Jump to content
SAU Community

Wheel Weight

Marshan
 Share

Recommended Posts

Marshan Collaborator

Marshan

Posted
Posted

Looking to get new rims. Does anyone here have any experience with the weight of the wheel?

I'm currently running on stock 17" (no idea how much these weight) and looking to go 19". My mates telling me heavy rims can be felt to decrease performance.

I'm not too sure how it will affect our cars as we kinda have a bit of torque to play with. But looking at some Stance sc-5ive and i'm reading their about 29-31pounds (rim only) for the 19".

Is that too heavy?

Cheers guys.

Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/
Share on other sites
sonicii Veteran

sonicii

Posted
Posted

Spinning the wheels up to speed requires some power, heavier wheels will require more power, not sure how much you will actually feel this, but it is a factor.

The other issue is unsprung weight. heavier wheels add to unsprung weight and create more initeria in the suspension, meaning the suspension won't be able to react to changes in the road surface as quickly. Again, I am not sure how much you will actually feel this..

This is why people like the Rays 19s, as they are quite light.

Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6494967
Share on other sites
Marshan Collaborator

Marshan

Posted
  • Author
Posted

Spinning the wheels up to speed requires some power, heavier wheels will require more power, not sure how much you will actually feel this, but it is a factor.

The other issue is unsprung weight. heavier wheels add to unsprung weight and create more initeria in the suspension, meaning the suspension won't be able to react to changes in the road surface as quickly. Again, I am not sure how much you will actually feel this..

This is why people like the Rays 19s, as they are quite light.

Yeah i wonder if anyone has experienced this. Or whether or not we can feel the difference for a set that's 30 pound.

My mate's also saying that since our car has a bit of torque it won't matter that much. Might be something trivial.

Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6494989
Share on other sites
djr81 Grand Master

djr81

Posted
Posted

Yeah i wonder if anyone has experienced this. Or whether or not we can feel the difference for a set that's 30 pound.

My mate's also saying that since our car has a bit of torque it won't matter that much. Might be something trivial.

As already stated it wont make a bit of difference to your acceleration - it is another 40lbs you are adding to the weight of the car - not a big figure given the thing will weigh over 3000lbs to start with.

What it will do is degrade the cars ride and its handling. The heavier the tyre/rim/brake/suspension arm set (refered to as unsprung weight) the harder the suspension has to work to keep the tyre on the road. So your 30lb wheel (which is thereabouts of 10lbs heavier than a good 17" rim) will have an effect.

Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6495021
Share on other sites
PN-Mad Grand Master

PN-Mad

Posted
Posted

This is why good quality Jap rims are expensive, and knock offs are cheap- actually, just one of many reasons.

My 19" SSR rims are 8.7kgs each(or 19lbs). Even they are not the lightest option- some RAYS rims are even lighter.

Good question. What the other guys have said is correct- your increasing unsprung weight. Remember you have to fit a tyre too, which will be wider and heavier as well, compared to stock.

Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6495062
Share on other sites
Marshan Collaborator

Marshan

Posted
  • Author
Posted (edited)

This is why good quality Jap rims are expensive, and knock offs are cheap- actually, just one of many reasons.

My 19" SSR rims are 8.7kgs each(or 19lbs). Even they are not the lightest option- some RAYS rims are even lighter.

Good question. What the other guys have said is correct- your increasing unsprung weight. Remember you have to fit a tyre too, which will be wider and heavier as well, compared to stock.

I don't track, just daily driving. Not sure if the effect will be very noticeable in respect to ride stiffness or something very trivial....30 pounds are pretty heavy for a wheel imo.

Any idea what the OEM wheel weight are for our cars (i'm guessing 20-21pound for the 17" as mentioned above)?

Edited by Marshan
Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6495075
Share on other sites
PN-Mad Grand Master

PN-Mad

Posted
Posted

Its not about tracking the car and looking for every last 1/10th of performance.

Upgrading wheels and tyres smartly means looking into a myriad of different areas. Unfortunately the "flat cappers" have turned it into looking at one area- "stance".

Things to think about in reality are weight both of wheel and tyre, clearance from suspension structures, Clearance from guards, clearance from brake callipers, Rolling diameter, tyre profile, and width. Plus availability of tyres in chosen size. And lastly Legality.

