HSVMX5

Just wondering what type of brakes other people are running, and how they have found them for track work.

I have a Goodwin 6pot big brake kit on my car and having problems with them. I have gone through about 4 sets of pads on the front, and a set of rotors and have only done 6 track days. At the moment, I have put on a set of rotors from 949Racing, along with carbontech pads. I have been running the standard NA booster and BMC, and have put on a set of NB2.5sport brakes on the rear.

In the process of changing the BMC and booster from the NA to the NB2.5Sport setup in the hopes of giving a better pedal action on the track (or maybe even just trying the 2.5BMC with the NA booster).

About to run cooling ducting to the brakes as well, rotor size is 280mm front and rear.

Problem has been heat build up, the brakes last about 6 laps and then are pretty much toast. I would have thought with the brake setup that I had put in, being still a pretty light car (1150kg) even with the V8, would have been more than enough, but I seem to be chasing my tail on this one all the time.

MRM331

I have the following:

Front:
Wilwood 4-pots over 1991 VW Corrado rotors (280mm). Stainless braided lines.
Rear:
Stock 1994 Miata rotors and calipers (250mm). Stainless braided lines
Master:
Stock 1994 Miata
Prop Valve:
Stock 1994 ABS

Pads:
Originally I used Wilwood's BP-10 smart pads on the front and Axxis Ultimates on the rear. The smart pads would wear down so fast that I'd need to have two sets on hand for a track day. They were so metallic on the street that I started using Hawk HPS on the front when not on the track with the same Axxis ultimate rears. Again, the car was at times scary.
I though all issues had to do with my front/rear bias so I purchased a adjustable prop valve from Flyin Miata. Due to isues beyond my control I didn't get a chance to install it before the next track day but did switch up my pads. I went with a full set of Hawk blues for the track and replaced my rears with Hawk HPS so they would match the fronts on the street.
With matched pads front and rear the car was completely different on both the track and the street. It brakes so awesomely now that I never even put the FM prop valve on.

-Jason

charchri4

I can’t speak directly to Miatas but I can speak to burning up numerous sets of pads, fried wheel bearings and boiled brake fluid at track days. On the tanks I have run (Mustangs and Camaros) dissipating heat buildup is by far the most critical need to brake function. My favorite street / track pad by a long shot is HPS pads. I really don’t think they have more stopping power then a cheapo NAPA pad but hot or cold they feel wonderful to drive and last for multiple track days. For rotors I have found the less bling the better. Good old heavy duty blanks by Best Brakes or some other US made rotor outperform all the slots and holes in the China junk any day.

For brake cooling the best set up I have found – hang on this is really bogus – is an old electric air pump motor plumbed through heater hose to the brakes. The reason it works so well is it dumps a ton of air to the rotors all the time. So even on a 45 mph cool down lap or rolling in the pits you get lots of air movement. I’m sure there are better solutions but I have exactly ZERO dollars invested into my current set up so it’s pretty workable for me.

Thus far my LS1 Miata build plan calls for stock rotors, Hawk HPS pads, no abs and my bogus air pump. I know that will be plenty for autox and probably close for track days but we’ll see.

DIY Brake Ducts for less then 20 bucks - LS1TECH

MRM331

That is by far the most interesting use of a piece of smog equipment I have ever seen. When I first read your post I though you ment the temporary air pump included in many cars to pump the tires in an emergency. That would be ghetto.

A Mustang 5.0 originally had a belt driven smog pump that sent air to the cats and heads via heater hose. This sort of makes me want to bolt the thing back up and do this with it...

-Jason

charchri4

LOL! Yeah the minute I posted that the price on LS1 electric air pumps doubled! I heard back from a guy in Las Vegas that tried it and he was equally amazed at how well it works. It's just a little hard to tell anyone about it with a straight face cuz it's a little...

HSVMX5

Sounds like a bit of a plan, but I wouldn't have a clue where to source one of those down here, nothing that I know off came out with an air pump?

What were they from in the States, and how big are they, just wondering about what it would cost for international shipping

charchri4

Oh that's easy. Just go to a “you pull it” salvage yard and start looking under hoods of cars with larger engines in them. Follow the 1" black hose from the exhaust manifold and if it doesn’t go to a belt driven pump on the engine you've found one. Most of them are tucked under an inner fender well or somewhere out of the way so you may have to hunt a little.

I just jumped on ebay and searched on electric emissions pump, electric smog pump, electric A.I.R. pump etc all with the "used" button checked and had a ton if hits. There are a million of them out there from all different makes and models.

For what it's worth mine is from a 2002 LS1 Camaro and it moves a truck load of air. I found one exactly like it for $31 plus $10 in shipping on ebay just now.



To give you an idea of the size the smaller port is about 5/8" and the larger one is about 7/8". I would imagine most any of them of that vintage and that size engine would be about as powerful.

