[lockem]

I started this in a new thread to avoid highjacking a paid vendor thread.

Speaking from personal experience modding cars, including full exhaust systems, there's a point where cost per amount of weight saved doesn't return enough value to worry about. If the stock system only weighs approximately 38 lbs, there isn't enough potential weight that can be saved, to be worth the concern. Even if you could cut that in half and save 19 lbs, that's not enough to even feel the difference in the performance of the car. The cost of titanium pipes in my opinion, wouldn't be worth it in this particular case.

I've learned that when it comes to saving weight on a car, not all weight is equal in what it can do for performance. The type of weight you remove, and where you remove it has more of an impact than anything else. You can easily spend thousands on carbon fiber body parts, and maybe save 40-50 lbs, which will make essentially no difference in performance that you can feel. As far as quarter-mile performance, you have to remove 250 lbs of static weight from a car just to gain 1/2 a second at the end of a quarter mile. It's not easy to remove that much weight without gutting the car, and it's not cheap. Not worth it in my opinion; I couldn't tell the difference in 1/2 second anyways.

The best kind of weight to remove, is unsprung rotating weight. That's found in the wheels, brakes, engine flywheel, clutch and driveshaft. Saving 19 lbs in the exhaust system you wouldn't even be able to tell. Saving 19 lbs in unsprung rotating weight you would notice immediately; it makes that much of a difference. Unless you're going for an all-out race build where every pound matters, for a street build, it makes better financial sense to spend your mod money wisely on those areas where you can actually feel the result.

Alfa already gave us a carbon fiber driveshaft, so that's done. Lighter wheels will make a huge difference in performance. Lighter brake rotors just add to that difference. Flywheel and clutch are a different matter, and while they do make a difference, there's more work involved in changing them out, and it can make the stop-and-go performance not as smooth as stock. Where a lighter flywheel and clutch make a difference, is once you're rolling. The throttle response and engine braking are noticeably improved, which you really appreciate in the corners and out on a road course or autocross. Around town... it's more touchy to get the car going, but for those who are more hardcore and want that kind of snap-quick response, there's nothing like it.

For this particular car, my first area of improvement would be lighter wheels. I think that would give you the biggest bang for your buck as far as something where you can feel a difference. Of course you can do chip mods and such, but those void your warranty. Keeping in mind Alfa's past reputation, I'm not in favor of voiding my warranty.

So Joe... as for this cat-back system, I'm curious... why did you choose a 3 inch pipe? Did you try a 2.5 inch pipe system? Was there a performance advantage, or did it just sound better?

Shaving weight is certainly expensive and I agree that the best weight to shave is from the wheels. Weight shaved from wheels improves handling and yields a disproportionate improvement in acceleration. However, for Giulia 2.0T shaving 250 lbs is equivalent to adding about 20HP to the engine while also improving stop-and-go fuel efficiency. It is only possible to improve engine performance so much before major drive line changes are needed and/or the vehicle is no longer street legal (won't smog).

From what I see the upper limit to weight shaving from Giulia 2.0T is around 150lbs without seriously cutting into functionality and getting to that goal involves a lot of money, parts that currently don't exist, and some changes in functionality. Everything is a tradeoff...

(most weights and prices estimated)
CF wheels save 56 pounds at a cost of $12,000 ($214/lb)
Lightweight rotors save 16 pounds at a cost of $1500 ($93/lb-numbers from similar BMW parts)
Titanium lug set saves 2 pounds at a cost of $350 ($175/lb)
OEM CF hood saves 6.4 pounds at a cost of $6000+ ($940/lb; way too much--this would be much less $$ if it were an order able option)
Disable start-stop and install a lighter battery saves 15 pounds at a cost of $200 ($13/lb)
Aluminum battery cables saves 5lbs at a cost of $200 ($40/lb, assumes stock cables are copper and ignores installation labor cost)
Titanium suspension bolts saves 20 lbs at a cost of $2000 ($100/lb, totally made up numbers, some of this is unsprung)
Titanium springs save 20 lbs at a cost of $4000 ($200/lb, totally made up numbers)
Light weight exhaust save 11lbs at a cost of $1600 ($145/lb, 2.5 inch straight through--this is loud)
Light weight speakers save 5lbs at a cost of $400 ($80/lb, assumes Neo-magnet speakers are available in the right size)
Sparco seats save ?? lbs at a cost of $5600, only available in black, no seat heaters and reduced power controls

P-zero Corsa tires save about 20-30 lbs of unsprung rotational mass, but are very expensive because the tires don't last very long and are not usable in a lot of conditions that many people expect to use their car.

