I'm considering buying a Stoptech 13" or 14" BBK front and back for my 05 6MT G35 Coupe. I plan to start tracking my car next year at HPDE events, and I've read that the stock brakes will experience fade and warping. Should I get the 13" or the 14" kit or do I even need the rear kit? TIA.

 

think of your eventual HPDE set up. If 17" track wheels with R rubber is the end game to be low and light in wheel wells (weight of wheels & brakes) then 13" will be the fit.

 

I was at the same boat with you, but due to financial reasons, I ruled out purchasing a BBK at this moment. If you are fairly new to tracking your car, some high temp brake fluid, track pads and SS brake lines should give u a pretty good setup at very cheap. You'll probably wanna save some $$ for better rubbers.

If you have a 05+ G with sport package (bigger brakes), that's even better.

 

I'm leaning towards the 13" since I already bought 17" wheels for the winter. I read a thread on here that my 17" wheels (MB Motorsport 17x8 w/28 offset) might be able to fit the 14" Stoptechs. I'll have to wait until Monday to print out the fitment guide from Stoptech to see if 14" will fit.

If the 14" happen to fit my 17" wheels, I'm just wondering if the heat capacity of the 14" are that much better than the 13". The prices difference is only $200. I realize the 14" will be heavier and might affect the handling a tiny bit. If the 14" are that much better, and they won't fit my 17" wheels, I'll then have to think about getting 18" wheels for the winter. I think the 14" should fit the OEM 19's. I'll find out on Monday.

 

I'm definitely a newb to tracking or even autocross. I'm finally getting chance to try it out with my G with 6MT.

You're right about the price of BBKs. I'm not trying to make my car faster or look better. I just want to learn to drive fast and smooth, and keep it reliable. It's my daily driver for now.

Have you tracked your car with the upgrades you mentioned? I have the G35 coupe 6MT that come with the 19's and the bigger rotors (12.6" front and 11.xx" back). I just don't want drive to the track, do some runs, and then have my brakes warp so bad that I'll have to get new ones.

The other option would be to replace the OEM rotors with Stoptech Aerorotors (if and when they make them for the size). I wonder if that'll take care of the fade issue.

 

Before you blow the budget on a brake kit you may want to try out the stock brakes with upgraded pads first. Get some quality track pads (plenty of on line vendors like http://www.raceshopper.com ) with at least a 1400 deg. (F) temp rating. Swap and bed them in the day before each track day, and run those for your first several days. If you smear the pads badly and/or boil your fresh upgraded fluid you're probably ready for a brake upgrade too.

I've got an auto '04 G with 17" winter/track rims and undersized stock brakes. I got the 13" Stoptech kit and have a season on it now, the performance has been excellent. I do have excess pad deposits after most track days, but that may indicate a need for better pads/ducts more than any deficiency in the brakes themselves. I use the Stoptechs from April through November and throw the stockers and snow tires on for the winter.

 

As others have said, you may want to try some race pads and fluid first. That said, for most fairly quick drivers the stock base rotors simply don't offer enough heat capacity (even the stock Brembos don't once you start going fast).
I'd recommend a front only kit at first. If you feel you need a rear kit, you can always add our 2-piston kit later.
As for the 13 vs. 14 inch issue...some things to consider....Decide what wheel and tire package you want. There are more choices of good race rubber in 17's if you want to run R compounds eventually. 17 rubber is also cheaper. A 17" package is also lighter by a few lbs. in most cases, and the 13" brake package is lighter. I run the Enkei RPO2J wheel...the RPF1's are also very nice. They weigh about 17-18lbs. per wheel...in the $200 range for each wheel as well.

I personally run our front 13" kit, and I run fairly quick on the track. I've faded them only a couple of times on the track...mainly when running back to back sessions with a pro driver. The Unitech Z's in Grand Am Cup now run our 13" kit with great success, and rarely run out of brake. If you do need more cooling, you can do some duct work.

I guess my reco is unless you plan on running an 18 wheel for some reason, the 332mm kit should be sufficient. If I was only going to run 18's or larger, I would get the 355mm kit just so I had the extra heat capacity.

Also, I didn't ask if you are running stock weight and power levels. If you are going FI, taking off a few lbs., and running R compounds, then you probably want the 14" kit. If you are running near stock power levels with R compounds, you should be fine on the 332's.

It also depends on what tracks you're driving. If you run tracks that are notoriously tough on brakes, you may want to just get the 355's just for piece of mind. Most of the stuff I drive here in SoCal (Big Willow, Streets of Willow, Buttonwillow) is easier on brakes than what I ran into back east (Watkins Glen, Pocono).
I hope that helps.

ps Get black calipers if you want them to look purty after hard use. All paint will change color...the black hold their color the best.

 

I'm running a front only 13" Stoptech kit with the MB Motorsports Weapons in 17x9 and Falken RT-615s rubber. I'm an average intermediate driver and I find the setup sufficient whereas I was fading the stock setup with upgraded pads. Only downside is that the rear pads go pretty quickly, luckily they are cheap and easy to replace

 

I'm using the 355mm BBK. The track I drive at isn't very hard on brakes, so I sometimes have a hard time getting my race pads up to temps. My car is practically stock. In my case, I would have been better off with the 332mm BBK. The 355mm is a heavy rotor tpp, and you will feel some loss in acceleration. I looked for a 17" wheel for some time, but gave up, and bought 18" wheels for the track. 18" r-comps are very expensive.

