oschool_3

We are doing a short survey to check serious interest in the FB Big Brake Adapter Kits. The last set of these has found their new installs and we are debating about making any more.

Previous inquiries in the Forums and Social Media came back with quite a few people stating that they wanted this kit, but as it turned out, in reality it took more than a year to reclaim the investment. This is just the way things tend to go in the auto aftermarket world.

Looking for suggestions here - perhaps a group buy or other arrangements that will bring the best pricing to our community, but we need to see real commitment prior to making another outlay in time and materials.

Thanks for any input.

gracer7-rx7

iTrader: (16)

Would be awesome if this would work with the earlier (pre 84), smaller spindles...

t_g_farrell

iTrader: (1)

SA big brake kit?

oschool_3

The main reason this kit will only work with the 84’/85’ spindles is that they share the same hub outer wheel bearing as that of the FC. The SA (79’-83’) have a tiny outer wheel bearing. If one is electing to update the brakes on the first gen chassis, it is a relatively small addition to changing the spindles/shock tubes in order to obtain better insert options and bearing capability.

hicks85fb

I would be interested in a kit

LongDuck

Can you tell us a little bit more about what's needed regarding Brake Rotors, which Calipers would fit with your installation kit, and also wheel fitment that you've found works well (16-18")? Also, whether a different brake Master Cylinder and/or Proportioning Valve are required to get adequate fluid flow?

I may be interested after wrestling with brake caliper rebuild recently and ODM calipers are no longer available from Mazda - or any aftermarket place, for that matter.

Thanks!

Sh00bs

iTrader: (8)

what's the price again? i'll be acquiring an fc here shortly for dirt cheap and now have the means to complete this kit.
if it's not toooo much I may be interested.

for everyone complaining about not fitting an SA, well you should upgrade you ish to FB fronts anyway, if not for this kit then for the fact that SA brakes are DANGEROUS and there's a reason they changed them in '81... "it'll hurt value!!!" yeah well your cars value will really be hurt when the crappy sa brakes fail and your car slides off the road. I put '85 fronts on my gf's 79 LE. value aside,, rather her have reliable brakes.

Anywho, just wanted to get my SA brakes are dangerous spiel out real quick.... let us know price and I might get in on a group buy or whatever. Hoping to do a lot of racing this year with my 85!

Carl

iTrader: (2)

You should be able to use this kit on a small bearing strut (no idea about SA) by using a machined stock rotor. MHR650 has a great write-up on this. Our chumpcar team has been doing this for a long time with no failure. You will probably have the change the thickness of the spacers to get things lined up, but should otherwise not be a problem (buy a kit that has not been welded together so that you can make the spacers as thick or thin as you need). Another benefit of using the machined rotor as the hub is that you do not have to use the inner wheel bearing spacer that probably will not come off if you screw up the spindle.

Search on Mhr650 on the site and you will find some really good pictures and write-up.

I have used both techniques special machined bearing spacer (as shown in the pic above) and machined rotor as the hub. I prefer the machined rotor for reasons above, plus you can keep the 4x110 bolt pattern which is convenient if that is what you have in the rear.

After thinking a little more, the machined rotor might get a little funky if you are also using spacer/adapters (to use 4x100 miata wheels) on front and rear like I do on my ITA car, which has now become my endurance car. The ITA car has stock brakes front and rear with cooling ducts in the front. Never had any braking problems sprints or endurance.

I think I am rambling at this point.

Carl

oschool_3

Carl -
Thanks for the input.
I failed to find the Mhr650 write-up you mentioned.
Yes, there are several other options for those who can/do their own engineering and machining work, but we tend to keep a basic approach or offering to the majority of the people who are merely bolting things together.
- Mark

gracer7-rx7

iTrader: (16)

I think Carl is referring to this thread:
https://www.rx7club.com/1st-generati...rakes-1085895/
Or this post:
https://www.rx7club.com/build-thread.../#post11914258

Carl

iTrader: (2)

Mark,

I wasn't trying to bypass what you are offering. I was only suggesting that what you are offering can be used in a variety of situations, with just minor changes by the end user. Your brackets will work even if someone decides to use a machined rotor as the hub.

If someone wants big brakes what you are offering seems to be a good complete package.

