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Discussion Starter · #1 ·
I am stumbling around the interwebz trying to figure out what I have under the hood of my 2017 Guilia Ti. It is not easy to find details. So far I have discovered that its an inline 4 with twin-scroll turbo. 4 valves per cyl., water-cooled intercooler, direct injection. I am still looking for compression ratio, max boost in psi, and factory dyno charts. I come from a Subaru background, so I am curious what the upgrade path will be. 280hp from a 2.0L is not horrible, but with direct injection there may be some more hp to extract without too much danger. Liquid cooled charge air coolers are rather silly since you are using 200 degreee water to "cool" 140-300 deg charge air. Air cooled intercoolers provide a increased level of charge air cooling. It revs somewhat low, has plenty of low end torque, and sounds like the VW Jetta I recently rented.
Here is what AR lists:
ENGINE: ALL-ALUMINUM 2.0-LITER TURBOCHARGED 4-CYLINDER 280HP
Availability Standard on Giulia and Giulia Ti
Type and Description Inline-four, direct injection, turbo
Displacement 121.7 cu. in. (1,993 cc)
Bore x Stroke 3.31 x 3.54 (84.0 x 89.9)
Valve System MultiAir2, SOHC, four valves per cylinder with silent chain driven
timing drive
Hollow assembled exhaust camshaft with end pivot roller finger
followers and hydraulic lash adjusters
Turbocharger Direct mount twin-scroll turbocharger with electric wastegate
actuation. Intake manifold with liquid cooled charge air cooler
Fuel Injection Gasoline direct-injection with injector centrally located in the
combustion chamber
Max injection pressure 2,900 psi
Construction Cylinder head: permanent mold air quenched cast aluminum alloy
with integrated exhaust manifold
Crankcase: precision and cast aluminum alloy with casted steel liners
Crankshaft: super-finished forged nitride steel with journals offset
from cylinder bore centerline
Piston: forged aluminum cooled with pressure actuated oil jets
Power (SAE net) 280 hp (209 kW) @ 5,200 rpm (140 hp/liter)
Torque (SAE net) 306 lb.-ft. (415 N•m) @ 2,000 - 4,800 rpm
Redline on the Instrument Cluster 5,500 rpm
Max. Engine Speed 6,200 rpm
Fuel Requirement Premium unleaded, 91 octane (R+M)/2

detail please if you have them
 

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Engine is listed elsewhere at 1995 cc.

306 lb.-ft. is listed at 2000 RPM

Compression for the 2.0T is reported at 10.0:1
 

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2018 Q4 with Fiamenghi Ti exhaust, Race Mod, and Tecnico wheels.
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Turbo boost is not set to a constant limit, which is probably why you cannot find a value. The ECU apparently limits the total air that gets forced into the engine so that the boost pressure increases with altitude. At sea level the boost is rumored to be limited to about 25psig. It is not clear what the limit is at altitude, but probably at least 30psi.

I thought only the 2.9L V6 had the liquid intercooler. In any case, there is no reason for that liquid to be 200F, since it is a separate circuit from the engine coolant. A liquid intercooler has the advantage of high thermal mass (better response to sudden throttle increases) and potentially reduced pressure loss in the intake.

The octane requirement is 87 (R+M)/2 (i.e. regular), but the recommended fuel is 91. Presumably the engine cannot produce full power on 87 octane fuel.
 

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Another interesting thing about the 2.0T is that it does not have conventional intake or exhaust manifolds. The turbo is bolted directly to the exhaust connection on the cylinder head and the intercooler is bolted directly to the single intake connection. Flows to the individual cylinders is split/combined inside the head. I'm guessing that the advantages are reduced turbo lag and quicker warm up for emission control.
 

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Discussion Starter · #7 ·
Turbo boost is not set to a constant limit, which is probably why you cannot find a value. The ECU apparently limits the total air that gets forced into the engine so that the boost pressure increases with altitude. At sea level the boost is rumored to be limited to about 25psig. It is not clear what the limit is at altitude, but probably at least 30psi.

I thought only the 2.9L V6 had the liquid intercooler. In any case, there is no reason for that liquid to be 200F, since it is a separate circuit from the engine coolant. A liquid intercooler has the advantage of high thermal mass (better response to sudden throttle increases) and potentially reduced pressure loss in the intake.

The octane requirement is 87 (R+M)/2 (i.e. regular), but the recommended fuel is 91. Presumably the engine cannot produce full power on 87 octane fuel.
interesting. 25psi is a lot of boost. a lot of boost is what pops motors. boom!. longevity could be at risk.
and yes a 10:1 compression ratio pushing 25 psi sounds like a predetonation (ping and knock) extravaganza. trying to do that on 87 octane would require the computer to retard timing ...a lot... as far as i would guess. but i a not sure if direct injection remedies that tendency.
does any european vendor sell an engine reflash upgrade??
 

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Discussion Starter · #8 · (Edited)
Another interesting thing about the 2.0T is that it does not have conventional intake or exhaust manifolds. The turbo is bolted directly to the exhaust connection on the cylinder head and the intercooler is bolted directly to the single intake connection. Flows to the individual cylinders is split/combined inside the head. I'm guessing that the advantages are reduced turbo lag and quicker warm up for emission control.
that sounds awesome, except i really dont understand the description of the intake side. is there like a blend door, similar to an A/C system, or something? what of the BOV, wastegate, wastegate solonoid? I am wondering if an intercooler could be added (air to air), and then a waterspray onto that. lets mod this thing!! cold Boost=power.
 

