Things not explained in wheel FAQs...

essogas · 08-18-2003, 02:33 PM

First thing I never read in wheel EAQs is the performance trade off (or gain) when plus sizing your wheels. Every tune shop has told me that 18's are not as good as 17's for the STi because the contact patch is bigger with 18's so turn-in and handling is sacrificed. If this is the case wouldn't logic dictate that 16's would be better than 17's then. Anyway, they all said 18' are for show, not performance.

The next question is what about tire widths? Going from 7.5 to 8.5? What is gained or lost here? I'm thinking of going 7.0 for winter (narrower) but I will need new rims...

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Silver-Bolt · 08-18-2003, 06:51 PM

Your biggest enimies will be weight and rolling resistance. Turn in might actaully improve slightly with a lower profile tire. Less sidewall flex. Not that the stock tires have much flex.

Wombat North · 08-18-2003, 07:21 PM

Some quick info
Nathan from turboxs ran a 12.37sec at 3600 ft and if you use the altitude correction factor he was in the 11's. He used stock WRX rims 16 inch.

I used 16 inch stock rims with 50 series tires at the track days in my old WRX which gave me good acceleration and top end but sucked in the corners.

Below copied from Vivid's web site, hope they don't mind.

Now, it has long been believed that bigger is better. In the case of wheels and tires, this only applies to cosmetics. You see, the added weight of a wider tire actually makes the vehicles engine have to work much harder to accelerate. Likewise, as you go to a larger diameter wheel, the weight of the wheel is moved further from the center, and again is much harder to accelerate. In a recent issue of Sport Compact car, they did some tests on the effects of different wheel diameters on acceleration, and track times. They tested 16, 17 and 18-inch wheels, on the same car. They also tested the effect of adding 200 pounds of dead weight to the interior of the vehicle. The difference in quarter mile times and road-course times, as the wheel size was increased, was fairly close to the effect of adding 200 pounds of weight to the car.

The larger diameter wheels, with tires of the same circumference slowed the car down every time. One other consideration when picking wheels and tires is the contact patch. For all intensive purposes, your car has a static mass (if you have a WRX, it's about 3100 lbs). Given a set tire pressure, no matter the tire size (within reason), you will have a set contact patch area. As you drive your car hard into a corner, the tire will start to roll over onto the sidewall. The contact patch changes shape. If 20% of the tire is no longer touching the road, and you have a large round contact patch, then you loose perhaps 25% to 30% of your rubber on the road. If you chose wider tires, and have a longer narrow contact patch, then the 20% of the tire no longer touching the road may only represent a loss of 10-15% of the contact area. This is why people 'should' run wider tires. Anyways, if you want to upgrade your car with the best possible package, choose a high quality tire. Yokohama, Nitto, BF Goodrich and Toyo make some excellent high performance models. If you currently have any sort of all-season on your car, and you want the biggest possible increase in cornering and braking ability, upgrade those tires. As for wheels, pick something that is cosmetically pleasing, but is light weight. Often you can tell the quality of a wheel by price. The incredibly lightweight Volk Racing TE37's are several hundred dollars a wheel, while your local garage may be able to source out an identically sized wheel for well under a hundred dollars. You typically get what you pay for. Don't let your desire for 'bigger is better' get the better of you. Choose quality over quantity!

ciper · 08-18-2003, 08:37 PM

You shouldnt recreate what has already been covered many times. This same thread has happened in the wheels and tires forum too many times to count.

wewu · 08-18-2003, 10:20 PM

17" = go
18" = show
19" = slow

ciper · 08-18-2003, 11:10 PM

16" = go with moh dough (for mods that will make more of a difference)
17" = go
18" = show
19" = slow

RichQY · 08-18-2003, 11:23 PM

16= doesn't fit

1BlueSTi4Me · 08-19-2003, 01:37 AM

Quote:

Originally posted by RichQY
16= doesn't fit

You stole my line !!!

essogas · 08-19-2003, 10:04 AM

Thanks guys, so it's pretty much true what I've been told. And I did check in the wheels forum and found ZERO.

essogas · 09-15-2003, 09:08 PM

I was wondering if anyone else had anything to say about this? I'm having trouble deciding on 17's or 18's...

z · 09-15-2003, 09:15 PM

Quote:

Originally posted by RichQY
16= doesn't fit

Quote:

Originally posted by 1BlueSTi4Me

You stole my line !!!

Dammit, that's what I was gonna say too, try squeezing 16's over those giant brembos and you'll see why they went to 17'z

ciper · 09-15-2003, 09:32 PM

Those posts just show how much misinformation is on this forum. I did a search and the FIRST THREAD on that search had this posting....

Posted by:
Leonardo
Son of Splinter
Moderator

"Well, the good thing about having them on the island is I can check. I know for a fact the Sub-Zeros don't fit but the SDT's (Prodrive knock offs) fit and those were 16!!!!"

