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Discussion Starter · #1 ·
Why only sloted rotors and four piston calipers? Because that is what is best for what we are doing with the car:) Mike at Wilwood helped my decide what the best system was for our street driven, soon to be very fast, autocrossed alot, track day car would need and would hold up under all conditions properly.

This is the stock tC system with sloted rotors instead of plain or drilled, the brake pads were selected for the intended use as well, I forget which ones right now, too tired to look in the box. We are going to use their EXP 600+ brake fluid and of course SS lines. We still need to get some rear lines made up.

These are really going to fill out the front wheels, Enkei RPF1 17x8, actually a very close fit, closer than some 16" designs I have seen.

We may install them tomorrow or wait a couple of days until done with other projects and start pulling the tranny for the LSD, flywheel, clutch, motor mount, front Hotchkis sway bar install we are doing, all the parts are finally here.

After this the car will be completed for handling and braking.

Except the second set of RPF1 wheels for slicks all around:)


I can hardly wait for the turbo now!!!!

Rick
 

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Discussion Starter · #3 ·
Thanks, I have had brakes I was never quite satisfied with on other project cars so this time went with a company with a huge history for doing things right:)

I really only "need" them for track days on road courses but like good brakes for just about all other things I like to do with my car.

And, they look so sweet, not bling at all, black hats, black calipers, not drilled, they are for real performance on a car we are building to be really fast all around, not some trailer queen or max HP dyno ***** either;)

Rick
 

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You got the GT rotors; they're vented and slotted, but not cross-drilled. They should handle higher temps and heavier pressure better than the SRP rotors. I ordered the same kit you did with the four-pot forged Superlites but since my tC's a daily driven street car I went with the SRPs (cross-drilled instead of slotted). I ordered my front kit along with Wilwood braided steel lines from Precision Brakes Company and it should be arriving in a couple weeks!

Now, I do know that the limit to my car's braking ability is the tires and not the brakes, but I just haven't been fully satisfied with the brake feel and modulation on my car; I feel as though I'm having to press the pedal farther than I like to get the amount of pressure I want a lot of the time, so I'm hoping the braided lines, if not the larger diameter rotors will help that quite a bit (in a way, I prefer quicker brakes/less pedal travel for more brake force, or should I say, more sensitive/more difficult to modulate, as I am confident in my ability to modulate precisely even with quicker brakes).

It would seem to me that simple physics dictate that by using a larger diameter brake rotor, less pressure from the caliper is necessary (given the same exact pad, but then again I'm changing pads too, obviously) to apply the same brake force. Yes, I do know that by cutting down on pedal travel for the same brake force, I am cutting down on modulation precision and simply making it easier to lock up the brakes/cause ABS to fire, but it's really a subjective/preference thing--I actually want tighter brakes and I am perfectly confident that I can handle them as such.

Please feel free to correct me on that, anyone, as I'm just going by pure theory and jest--I have no hard data to back up my own conjecture. I am certainly not going to lie about one thing though--I really like the looks of this kit compared to even the stock pieces with painted calipers (why else would I go with SRP over GT?).

Wilwood doesn't make a rear kit for our car, so I am having Precision Brakes fab me a custom rear kit; 12.9" SRP rotors and four-pot forged Dynalite along with Wilwood lines. The custom fab job will take them four to five weeks longer.

I can't wait to get them in!!! Precision brakes is doing free powder coating this month (red, white, blue or yellow) but I decided to stick with the stock black w/white lettering from Wilwood--I felt it would go nice with my SSM tC, and it seems that everyone else has red (except Rick, of course), so why not try something different?

Say, Rick--do you think these brakes will fit the stock 17" wheels that come with our car, or should I decide seriously on something 18"? I really like the look of the stock 17" wheels (other than the fact they're six-spoke wheels that attach with five lugs), and have been extremely hesitant in buying 18" wheels & tires unless the brakes really don't fit. I've been looking at a bunch of options (the Enkeis that Toyota sells, Axis Reverbs, Axis Hiros, Axis Decades, BBS CVs, Kazera KZ-As, Gram Lights 57Cs) but haven't really settled on any since I'm really hoping to keep the stock ones (I got lucky and received the Yokohama S32As with my car, rather than those dreaded Bridgestone RE92s). Precision Brakes has not yet sent me the templates for test fit. Haven't decided on 18x7.5 or 18.8, but I think that decision comes more with exactly which wheel I settle on.

