18's

[Dunrick]

If your 50 series has as much sidewall as the 60 (stock) then overall you do have more contact patch....shit dude....you get all einstein and what not - breaking out mathmatical equations...haha I dig that shit

rock on!

[chunky]

Originally posted by Dunrick
If your 50 series has as much sidewall as the 60 (stock) then overall you do have more contact patch....shit dude....you get all einstein and what not - breaking out mathmatical equations...haha I dig that shit

rock on!

haha. not really einstien, but math helps break down a lot of language & comprehension barriers. It finally got my point across in a way that made sense to you!

And it also helps figure stuff out when you don't have the luxury of just experimenting with the objects in question in front of you.

[mental]

OKAY OKAY... I MEAN REALLY THOUGH HERE IS MY QUESTION...


HUH??????? I AM SOOOOOOO CONFUSED!!!!!

[chunky]

Originally posted by mental
OKAY OKAY... I MEAN REALLY THOUGH HERE IS MY QUESTION...


HUH??????? I AM SOOOOOOO CONFUSED!!!!!

about what?

put it in question form and i'll do my best to answer.

[02SilverSiHB]

Originally posted by chunky


about what?

put it in question form and i'll do my best to answer.

I'm starting to lean more towards what you are saying. I thought about it for a while. I have to say, it does seem that 15's would be better, as long as you have a wide enough tire...which 225 is definitely wide for us. When someone asked, then why are the high performance cars using bigger wheels...well they have usually way wider than 225, so 15's wouldn't be pratical for that size tire, that I know of.

Also, it's proven time and time again, that 15's will give you less rotational mass. So, lightweight 15's with wide tires seems better than more rotational mass with 17's.

That less rotational mass will help when cornering, I would think.

[chunky]

Originally posted by 02SilverSiHB

I'm starting to lean more towards what you are saying. I thought about it for a while. I have to say, it does seem that 15's would be better, as long as you have a wide enough tire...which 225 is definitely wide for us. When someone asked, then why are the high performance cars using bigger wheels...well they have usually way wider than 225, so 15's wouldn't be pratical for that size tire, that I know of.

Also, it's proven time and time again, that 15's will give you less rotational mass. So, lightweight 15's with wide tires seems better than more rotational mass with 17's.

That less rotational mass will help when cornering, I would think.

lowering rotational mass helps during acceleration. Greater rotational mass is only good for one thing - slightly better gas mileage on the highway, b/c it takes less energy to keep them going as they have a lot more inertia than wheels with less rotational mass.

However, lowering unsprung weight helps during cornering. Reducing unsprung weight pays off big on the track.

By getting light wheels, you kill two birds with one stone.

[Dunrick]

With all this said, whats the point of low profile tires and larger wheels? I know its not just looks

Yeah they are better for acceleration and gas mileage...

But you guys are making them to be too good - I just dont see how 15" wheels on 50 series tires are the king...

there is a reason for low profile tires and 16/17" wheels

I know they handle better.....You can get them just as light as 15"...maybe a few lb's diff....but thats it

[anjapower]

NO. Smaller is better. Bigger wheels are only needed to clear bigger brakes. That's it, that's all man, it's just fo decorashun.

[chunky]

Originally posted by Dunrick
With all this said, whats the point of low profile tires and larger wheels? I know its not just looks

Yeah they are better for acceleration and gas mileage...

But you guys are making them to be too good - I just dont see how 15" wheels on 50 series tires are the king...

there is a reason for low profile tires and 16/17" wheels

I know they handle better.....You can get them just as light as 15"...maybe a few lb's diff....but thats it

when you need a bigger overall wheel/tire diameter, then you'll need bigger wheels.

But for the size wheel that the si uses, a 15" is fine. The RSX gets a 16" b/c it's gearing was planned around a wheel with a larger overall wheel/tire diameter in mind. Corvettes & vipers get bigger wheels b/c they need a much larger overall wheel/tire diameter.

But a corvette z06 with a 295/35/18 tire has a sidewall hieght of 103.25 mm v.s. the 112.5mm sidewal hieght of my 225/50/15. There is only 9.25mm difference in sidewall hieght, even though the corvette has 35 profile tires on 18" wheels.

So while it SEEMS like you have to go to a lower profile tire/larger rim, it's not always the case. The actual sidewall hieght is a much more important factor, and with a 15" tire, you can get a sidewall that is short enough to where it can be made very very stiff. Going to a 16" or 17" isn't going to get you a sidewall that is that much stiffer.

[tony speed]

Originally posted by chunky
18's for show, 15's for go.

anyone buying 17's or 16's is just confused, or wants the show, but can't afford 18's.

2 words.....brake clearance
4 words.....more width==better handling
final word.....forged 17s 12 lbs...stock 20 lbs

[mhx]

17'in rims would help autox people correct?

I mean you can get a Wider tire and put more rubber to the ground getting your better traction?

also could help your stop faster since there is more rubber to the ground.

what yall think??


chunky makes a good point to about the tires being able to flex
more if the height of the tire is taller

small sidewalls = very very cauious driver not to HIT ANYTHING... been there done that!!

[glw]

Originally posted by mhx
17'in rims would help autox people correct?

I mean you can get a Wider tire and put more rubber to the ground getting your better traction?

also could help your stop faster since there is more rubber to the ground.

what yall think??


chunky makes a good point to about the tires being able to flex
more if the height of the tire is taller

small sidewalls = very very cauious driver not to HIT ANYTHING... been there done that!!

its all about rotational inertia... there is an article on it in the latest grassroot motorsport magazine. i need to read the article a couple more times but here is a summary..

good=less unsprung weight (lighter wheels and tires, brakes, etc.)

less weight usally equals smaller wheels, but you may be able to find some forged 17" much lighter than some cast 15" wheels. my understanding would be that the lighter forged 17" wheels would be the best choice vs. the heavy cast 15" (all else equal).

i've been eyeballing the velox progear wheels --- 11.5 lbs for some good looking 17" wheels... cost about $350 each though.

[mental]

for AUTO X i would go with 16s on our cars and for the strip i would go with a really lite set of 15s and for the track i would highly recommend 17s or 18s and by track i mean a motorsports track with real corners and corners you can apex! not a parkinglot which would be auto x... lol...but yeah for auto X you really want good acceleration and alot of break clearence which 16s allow for and for the strip you need 15s with like a 225/45/15 for a lot of grip on the ground and not a whole lot of rim for the motor to spin, and one last time for the track 17s and 18s help you to carry your momentum through turns and put a great deal of tread to the ground for turning grip!

[staticflo]

personally i think 17's are the perfect size for the ep as far as looks 18 i feel look a little to big but with the right suspension work im sure they can look sweet anything less then 17 is "fuken gay" and low profile tires are cool big tires with 17 or 18 inch rims would look stupid..