Odd Brake Question

[steelvulture]

This may be a bit odd (well, just not the normal type of question), but I was wondering if it would be possible to grind the rotors around the hub (or wherever there's rust where the the brake pads don't) and use a sealant to prevent rust from developing in the future. The sealant shouldn't heavily affect breaking in that braking would get rid of the sealant and any rust that would develop. I've just changed the wheels to the more open G35 6-spoke 17in wheels from my previous Touring wheels on my J30t and I see the rotors more often (sometimes when I look at the wheels and brakes, the rust just stands out and gets on my nerves). Just would like to know if it would be possible to get rid of the rust, prevent it from developing in the future, and not alter the rotors too dramatically. Thanks.

[Jeff Williams]

I bought the "metal finish" spray paint from Wal-Mart. Then I scrubbed the rust off, and cleaned the rotors, and painted the hub part. I also cleaned all the brake dust off the hoses, and calipers. I used a brighter silver paint on the calipers, to emmulate aluminum. I then used Windex on the hoses, and they looked like new. Then I noticed hte struts ,upper links, springs, and everything else. The cleaning and paint looks good for a while, but brake dust forms, and it looks prety much how it did before.

[Q45tech]

IRON RUSTS and the brake compound MUST transfer a thin film to the rotors for the system to work........why it takes 100-250 miles after a rotor replacement or trueing for the brakes to work correctly.

The coefficient of friction for polished iron rotors [without the brake pad compound layer] is about half what it is when the layer forms.

[steelvulture]

Well, I wasn't thinking about using sealant where the pads would make contact with the rotors. I just said about the pads rubbing any sealant off in case sealant would end up getting on these areas during the process. I was thinking about the hub and where rust develops (to the point when it is easily visible - dark red) because the pads don't make any contact. I just want to do something similar to what Jeff did when he had painted the hubs of the rotors. I would just wonder if grinding and a sealant would work because it seems to be more of a long-term solution versus painting the hub.

[j30t]

was thninking about possibly getting those g35 wheels. Do you notice much better performance gain. Right now i have the stock wheels with some cheap sears tires.

[steelvulture]

Considering that I only had them for only a few weeks, I would need some more time to be able to tell a difference. The ride itself does kinda feel difference. Since I got a set of used wheels that came with Bridgestone Potenzas RE92s, I think it has better traction because it is heavier and using better tires (versus older Yokos on lighter aluminum touring wheels). It being heavier would help with traction but just make sure you get good tires. Also, make sure you get the right tire size. The Bridgestones that came on it were 225/50/17s. The size was perfect because it was the widest you can get without having the inner sidewall rubbing against the strut (the strut itself is fairly close to the wheels on the front - the rear is completely clear). The wheels fit fine on the J30's bolt pattern. So if you do get those wheels (G35 6-spoke 17in), just make sure you get good tires to match to get the best performance (and ones that would fit). With my current combination, the performance does feel better and actually handled better in the rain compared to before (old setup spun out a lot). Finally began to rain in Houston so I was able to see how these performed in the rain (no spin outs today - this is really important to me). Hope this helps in making your decision.

[Jeff Williams]

Just a testimony on these tires:

I have had 4 sets of these, and will continue to buy them. They are quiet, handle well, dry or wet, but don't last long, and are expensive. When the tread gets low, they get slippery.

Not the tire I would use, if I was a hard driver.

I have put 2 new sets of these on my wife's I30t, and they last about 30,000 miles.

The 2 sets I had on the Q, were about 50% used, and I got them off of eBay. The handled and rode fine, but the Q was hard on the inner sidewall, on the front. (The negative camber is tough on tires). I now have NITTO NT450's on the Q. A hard tire, that sings abit, but is rock-solid in rain & take corners well. The are alos $50 cheaper, each.

[02q]

I personaly would not buy the Potenza again.I only got 16,000 from them on my mustang gt and about 23,000 on my wifes maxima se,they just don' t last enough.

[steelvulture]

Well, I'm just using the Potenzas because they came with the wheels ($850 for the wheels and Potenzas with only 10k on them and still good tread). I'm just saying that it has better traction than my aged Yokos that I was using previously. I will probably go with other tires that have good tread life and still good wet handling (Potenzas are good in wet but have a treadlife rating of 160). I was thinking about maybe Goodyear Eagle RS-A's when the time comes.