As for tires on the 18s, I'm almost completely settled on P-Zero Nero M+S. New York snow is a genuine concern to me, and I'm far too lazy to swap out three-seasons tires for Blizzaks. Living in an apartment with minimal storage space, I'd also have no idea where to keep my spare wheels & tires during their off season.

-Ed

PS Btw hi all, I'm new here! *waves*
 

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Originally posted by Plissken@Jul 16 2005, 10:34 PM
(Welcome to the site)
Thanks!

I promise not to make such long posts...

...all the time, at least (sorry, it's a habit of mine).

-Ed
 

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Originally posted by Plissken@Jul 16 2005, 10:40 PM
Make them as long as you want!
Don't know about that...I actually moderate a different forum (SilentPCReview, anybody here know of us?
) and have made some insanely huge posts in there--even whole threads made up of insanely long posts!

But then again, those posts were filled with not just text but temperature data, power data, subjective noise notes, benchmark results, photos and other stuff...

-Ed

PS Speaking of that, I better just get back on topic...
 

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Discussion Starter · #9 ·
ED,
Welcome:)
I will have to let my son know about the site you moderate, he is getting more and more into the ether (spelling) regions of PCs all the time;)

Not sure if they fit the stock wheels, if not it would be the face of the caliper hitting the spokes if anything, spacers would cure that but I sure do not like spacers all that much.

I have about 1/2" clearance from the front edge of the caliper to the wheel rim and these wheels are rather small in diameter in that area, much more so that most 17's (17x8 Enkei RPF1 +35mm)

These brakes really stuff the wheels full, the design of the wheel is such that it makes the brakes almost look to big, lol! I would acutally have gone with smaller rotors if they had a mounting hat available;)

I need some kind of drag wheel, preferrably in 15" for the occasional night at the strip, may have some custom steelies made, probably going to end up with 16's so will go search for real slicks in that size, just never bothered before. I could always swap to stock brakes for drags but that is alot of hassle to do.

Mainly AutoX, Road Course and a few canyon runs here and there is what the car is setup for. The road course runs are really the only thing I needed the brakes for in my opinion with the exception of looks for some shows we will be in and going for some mag articles(I have some good contacts in that department:)
 

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Hmm, if it's an issue of the calipers running too close to the back of the spokes, I would think going for wheels with an even tighter offset, no matter what diameter they are, would actually be detrimental, no?

Here's another query for you: Let's say we have a wheel offered in multiple offsets; which one mounts the wheel farther in (i.e. closer to the caliper), +35, or +45? From what I've read, the stock 17" wheels are +45mm offset, so if I have a brake clearance problem, I need to know whether to go downward in offset (+35mm, for example) or to go upward/use a spacer (I haven't really seen many wheels in 18x7.5 with offset greater than +42mm).

Thanks again; and here I was, originally concerned about clearance with the inside of the rim!

-Ed
 

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A bigger positive number for offset means more room for the caliper and a wider track. It can also mean the centerline of the wheel is not in the right place in relation to the wheel bearing and create a constant side load on it that will seriously shorten its service life.

Your suppositions about brakes are dead on the money. I would prefer you had prior experience with larger rotors. It's easy to screw up a brake system by using the wrong master cylinder diameter to caliper piston ratio combined with larger diameter discs. One of the cool things about larger diameter discs is they don't need as much swept area to create torque, which is similar to the concept you described as needing less pressure. Since there are a dozen or so variables to work with, it may take some trial and error to find pads that work, and possibly a master cylinder change to make the brakes sufficiently sensitive and still provide the stopping power you want. Of course, that's really just a matter of experimentation and cubic dollars to swap out parts until you get it right.