Lightweight forged wheels save about 30 pounds but the cost is still around $200/lb. Forged wheels might be more capable of handling road hazards than CF wheels, I do not know.

Lightweight cast wheels save about 30 pounds at a cost of $800-$1200 which looks a lot better than the CF or forged wheels $/lb, but it is not clear to me if that a cast wheel that weighs the same as a forged wheel is really strong enough. After all, wouldn't this put the forged wheel mfgs out of business if the cast wheels are good enough?

I did not include lightweight flywheel or torque converter as I suspect that most folks (including myself) will not like the rougher idle, increased stress on the transmission, or the need to pull the engine to install it.

 

[BostonDMD]

The best way to save money and gain power is to buy a QV instead......

 

[chaiguy]

@lockem, are you planning on actually racing the car or is this more of a data gathering exercise? Could be cool to see an actual build in progress...

Important to emphasize that this is focused on the Giulia 2.0T

Might also be worth it to see if there are any differences in what's already available in the Giulia QV.

 

[Chipshot]

How difficult would removing the rear seats and seatbelts be? They can always be reinstalled when needed.

 

[MDriver]

The best way to save money and gain power is to buy a QV instead......

^^^^what he said....OP is at roughly over 30k in costs...using his numbers....add that to the cost of a Ti and you get a Quad.
moreover in the words of Sebastian Maniscalco "why would you do that????" to the car....

or is this thread just a "for shitts & giggles" exercise??

 

[wbclassics]

or is this thread just a "for shitts & giggles" exercise??

Surely $hits and giggles.

Guy goes from a 20 year old Mazda Protege to a 2018 Giulia that he talks about dropping another $20k+ into to make it lighter.

Uh huh.

 

[BostonDMD]

Surely $hits and giggles.

Guy goes from a 20 year old Mazda Protege to a 2018 Giulia that he talks about dropping another $20k+ into to make it lighter.

Uh huh.

He needs AWD since he lives in the high Sierras....... that is probably why he is contemplating this project......

 

[lockem]

QV uses too much fuel and is not available with AWD.
The list is for Giulia 2.0T. It is more difficult and more expensive to shave any significant weight off of Giulia QV, even though it starts out heavier than 2.0T. For example, the Tecnico wheels are forged, so to reduce wheel weight CF is the only choice and the weight reduction is 1/2 of what it would be on the 2.0T. Giulia QV already has light weight rotors (or the optional CCM), there is nothing to be saved with aftermarket parts.

For tracking, pulling the rear seat out is a possibility. In most cars the rear bottom cushion is held in with spring clips and snaps out with a few seconds of effort. The rear seat backs might take a bit more effort. I expect that it would be a big deal to remove the rear seatbelts. For racing the interior of the car has to be stripped and a roll bar installed; that saves significant weight but the car is no longer suitable for driving on the road and of no use to me.

If I just bought what I needed I would have gotten a second Subaru Crosstrek or an Impreza. Nobody needs 280HP much less 505HP to drive a sedan on the road--you want it but you don't need it. For me, this is about making the car more fun and enjoyable. This was intended to be an constructive discussion of what works, what doesn't work as well as what is reasonable cost wise. I tossed up a bunch of ideas not all of which may be sound, with a wide range of costs per pound. For example, do any forum members have any experience with CF wheels, other than the now recalled and no longer produced HRE version? Has anybody tried light weight cast wheels? Why are similar weight but much more expensive forged wheels even made if light weight cast wheels are adequate?

My car is on order and isn't due in until December. I am unlikely to do anything other than mount snow tires on it until the spring thaw.

 

[Patrick Hayes]

For a lot of us (myself included) if we were serious about losing weight, we?d start with the driver ?

 

[lockem]

For a lot of us (myself included) if we were serious about losing weight, we?d start with the driver ?

Often said, but not meaningful as I see it because driver weight loss is in addition to shaving weight off the vehicle. Carrying less stuff in the vehicle is another way to improve things that typically costs nothing. Avoiding high weight options (i.e. HK audio and sunroof) when ordering the car puts money in the bank while shaving weight.

