300mm Big Brake kit vs 276mm Micro Big Brake kit with 15inch Watanabe's?

Suspension, including wheel, tire and brake.
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B^2
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300mm Big Brake kit vs 276mm Micro Big Brake kit with 15inch Watanabe's?

Post by B^2 »

I'm in the process of doing a couple upgrades on the suspension of the 510 and I'm looking for some guidance regarding brakes. So far I've ordered the rear coilovers and the front weld on kit for the 280zx struts. Right now for an engine I'm running an L20b with dual Mikuni 40's but at some point in the future I may upgrade to a Ka. I've heard some people say the 300mm rotors that could with the big brake kit won't fit the watanbe's I have which are 15x6.5 while some people say it's very tight. You can see my wheels here:https://www.instagram.com/p/Bjcx_vtgBYt/

My questions are:

1) Will I notice a big difference in performance between the two rotor sizes if I'm just casually driving the car with some canyon cruising? Eventually, I'd like to try autox and swap in a more powerful engine but not if 300 vs 276mm for rotor size is splitting hairs for my application.

2) Should I be looking somewhere else besides t3 for a front brake kit on 280zx struts?

3) Should I just get new 280zx pads, rotors, and calipers and call it a day? I figured the cost for all that stuff isn't too far off from buying new/more modern stuff.


Please let me know if there is something else I should be thinking about.
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okayfine
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Re: 300mm Big Brake kit vs 276mm Micro Big Brake kit with 15inch Watanabe's?

Post by okayfine »

1. No, you won't notice given the driving you describe, even with the KA. Stock ZX brakes were enough to stop a much heavier car. You could gain some braking performance just with pad selection (go-to used to be Porterfield pads). I had 11" rotors (stock Z31) and in similar driving the first brake application was not confidence inspiring - the big rotors needed some heat in them to really help the pads bite.

3. Hard to find new ZX calipers, or used to be a few years ago. Can't imagine that's gotten better.
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B^2
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Re: 300mm Big Brake kit vs 276mm Micro Big Brake kit with 15inch Watanabe's?

Post by B^2 »

One of the other things I've been told is that the unsprung weight of the 280zx stock setup is higher than what it would be for a wilwood replacement which seems like an incentive to upgrade. It's also my understanding that the 280zx brakes are single piston vs wilwood being a 4 piston which should increase stopping power. This also seems to be one of those situations where bigger isn't better when it comes to rotor size.
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bertvorgon
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Re: 300mm Big Brake kit vs 276mm Micro Big Brake kit with 15inch Watanabe's?

Post by bertvorgon »

If you are not racing...it really is not a big deal!

Okay is right, unless you are truly racing, you do not need BIG brakes, as even the larger rotor increases the weight.

Larger rotors means it takes awhile and some serious heat to get things working, and again, unless you are racing, the smaller package is just fine on our LIGHT 510's. I have road raced mine, on one of the worst tracks for brake cooling, and do that no problem with my ZX rotor.

Same with Solo and Canyon carving...hell...I hardly ever use my brakes in the real world driving.

Again, pad choice is the big deal, and, use good brake fluid, THAT will get you more performance. I picked the softest pad I could use in my setup for ALL but real track days!
"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan

Keith Law
1973 2Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1968 Vintage 3HP Mini Bike
1971 Vintage 13' BOLER trailer
B^2
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Re: 300mm Big Brake kit vs 276mm Micro Big Brake kit with 15inch Watanabe's?

Post by B^2 »

bertvorgon wrote: 19 Aug 2020 12:27 If you are not racing...it really is not a big deal!

Okay is right, unless you are truly racing, you do not need BIG brakes, as even the larger rotor increases the weight.

Larger rotors means it takes awhile and some serious heat to get things working, and again, unless you are racing, the smaller package is just fine on our LIGHT 510's. I have road raced mine, on one of the worst tracks for brake cooling, and do that no problem with my ZX rotor.

Same with Solo and Canyon carving...hell...I hardly ever use my brakes in the real world driving.

Again, pad choice is the big deal, and, use good brake fluid, THAT will get you more performance. I picked the softest pad I could use in my setup for ALL but real track days!
what brand of pads do you use/recommend? What about rotors? Learning towards just staying with the stock 280zx setup but replacing the pads and rotors.
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bertvorgon
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Re: 300mm Big Brake kit vs 276mm Micro Big Brake kit with 15inch Watanabe's?

Post by bertvorgon »

I use the "stock" 280zx rotor, not sure what brand they were as it has been a long time since I changed out rotors. As I hardly use my brakes, everything seems to last a long, long time on my car.

Pads...others can chime in, as I bought BRAKEMAN pads, for my BRAKEMAN calipers, basically the same size as the 280ZX caliper, but 4 piston.

I asked them for the softest pad they could supply for my street and canyon carving driving. If I solo'd I would use these pads.

I think Porterfield's are what get talked about a lot here, for street and some combat use.
"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan

Keith Law
1973 2Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1968 Vintage 3HP Mini Bike
1971 Vintage 13' BOLER trailer
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bertvorgon
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Re: 300mm Big Brake kit vs 276mm Micro Big Brake kit with 15inch Watanabe's?

Post by bertvorgon »

This is my setup with the after market caliper and stock rotors.
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"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan

Keith Law
1973 2Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1968 Vintage 3HP Mini Bike
1971 Vintage 13' BOLER trailer
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