Good luck with the new setup, and I hope you don't have rotor cracking issues. It doesn't sound like you plan to do track days with the car, so that will help, but I'm not a big fan of drilled rotors at all. I've seen too many with cracks after a single track session.
 

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Discussion Starter · #12 ·
I was fortunate enough to have direct help from Wilwood in selecting not only rotor size but sloted versus drilled(already knew I wanted sloted) because we are doing track days:) And we picked out 4 pistons instead of 6 calipers, piston diameter so the stock master cylinder would be matched even the appropriate all around brake pads though that will take some autox, track time to nail it down exactly.

The width of the pad contact area is narrower than the stock rotors as well, they had this pretty well worked out and just made minor adjustments to what my kit would consist of. Still, great to work out most of the issues before even getting the kit shipped out:)

As for the rear, they confirmed my intentions of going for a rotor upgrade(more for cosmetics) and brake pads to work well with the fronts. I had already painted the rear calipers black as knew I wanted black front calipers so it is complete out back except the SS lines. Of course I really do not need them but just the same, I will change to them because I want to:)

Rick
 

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Thanks guys; that's pretty much what I really needed to know. I am pretty sure the brakes should fit the stock wheels, which have a hefty +45mm offset; in case they don't, I think a spacer would be the least costly solution, since I haven't been able to find good looking 18" wheels with a greater offset than +42mm.

I was aware of the concern over cracked rotors due to the crossdrilling, but I figure that with the sheer number of available crossdrilled disc brakes and kits out there, it must take fairly aggressive driving, such as that in serious autocross or circuit competition, to run into problems, and that's far from the way I will be utilizing the car, but I do appreciate the concern.

Now if I did plan to go into mild competition, I'd probably do something more like a new Mazda MX-5--and in that case, I'd be doing slicks, a roll cage and GT rotors instead of the SRP.


Getting back to the clearance issue one last time; does anyone know of any 18" wheels with 5x100 lug pattern that comes in offset higher than +45mm? I haven't been able to find any, buy maybe I don't know the right place to look?

-Ed
 

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Discussion Starter · #14 ·
I think there is a bit of confusion here;) Lower number offset will puch the rim and spokes out away from the calipers for more clearance.

Enkei makes several wheels that come in 18x8 +35 that fill out the wheel wells very nicely and easily clear the rotors of the brakes you are talking about:)

We have 17x8 RPF1 +35mm and plenty of clearance of the spokes, only about 1/2" from the caliper to the rim though but these wheels have a small diameter section in the rim in that location for strenght. These are very very strong 15.6 lb wheels, I know from experience just how strong they are;)

http://www.enkei.com/racingseries.html
 

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Originally posted by Lance+-->QUOTE (Lance)
A bigger positive number for offset means more room for the caliper and a wider track...[/b]
<!--QuoteBegin-Rick

...Lower number offset will puch the rim and spokes out away from the calipers for more clearance...
You're right, now I'm confused.


According to Lance, to get more room for my caliper, I'd have to get a higher positive number than my current wheels' +45mm offset, i.e. +48mm or +50mm.

According to Rick, a lower number offset is necessary to push the spokes and rim away from the calipers, i.e. lower than the stock +45mm, like say +42mm or +35mm.

Uuuuhh........

-Ed
 

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I'm thinking backwards, Rick is right. +35 is a wider track than +45.
 

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Alrighty, got my wheels (Privat Profil by Konig), tires (Avon Tech M550) and brakes put on (only the fronts so far); EDIT: *snip* click here for my review of these brakes.

Rick, what wheels are you guys using on your tC?

-Ed

EDIT: Forgot to mention the car sits on TRD sport springs, so these pics are after the minor drop.
 

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Discussion Starter · #19 ·
Enkei RPF1, 17x8, +35mm, 15.6 lbs each, perfect fit with 235/40/17's but will rub a bit in the rear with near zero camber I have dialed in and a full load in the car.

I am testing different setups to dial in some slight oversteer;)

Rick
 
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