In my list in the first post, I should have noted "extra benefits" of some items:

Light weight Neo speakers perform better than cheap ceramic magnet speakers.
CF wheels have a serious "bling factor".
Reduced unsprung weight (wheels, tires, rotors, lugs, suspension parts) improves traction by keeping the tire in better contact with the road.

as well as potential downsides:

CF wheels are more likely to fail catastrophically in a pothole and more likely to be irreparably damaged by "curbing".
Light weight rotors reportedly are more likely to squeal.
Light weight battery will run flat faster than the stock battery.
Aluminum battery cables have to be monitored to corrosion and tightness issues.

 

[aenima396]

drive on a quarter tank of gas, no more. 6lbs per gallon.

 

[neiltyme]

Sounds like you need to wait for the stelvio qv

 

[Eagle7]

drive on a quarter tank of gas, no more. 6lbs per gallon.

This I definitely don't recommend. I just did my first fill-up on the car, and I filled up at 1/4 tank. The car took 12.997 gallons (essentially 13). The tank holds 15.3, so subtracting 13 from 15.3 means there's only 2.3 gallons in the tank at the 1/4 tank mark. Under high-performance driving you'll go through that quick, and also possibly run into fuel starvation issues under hard cornering. Not worth risking damage to your fuel system over a few pounds of gas.

 

[lost1750GTV]

If the point is enjoyment of the vehicle, quit worrying about this stuff and appreciate the car for what it is and can do
There may end up being some cost efficient improvements, but nothing mentioned seems to fall into that category
If you are talking racing, coming from light weight motorcycles where weight actually matters, I humbly suggest that skill matters a whole heck of a lot more anyway,- an observation from a lightweight guy who has seen plenty of fast guys who "compensated" for a seveee weight disadvantage through ability

 

[Eagle7]

After looking through Lockem's list, that's about right when it comes to cost if you're going all-out for a weight-reduction build. However the price is more than just the dollar cost; there's also the dramatic change in the sound, comfort and drivability of the car in normal driving situations. A car modded like that is no longer a comfortable around-town car. It's fast and exciting, but you've made a trade-off in other areas.

I have no desire to do that to my Giulia. I have a 2010 SS Camaro I modded more or less like that, and I can drive it for that kind of fun if I want. The Giulia is such a beautiful, refined and sophisticated car, I don't want to ruin that. The only thing I'm considering doing is lighter wheels. Beyond that I'd have to think about it carefully before making any other changes.

As for why cast or flow-formed wheels are less expensive than forged, forged wheels are usually 2 or 3-piece construction which allows for customization on fitment and finish. Cast or flow-formed are only available in whatever size and spec they're made. Forged have to be hand-fit to the customer's spec, which involves a labor cost for assembly and testing of each individual wheel to make sure they're properly sealed and balanced. Cast or flow-formed are mass-produced. There are no assembly labor costs because the specs can't be changed.

When I gave that figure of 250 lbs to gain 1/2 second, I should have qualified that by saying that was based on a vehicle weighing 3,800 lbs. That info came from Al Oppenheiser the chief development engineer for the Chevrolet Camaro, when they were developing the 6th gen Camaro. I think the Giulia Ti AWD is about the same weight if I'm not mistaken. I'll have to take my Giulia to a scale and get it weighed to see what the actual weight is. I have just about every option on it, so I know it will be heavier than the factory stated weight.

 

[lockem]

After looking through Lockem's list, that's about right when it comes to cost if you're going all-out for a weight-reduction build. However the price is more than just the dollar cost; there's also the dramatic change in the sound, comfort and drivability of the car in normal driving situations. A car modded like that is no longer a comfortable around-town car. It's fast and exciting, but you've made a trade-off in other areas.

I have no desire to do that to my Giulia. I have a 2010 SS Camaro I modded more or less like that, and I can drive it for that kind of fun if I want. The Giulia is such a beautiful, refined and sophisticated car, I don't want to ruin that. The only thing I'm considering doing is lighter wheels. Beyond that I'd have to think about it carefully before making any other changes.

As for why cast or flow-formed wheels are less expensive than forged, forged wheels are usually 2 or 3-piece construction which allows for customization on fitment and finish. Cast or flow-formed are only available in whatever size and spec they're made. Forged have to be hand-fit to the customer's spec, which involves a labor cost for assembly and testing of each individual wheel to make sure they're properly sealed and balanced. Cast or flow-formed are mass-produced. There are no assembly labor costs because the specs can't be changed.

