New rims/ light weight or aero?
 

I recently got a new car and am thinking about what to do about the rims for winter/summer tires.
The car came with those rims (Skoda Alcatraz), I found a weight of 10.2 kg for them.

https://up.picr.de/39233015wa.jpg

My first intention was to use the Alcatraz rims for the winter tires and get new rims for the summer. Skoda offers the Lepus wheels which were used on the greenline eco model and seem to be optimised aero wise. Weight is about the same at 10.1 kg.

https://up.picr.de/39233016ts.jpg

Alternative would be keeping the summer wheels as is and using after market rims (ATS Streetrallye) for the winter tires. They weigh "only" 8.4 kg but still have a reasonable price.

https://up.picr.de/39233017kr.jpg

I´m not sure how the benefits of the lighter rim would be. I had light Rims on my previous car for about 2 month and couldn´t see a difference in fuel despite changing from winter tires to summer tires. But that observation is only based on 2 tanks each since I moved here so not really representative.

My commute is 18 km each with a bit of city driving and mostly country roads with some elevations and an average speed of about 45 km/h (max. 100 km/h).

https://up.picr.de/39233141ey.jpg

Using aero covers for the lighter rims isn´t an option unfortunately.

What do you recon are there any benefits in getting the lighter rims over the aero rims?

I kinda like the idea of the aero rims with the LRR Summer tires to get good results while highway driving.
BTW this isn´t about saving money, I´m just interested in what the car is capable of with little mods. And I need to get another set of rims anyway.

Sorry for the wait on approving the post. Bumping for you now!

The question is harder to answer than you might imagine. Aero wheels do not perform the same in every application, and weight reductions depend upon your driving conditions for their best benefits. Weight reduction is not as valuable for steady state highway driving, but in those same conditions aero drag reductions are more valuable.

You can add pizza pans, but you can't add lightness.

Unless you are drastically reducing the weight of your wheel and tire setup, you most likely won't notice a difference. More aerodynamic wheels will improve mileage slightly, but it will be hard to see the difference unless you perform testing. On my Civic, it took wheels that were seven pounds lighter (11lb ea. vs. 18lb ea.), narrower tires, and smooth wheel covers just to get ~2 MPG increase. Switching to a low rolling resistance tire would probably be able to do all of that by itself.

:) ...yes but a REAL ecomodder gets the LRR tires AND does all of that! :)

Definitely, but if I'm being completely honest here back when I made that swap I didn't realize how much of an effect tires had on efficiency. I think the tires I used were rated for lower rolling resistance than the ones I had, but either way they definitely weren't LRR.

Every mod does not need to be a blockbuster, it simply needs to work with other mods (and the driver, don't forget the driver) to contribute to overall FE.

Remember War_Wagon? His last post was over a year ago. I like to think he gets email notifications of posts to threads he's subscribed to.

His sig was:
"Don't look for one place to lose 100 pounds, look for 1600 places to lose an ounce." - Tony DeFeo

It applies here.

Congrats! That's a nice one, with already good aerodynamics btw.

To answer your question: light weight or aero, I would say: both!
But it seems that's not an option with the rims you show.

With good LLR tires on the greenline rims you will probably get a good result.

What I did: lightweight & aerodynamic forged Audi rims with a taller tire that has a smaller tread and LLR. That has to be the holy grail to succes ON PAPER. However, I have no practical experience with them yet because I still have to change them. But it was much cheaper than a set of new Skoda rims with standard tire size.

Here you have the whole range of lightweight audi rims that you can find second hand:
https://www.original-felgen.com/gewicht

Thanks everyone.
The rims would be the only weight saving and since I´m thinking about adding a spare tire I probably wouldn´t save anything. Only benefit would the lower rotational mass.
To bad the after market isn´t interested in aero wheels :(

The car came with Dunlop Sport Bluresponse tires (205/55 R16), which seems to be quite good fe wise, so it´s not worth changing. I have to run 16" due to the front brakes, so I can´t go any smaller.