 

Thanks for the replies guys. I think it might be worthwhile to try to stock brakes first with upgraded fluid and race pads. Since I've never done track events before, I might find out I'm too slow to need bigger brakes. Who knows, I might not even like the HPDE events. Not likely though...

Since I live in MD, I'm going to singn up for the Z Club/NASA events at VIR and Summit Point at WV. My brother's going to start doing the same with his Z06. I'm looking forward to it.

When I decide I need to upgrade my brakes (front or both), I'm definitely getting Stoptechs. They sound like a customer-focused company with a great product. I'd also probably get the 13's so I can keep my 17" winter wheels. No sense in wasting money. Thanks.

By the way, my car's completely stock. No plans for any power upgrades. Just need to learn to drive better.

 

I know that you have made a decision to delay the BBK, but I wanted to add one more option to those making a choice between 13" and 14". The caliper for the front 13" kit is the same as on the front 14" kit (for Stoptech). So to upgrade from a 13" kit to a 14" kit only requires new hats and mounting brackets. I recently upgraded to a 14" front kit.

Also, for those making a decision about getting a rear kit. It is not manditory and there is no need for anything greater than the stock brembos let alone a 14" kit.

 

Same caliper casing, but are the pistons the same size? I was thinking of doing the reverse...going from 14" to 13".

 

StaticCling,
That is incorrect information. The calipers on the 332mm and 355mm are NOT the same. They look the same on the outside, but the piston sizing in those calipers is different to optimize balance. The calipers in each of those kits is designed to work specifically with the rotor size included in the kit. The pistons that are used in the front calipers on our 355mm kits are smaller than those in our 332mm kits.

By using the calipers from your 332mm kit, and combining them with a larger diameter 355mm rotor, you have shifted bias towards the front of your car. You will now be underutilizing your rear brakes, and the full tractive capacity of the rear tires. Since you have shifted bias to the front (a stable condition), the car will still be safe, and you will have more heat capacity in front...it will not be optimal however.

Changing these three variables with all else held equal will alter brake torque:
Rotor Diameter
Caliper piston size
Coefficient of friction of the brake pad

This is the big difference between what we do vs. our competition. Let me know if you have any further questions. We definitely recommend only using the components with the parts that ship in our kits. As I said, many of our calipers look the same on the outside, but the piston sizes vary anywhere from 28mm to 44mm in a wide array of combinations...a huge difference in torque output!

G_Man,
Thanks for the kind words. We try to do our best to help our customers and competitors' customers...despite constantly being ridiculed and attacked for doing so!

 

question answered, thanks

 

That's one of the big reasons I plan to get Stoptechs (someday in the future) when I can finally upgrade things.

What kind of ridicule do you get? That seems pretty crazy to me; I always appreciate good information.

 

+1 for Stoptechs. I have a 2005 G35 and originally had some fitment issues with my rear caliper brackets. However, Matt Weiss there spent the time to check out my car and test the brake bias to make sure everything was kosher. I've used the 4 wheel 13" kit at the track this past weekend with race pads (Pagid Orange) in the front, and my braking was absolutely stellar. StopTech's products and customer service are top notch. I highly reccomend them.

 

G_Man... I concur with your decision... Heed the advice mentioned before about good pads and fluids... with these additional suggestions:

1) For your first couple events, don't go full race pads. They are cost prohibitive, and need to be at certain temperatures in order to work effectively. February in VA is cold, as you know, and you want your brakes at their optimum temperature early. VIR Full is pretty easy on brakes - they will cool off quickly in February.

2) Brake fluid is the more important issue in my opinion. Definately go with a synthetic, high-temp race fluid like Motul 600 or AP Racing. There are others as well. Do not use silicone based, it will ruin your brake system

3) Technique... beginner track drivers have a tendency to 'ride' the brakes going into the braking zones. Its a very natural tendency - this is what you do on the street to keep things smooth. DON'T do this!! This should be one of the first things your instructor will teach you. This one simple adjustment will keep you from overheating your brakes pre-maturely. You should be braking the hardest (without locking up or ABSing) in the shortest amount of asphalt. Its called threshold braking and should be the first technique learned when starting HPDEs IMHO.

Glad you're choosing our event to start with... hopefully the weather will cooperate

 

+0.999.

Being the passenger on your last track event when your brakes failed completely... i'm still trying to get the stain out of my pants by the way...
im glad you got your new BBKs!!! (and the Oranges)

now... go get some 18s and try to catch up!

 

Stack, Hayaku -

Thanks for your advice. I'm going with your recommendations. They make sense to me. I'm going to wait until the week before the Feb. VIR event before I decide to sign up. I want to see the weather forecast before I drive five hours to and from the track.

I've been so excited about tracking this car since the day I got it. Then about a few weeks ago, I noticed that my car had been burning oil (>1qt/3k miles) and I only have 3020 miles. I think it's taken my mind of the tracking and fun part and got me worring about longevity issues with the engine. What a pain!

I'm going to get an oil change at the dealer and see what happens over the next 1-2k miles. If it gets worse, I might ask the dealer for an oil consumption test. I figure there's no point in doing it now since 1 qt/3k miles doesn't seem too excessive, and I don't think they'll do anything about it. We'll see.

 

That's a lot of oil your engine is consuming. I would send a sample in to blackstone labs (www.blackstone-labs.com) and have them do an analysis. Based upon the metal content (type and quantity), they may be able to determine your problem. It's only $20 for an analysis.