In the same thread

Posted by:
Konrad
Scooby Newbie

"according to motorsport specialities, compomotive TH3 15" wheels will fit. I believe that wheel diameter is not the problem but the relationship between the wheel spokes and the side of the monster Brembo's."

Im not going to search for anymore. I just now know you guys are wrong.

peczenij · 09-15-2003, 09:41 PM

Sorry if I misunderstood...
But, ciper
Scooby Specialist, are you saying there are 15 inchers that will fit over the Brembos?

Red Rocket · 09-15-2003, 10:24 PM

Quote:

Originally posted by essogas
I was wondering if anyone else had anything to say about this? I'm having trouble deciding on 17's or 18's...

Hey,

There is nothing wrong with running a set of 18's if you like.

They will in general weigh a bit more and have more rotational interia, but you can find light ones if you look. For example, toyo t1-s weigh 22 lb in a 225/40-18 and 22.9 in a 245/35-18. Light wheels aren't hard to come by either.

The tire will have a reduced sidewall height, which will make a noticeble difference in road feel - you will have a more precise, direct feel from the wheels. You will also have a better chance od damaging the wheels on rough roads.

I personally run a set of 17x9" front and 17x8.5" rear wheels, with 255/40-17 Toyo RA-1's. Probably the grippyest but still streetable setup you could possubly run. The one thing I don't like about them is the sidewall is a little tall and soft - it's grippy and forgiving, but not super precise.

Kevin

z · 09-15-2003, 11:23 PM

Quote:

Originally posted by ciper
Those posts just show how much misinformation is on this forum. I did a search and the FIRST THREAD on that search had this posting....

Posted by:
Leonardo
Son of Splinter
Moderator

"Well, the good thing about having them on the island is I can check. I know for a fact the Sub-Zeros don't fit but the SDT's (Prodrive knock offs) fit and those were 16!!!!"

In the same thread

Posted by:
Konrad
Scooby Newbie

"according to motorsport specialities, compomotive TH3 15" wheels will fit. I believe that wheel diameter is not the problem but the relationship between the wheel spokes and the side of the monster Brembo's."

Im not going to search for anymore. I just now know you guys are wrong.

Seems there is a lot of misinformation going around here:

I did a search on this forum for "SDTs" -for any date- and the only 2 posts that came up were this one and the one you referred to ??

so school me, what are SDT's, bro?

as for the TH3's, I'm going to check on that...we'll see...

EDIT: i wouldn't put those ugly @$$ wheels on my car, anyway. So looks like 17's ????

z · 09-16-2003, 11:33 AM

Quote:

Originally posted by ciper
Those posts just show how much misinformation is on this forum. I did a search and the FIRST THREAD on that search had this posting....

Posted by:
Leonardo
Son of Splinter
Moderator

"Well, the good thing about having them on the island is I can check. I know for a fact the Sub-Zeros don't fit but the SDT's (Prodrive knock offs) fit and those were 16!!!!"

In the same thread

Posted by:
Konrad
Scooby Newbie

"according to motorsport specialities, compomotive TH3 15" wheels will fit. I believe that wheel diameter is not the problem but the relationship between the wheel spokes and the side of the monster Brembo's."

Im not going to search for anymore. I just now know you guys are wrong.

Hey Ciper,
Thanks for more misinformation.

I just got off the phone with Belinda at USA comp (800-621-8408)

She called UK while I was on hold and they said:

"NO THE 15's WILL NOT CLEAR THE BREMBO's"
The 17's will. 17's, get it? NOT 15's.

OK?

she said I should clear up this "misinformation" floating around on the forum before a bunch of "misinformed" fools start ordering their 15's only to realize THEY DON"T FIT!!!!!

thanks for trying though, sucka

EDIT: still waiting to find out what those SDT's are

SubEd · 09-16-2003, 11:49 AM

15's?!?

gforced · 09-16-2003, 11:57 AM

All you guys have to do is look at your wheels and you will know that nothing less than 17" will fit. I know a lot of people pop off info like they know what they are talking about and their comments are idiotic. Just wait and see what the tuners start using or ask somone that has changed their wheels.

jagcars26 · 09-16-2003, 01:56 PM

Could Leo have meant 15 inch ROTA SDRs?? Just a guess,,,,,im running 17 inch SDRs as a winter setup and i know they fit.

Rudy

z · 09-16-2003, 02:54 PM

Quote:

Originally posted by jagcars26
Could Leo have meant 15 inch ROTA SDRs?? Just a guess,,,,,im running 17 inch SDRs as a winter setup and i know they fit.

Rudy

That was Konrad that said the 15's would fit.

ciper · 09-16-2003, 07:29 PM

Im just trying to show everyone that this has been discussed before and others have posted the information.