Anyway, does anyone still have any ideas about using sealant around the hub of the rotors? That was what the thread started out as.

[Q45tech]

Ideally one wants to radiate the heat from the calipers and rotors as fast as possible.......either to the air or to the wheels, hubs, bearings to bring down the component temperatures before the brake fluid boils.

Think carefully about paints and coating that look nice, they may insulate the heat from the wheels.And the converse the tire heat needs to flow to the wheels to reduce the internal tire damage..............wide tires may have less surface area exposed to cooling air.........why some 65/60 sizes out perform wider tires that get hotter faster.

[Jeff Williams]

I don't see a problem with sealing the steel. Anything you get on the rotor's brake surface will burn off, the firtst time you brake. The rotors see extreme heat, under braking, so any sealant you use, should be able to handle 200+ degrees.

I say, go for it, and post some pics.

[Q45tech]

Ever wonder why NASCAR still uses 15" tire:15x9.5-in. steel/Goodyear Eagle Racing, 27.5x12-15dNASCAR-approved max. radial sidewall measurement of 13.2 in. at 60 psi......with NitrogenSince 17-18-19-20" tires are so good......all about the blink, blink index.http://popularmechanics.com/au...phtml

[maxnix]

Ever wonder why NASCAR still uses 15" tire:15x9.5-in. steel/Goodyear Eagle Racing, 27.5x12-15dNASCAR-approved max. radial sidewall measurement of 13.2 in. at 60 psi......with NitrogenSince 17-18-19-20" tires are so good......all about the blink, blink index.

Point well taken, but then NASCAR is not about braking and handling. They just go in circles on glass smooth tracks, flat out.

I think Formula 1 is more indicative of the best in tire technology. Even there, you don't see super low profile tires at all. Would love to know about their tire carcass construction technology. But then again, they are all short-lived for light cars going very fast, braking hard, and pulling well over 1G in most bends and corners.

[Jeff Williams]

Quote »Ever wonder why NASCAR still uses 15" tire:[/quote]Actually, the NASCAR tires run between 29 PSI to 35 PSI. It's the "inner wall" donut that has 60 PSI in it. So, when you hear the term "equalize", it means the inner tire has broken its seal, and the two tires have equalized pressure. This is BAD in racing, almost as bad as a flat tire, except it won't send you in the wall, immediately.

Also, there are a lot of reasons that NASCAR has kept its 15" wheels. One is Goodyear, one is $, one is "We've always done it that way", and the last is , a 3,500# car traveling 90 to 140 in the corners, and 180 to 210 down the straights (whick I think, is your point).

[Q45tech]

"The rotors see extreme heat, under braking, so any sealant you use, should be able to handle 200+ degrees."

In test done on Crown Vics [Police Cars] the pads exceed 1170F and the rotor got to 800F some rear pad/rotors combinations were worse than the front.

500-600F is the highest average you will see if you keep the braking speed below 70 mph on single stops buit then again if its 110F ambient plan for 800F.

Brakes can get really hot just like tires can easily exceed 200F when it's 100F ambient, the road can be 120F and the tires 150F just rolling along at speed............camber makes the inner edge 30-40F hotter............easily exceeding the normal design limits........tires are only tested to 100F in the lab in the durability test.........why you get summer tread separation failures.

The extra camber above the 0.83 degrees roasts the tread right off in Summer on the inside!!!!!!!!!!!!!! why you want V/Z rated summer tires that are designed to take extra heat on the compound and are built to assume a little extra camber vs allseason.

Brake pads, rotors, wheels and tires are all an interrelated system.........changing one item will change the heat on the others.

[steelvulture]

Anyone have any ideas of what should be used? So far, I've only seen of Rust-Oleum High Heat which resists up to 1200F and POR-20 which resists up to 1400F. I believe that these only come with color. I haven't seen anything that does the same but is clear. POR-20 comes in "Brilliant Aluminum" while the closest that Rust-Oleum has for High Heat is silver. Any recommendations?

[maxnix]

Cadmium plating on the rotors. High temperature paint for the calipers only.__________________Brian1995 Q45 & Q45t

[szh]

Cadmium plating on the rotors.

Or Zinc plating, too. As done by Irotors.com for their drilled, slotted rotors.

Z