30lbs is heavy for a wheel, but not the heaviest by far. Imagine all the things the wheel is connected to- suspension, brakes, gearbox, engine, wheel bearings. Changing wheels effects all those parts in different ways. I'm not saying changing wheels will blow your engine up, but pointing out that if you chose a setup with a greatly increased rolling diameter, then expect a decrease in performance. Heavier wheels, your shock absorbers will work harder.

TL/DR;

do your research, going from 17s to 19s will effect the way your car does just about everything.

Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6495113
Share on other sites
sonicii Veteran

sonicii

Posted
Posted

As already stated it wont make a bit of difference to your acceleration - it is another 40lbs you are adding to the weight of the car - not a big figure given the thing will weigh over 3000lbs to start with.

It isn't just the additional weight to the car overall, it is a rotating mass the engine has to spin.

Similar to fitting a lighter flywheel, it is only a tiny difference in overall car weight, but the less mass the engine has to spin, the less power is consumed in doing just that.

But as said, I don't know how much you will notice heavier wheels, as they don't spin anywhere near as fast as a flywheel.

I would also suggest you ensure you select the correct size tyres so the overall wheel diameter is the same.. otherwise you will have all sorts of issues with your speedo..

Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6495399
Share on other sites
t5iv Grand Master

t5iv

Posted
Posted

Form>Function... Just sayin'

Seriously though, heavier wheels will cause more strain on components but it isn't a significant amount. You won't feel much difference and it comes down to what you want. As with anything, you will pay a premium for quality/brand name.

Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6495548
Share on other sites
Marshan Collaborator

Marshan

Posted
  • Author
Posted

Quick question.

19" OEM rays? Which would weight lighter than the 17" i have now. Any decrease in performance?

I know that going from 17 to 19 is a big move and will have significant effect on performance and handling, but not sure how it will turn out if the larger wheels are lighter?

Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6499782
Share on other sites
iamhe77 Grand Master

iamhe77

Posted
Posted

Why would there be a decrease in performance.

Assuming the rolling diameter is very close and the 19's are wider (usually the case with OEM), the main differences will be a greater rubber contact patch due to the wider rim-thus wider tyre (unless you are doing the stretched thing) and a harsher ride due to the lower profile tyres on the 19's.

Also you may notice a small decrease in fuel economy due to the larger contact area with the road (I lost around 0.5km/L).

Reference: I went from OEM 17's on my Stagea to Buddy Club 19's. Both weighed around the same but the BC have 245's on them (9" wide) where as the 17's have 215's on them (7" wide). Car handles much, much better with the new rims... but a lot of that comes down to the tyres.

Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6499990
Share on other sites
sonicii Veteran

sonicii

Posted
Posted

^^ this.. no reason for performance decrese.. just rougher ride, as the lower profile tyres will absorb less..

Although if you run the same tyre pressure, the contact patch size will be the same.. just wider and shorter for wider tyres. Fuel economy may come down to the type of tyre.. maybe also a slight difference in outside diameter??

Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6500105
Share on other sites
iamhe77 Grand Master

iamhe77

Posted
Posted

hmm... I am curious as to how you come to the conclusion that a wider tyre on a larger diameter rim will have the same contact patch as a smaller narrower rim.

I just can't see how the contact patch would be shorter for the tyre on the larger rim. Wider, yes of course... but shorter? Explain?

Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6500125
Share on other sites
sonicii Veteran

sonicii

Posted
Posted

Contact patch size is direclty related to tyre pressure and weight on the tyre, not tyre width. A narrow tyre will have a narrow but longer contact patch, a wider tyre will have a wider but shorter contact patch, assuming the same pressure and weight. The contact patch area remains the same.

There are plently of articles about it.. but a quick search came up with this.

http://autospeed.com/cms/title_Tyres-Grip-and-All-That/A_108915/article.html

Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6500256
Share on other sites
Marshan Collaborator

Marshan

Posted
  • Author
Posted (edited)

Contact patch size is direclty related to tyre pressure and weight on the tyre, not tyre width. A narrow tyre will have a narrow but longer contact patch, a wider tyre will have a wider but shorter contact patch, assuming the same pressure and weight. The contact patch area remains the same.

There are plently of articles about it.. but a quick search came up with this.

http://autospeed.com...15/article.html

I've heard of something like that too. Kinda makes sense.

I remember reading a thread on one of the 350z forums where someone was explaining that the OEM 17" might have a slightly larger contact patch than light weight aftermarket 18" due to the weight and negated grip of the larger wheel. I think you are right on the tyre pressure and weight bit.

