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Giulia 2.0L Tech Trivia

13K views 30 replies 12 participants last post by  graleman 
#1 ·
For the gearheads out there, here's some stuff from the Service Manual on the 2.0L models that might be of interest:

1) The turbo intercooler is liquid cooled using a separate low temperature cooling system with an electric pump, dedicated reservoir, and front mounted radiator.

2) There are no conventional intake or exhaust manifolds. The turbo bolts directly to the cylinder head exhaust port and the intercooler bolts directly to the cylinder head intake port. The flow is split/combined internally in the head.

3) A single camshaft operates the 16 valve system. Exhaust valves are operated directly by the cam and have fixed timing. The intake valves use the "MultiAir" system for variable timing. (Google "MultiAir" for full description). There are also two balance shafts.

4) The camshaft is chain driven and the engine is an "interference" design (valves will hit the pistons if the chain breaks during operation).

5) Heat from a lube oil cooler is removed by engine coolant. A dedicated front mounted radiator cools the transmission oil.

6) Driving mode changes include steering force, braking feel, throttle response, turbo boost, shift speed, shift points (rpm), and stability control. Several other functions are affected for models with electronic differential, AWD, electronic shocks, etc.
 
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#4 ·
Are the cam sprockets splined (or keyed) on? Some engines use a bolt-on clamp (this saves space and cost) that can spin and cause a valve train failure.

I wonder how well this multi-air system keeps its adjustment over time? I see that the exhaust valves are reliable bucket and shims, but the cam follower and hydraulic actuator scheme on the intake valve seems a little more questionable. The actuators appear to be a place for leaks to happen and a cam follower will wear faster than bucket-and-shim.

Too bad there is no adjust-ability of the exhaust valve timing, since fiddling with exhaust valve timing can greatly increase engine braking (crack the valve during the compression stroke, or open the valve late during the exhaust stroke). These being how Jakebrake and exhaust brake work, respectively. As the engine gets designed to be more efficient and spin more freely some way to get more engine back pressure (or maybe just bigger brakes?) seems like it will be necessary.

Its good to hear that there is an oil cooler. I presume that this is a water to oil heat exchange from your description (also a good arrangement).

I presume that the transmission has an oil to air heat exchanger. Does anybody have enough experience to know if transmission overheating problems are an issue with this 8speed transmission? Having once had an automatic transmission boil over, spew fluid onto a hot exhaust manifold, and catch the vehicle on fire, I'm a bit leary of automatic transmission heat build up.
 
#6 ·
Are the cam sprockets splined (or keyed) on? Some engines use a bolt-on clamp (this saves space and cost) that can spin and cause a valve train failure.

I wonder how well this multi-air system keeps its adjustment over time? I see that the exhaust valves are reliable bucket and shims, but the cam follower and hydraulic actuator scheme on the intake valve seems a little more questionable. The actuators appear to be a place for leaks to happen and a cam follower will wear faster than bucket-and-shim.

Too bad there is no adjust-ability of the exhaust valve timing, since fiddling with exhaust valve timing can greatly increase engine braking (crack the valve during the compression stroke, or open the valve late during the exhaust stroke). These being how Jakebrake and exhaust brake work, respectively. As the engine gets designed to be more efficient and spin more freely some way to get more engine back pressure (or maybe just bigger brakes?) seems like it will be necessary.

Its good to hear that there is an oil cooler. I presume that this is a water to oil heat exchange from your description (also a good arrangement).

I presume that the transmission has an oil to air heat exchanger. Does anybody have enough experience to know if transmission overheating problems are an issue with this 8 speed transmission? Having once had an automatic transmission boil over, spew fluid onto a hot exhaust manifold, and catch the vehicle on fire, I'm a bit leary of automatic transmission heat build up.
The cam drive sprockets are keyed.

Multiair engines have been in production since 2009 (including Fiat 500's). I haven't heard of any frequent problems.

The transmission cooler is a fairly large air cooled radiator mounted in front of the AC condenser. Based on the illustrations in the Service Manual, it looks to be the same size for all models including the QV. If that's true it's probably more than sufficient for the 2.0L models.
 
#7 ·
For the gearheads out there, here's some stuff from the Service Manual on the 2.0L models that might be of interest:

1) The turbo intercooler is liquid cooled using a separate low temperature cooling system with an electric pump, dedicated reservoir, and front mounted radiator.
.
how does this affect switching the engine off whilst its spinning
is that the whirring noise you can hear after shutdown ? electric cooling ?
 
#8 ·
I didn't find anything in the manual to verify post-shutdown cooling of the turbo. The low temperature cooling system is used to cool the turbo bearing housing in addition to the intercooler so it makes sense that the electric pump would run after engine shutdown to get rid of residual heat.
 
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#14 ·
Is this your first car with stop/start?
 
#11 ·
Balance shafts?
Are these the twin balance shafts rotating in opposite directions at twice the crankshaft's speed as used by Mitsubishi Motors (the current patent owners) on their 4cyl. engines?
 
#12 ·
Based on the chain drive sprocket tooth count in the illustrations, it looks like the right hand balance shaft runs at twice crankshaft rpm. The left balance shaft speed is harder to calculate because it's driven off the back of the oil pump with some gearing. Looking at the gear diameters and assuming it must be a whole number, it's probably a 2X multiplier also.
 
#13 ·
I found this image on one of the other threads.

