stock weight on rims: approx. 20lbs w/o tires.

I'm getting the 19in DPK's. They are 26.5lbs. Not to mention, the tires are going to be way heavier as well -- as they are 245/35/19.

Just to get an idea, how much power loss am i anticipating? Anything noticeable? I have to get rims (motegi DPK's are what i'm getting) b/c of the body kit i ordered.
Am i going to feel a noticeable loss in power -- car going to feel sluggish??

Anyone who has 19x8 or somethign similar... what are the cons of getting such bigger rims?

 

With that much difference you will definitely feel the difference. Look at Brillo's vbGarage, he has the stock wheel on a scale and it weighed 22.5 lbs I believe. I called MNAO and they said the stock 18 inch rim weighs 22 lbs. So with your setup you will be 4lbs per corner heavier just from rims. Add on tires and I imagine you will be somewhere near 5-7lbs heavier per corner than stock. Remember, this car is lacking in torque, so any added unsprung weight will be definitely noticable. Again though, this is all about your tastes, do you want more "show" or "go". You can have both, but it will cost you (aren't Volks like $500 a wheel or something?). If you want more go and aren't rich, your options are limited. I would look at Enkei RPM2 and RPF-01. The latter is around 17lbs per wheel.

I went with the Enkei RPM2 in 18x8, 19.4lbs per rim. My tires are Falken GR Beta FK-451 245/40/18 weighing in at 25.5 lbs per tire. So my entire setup is around 45lbs per corner, about 2 lbs ligher than stock.

Do a search on the forum for "unsprung weight" and take a read. It is definitely enlightening.

 

Wow, RPIRX-8, looks good. I was thinking about the RPM2 for my 8 (Winning Blue, baby!), but although it looks good, I think I can see now it's not the look I want.

--Massive

 

Thanks Massive. I'm glad you got to see a blue 8 with these rims on it before you spent the money. I wasn't crazy about the idea at first, I've historically been a thin five spoke wheel guy, but this changed my mind. Just make sure whatever you do, make weight a factor. The car becomes much less fun when weighed down by heavy rims.

What other rims are on your list?

 

there are any number of different factors to take into consideration when trying to answer this question.

first, what is the overall size difference (overall diameter) between the stock wheel/tire combo vs. the new 19" wheel tire combo.

just like in gearing, a larger overall diameter will require more power to accelerate at the same rate.

second is not just weight difference between the two packages, but how the weight is distributed. the further out that weight is on the wheel, the more power needed to accelerate that wheel. use this little fun experiment. sit in a nice office chair, one that can swivel around completely. now, fold your arms and legs up so that you have as much mass near the center of rotation as possible (cross your knees and hold everything in as tight as possible), then have a friend spin you around at a good clip. then extend your arms and legs out away from you and the center of rotation, you should slow down considerably. then bring em back in, you should speed up again. just a fact of physics. figure skaters use this all the time in their routines, when you see a skater spin really fast, notice that their arms and legs are as close to their center as possible, then when the let their arms move out, they slow down dramatically.

 

if you want to keep the performance you have then DONT do it. It will feel like lead weights at the corners and you will definatly notice a slower acceleration.

 

well... i'm going to have a lighter flywheel, pressureplates, clutch... so i'm assuming that'll offset the difference. These are temporary.
I GOT a GREAT DEAL ON THEM!! paying $1200 for Motegi DPK's with tires (approx 70% thread left) shipped! I think that's a great deal.

As for the cornering diff or Accel diff -- how will handling suffer in that the tires are wider and provide more grip (same goes for accel).?

I mean, handling won't suffer (might just feel slihgtly sluggish b/c they are around 10lbs heavier)... will it?

Finally -- how much diff will 10lbs per wheel make???

 

The only thing that is going to help you offset this is a turbo kit. Flywheel, pressureplate, clutch will not help offset the massive increase in unsprung weight you are adding. You car will not be the same car afterwards. I just think you will be very unhappy with the performance degredation.

Your cornering will suffer because the shocks and springs will have to support 10 more lbs per corner. You acceleration will suffer for the same reason. The suspension was designed to deal with a wheel/tire combo that weighs approx 47.5lbs. Remember, your shocks/springs are what keep the wheel in contact with the road over imperfections and in cornering. Now you add 10 more lbs to each wheel. The shocks will not be able handle that weight difference.

Also consider the reduction in braking performance. Now when you apply the brakes each caliper will have to stop 10 more lbs of rotational weight.

I just think all around you will not find the looks of the wheel offset the degredation in performance.

 

Nope, a lighter flywheel will NOT offset the difference that heavier wheels/tires make.

There's a TON of information about this in the sticky thread, Effect of wheel/tire weight on performance . Do yourself a big favour, and READ all of that thread.

Heavy wheels and tires don't just affect acceleration, they affect braking (harder to stop), and make the ride rougher and bouncier. They also affect handling - on billiard table smooth pavement, you can get better handling from a larger diameter wheel with GOOD lower profile tires. Cheap tires will give worse handling, of course. However, if the pavement is rough or rippled at all, then the heavier wheel/tire combination is harder for the shocks to control, and you end up with less traction overall because the shocks aren't able to keep the heavy wheel/tire in contact with the pavement as much across rough pavement - the tires/wheels will be bouncing more than lighter units would.