More than one thread exists with information about wheels smaller than 17 inch fitting.

If the information is incorrect in the other thread you should post that in responce.

I think I read the calipers on the brembos have an effective diameter just greater than 15 inch, meaning the smallest wheel that would fit is something in 16 inch. Cant find that post again though. Did anyone else see it?

I also remember reading about others that have ordered 16 inch wheels for the STI. What do they know that we dont?

z · 09-16-2003, 08:41 PM

Quote:

Originally posted by ciper
Im just trying to show everyone that this has been discussed before and others have posted the information.

More than one thread exists with information about wheels smaller than 17 inch fitting.

If the information is incorrect in the other thread you should post that in responce.

I think I read the calipers on the brembos have an effective diameter just greater than 15 inch, meaning the smallest wheel that would fit is something in 16 inch. Cant find that post again though. Did anyone else see it?

I also remember reading about others that have ordered 16 inch wheels for the STI. What do they know that we dont?

I don't know, but I wouldn't mind getting a pair of 16's for winter, if anyone happens to know of any 16's that fit. If not, 17's it is. No 18's for winter for me.

[email protected] · 09-17-2003, 08:06 AM

there is no way a 15" or a 16" will clear the Brembo's on an STi

08-18-2003, 02:33 PM	#1
essogas Scooby Specialist Member#: 35703 Join Date: Apr 2003 Location: Toronto, Ontario Vehicle: 2004 WRX STi Blue/British Black 18's	Things not explained in wheel FAQs... First thing I never read in wheel EAQs is the performance trade off (or gain) when plus sizing your wheels. Every tune shop has told me that 18's are not as good as 17's for the STi because the contact patch is bigger with 18's so turn-in and handling is sacrificed. If this is the case wouldn't logic dictate that 16's would be better than 17's then. Anyway, they all said 18' are for show, not performance. The next question is what about tire widths? Going from 7.5 to 8.5? What is gained or lost here? I'm thinking of going 7.0 for winter (narrower) but I will need new rims... * Registered users of the site do not see these ads.

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08-18-2003, 06:51 PM	#2
Silver-Bolt Scooby Specialist Member#: 40189 Join Date: Jul 2003 Location: Portland, Oregon Vehicle: 2004 STi Silver/Silver	Your biggest enimies will be weight and rolling resistance. Turn in might actaully improve slightly with a lower profile tire. Less sidewall flex. Not that the stock tires have much flex.

08-18-2003, 07:21 PM	#3
Wombat North Scooby Specialist Member#: 21267 Join Date: Jul 2002 Location: Eats, roots and then leaves Vehicle: STI, EWG 8cm Green UTEC/ECUtek/WI & SD tune	Some quick info Nathan from turboxs ran a 12.37sec at 3600 ft and if you use the altitude correction factor he was in the 11's. He used stock WRX rims 16 inch. I used 16 inch stock rims with 50 series tires at the track days in my old WRX which gave me good acceleration and top end but sucked in the corners. Below copied from Vivid's web site, hope they don't mind. Now, it has long been believed that bigger is better. In the case of wheels and tires, this only applies to cosmetics. You see, the added weight of a wider tire actually makes the vehicles engine have to work much harder to accelerate. Likewise, as you go to a larger diameter wheel, the weight of the wheel is moved further from the center, and again is much harder to accelerate. In a recent issue of Sport Compact car, they did some tests on the effects of different wheel diameters on acceleration, and track times. They tested 16, 17 and 18-inch wheels, on the same car. They also tested the effect of adding 200 pounds of dead weight to the interior of the vehicle. The difference in quarter mile times and road-course times, as the wheel size was increased, was fairly close to the effect of adding 200 pounds of weight to the car. The larger diameter wheels, with tires of the same circumference slowed the car down every time. One other consideration when picking wheels and tires is the contact patch. For all intensive purposes, your car has a static mass (if you have a WRX, it's about 3100 lbs). Given a set tire pressure, no matter the tire size (within reason), you will have a set contact patch area. As you drive your car hard into a corner, the tire will start to roll over onto the sidewall. The contact patch changes shape. If 20% of the tire is no longer touching the road, and you have a large round contact patch, then you loose perhaps 25% to 30% of your rubber on the road. If you chose wider tires, and have a longer narrow contact patch, then the 20% of the tire no longer touching the road may only represent a loss of 10-15% of the contact area. This is why people 'should' run wider tires. Anyways, if you want to upgrade your car with the best possible package, choose a high quality tire. Yokohama, Nitto, BF Goodrich and Toyo make some excellent high performance models. If you currently have any sort of all-season on your car, and you want the biggest possible increase in cornering and braking ability, upgrade those tires. As for wheels, pick something that is cosmetically pleasing, but is light weight. Often you can tell the quality of a wheel by price. The incredibly lightweight Volk Racing TE37's are several hundred dollars a wheel, while your local garage may be able to source out an identically sized wheel for well under a hundred dollars. You typically get what you pay for. Don't let your desire for 'bigger is better' get the better of you. Choose quality over quantity!