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2018 Q4 with Fiamenghi Ti exhaust, Race Mod, and Tecnico wheels.
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interesting. 25psi is a lot of boost. a lot of boost is what pops motors. boom!. longevity could be at risk.
and yes a 10:1 compression ratio pushing 25 psi sounds like a predetonation (ping and knock) extravaganza. trying to do that on 87 octane would require the computer to retard timing ...a lot... as far as i would guess. but i a not sure if direct injection remedies that tendency.
does any european vendor sell an engine reflash upgrade??
Modern heavy diesels are running about 40psi of boost. Very high performance engines run closer to 60psi of boost, although they generally will not run on 91 octane gas. What matters is if the engine was designed to take the load and heat corresponding to the power being produced. Too many modders and manufacturers simply slap a turbo on the side of an engine that wasn't designed for it and the "ka-boom" follows on which a condemnation of turbo charging is based.

Direct injection controls pinging. Diesels always have direct injection because they run on pinging and the only way to control fuel ignition is to control the timing of when the fuel is introduced into the combustion chamber. Many modern NA engines run compression ratios similar to diesels and can only do so because of the use of direct injection. Because the ECU controls the boost pressure via a solenoid operated valve, I suspect pinging is controlled by reducing maximum boost pressure. The ECU has other controls, although I do not know how flexible they controls are. Spark timing, valve opening dwell and maybe timing, fuel injection dwell and maybe timing.

One potential issue with the integration of the intake manifold into the cylinder head casting is the difficulty of accessing the intake ports for cleaning them. Many direct injection engines have problems with carbon buildup in the intake ports. The carbon comes from oil in the intake air that mostly comes from the PCV system and the turbo charger. Typically to do this cleaning the intake manifold is removed and the now exposed ports are scraped or bead blasted clean with some compatible media such as ground walnut shells. Reducing the carbon buildup issue might be another reason to let the engine cool down before shutting it down.

I tend to leave engine tuning to the experts, and am eagerly waiting for dyno results from Eurocompulsion. It is not trivial to make a mod and determine if it is safe and effective.
 

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First post

Hi Brian
In discussing the liquid intercooling, you mention intake air temp would be at 200F. This would be the temp of the engine coolant circuit.

Usually, liquid intercooling has a separate radiator shedding heat to its own air flow. When not on boost liquid in this circuit would be at ambient temp.

This is likely the case for the new Giulia setups.

:)
 

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It is true about the exhaust turbo bolting to the manifold (pressure pulse charging) and intercooler design which has it own cooling circuit. If you look under the hood the intercooler has its own coolant expansion tank in addition to the normal coolant tank, which gives you the clue ;)

I am using Shell V power 99 RON fuel and my motor runs sweet. My UK spec 200HP runs about 17psi boost as measured so 25psi on the 280hp sounds right.

Here is the design. No: 8 is the intercooler. The text confirms the above.
 

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Thanks for the layout diagrams.
Liquid coolant can hold and remove a lot of heat relative to air. The equivalent system in air to air would likely be much larger and longer.

Your Giulia must be V. good on your "B" roads.

A few years ago we joined the "Giulietta" crowd for their "Fall Tours".
As the touring day progessed the car we had got wider as the roads got narrower.

:)
 

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It is the best car I have driven by a long mile on the wet, slippery and sometimes bumpy B roads. In the dry its a lot of fun in D-mode driving narrow twisty roads. I have standard suspension, the damping and steering is amazing.
 

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Discussion Starter · #14 ·
roger that

Hi Brian
In discussing the liquid intercooling, you mention intake air temp would be at 200F. This would be the temp of the engine coolant circuit.

Usually, liquid intercooling has a separate radiator shedding heat to its own air flow. When not on boost liquid in this circuit would be at ambient temp.

This is likely the case for the new Giulia setups.

:)
good to know! it makes sense that the charge air liquid is divorced from the engine coolant.
Whats the liquid? antifreeze and water? if so, maybe water wetter could increase the efficiency of heat transfer?
 

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Anyone notice that the Owners Manual (NAFTA) lists acceleration differently for RWD and AWD? It lists '280HP RWD engine' and '280HP AWD engine' making it sound like the engines are different. Both have the same top speed, but AWD is 1/2 a second quicker to 60mph despite being heavier by over 100lbs. Is this all down to traction or is there a different software map for each engine? I could envision reducing torque to prevent excessive wheel spin, for example.
 

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Anyone notice that the Owners Manual (NAFTA) lists acceleration differently for RWD and AWD? It lists '280HP RWD engine' and '280HP AWD engine' making it sound like the engines are different. Both have the same top speed, but AWD is 1/2 a second quicker to 60mph despite being heavier by over 100lbs. Is this all down to traction or is there a different software map for each engine? I could envision reducing torque to prevent excessive wheel spin, for example.
Good observation. Yes this has been discussed. It just highlights the AWD is putting the power down just a smidge better.

Remember even the AWD Giulia is 100% RWD until traction slips at which point it will shuffle up to 50% forward.
 

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2018 Giulia Ti Sport Q4
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Does anyone have the internal engine specs? Rod, piston, and crank specs?
 

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Does anyone have the internal engine specs? Rod, piston, and crank specs?
Crank is forged, nitrided and has superfinished journal surfaces.
Piston is forged and underside of crown is oil cooled from oil squirters in the block.
I can't find any info on the rod itself.

That info is from Alfa from one of the 2017 specification sheets I have on the Giulia.

MacGeek, can you contribute any further info? I'd in particular like to know about the piston ring package (ring material, ring thickness size) and whether the piston ring upper ring groove in the piston is hard anodized and what the piston skirt looks like. I'd love to know the OD and wall thickness of the wrist pin as well.
 
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