When I gave that figure of 250 lbs to gain 1/2 second, I should have qualified that by saying that was based on a vehicle weighing 3,800 lbs. That info came from Al Oppenheiser the chief development engineer for the Chevrolet Camaro, when they were developing the 6th gen Camaro. I think the Giulia Ti AWD is about the same weight if I'm not mistaken. I'll have to take my Giulia to a scale and get it weighed to see what the actual weight is. I have just about every option on it, so I know it will be heavier than the factory stated weight.

Other than light weight (loud) exhaust and light weight (uncomfortable? reviews are mixed) seats I don't see anything on my list that would compromise ride quality. If I didn't care about ride quality relatively inexpensive mods like carpeting and sound proofing removal as well as light weight glass would have been on the list.

RacerZ reported that his Q2 (IIRC, no sunroof, no HK) weighs in at just over 3500 pounds with a nearly full gas tank. AR claims Q4 adds only 132 pounds, so I guesstimate the weight of the car I have on order to be 3650 pounds.

Light weight wheels essentially count double in performance (some people say 6x, but I don't see a justification for that high valuation), so the high price of CF wheels doesn't look as bad as it initially sounds.

I did not ask why forged wheels cost more than cast, I asked why they are made at all if cast wheels can yield the same weight and strength. I don't think anybody is going to pay 5 times the price for a set of wheels just to be able to say "I've got forged wheels", although I could be wrong...

Forged wheels are made from stronger metal and the forging process further strengthens the metal. If the wheels are multi-piece (HRE) some weight got added for fasteners and such. However, I was comparing 1 piece forged Fuchs/Tecnico wheels to 1 piece cast wheels.

 

[lockem]

If the point is enjoyment of the vehicle, quit worrying about this stuff and appreciate the car for what it is and can do
There may end up being some cost efficient improvements, but nothing mentioned seems to fall into that category
If you are talking racing, coming from light weight motorcycles where weight actually matters, I humbly suggest that skill matters a whole heck of a lot more anyway,- an observation from a lightweight guy who has seen plenty of fast guys who "compensated" for a seveee weight disadvantage through ability

But I am not talking racing and assuming no compromises were taken in the weight reduction other than cost, the driver/rider will be faster in the lighter machine. Not necessarily faster than the other guy, just faster than the same driver in an heavier vehicle. If compromises are taken then all bets are off on the lighter vehicle.

In the case of Giulia an example bad compromise would be to install thin solid disk rotors. These are light, but overheat quickly. When I said light weight rotors I meant aluminum hat type, that have the full thickness of vented metal in the business end. Aluminum hat rotors are also supposedly more resistant to warping that the stock type rotors. The standard rotors on QV are already this type.

I ride a light weight time trial bicycle. It has aerodynamic features that add weight (roughly +3 pounds on an 18 pound bike), in spite of my obsessing about the weight of the machine. It doesn't mean that I ignore the weight of the machine it just means that I recognize the advantages of those heavier parts over lighter parts. I know that for my uses this machine is the most fun for me and the fastest on my routes. Owning such a machine doesn't make me the fastest bicyclist on the road, it just makes me faster than if I was riding a less optimized machine.

 

[lockem]

drive on a quarter tank of gas, no more. 6lbs per gallon.

Only works for short trips.
It's a good plan if trying for 0 to 60 MPH bragging rights, though. At least assuming that the tank pickups work very well under high acceleration.

 

[Eagle7]

Other than light weight (loud) exhaust and light weight (uncomfortable? reviews are mixed) seats I don't see anything on my list that would compromise ride quality. If I didn't care about ride quality relatively inexpensive mods like carpeting and sound proofing removal as well as light weight glass would have been on the list.

RacerZ reported that his Q2 (IIRC, no sunroof, no HK) weighs in at just over 3500 pounds with a nearly full gas tank. AR claims Q4 adds only 132 pounds, so I guesstimate the weight of the car I have on order to be 3650 pounds.

Light weight wheels essentially count double in performance (some people say 6x, but I don't see a justification for that high valuation), so the high price of CF wheels doesn't look as bad as it initially sounds.

I did not ask why forged wheels cost more than cast, I asked why they are made at all if cast wheels can yield the same weight and strength. I don't think anybody is going to pay 5 times the price for a set of wheels just to be able to say "I've got forged wheels", although I could be wrong...