Thanks. Cd is 0.315, my Passat had 0.32 not that much improvement for 15 years age difference.
I got a different lower grill yesterday which is partially closed that should help a tiny bit, will install when it gets a bit cooler.
The greenline spoiler would be nice too, but it´s expensive and technically I´m not allowed to fit it. (TÜV says no :mad:)



I probably spent a few hours on the site to find rims for my previous car:D
Unfortunately neither Audi nor VW seems to have a forged Aero wheel that fits my car.
Audi offers a forged rim with a cap for the A4 that would combine aero and lightness. Unfortunately the dimensions a wrong and they are ugly.

Did a little trip after work today and got the consumption down to 4.3 l/100km at an average speed of 66 km/h (top speed 110 on the highway) :D

Lightweight vs Aero
 

FYI

Thank you for your posting I also have had a struggle or justifications on wheel choices and wheel cover

My first hand insight is as follows

Toyota OEM 15 inch 5x100 lug wheels /rims 19 lbs (8kg)(alum/alloy) from what the forums and others have stated additionally the tire is somewhere around 17lbs coming in at 36 lbs....

In the USA tirerack online purchase has Enkei J10 15 inch wheel 5x100 lug for $127 US dollars these are a Japan owned manufacture in Thailand to my understanding ... these scale in at 14-15lbs so 28lbs making 115-113lbs to the current 144lbs I currently have via 19lbs x 17lbs tire /wheel setting 30lbs reduction if I had the Enkei...

Enkei has more lighter 15 inch wheel Enkei RPF1 4x 100 lug scaling in at 9.5lbs so 26-27 lbs with tire.

Keep in mind that since the wheel is closer to the center than the tire, reducing the weight of the wheel will have less effect than reducing the weight of the tire. On the highway you probably wont notice a difference in weight, there it doesn't really make much of a difference. I've loaded my Insight down with hundreds of pounds of stuff for traveling to college, and it doesn't make any difference in a fuel economy on the highway at all. Hills may be slightly slower, and the car may coast little faster and further down the hill, but the fuel economy remains unchanged. Weight reduction helps around town, aerodynamics helps on the highway. If you can get both, that's great, but that really depends more what kind of driving you do the most.

I don't think weight affects highway driving that much. When I switched to steel wheels and 31s, I added about 16 lbs per corner. I still average 21 mpg with mostly highway driving.

If you have the new Octavia 4, Cd is 0.26. The previous model has 0.31 indeed.

I only remove the lower grill cover on tropical days, ~ 30°C is the turning point for me. It's pretty safe unless you're going to drive around like crazy :D


That's good, especially with a new car that has yet to be run in. :thumbup: I expect even better numbers with that new TDI evo engine.

Regarding tire weight, I asked Michelin and Bridgestone for oficial numbers while searching wheels for my previous car.

Michelin Alpin 4 195/65 r15 7.8 kg 17.2 lbs
Michelin Alpin 6 195/65 r15 8.2 kg 18 lbs

Bridgestone Turanza T005 195/65 r15 7.5 kg 16.5 lbs
Bridgestone Turanza T005 205/60 r15 9.3 kg 20.5 lb

I switched fdom my winter setup steelwheel 6jx15 et45 + Alpin 4 15.9kg 35 lbs total per wheel to Autec Wizard 6.5jx15 et38 + T005 14.3 kg 31.5 lbs total per wheel and didn't notice a difference. But I only drove them for 2 tanks before the engine started doing weird things.

It's an Octavia 3, probably one of the last ones build in 06.2020. I needed it quick so I went for a car that was on it's way to the dealer. So no TDI evo :( but atleast I have proper buttons :D

From what I read so far the O4 has great fuel consumption. Wondering if they'll bother doing a greenline model, for the O3 it was only available pre facelift.

Doesn't everybody use tirerack.com for tire weights?

Before I was on ecomodder I never heard of it. But there are a lot of tires on it that are not delivered across the ocean, and a lot of tires that are available here are not on tirerack.

I believe that. ...silly North Americans... often assuming we are the world. :turtle:

Probably the mild-hybrid version of the 1.0 TSI? It will appear later this year, called 1.0 TSI e-TEC...


It's the new world, no doubt about that :thumbup:

I haven't read anything so far that the mild hybrid versions will get a special greenline treatment.
For the Leon 4 1.0eTsi and 1.5eTsi are already available, but aero wise they are the same as the non hybrid versions.