08-18-2003, 08:37 PM	#4
ciper Scooby Guru Member#: 15543 Join Date: Feb 2002 Vehicle: 555 Having a Subaru shop means too many cars	You shouldnt recreate what has already been covered many times. This same thread has happened in the wheels and tires forum too many times to count.

08-18-2003, 10:20 PM	#5
wewu Scooby Newbie Member#: 38767 Join Date: Jun 2003 Location: tri-state area	17" = go 18" = show 19" = slow

08-18-2003, 11:10 PM	#6
ciper Scooby Guru Member#: 15543 Join Date: Feb 2002 Vehicle: 555 Having a Subaru shop means too many cars	16" = go with moh dough (for mods that will make more of a difference) 17" = go 18" = show 19" = slow

08-18-2003, 11:23 PM	#7
RichQY Scooby Specialist Member#: 31948 Join Date: Jan 2003 Location: SoCal Vehicle: 2004 STi Aspen White	16= doesn't fit

08-19-2003, 10:04 AM	#9
essogas Scooby Specialist Member#: 35703 Join Date: Apr 2003 Location: Toronto, Ontario Vehicle: 2004 WRX STi Blue/British Black 18's	Thanks guys, so it's pretty much true what I've been told. And I did check in the wheels forum and found ZERO.

09-15-2003, 09:08 PM	#10
essogas Scooby Specialist Member#: 35703 Join Date: Apr 2003 Location: Toronto, Ontario Vehicle: 2004 WRX STi Blue/British Black 18's	I was wondering if anyone else had anything to say about this? I'm having trouble deciding on 17's or 18's...

09-15-2003, 09:32 PM	#12
ciper Scooby Guru Member#: 15543 Join Date: Feb 2002 Vehicle: 555 Having a Subaru shop means too many cars	Those posts just show how much misinformation is on this forum. I did a search and the FIRST THREAD on that search had this posting.... Posted by: Leonardo Son of Splinter Moderator "Well, the good thing about having them on the island is I can check. I know for a fact the Sub-Zeros don't fit but the SDT's (Prodrive knock offs) fit and those were 16!!!!" In the same thread Posted by: Konrad Scooby Newbie "according to motorsport specialities, compomotive TH3 15" wheels will fit. I believe that wheel diameter is not the problem but the relationship between the wheel spokes and the side of the monster Brembo's." Im not going to search for anymore. I just now know you guys are wrong.

09-15-2003, 09:41 PM	#13
peczenij Scooby Newbie Member#: 16791 Join Date: Mar 2002 Location: Pennsylvania Vehicle: 2004 WRX STi WRBlue	Sorry if I misunderstood... But, ciper Scooby Specialist, are you saying there are 15 inchers that will fit over the Brembos?

09-16-2003, 11:49 AM	#17
SubEd Scooby Guru Member#: 717 Join Date: Jan 2000 Chapter/Region: NESIC	15's?!?

09-16-2003, 11:57 AM	#18
gforced Scooby Newbie Member#: 38898 Join Date: Jun 2003 Chapter/Region: TXIC Location: North Dallas	All you guys have to do is look at your wheels and you will know that nothing less than 17" will fit. I know a lot of people pop off info like they know what they are talking about and their comments are idiotic. Just wait and see what the tuners start using or ask somone that has changed their wheels.

09-16-2003, 01:56 PM	#19
jagcars26 Scooby Specialist Member#: 2394 Join Date: Sep 2000 Chapter/Region: MAIC Location: Bel Air Md. Vehicle: 2005 Legacy GT wagon 2009 Forester X	Could Leo have meant 15 inch ROTA SDRs?? Just a guess,,,,,im running 17 inch SDRs as a winter setup and i know they fit. Rudy

09-16-2003, 07:29 PM	#21
ciper Scooby Guru Member#: 15543 Join Date: Feb 2002 Vehicle: 555 Having a Subaru shop means too many cars	Im just trying to show everyone that this has been discussed before and others have posted the information. More than one thread exists with information about wheels smaller than 17 inch fitting. If the information is incorrect in the other thread you should post that in responce. I think I read the calipers on the brembos have an effective diameter just greater than 15 inch, meaning the smallest wheel that would fit is something in 16 inch. Cant find that post again though. Did anyone else see it? I also remember reading about others that have ordered 16 inch wheels for the STI. What do they know that we dont?

09-17-2003, 08:06 AM	#23
[email protected] Tire Rack Moderator Member#: 1215 Join Date: Apr 2000 Location: The Tire Rack Vehicle: 800 -428-8355 ext. 4362	there is no way a 15" or a 16" will clear the Brembo's on an STi