This has the general info for mh650. I think there is another write-up somewhere else too that is more detailed. Maybe on the ChumpCar website. Anyway that hub should work with your brackets.

https://www.rx7club.com/1st-generati...rakes-1085895/

(if the link does not work search "mhr650 brakes"

Carl

Carl

iTrader: (2)

Thanks Alberto. That is what I was referring to.

Carl

DWNUNDR

iTrader: (1)

its not a complete package.. you still have to furnish rotors and calipers I believe... that being said.. looks like a good option for us 1st gen guys

KansasCityREPU

iTrader: (9)

I use to have these kits made, via a machine shop, and sell them. One of the issue with the spindle bushings is that if the spindle ever get hurts, you need a new spindle and bushing. I like thes idea of machining the second gen rotor down. This gives more options when a repair is needed.

mhr650

Thanks for the shout out… now I am running the machined rotors plus adapters that let me run 4X100 Miata wheels, good thing since it looks like the 245-40-15 tire wars are heating up. The only thing that is an annoyance is that I never want the bolts holding the spacers on to come loose in a race I end up torqueing them and using red Loctite. I haven’t had to change a rotor yet but I expect it to be a real pain to get the bolts out since it is difficult to get any heat directly on them to break the Loctite.

My new design is using the wheel adapters with lugs added to them so I can bolt Wilwood rotors directly onto the spacers instead of using a normal brake hat. This lets me only have a single part between the wheels and hubs which should improve my wheel runout and save some weight. I have some connections with Wilwood so I can get parts very inexpensively or even free, and having 20mm thick pads in the front calipers is really appealing for endurance racing.

Carl

iTrader: (2)

Once the hub and rotor are removed you should be able to heat the stud from the back side right?

I am using the stock rotor with adapter/spacers, so I have a new set of rotors with adapters already attached set-up for replacement at the track. That does eliminate the quick rotor change without removing the hub, but I can't do that anyway with the stock rotor/hub.

With the stock rotors, I did 19 hours at Texas World Speedway, 14 hours at Willow Springs and 14 hours at Laguna Seca. All the same set of Raybestos ST-43 front pads and $16 rockauto rotors. They (pads and rotors) still are nearly full thickness. TWS and Willow are not huge braking tracks, but Laguna has a couple of hard braking zones. I have Mazda Motorsports cooling ducts, which I know help a lot. We are not driving particularly slowly either since we have placed pretty high in class B (1.9 to 2.4 liter cars). Two 2nds, two 3rds and one 4th (out of 5 total races in this car). The right pads and cooling ducts seem to get the job done pretty well with otherwise stock components.

Once we got the big brakes set-up properly in our other Chumpcar, it has also seen very little brake wear and the performance has been good. Those brakes are essentially the same as the ones initially referenced in this thread.

that_derekjames

Definitely interested in this.

oschool_3

Thanks you all for the great links and most useful information. Your contributions are accepted unreservedly.
As you may understand, the interest and intent for these kits are so diverse that the focus must be limited. If we were a full blown business it may be possible to explore more options or combinations. On the other hand, many inquiries are for one-off applies that are simply not cost effective from our end. It is difficult enough conveying to the average user the various combinations of parts that are a practical apply to a given chassis and duty. Other questions we field are from those that have no track experience and even – little comprehension of the entire brake system, chassis balance or fabrication methods and assembly techniques. Don’t get me wrong, we should encourage the learning process, but some seem to be in far over their heads. These instances give a reluctance to branching out into other alternatives.
Please keep up the good work with your exceptional projects.

Sgt Fox

iTrader: (3)

What price were they before? I think they will become more important as brake parts, especially the GSL rear discs are becoming unavailable.

oschool_3

We have no recollection of what the package cost in the (original) ReSpeed era.
At this time, we are having the machine shops re-quoting costs on another run of parts.
The last batch came in at around $400 per set. The manufacturing has gone up only slightly each time, so we expect the same range or just slightly more.
Expected turn around is approximately three to four weeks, depending on their schedule.

anderdick88

iTrader: (3)

Ill be interested

mikey D

DWNUNDR

iTrader: (1)

DreamInRotary

iTrader: (49)

Yep, these were produced and sold on eBay by the original poster here. I think they eventually sold out and haven't made another batch that I've seen.

I've considered making a new run of similar parts but different brake calipers, due to the rarity and difficulty of finding decent RX-7 front brake calipers. I think RX-8 calipers would be amazing, since they're massive brakes and widely available...

DWNUNDR

iTrader: (1)