It's fine if you want 19s for appearance, and are aware of the trade-offs in performance you are making to get that appearance. Too many people pretend that there aren't trade-offs, but the downsides are significant. Just make an informed decision!

Speaking of which - if you're thinking of going with a staggered setup (wider wheels and tires in the back), be aware that those will also degrade handling, specifically balance. They will make the car understeer significantly more than stock. Here's another good stickied thread to read: So you think staggered wheels/tires are a great idea?

Regards,
Gordon

 

thanks gordon and rpirx...

As for suspension, i have the mazdaspeed shocks/struts (tokico blues) and the mazdaspeed performance springs. Are they also designed for the wheel/tire combo of approx 47.5lbs?

within the next year, i plan to get the nismo wheels (5spoke w/ polished lip.. or volks). So these rims (heavy rims) are temporary (for the kit i'm getting soon).

 

Stock
23 lbs wheel
31 lbs tires

54lbs

19"
26 lbs
26lbs range 24 to 27lbs

52lbs

The speedo will be off, gas milage on highway will be better but really suck in town.
You will loose 3 tenths to 6 tenths in quarter mile.
Handling will be slugish.
The tires will be a bitch to install. You will pay high bucks.
Wheels will get damaged over long run as eventually a installer will damage them.
Tires more expensive.
Only high performance low to moderate wearing tires available.
A new Volkswagon bug will beat you in the straights.
A stock Neon non Turbo will smoke your ****.

Any more reasons?

 

Not necessarily true. Go to : www.edgeracing.com to see the weight of the tires. Insome cases the 19" tires actually weight less than the stock 18" tires that we have (which according to Tire Rack weigh 27 lbs.). And the stock wheel weight is 22-23 lbs., not 20 lbs.

 

the tires being put on are 245/35/19. They are the Nitto 555's i believe?
also, how will the speedometer be off??

 

There is a tire size calculator on www.1010tires.com. From there:

Speedo will be off .5mph too fast at 60mph
New wheels will spin 6.8 more revolutions per mile
Your sidewall height will decrease by 15mm

Go take a look, its good information. A 15mm decrease in sidewall height will def make you more succeptable to a bent rim.

 

Crap tires. A favourite of the sport compact crowd because they're cheap, but they are definitely NOT a real performance tire.

Therefore, your car with those wheels and tires WILL be slower, ride worse, and handle worse. But hey, it will look "cool"! (at least to those who don't know much about wheels and tires... those who do will be rolling their eyes! )

Regards,
Gordon

 

how about that is your thoughts

nitto tires are not cheap or bad

 

No, it's pretty easy to measure the performance of tires and compare them. In ANY performance tire test where they've been included, the Nitto tires finish at the bottom of the pack.

Regards,
Gordon

 

I see
I have never seen those tests

but at 170 a tire they are not cheap IMO

 

Add $100 a tire and you are up to the S-O3, add $130 a tire and you are buying PS2s. $170 for a 19" performance tire in that size is cheap.

 

i've heard nitto tires are decent. It's not like i'm gonna be autox'ing anytime soon... these are just show - summer tires i guess.

MikeB, still working on payment. It'll come soon.

Also, the only performance i need from the tires is ... from speeds 60-100ish anyway. Also...
as for braking, will the braking be NOTICEABLY lacking?

James.

 

http://www.miata.net
http://www.sccaforums.com
http://www.corner-carvers.com

Search for nitto on those forums. The tires are in the medicore range in street performance, especially considering the price. (They make good r comps though, they use the RA-1 compound) You'd be better off with checking out the new Hankook's Z212's.

http://www.hankooktireusa.com/pdf/uploads/Z212.pdf

Not only are they cheaper...but they match the RT-215 azenis's in terms of dry grip. The SCCA guys love them.

 

The Toyo RA-1 isn't a great R comp if you're after maxium dry grip/fastest autox times. It is a very good r comp if you want better than street tire grip, durability and longevity, though.

The Hankook Z212 (AKA R-S2) has been getting raves from the ST guys autocrossing them...and may be better than the new Azenis ST-615 (which itself seems to be better than the old RT-215). Thinking of getting a set myself as streets and to function as poor man rain tires. :o

 

Yeah, there's lots of 5-spoke wheels out there that are good, but it's just not that much of a change from the stock wheels. I'd love a set of SSR Comps, since they're 16lbs each--that's down 7lb per corner! Of course, my wallet isn't that thick right now... The Enkei RPF1 look good, especially considering the relatively low price and 18lb weight. Enkei RS+M is nice because of the thin spokes--can't find a price on them, though.

I just can't see getting wheels for this car that don't offer an advantage over the stock wheels other than looks.

--Massive

 

The Kosei K1 TS are less then 16lb if you want 17" and only cost around $240 a wheel. They are my dedicated auto-x wheels. I also appreciate the $ I save on tires every season.