One thing to note thus far I have had no trouble with mine running for an hour + at a time even with the air temp at 100 deg F on the track. But in their normal intended use these pumps only run for a few minutes on cold start. I would imagine mine being where it is with tons of air blowing over and through it helps with the longevity of it.

Also my apologies I did not intend to highjack this thread with all this pump nonsense...

MRM331

That's alright, I completely forgot waht this thread was actually about...

If I experence any brake fade at the track this year I am 100% going after this idea.

-Jason

HSVMX5

That's ok, didn't think it was hijacking, I did ask for what brake setup people ran, rather than brakes, and venting is as much a part of the brake setup as anything.

Started the thread to get ideas of how to fix my issues that I am having on the track and what other peoples experiences have been on track days with their V8 powered MX5 (sorry, Miata's for everyone else that doesn't come from NZ)

amaharaj

Has anyone used the brake venting setup from Flyin' Miata?

charchri4

Well now I learned another new and wonderful thing on this forum! I never looked at the brakes page on FM before and they have some very cool stuff. The vent plates look nice but easy to make for 0 to 5 bucks.

But I have a question for you guys. They list a grossly overpriced proportioning valve on the brakes page and talk about limiting the front brakes with it. Front brakes - really?? That is totally opposite world for any brake set up I have ever done. I have used that same valve they list several times (purchased for half that price). But I have always put it in the back to prevent wheel hop and allow for more aggressive trail braking without the back end stepping out.



Do you guys have any experience with what they are saying about using these valves on V8 Miatas - in the front brakes?

MRM331

As far as I know you put it on the back brakes to give them more pressure. I guess since you're giving more pressure to the rear you are sort of limiting the front.

Miata brakes are traditionally heavily weighted to the front.

The valve is a little overpriced. It's the same valve you pick up on Summit's site for half the price. What sort of justifies their price are the three fittings, two metric to standard adapters and a metric brake union. I've tried to find the fittings and while you can find them for less they will not look as nice and you'll have to find them first. The other option is to get the cheap valve and reflare your lines to match the fittings that come with it...that's a bit beyond the market FM is shooting for.

-Jason

charchri4

I think you are backwards on that Jason. Correct me if I am wrong but I believe the valve can't add pressure, it can only limit it or turn it down.

If you think about how it works, it's really just like a faucet on a garden hose. The valve itself has no pump or booster for it to add pressure to the system. So by putting it in the back you would reduce pressure to the rear and bias the braking power forward for more front brakes. That is the way it is done on every track car I have ever heard of but sounds like that is not the way to go with Miatas.

Good point on the turnkey set up with the fittings from FM. Those little buggers are expensive!

MRM331

Sorry, as an English teacher I'm not proud of my inability to express what I was trying to communicate on that last post...I'll try again:

What I meant to say is that the adjustable valve is used to replace the stock proportioning valve. The stock valve sends very little bias to the rear so replacing it with the adjustable valve increases the available bias one can send back there. Most run the valve full open I hear which I believe sends half the pressure to the rear as the fronts receive with just a brake union in line.

Again, from what I hear, the most "balanced" stock proportioning valve is the 1994-95 ABS valve, which is what I have. This is probably why my car is fine with just matched set of pads. I may still try the adjustable valve when I next have a reason to open up my brake system (bleeding an ABS booster is a pain).

Does that make more sense?

-Jason

charchri4

English teacher!!! Oh lord I hope you don't read my blog - LOL... My was a HS English teacher for 38 years so yeah I know... :-) I also know you are in a thankless politically charged position and my hat goes off to you for what you do and making it great. You will never know the difference you truly make in your students’ lives. Or is that Student's ...

Yes that fills in a very important detail. I did not realize the thought was to remove the factory valve but with that idea putting it in the rear makes perfect sense. I’m not really sure this valve is meant to actually replace the factory valve which is probably why FM is putting it in the front and leaving the factory valve in place.

I see a need for much more research and input from experienced track guys on the subject!

HSVMX5

I have found the opposite, that my rear brakes were tending to lock up before the fronts on the track, this was running the standard BMC and valve with the 1.6 calipers on the rear and the 6pots on the front. My suspension setup hasn't been the best, and think it could have been more to do with the weight balance being a bit further forward on the V8 than the standard car along with the transfer under braking making the rear end go light. I have since replaced the rear 1.6 calipers with the larger 1.8 NB sport brakes along with BMC and valve and will see how that goes, whether it helps things out. I can say one thing for sure since changing the BMC, the pedal stroke is way shorter than before, but I do need to check to make sure there is no drag on the brakes and adjust if there is, as I only need to barely touch the pedal and can feel the brakes engage.

corndogs

Im running 13" 2 piece rotors with Magnesium Alcoa Calipers on the front