This is described as the "air intake manifold with integrated charge air cooler and the hot-side turbo duct".
Zoom in and you can read MADE IN CANADA.
 
#18 ·
How would that help with turbo lag?
Maybe Nitrous injection that is only active while the boost is low? Good luck getting it to work properly though...

Don't racing auto-crossers dump and ignite fuel in the exhaust manifold in order to spin up the turbo all of the time? I can't imagine that being road legal though.

I think most of the lag in this system is not caused by the turbo. Most of it is likely to meet smog, fuel economy, and/or safety rules.
 
#23 ·

I guess it's a good think that I decided to not hold out for it then.

On a completely different Giulia tech issue: do you know if the adaptive suspension should function properly even if the unsprung weight has been significantly reduced? By throwing money at the "problem" it should be possible to shave about 20 pounds (9kg) of unsprung weight from each corner of a 2.0T. However, if the adaptive system is tuned to a specific weight, it might do something rude.

CF wheels: save up to 14 pounds each compared to 5 holes, costs a lot but there is a major bling factor.
Rotor and hat setup: save about 4 pounds each (or upgrade to bigger rotors while giving back some of the weight improvement), costs a little less per pound saved as the CF wheels, unless they have to be custom ordered.
Titanium lugs: save .5 pounds per corner, modest cost. Subtle bling factor.
Light weight tires: save anywhere from 1 to 5 pounds per corner, cost varies wildly. FWIW: Pzero Corsas are remarkably light weight, but pretty pricey especially if you factor in the short tread life.

The light weight tires and wheels also are rotating mass so they give a disproportionate improvement in acceleration performance.
 
#24 ·
I'm a big fan of weight reduction in cars, especially unsprung rotating weight. I've been looking and trying to find the weights of the stock wheels, but so far no luck. I'm looking at getting a Giulia Ti Lusso in the next few weeks, which would have the 18" wheels. Does anybody know the weight of them? I'd like to use the stock wheels with snow tires for winter, and get a lighter set for summer.
 
#25 ·
Only a limited number of data points are known to me, each from a different source:

19x8 5 holes: about 25 pounds (a little more than $500 each)
O.Z. 19x9: 23.1 pounds (about $450 each)
Fuchs/Tecnico 19x8.5: 19.25 pounds ($1100 each)
ESE carbon fiber 19x9: 11.5 pounds ($3000 each)

Giulia OEM 18x8 (model?): 26.6 pounds

Reference the following thread:
http://www.giuliaforums.com/forum/2...al-discussion/16617-lightest-ar-wheels-4.html

My plan is to mount 245 40r19 Michelen XIce on the stock 19x8 5 holes for Winter and stare long and hard at my pocket book to determine what I want for summer use. I am pretty sure I will end up with 255 35R19 tires all season tires for summer in any case. Q4 with square setup.
 
#26 ·
Thanks for the info! 26.6 is just about what I'd figured which seems to be typical for OEM wheels. I was thinking Bridgestone Blizzak WS80's in 225/45r18 on the stock wheels for winter. For summer I would like lighter wheels so I'm considering going down to a 17" wheel and going up in sidewall to a 45. Anything below a sidewall ratio of 40 starts to feel like a go-cart to me. This will be a daily driver, so ride comfort is a consideration. I have a tricked out 2010 SS Camaro I set up for track that I can use for... shall we say "brisk motoring". :D

For summer wheels I'm tentatively considering these:

https://www.vividracing.com/catalog...sic-classic-series-wheel-set-p-151337921.html

I'll have to call and find out what the wheel weight would be for a 17x8, but I'm guessing it would be somewhere around 18-19 lbs for a 2-piece forged. The problem I've found, in finding good light-weight wheels is the specs. Hardly anybody it seems makes anything for a 5x110 bolt pattern with a bore of 65.1. The nice thing about the CCW wheel, is the price is for a complete set of 4. It would add $100 to get the size I want, which makes it $1,900 for a set; just have to see what the weight is.

As for tires, I have Michelin PSS on my Camaro which I really like. I'll have to do some more research on tires (haven't done any in a few years) to see what's new, but worst case would be a set of PSS on the 17x8's for summer. If I can take 8-9 lbs of unsprung rotating weight off each corner, that would have the effect of removing 80-90 lbs of static weight off the car. Having done this before on other cars, it's an effect you have to experience to appreciate. Without any other changes, the car feels lighter on its feet and quicker, without doing anything else to it.
 
#27 ·
The lightest weight wheels (noted in the referenced thread) manufactured for Giulia are Fuchs 17x7.5 at about 17 pounds each.
I prefer to stay with 19" wheels, since shorter sidewalls translates to better handling (to a point). Also, it seems that most 17" wheels are narrow and using a wide wheel (rim width should ideally be 0.5 inches more than the tread width of the tire) has been track proven to improve performance in spite of the weight penalty.

And yes, I expect that the car will "feel" better and do everything better with less unsprung weight *unless* it destabilizes the adaptive suspension system.

I can't go with summer compound tires. It was 40F all last night on this summer day and I usually drive at night. If they work for you, go for it.
 
#30 ·
@graleman , I seem to remember that the balance shaft for engines was invented (patented?) by a fellow named Lanchester in the early 1900's. I also seem to remember that Mitsubishi purchased the patent in the 70's and used it extensively on their engines. They also were paid royalties by other manufactures to be able to use the technology on their engines. Notably, Porsche with the 944 and 968 cars. I have no idea if Fiat is paying royalties.
 
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