I'm 99% sure he has a fitment for the ST40 application since that caliper is utilized in so many Stoptech kits. It seems that Cobalt launched a new and improved website within the past 48 hours, but not everything is functional and it doesn't list anything for the ST40. I'll call Andie today (since I need to order rear pads) and I'll ask him for you. As for price, well, Andie is good about being "creative" with discounts to repeat customers.

I really only have one complaint about the VRs, and that being the pads have almost too much of a linear feel, but these pads require you to be smooth on the brake pedal. As you might recall Adam, sometimes when I got on the pedal too aggressively, I would occassionally go a hair deeper into the corner. Smooth is good.

When it comes to gear oils / tranny fluids and using OEM internals, I'm a bit conservative (having ruined two synchros on my previous car with Redline), so I stuck with the OEM fluid. Once I put a Nismo diff / 3.9FD in, then I'll likely us what BJ recommends, that being Mobil 75W/90 Syn.

 

The PF01s are expensive ($250-270 is about the best I've seen for the ST40 caliper) but they last a really long time (at least with all the cooling I have on there). I can do a whole season on 2 sets of brake pads. That's something like 15 days on a single set. Which actually makes the per use cost pretty affordable. My rear pads by comparison are only ~$50 but they last 3-5 days so the cost is actually about the same.

For the PS fluid overheat problem, I've just run shorter sessions (i.e. I come in early - I don't pay for track time so it's not that much of a scarce and precious resource to me) but I'll probably buy the Nismo cooler over the winter.

I'm running redline in the stock diff and tranny. Haven't had any problems to date but I haven't necessarily paid very close attention either.

 

I've had good luck with Carbotech Panther + pads, F & R. I also run ST40 F calipers but with Brembo track rears. NO problems, but I probably will try a better/different pad next year. I also run HUGE F brake cooling ducts!

Knock on wood, I've not had any problems with my PS fluid overheating. MAYBE, I'm just slow. But I've turned better lap times than some other Z's that have boiled their fluid.

I also swicthed to Redline trans & diff fluids when I added the Nismo finned diff cover. No problems that I'm aware of.

I MIGHT get a Quaife LSD for next year though.....I'll find out soon what they recommend.

 

Numerous topics here...

I switched to the NISMO power steering cooler as well after numerous problems...problem solved...no more boiling over in 3 weekends.

I run Redline in my Diff, per Unitech Racing's recommendation. I started with the stock oil that came with the NISMO diff, but it was horribly noisy. I switched it out, and smooth sailing...also added the finned cooling cover.

Another excellent pad I would recommend is the Pagid RS-14 (black compound). I actually like the feel better than the PFC 97, but I haven't personally tried the 01 yet. I find the RS-14 much easier to modulate. It takes heat well, and it lasts a while. They are about $208 or so if I remember correctly, so a good buy. Used by many pros for a long time.

 

I've taken some pictures of the Nismo PS cooler, but I seem to have misplaced the PC cable for my camera. I'll post the pics up when I find the cable and can get them uploaded.

Basically, the Nismo unit has a longer cooling piece than the stock cooler. You can see the stock cooler if you look through the grill in front of your bumper, on the lower left side. It's the horizontal cooling unit in front of the radiator (you can also see it if you open the hood and look down in front of the radiator.) Essentially, the OEM unit has a 5.5 inch cooling piece, whereas the Nismo one has a 9.5 inch one. It may not sound like much (and to be honest, the unit doesn't look like much,) but it does the job.

Hope this helps, but I'll try to get those pictures posted soon.

Gary

 

Wow - lots of good discussion, so more questions

John - You said, I'm not sure what you mean here. Are you saying that getting too aggressive with the pedal triggered ABS (because weight hadn't shifted to the nose yet), causing you to end up deeper in the corner? Or?

So we've got recommendations for the PF01, Cobalt VR, and Pagid Black... Gary - I know you mentioned having tried quite a few options and came to the PF01 as the best choice. Did you try all of those? I tried Pagid orange for my first two days with the Stoptech kit, and wasn't thrilled with them. They actually seem to be a fairly good combo pad for beginners/intermediates who don't want to swap pads for the track. They don't sqeal at all, and have only gotten a shudder in the last couple days as the temps have dropped into the 30's. My only real complaint was depositing under high temp. Given the significant price different between the PF01 and VR/Black, I'll probably give either the VR's or Blacks a shot when the Orange's are done, depending on availability and price. Anyone know if one is more rotor-aggressive than the other?