Edited by Marshan
Link to comment
https://www.sau.com.au/forums/topic/407387-wheel-weight/#findComment-6500890
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • MBS206
      R32 GTS (RB20DE) Injectors Replacement

      By MBS206 · Posted

      If as it's stalling, the fuel pressure rises, it's saying there's less vacuum in the intake manifold. This is pretty typical of an engine that is slowing down.   While typically is agree it sounds fuel related, it really sounds fuel/air mixture related. Since the whole system has been refurbished, including injectors, pump, etc, it's likely we've altered how well the system is delivering fuel. If someone before you has messed with the IACV because it needed fiddling with as the fuel system was dieing out, we need to readjust it back. Getting things back to factory spec everywhere, is what's going to help the entire system. So if it idles at 400rpm with no IACV, that needs raising. Getting factory air flow back to normal will help us get everything back in spec, and likely help chase down any other issues. Back on IACV, if the base idle (no IACV plugged in) is too far out, it's a lot harder for the ECU to control idle. The IACV duty cycle causes non linear variations in reality. When I've tuned the idle valves in the past, you need to keep it in a relatively narrow window on aftermarket ecus to stop them doing wild dances. It also means if your base idle is too low, the valve needs to open too much, and then the smallest % change ends up being a huge variation.
    • Haggerty
      RB25DE NEO with Haltech ECU

      By Haggerty · Posted

      I guess one thing that might be wrong is the manifold pressure.  It is a constant -5.9 and never moves even under 100% throttle and load.  I would expect it to atleast go to 0 correct?  It's doing this with the OEM MAP as well as the ECU vacuum sensor. When trying to tune the base map under load the crosshairs only climb vertically with RPM, but always in the -5.9 column.
    • CF.Panda
      R34 25GT Engine Light 21

      By CF.Panda · Posted

      AHHHH gotchaa, I'll do that once I am home again. I tried doing the harness with the multimeter but it seems the car needed a jump, there was no power when it was in the "ON" position. Not sure if I should use car battery jump starter or if its because the stuff that has been disconnect the car just does send power.
    • Haggerty
      RB25DE NEO with Haltech ECU

      By Haggerty · Posted

      As far as I can tell I have everything properly set in the Haltech software for engine size, injector data, all sensors seem to be reporting proper numbers.  If I change any injector details it doesnt run right.    Changing the base map is having the biggest change in response, im not sure how people are saying it doesnt really matter.  I'm guessing under normal conditions the ECU is able to self adjust and keep everything smooth.   Right now my best performance is happening by lowering the base map just enough to where the ECU us doing short term cut of about 45% to reach the target Lambda of 14.7.  That way when I start putting load on it still has high enough fuel map to not be so lean.  After 2500 rpm I raised the base map to what would be really rich at no load, but still helps with the lean spots on load.  I figure I don't have much reason to be above 2500rpm with no load.  When watching other videos it seems their target is reached much faster than mine.  Mine takes forever to adjust and reach the target. My next few days will be spent making sure timing is good, it was running fine before doing the ECU and DBW swap, but want to verify.  I'll also probably swap in the new injectors I bought as well as a walbro 255 pump.  
    • AnimalGarage
      spot the stagea

      By AnimalGarage · Posted

      It would be different if the sealant hadn't started to peel up with gaps in the glue about ~6cm and bigger in some areas. I would much prefer not having to do the work take them off the car . However, the filler the owner put in the roof rack mount cavities has shrunk and begun to crack on the rail delete panels. I cant trust that to hold off moisture ingress especially where I live. Not only that but I have faded paint on as well as on either side of these panels, so they would need to come off to give the roofline a proper respray. My goal is to get in there and put a healthy amount of epoxy instead of panel filler/bog and potentially skin with carbon fiber. I have 2 spare rolls from an old motorcycle fairing project from a few years back and I think it'd be a nice touch on a black stag.  I've seen some threads where people replace their roof rack delete with a welded in sheet metal part. But has anyone re-worked the roof rails themselves? It seems like there is a lot of volume there to add in some threads and maybe a keyway for a quick(er) release roof rack system. Not afraid to mill something out if I have to. It would be cool to have a cross bar only setup. That way I can keep the sleek roofline that would accept a couple bolts to gain back that extra utility  3D print some snazzy covers to hide the threaded section to be thorough and keep things covered when not using the rack. 
×
×
  • Create New...