 1000 density altitude.

The hybrid turbo set to 26psi is trapping 107 to 108mph in positive 1500 density altitude.

Lets normalize this data:

Positive 1500DA:

Stock turbo on stock tune: 101.5mph - ~280hp
Stock turbo on max boost tune: 104.5mph - ~310hp
Hybrid turbo on 26psi boost tune: 107.5mph - ~340hp

Add 15hp to all of these numbers in 0 density altitude.

Subjective Driving Impressions:

At this point I have put 500 miles on this turbo with 100 of them break in miles to shake down leaks and the other 400 of them tuning and torture testing.

Already I have been on a 200 mile rally with the Ferrari club with this turbo pushing it to max boost in 40-130mph driving consistently for 150 of the 200 miles.

I have also completed approximately 100 testing runs consisting of 0-130mph and 0-150mph with part-throttle to full throttle (lift and plant, lift and plant) testing in order to assess the limits of the stock cooling system, the max egts, the fuel system, and to assess for any and all conditions a limp mode could occur from things like boost requests not being met or fuel pressure not able to keep up. There have been zero issues at all through the testing which I was amazed by.

What i've noticed and been most impressed by is the power deliver for performance driving. No longer is there a massive boost spike to 30psi down low at 2500rpm and a taper in power up top. This is really no fun for road course driving or canyon carving when you power out of a turn with just 50% throttle and get a 30psi boost spike that upsets the rear for the car. Now the boost comes in progressively holding to redline. Its a more enjoyable performance driving experience.


Mike
 

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2019 Giulia Ti Q2, Performance Pack
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Discussion Starter · #17 · (Edited)
You bet all. Theyll be plenty of acceleration data forthcoming. Im still monitoring everything to see what can get best times and da is still bad here. Im 3mph down in traps right now due to DA.

As an example i did my stock turbo record breaking 8.46 time 40-100mph in negative 1000DA but in positive 1200 DA it would be 9.5 seconds.

Here's 40-100 from yesterday

Rectangle Font Parallel Screenshot Circle



60-130..


Product Rectangle Font Screenshot Parallel



1/4


Rectangle Azure Font Screenshot Parallel
 

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You bet all. Theyll be plenty of acceleration data forthcoming. Im still monitoring everything to see what can get best times and da is still bad here. Im 3mph down in traps right now due to DA.

As an example i did my stock turbo record breaking 8.46 time 40-100mph in negative 1000DA but in positive 1200 DA it would be 9.5 seconds.

Here's 40-100 from yesterday

View attachment 117097


60-130..


View attachment 117099


1/4


View attachment 117098
More Power-less traction.
Get that 60’ down to 1.9 it’s [email protected] in same DA. In negative will hit [email protected]
60-130 seems a little slow but I can tell you’re babying it for now. Don’t blame you. Let it settle.
 

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2017 Giulia Ti Sport Q4
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710 Posts
After tracking my car last weekend, I really need more power above 80 MPH. This is gonna be ordered for next year after seeing your numbers. Can you put the MOPAR part #s next to the replacement parts list? Also, how is it without the JB4 tune? I ask because for warranty work, we wouldn't have the piggyback installed, so just curious if it drives fine with it at stock values.
 

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Discussion Starter · #20 ·
After tracking my car last weekend, I really need more power above 80 MPH. This is gonna be ordered for next year after seeing your numbers. Can you put the MOPAR part #s next to the replacement parts list? Also, how is it without the JB4 tune? I ask because for warranty work, we wouldn't have the piggyback installed, so just curious if it drives fine with it at stock values.
Ill add them. It drives just fine on stock tune. No stumbling or codes at all
 
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