Topic #87 for this thread... Tranny/diff fluids. I think I'm going to go back to the Mobil fold. I've used Redline in the last couple of vehicles I have, but more and more I find it difficult to believe that this (relatively) small company employs better petrochemical engineers than Mobil. I've always been happy with their engine oil (except their reformulated 15w-50 in my motorcycles), so since I'm due (thanks for the alert about the diff John!), I'll mosey down to the local advance/autozone/walmart and pick up what I need (instead of the 20mile ride-so-the-dealer-can-gouge-me experience for redline).

Sounds like the Nismo PS cooler is the simple way to solve this problem. I haven't had it happen to me yet, but I'm running Azenis Since it is inexpensive, it ought to be nice little winter project. Any install gotchas?


And just to try and swerve mildly back on topic... The StopTech kit is, surprisingly, worth the money. At least in my install, the kit arrived as intended - all parts intact. Instructions matching the actual process needed to arrive at functioning brakes and all. The calipers and rotors appear to be very well made, and all parts fit together perfectly. The stand-off used to move the caliper to match the new rotors was very well finished, and, well, it does just plain work. IMO, I wouldn't mark the exterior of the boxes quite so obviously - I'd be afraid you lose a few to ones that 'fell of the truck' simply because people can tell what they are...

One question though. The kit includes a little packet of locktite, but I didn't see anywhere in the instructions where to apply it. Only thing I can think of is 1) the stand-off, where the oem caliper bolts hold it, or 2) the 'jet nuts' used to hold the caliper to the stand-off. I checked the bolts and nuts after the first day of the event, and everything seemed tight, then again when I got home and swapped on the street tires/wheels. Again, all A-OK. Where is it supposed to go?

ahm

 

ahm,
Thanks for the kind words on the kit. It sounds like you are pleasantly surprised by the kit. It also sounds like you have had a few "not-so-bolt-on" bolt-on's in the past.
I'm proud to say that we really do ship a complete kit. If you follow the directions, you can't really mess it up. We try to leave as little as possible to chance.

As for loctite...there's only one place you should put it on. The factory bolts that hold the caliper bracket to the spindle...that's it. Even there, if you torqued those bolts properly on the install, I wouldn't go through the trouble of taking it back apart to put loctite on there. You will be fine as long as they are torqued down to spec. Enjoy the kit, and let us know if you need anything else.

 

A couple things here I can speak to. The only track compound that I've personally tried with the Stoptechs is the Carbotech Panther XP8 (I think it might be Jason you're thinking of that has tried several others.) The Carbotechs are OK (they've never faded on me and have worn well after about 6 track days,) but the fitment isn't perfect and they deposit like crazy on the rotors.

Once I get a little more wear out of the Carbotechs I'll be trying the Cobalt Friction Spec-VR compound. Like others here have said...they seem to make a good product and they really take care of their customers (and they also give a 10% my350z.com discount, although most other vendors do the same.)

Also, I've heard nothing but good things about the Performance Friction pads, but at >$250 a set, I think I'll try the less-expensive Spec-VR first.

As for install tips on the PS cooler, I had my trusty local Nissan tech-guru (who's also a member on this board) do the install. Anything that carries fluid (that's fancier than a brakeline) is an install that I'll happily leave to the pros. The install process for the Nismo piece basically requires removing the front bumper and drilling 2 new holes in the mounting piece to accomodate the longer cooling tube. So if you feel comfortable drilling into your car (I believe that the cooler comes with a template) and replacing your power steering fluid, you should be okay. But for me, paying for the hour of labor was well worth it to not have to worry about this stuff.

One other thought I had about why some people have PS fluid problems and some not might be the wheels. I use the stock (and heavy) 17s and have had PS fluid problems, but several others use lighter wheels and have not had problems, after as many (or more) track sessions. It stands to reason that heavier wheels could stress the steering system more, and thus cause more problems sooner.

I hope this was moderately helpful.

Gary

 

That's strange. I went to cobaltfriction.com, and couldn't find the recommended pad application for the ST40 calipers. What's up with that? I read somewhere that some previous generation Porsche 911 pads would fit the bill, but I'm not sure.

BTW, how does one know if he's having PS fluid problems? Does it feel like the front tires hop while turning, or is it the absence of steering while turning the steering wheel?

 

Q1- Yes, the ST40 pad is the same as the 993 turbo (and several other models') pad. At least, I think that's it. Someone, maybe J Ritt can comment.

Q2- The most obvious sign is seeing fluid seeping out of your power steering fluid reservoir under the hood. Mine is coated in caked-on gunk from overflowing when I stay out on track too long.

