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downgrade from tii brakes to na brakes for skinny drag wheels

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Old Feb 18, 2011 | 12:48 AM
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downgrade from tii brakes to na brakes for skinny drag wheels

I was curious about doing a downgrade from tii front brakes to na front brakes for skinny drag racing wheels. Few questions.

Will most 15" front drag wheels fit with the smaller NA brake calipers? I know most rims do not fit with tii brake front calipers. I am looking to buy these to match my rear drag wheels http://www.summitracing.com/parts/SUM-521-5465PS/

What parts do I need? I'm only going to do this is i can stay 5 lug. Can I stick with the tii master cylinder? Do I need new brake lines up front?
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Old Feb 18, 2011 | 03:42 AM
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A lot of people use two stock aluminum spares for skinnies, but if you're set on getting those idk if they'd fit or not, however the stock TII wheels are 16x7 and I suspect a 15" wheel would still clear.

You may want a brake distributor valve so you don't overload the fronts while making little use of the rears. Other than that idk what you might need. If I were you I'd just see if the 15's will fit and go from there, if you insist on having THOSE wheels then everything else will have to follow suit to make it work, no?
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Old Feb 18, 2011 | 05:52 AM
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long studs and use a spacer, most people upgrade their brakes not downgrade them
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Old Feb 18, 2011 | 05:59 AM
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Originally Posted by ryans1000
I was curious about doing a downgrade from tii front brakes to na front brakes for skinny drag racing wheels. Few questions.

Will most 15" front drag wheels fit with the smaller NA brake calipers? I know most rims do not fit with tii brake front calipers. I am looking to buy these to match my rear drag wheels http://www.summitracing.com/parts/SUM-521-5465PS/

What parts do I need? I'm only going to do this is i can stay 5 lug. Can I stick with the tii master cylinder? Do I need new brake lines up front?
There's your problem...

The smaller rotors and brakes came on 4 lug cars.
5 lug NA and Turbo S4 cars used the SAME BRAKES.

I suggest you use spare wheels.
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Old Feb 18, 2011 | 06:33 AM
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Originally Posted by Pele

The smaller rotors and brakes came on 4 lug cars.
5 lug NA and Turbo S4 cars used the SAME BRAKES.
My base 5-lug NA (1991) came with single piston front calipers.
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Old Feb 18, 2011 | 10:22 AM
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I'm using the fc spares right now, looking to move away from them so I can have matching rims. with skinnies you don't need strong brakes, the tires are too skinny to provide enough brake traction anyway. I know the rims above in my link as well as most other 15's do not fit with tii brakes.
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Old Feb 18, 2011 | 11:28 AM
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From: https://www2.mazda.com/en/100th/
the gxl/vert/gtu/etc etc all came with the big brakes and 15" wheels...

the 89+ bases came with a single piston front caliper, but its the same rotor as the 4 piston cars
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Old Feb 18, 2011 | 11:58 AM
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Originally Posted by clokker
My base 5-lug NA (1991) came with single piston front calipers.
His signature says that he has an S4.

Also, this:

Originally Posted by j9fd3s
the gxl/vert/gtu/etc etc all came with the big brakes and 15" wheels...

the 89+ bases came with a single piston front caliper, but its the same rotor as the 4 piston cars
Also, I think the S5 base models came with 15" wheels as well.

Options now are:
1.) Redrill 4 lug rotors to 5 lug pattern.
2.) Choose different wheels.
3.) Stick with the FC spare wheels as front skinnies.
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Old Feb 18, 2011 | 01:02 PM
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can the single piston calipers fit onto the tii rotor?
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Old Feb 18, 2011 | 01:09 PM
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I doubt it.
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Old Feb 18, 2011 | 01:43 PM
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Originally Posted by Rob XX 7
long studs and use a spacer, most people upgrade their brakes not downgrade them
+1 to this, easiest way IMO.
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Old Feb 18, 2011 | 02:06 PM
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+2 . i just had to do this to get some ol'skool wheels 15x8, 0 offset . used 8mm spacers clears fine for me
[IMG]http://www.flickr.com/photos/59048198@N07/5456891718/
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Old Feb 18, 2011 | 04:20 PM
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Originally Posted by ryans1000
can the single piston calipers fit onto the tii rotor?
Yes, the front rotors are the same for single and 4-piston calipers.
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Old Feb 18, 2011 | 05:17 PM
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Originally Posted by clokker
Yes, the front rotors are the same for single and 4-piston calipers.
do you mean (S5) front rotors are the same for single and 4 pistons calipers ??
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Old Feb 18, 2011 | 05:29 PM
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Yes.
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Old Feb 18, 2011 | 06:35 PM
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the longer wheel studs and spacers are an option but I haven't looked into their safety at 140+ mph.

so in summary, i can buy s5 single piston front calipers and put them on my 88 tii rotors. so will the single piston caliper itself give me more clearance or is it the single piston caliper along with the smaller rotor that creates the wheel clearance that is needed?
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Old Feb 18, 2011 | 06:43 PM
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From: https://www2.mazda.com/en/100th/
Originally Posted by ryans1000
the longer wheel studs and spacers are an option but I haven't looked into their safety at 140+ mph.

so in summary, i can buy s5 single piston front calipers and put them on my 88 tii rotors. so will the single piston caliper itself give me more clearance or is it the single piston caliper along with the smaller rotor that creates the wheel clearance that is needed?
use ARP wheel studs, we run ARP's and wheel spacers over 1g in the corners, no trouble @all..

you do realize the wheels you linked actually sticks out further than stock, its going to hit the fenders and the brakes look like they are totally clear. the stock wheels have a 5" backspace and the ones you linked at only 1.75....
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Old Feb 18, 2011 | 07:15 PM
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Originally Posted by j9fd3s
you do realize the wheels you linked actually sticks out further than stock, its going to hit the fenders and the brakes look like they are totally clear. the stock wheels have a 5" backspace and the ones you linked at only 1.75....
this rim is only a 4" wide. i guess from my calculation the rim would be 34mm more toware the fender. I read someone on this forum tried this exact rim and the tii caliper rubbed it. guess it would have to do with the shape of the rim design. maybe spacers would not be a good idea with this rim
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Old Feb 18, 2011 | 07:25 PM
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Originally Posted by ryans1000
no i don't think your accounting for that this rim in only a 4" wide rim. it won't hit the fender. also I read someone on this forum tried this exact rim and the tii caliper rubbed it
If it only rubbed then maybe you can just get away with a small spacer. You DO have single piston brake options. So if you get the wheels and find out small spacers wont work, you are not screwed.
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Old Feb 19, 2011 | 12:14 AM
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Originally Posted by clokker
Yes, the front rotors are the same for single and 4-piston calipers.
For '89, base (GTU) cars actually had smaller 9.8" front rotors on the five-lug hubs. (See '89 brochure from the FAQ here: https://www.rx7club.com/showpost.php...27&postcount=6 ) In '90 and '91, Mazda made the 10.9" vented front rotors standard across the board.

Therefore, if rotor diameter is a limiting factor for fitting the wheels the OP is looking at, you'd want to get a set of '89-spec 9.8" front rotors.
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Old Feb 19, 2011 | 08:19 AM
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just look in the drag racing section of this forum, alot of guys are using skinnys with spacers and longer studs
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