Rims

[octothorpe]

No, not *that*. I'm talking about wheels. My TSX was born yesterday, and it's slowly swimming from Japan.

The new K series engines have a 3-axis (3D) ECU, and as such, are a "learning type" ECU, rather than a static map. This means that there is a break-in period that goes a tad beyond a normal 500 mile break-in period, to about 3k miles, so I am not going to add any engine mods until after about 5k.

This leaves me with suspension mods, my personal favourite! I know I'm going to go with the Koni Yellow/Eiback Pro Kit combo as I have on my Accord, but I've *got* to ditch the stock rollers. the car is *heavy*, so any weight I can take off (without too much sacrifice), I will. However, aesthetics weighs in heavily as well. I'm down to these two rims:

The OZ Racing Superturismo GT, weighing in at 20.7lbs


Or,

The OZ Racing Ultraleggera, weighing in at 17.6 lbs.


I'd probably go with a 17", as an 18" rim would weigh more, and there would be more rotational mass. I am however, going to go with 235R45 rubber, which is going to add a bit to the overall weight, but should improve traction, keeping the power on the road.

The stock rims are 25lbs each, so both choices offer serious weight savings, however, I am concerned that the Ultraleggera may be *too* light to deal with the ass-tastic roads we have in CT. Bent rims suck.

I'm also looking at wind resistance. Aerodynamically, the TSX is one of the best non-exotic production cars on the road. Wheels are a factor in that. I believe the Superturismo GTs may be better in that regard, although I am not sure I'll be going so fast for long periods of time for it to matter. I do Solo 1 and Solo 2 stuff mostly, and I don't usually go above 60mph. "Real" track days, however, I can easily go over 100mph, and that may start having an effect.

So what do you think?

Comments

[notdefined.livejournal.com]

#1 but only because they appeal to me.

[notdefined.livejournal.com]

I have to admit, I gave up learning about automotive things when electronic ignition came on the scene. I have done some reading today, just to not be too much of a dolt and to figure out what an ECU was since I figured it was not a unit of currency. During my searching I came across a bit from Acura that says your vehicle is a drive by wire!!!!??? No mechanical connection between the accelerator pedal and the throttle! There are also a lot of electronics between the human and the machine. How much of that are you going to leave intact?

[theoctothorpe.livejournal.com]

Yes, it is a DBW system. The throttle wire goes to a little black box, which then goes to a traditional throttle body. I plan on bypassing the DBW system *very* shortly after the break-in period. It's a $5 modification =). It's not *quite* as annoying as the delay in torque in an automatic, but it's a decided feeling of disconnectedness.

[notdefined.livejournal.com]

I was trying to wrap my brain around the idea that you would give up direct control of the throttle and my ends would not meet!

[squalidbear.livejournal.com]

I vote for the OZ Racing Ultraleggera rims. Sexy and light.

What are the wheel bolts made of, an aluminum/magnesium alloy? When I had a Porsche 911, I took off one of the wheels and the five wheel bolts weighed about the same as one steel bolt from my Prelude. Another component in the drive to reduce unsprung weight and rotational mass...

[theoctothorpe.livejournal.com]

Because the TSX is an ordinary production car, the bolts, I would imagine, are steel, and the lug nuts are steel/chrome (heavy), to the best of my understanding.

But yes... I forget the actual formula, but something like 1lb of unsprung weight is roughly equal to 5lbs of sprung weight. We wish to reduce as much as possible the unsprung weight. I don't think I'll go CF bonnet/hood, nor rear deck lid, as unless it's from Spoon, it's not going to fit 100%, and *all* CF parts are prone to flapping at high speed, and need to be pinned down.

[squalidbear.livejournal.com]

So the hubs have threaded bolts sticking out, rather than holes that you put bolts in ...?

What happens if you put aluminum/magnesium alloy buts on steel bolts? Do they weld themselves together?

[theoctothorpe.livejournal.com]

Yes, although you can, in fact, take those bolts out. That's how you change the rotors…at least I think you need to take them out to change the rotors.

As for mixing metals, I would say that's a no-go. Just as you can't weld dis-similar metals, threading different metals together sounds like a recipe for disaster, as they'd expand at different rates.

Check out my expertise and fear me!

[rogueboi.livejournal.com]

Option #2 are prettier, but they do have something of that "breaks real easy" look to them...

Why must pretty things always break so easily?

*sigh*

Re: Check out my expertise and fear me!

[theoctothorpe.livejournal.com]

You're pretty, and you don't break easily…

;-)

Re: Check out my expertise and fear me!

[rogueboi.livejournal.com]

That's one hypothesis. You went to fancy science college, so I'm guessing you know what it is that you must do... ;)

[beastbriskett.livejournal.com]

The Ultras. I like the paired, tapering spokes.
They're bitchin'!

[greatbearmd.livejournal.com]

I'd go with the Ultraleggeras, since I was going to get a version of them for the MINI before settling on the SSR Competitions in 17x7.5 and about 13 pounds a pop.

I doubt either wheel will factor much into spoiling the aerodynamics of the car. I prefer an open wheel for maximum brake cooling. The vane spoke design of these will fan plenty of air through your brakes.

[theoctothorpe.livejournal.com]

Mmmmm 13 lbs! And you don't fear bending the hell out of them?

I was also considering the Enkei Competition wheels that the RealTime boys use, but I can't seem to find a place that sells them.

[greatbearmd.livejournal.com]

I'd worry more if I were using 18s and a 35-series tire, but with 215/45-17s there is enough sidewall to cushion any nasty impacts I might run into day-to-day. This is not to say that I might accidently clobber the rims in a big pothole someday, but already I hit some pretty heavy holes, seams and joints and I have yet to spoil the rims.

Sadly, it appears SSR is not making this series of rims anymore. The antracite colour matches the paintwork of the car pretty well, making them seem like custom matched.

[hossinseattle.livejournal.com]

I think you're really in to your car.