 

I did not know that. Regardless, I spoke to Cobalt today, and they do in fact have an VR application for the ST40 caliper; it's listed at $209.

hehe, same here.

 

Yes...pad shape on the ST-40 is the same as a 993 911.

We do sell a Spec-VR compound for our caliper. Our part number is 63-300-0372. Retail is $189 from our website. I'm not sure what the Cobalt part # is.

 

Keeping this as far removed as possible from the original question..... .......per Q2, I've seen most Z's that are tracked spill brake fluid out of the reservoir. I never have. And I don't know why I don't. This year I drew about a 1/2" of fluid from the reservoir, leaving it about 1/4" below the "full" line, with narry a drop of spillage! I'd guess R compound tires MIGHT be a cause, but I've seen Z's with RO40's leak fluid.

 

I'll toss in my two cents here.

I have a Track with the stock Brembos and SS brake lines. I've run 35 track days at seven tracks since getting the car two years ago.

After using up the stock pads, I moved up to Ferodo DS2500, then to Panther Plus.

Based on John's recommendation, I put in a set of Cobalt Spec VR pads before going to Lime Rock last month. I think the world of John, but I'm not all that impressed with the Cobalts. For my money, they don't perform any better than the Panther Pluses and they squeal and dust like crazy. It was painful driving to and from Connecticut with them, having to apologize to every toll booth attendant!

I'm also rather disappointed with the DBA one-piece rotors I put on the fronts in July. I've only done seven track days and 600 track miles on them, several of them fairly light instruction days at Summit Point, and already I'm getting faint hairline cracks. It took about 20 track days and 2,000 track miles to get to this point with the stock rotors! I was thinking that at $460 the DBAs were a pretty good deal, but maybe not.

Also, I noticed when I changed the pads last month that the calipers are definitely in need of a rebuild. Has anyone here done this yourself? I'm inclined to let a mechanic handle it, since I don't have a garage and we're into cold weather. But I'm willing to listen to anyone who wants to persuade me to do it myself. What do you think?

 

Hey commasense - get EZPass! That way you won't have to apologize to the tollbooth guys!

In all seriousness, pads are such black magic. Some pads that work great for one person in a Z running 1:01s at Lime Rock will for some reason not work at all for someone else in the same car running 2 seconds slower. It's strange. That's why you have to experiment and once you find something that works, you're probably better off not switching.

 

I'm suprised no has mentioned porterfield R4's for track use. I know there are newer pads out there, but for me they're a great blend of rotor friendliness and heat capacity. I've been using them for years and never had any problems with them. I also have the stoptech 13" front kit and use the R4 pads front and rear. They do sound like a school bus but I've never been inclined to apologize to the toll booth collector .

I am an instructor / advanced driver and have run many sessions with the stoptech's and am very pleased with them. The tracks out here are not very brake intensive (except for Laguna). For some reason I have never experienced any knockback although I've been in other 350's that had it.

 

Sorry they didn't work out for you James. While I'm confident you did, were they bedded in correctly? You're right that they dust a lot and they like to squeal, but that doesn't bother me too much.

Very true.

As is Jason Bourne, Commasense, and myself.

 

Jason, do the pf01's have a corrosive dust? I've used the pf97's and while they have excellent bite and last a long time, I don't use them anymore because the dust instantly rusts and bonds to my wheels and paint.

 

daveh -

I used to run the R4 in my BMW but when I went to Hoosiers they started cooking too fast. That car didn't have great brake cooling and they would only last a day or so if I drove the car a lot (for example if I had two drivers). So I switched to other pads after that. They certainly have a mixed reputation out there although I personally think they're a decent pad. I think the R4S has hurt the R4's reputation.

My sense on the PF01s is that the dust isn't that bad but to be honest I haven't really paid much attention. I keep my track wheels in big garbage bags and I haven't cleaned them since I got them - so while I think they look OK under the dust, I can't be 100% sure. They serve a function and I don't get too worried about how they look. I haven't had any problems on my car's paint that I've noticed (but my car is "silverstone" - which I think means "Brake dust color" in Japanese).

 

Gotta love this line:

"I haven't had any problems on my car's paint that I've noticed (but my car is "silverstone" - which I think means "Brake dust color" in Japanese)."

I'll add that what Jason said about different results for DIFFERENT drivers rings very true......Stick with what works.....for YOU!

I've also instructed........but I'm definately NOT an instructor, so....what does that make me?...........Strange?