Forged wheels are made from stronger metal and the forging process further strengthens the metal. If the wheels are multi-piece (HRE) some weight got added for fasteners and such. However, I was comparing 1 piece forged Fuchs/Tecnico wheels to 1 piece cast wheels.

With regards to ride quality, I was referring to a significant weight reduction build (which I did on my Camaro) including flywheel and clutch.

I mentioned the cost of cast wheels, in the process of explaining the reason why they differ from forged. With forged, besides strength and a slight reduction in weight (it's often not as much a reduction as you would think), the big reason for buying them besides looks, is typically people want to custom fit the biggest wheel they can without rubbing or clearance issues. A 3-piece wheel can be made to fit perfectly; exact width, exact offset, exact brake clearance. They put the center section on the hub, then start playing with different front and rear rim barrel widths until they get the exact combo that will fit. That of course takes time, which you pay for. Once they have the exact combo, they then have to bolt the 3 pieces together, seal it so it can hold air when a tire is on it, and precision balance it to make sure it's perfectly round and flat. All that has to be done 4 times for a full set of wheels. As you can see, there is a large labor expense which is what drives up the price.

The reason why they might not reduce the weight compared to stock as much as you might think, is usually you're getting a bigger wheel; as big as you can fit, which offsets the weight reduction. The goal is typically to fit as wide a wheel as you can for increased grip and traction, without adding more weight than the stock wheel. The bigger tires weigh more too, but if you can do that and save a few pounds? That's a bonus.

Sometimes you can get lucky, and find a cast or flow-formed wheel that happens to fit what you need. It will be just as strong, and just as light or even lighter than forged, because it doesn't have a couple dozen bolts holding it together. Enkei RPF-1 wheels are just such a wheel, and very popular with the track crowd. You just have to hope it's available in the size, bolt pattern and offset you need. I've already looked, and unfortunately they don't make a wheel that will fit the Giulia.

 

[lockem]

With regards to ride quality, I was referring to a significant weight reduction build (which I did on my Camaro) including flywheel and clutch.

I mentioned the cost of cast wheels, in the process of explaining the reason why they differ from forged. With forged, besides strength and a slight reduction in weight (it's often not as much a reduction as you would think), the big reason for buying them besides looks, is typically people want to custom fit the biggest wheel they can without rubbing or clearance issues. A 3-piece wheel can be made to fit perfectly; exact width, exact offset, exact brake clearance. They put the center section on the hub, then start playing with different front and rear rim barrel widths until they get the exact combo that will fit. That of course takes time, which you pay for. Once they have the exact combo, they then have to bolt the 3 pieces together, seal it so it can hold air when a tire is on it, and precision balance it to make sure it's perfectly round and flat. All that has to be done 4 times for a full set of wheels. As you can see, there is a large labor expense which is what drives up the price.

The reason why they might not reduce the weight compared to stock as much as you might think, is usually you're getting a bigger wheel; as big as you can fit, which offsets the weight reduction. The goal is typically to fit as wide a wheel as you can for increased grip and traction, without adding more weight than the stock wheel. The bigger tires weigh more too, but if you can do that and save a few pounds? That's a bonus.

Sometimes you can get lucky, and find a cast or flow-formed wheel that happens to fit what you need. It will be just as strong, and just as light or even lighter than forged, because it doesn't have a couple dozen bolts holding it together. Enkei RPF-1 wheels are just such a wheel, and very popular with the track crowd. You just have to hope it's available in the size, bolt pattern and offset you need. I've already looked, and unfortunately they don't make a wheel that will fit the Giulia.

I was referencing the "FastWheels" cast Giulia wheels that you posted on the Winter Wheels thread. When comparing wheel technologies for weight, I only compare similar or identical size wheel.

Tire weights are strange, in that many tires with more sidewall but otherwise the same dimension weigh the same or less. Tire weights appear to be poorly correlated with tire dimensions. I do not understand what is going on. Maybe someone in the forums can explain this?

If the engine would behave adequately with a light weight flywheel I think the manufacturer would use it. It is not as-if it costs money to put less material in the flywheel while also straining it less. Giulia already has enough problems with running rough and stalling.

ESE fabricates CF wheels to specification, within some limitations. These are one piece and cut to order. They are not 100% CF, as there is an aluminum hub. CF is not very "bolt friendly" and usually has some kind of glued on metal component for hard points.