[NoClueGT]

I am looking for a bit of clarity and detail on the "Cressida Big Brake Swap." I've read through the ~25 page post and several others that were easy to find. My eventual use is going to be a bit unique. I have a longer intro post waiting on Mods to approve it that explains the plan to put these parts on a 77GT champcar build

My question is why does this swap require using the Cressida hub? Is it truly needed?
Considering my swap will be unique understanding this will help me as I am sorting through things. From what I can tell my my spindle and mk2 hubs are compatible. I would like to use my stock hub if possible

Because I have not been able to find any pictures of the Surpa mounts on the struts and the Cressida bracket and calipers all mounted together... on the mk2 is this a complete bolt-on, correct? No modification, spacers involved anywhere?

Are there better calipers that with bolt to the Cressida/Supra brackets than the single 2" piston that comes with the Cressida? Champcar is kinda points/cost limited based on the oringal car. My case, the 77

All of this is because I have been digging through long dead 1gen forums and abandoned parts of the internet that imply that mk2 parts should swap back onto 77GT Celica w/o issue. So if it bolts on to a mk2 it might bolt on to the 77



1977 RA23 Celica with 1984 MA61 Supra Brake Swap thanks to the wayback machine

MA61Supra Cressida Swap - Wayback Machine

 

[AJ]

Check out this thread from 2012...

Cressida Big Brake upgrade

I want to do the cressida big brake upgrade like shown here: http://www.tscperformance.com/supra_bigbrake.htm But I ran into a problem. In the article it is stated that I need front brake discs of a 87 or 88 cressida sedan with 272mm diameter. I am searching but I can´t find discs for cressida...

www.celicasupra.com

And a blow by blow removal on the Celica-GTS page

Cressida Big Brake Upgrade

Cressida Big Brake Upgrade

www.celica-gts.com

 

[revvhappy]

I run a MK2 Supra in Champcar and use Celica GTS struts (they give about 0.5 degree more negative camber vs Supra struts), with Nissan 4-piston calipers and Mazda MPV (minivan) rotors. The calipers are truly "bolt-on" but the Mazda rotors need to be re-drilled for a 4-bolt pattern.

 

[NoClueGT]

The MPV rotor is another that I have been looking at as well. That should be the 300zx caliper if I remember correctly.
Revhappy, do you have a build thread I could look at since you are already running Champcar? I might have some questions for you as well go through our build too

Another rotor I have been looking as is the 2006 Mini Cooper S JCW rotor because it is 4x100 11.75" dia x .866" and an overall height of 1.736" (BENDIX PRT5984). But that is if I want to push the limits of what will fit on 15" rim with early non-S boxster calipers. That would be a bit a fabrication on my part to make that all work.

 

[NoClueGT]

Speaking of, currently we are looking at running 15" because that seems to have the widest selection of tire options and shouldn't be too limiting on the brakes.

Right now, my goal is to explore what I can make work from factory bolt-on/mostly bolt-on parts. The stock 77 rotor on this car is not going to last long running champcar. That idea is what got me looking at the Cressida and if I have to use the Cressida hub to make that swap work

 

[revvhappy]

Look in the Racing section for the Lemons MkII build. It's a long read covering 6 years and still upgrading.

The caliper is a 300zx front (Z32). There are a few different options - get the 30mm wide aluminum version. I use the Centric brand MPV rotors which are 28mm thick. It will be incredibly difficult to find a 15" wheel that it fits under and has the correct offset. I tried 15s for a couple of races and didn't like them so went back to 17s. After nearly 20,000 miles of racing and track days I'm still using the original hubs and bearings from the day I built it.

I honestly don't remember why the hub has to be from a Cressida.

 

[NoClueGT]

Thanks Revhappy, I will look for your thread over there.

I bought a new rotor for a Cressida because it was cheap. I'm going to see if it will bolt up to my older hub and take it from there. Maybe I can get luck and only need to modify my caliper bracket to make everything work. I will let you know what I find out

 

[NoClueGT]

Okay, update time...

The bolt pattern of the stock rotor is ever so slightly smaller than that of the Cressida. I've tried to capture that in the pictures. Click thumbnails for the image

The first image shows the rusty stock 77 rotor on top of the Cressida rotor and cropped to show just the bolt hole. You can clearly see how there is just enough differnce between the two to be an issue. I suspect the 77 hub is on a 4x97mm pattern and the Cressida is on a 4x100mm pattern.
Second image, is the Cressida rotor sitting on the stock hub looking down at the bolt pattern.
Third is the 77 hub/Cressida rotor from the side

I have two thoughts on how to address this

1. Slot the holes and make a ring to fit the rotor/hub to make sure I am concentric to the hub​

1.b Turn 90° and redrill to fit the stock Celica hubs. I may still need a ring to be sure I am concentric​

​

2. Find Cressida hubs but not 100% sure it will bolt on to the Celcia spindle​

2.b Supra hub? Better chance it will fit my spindle but will that fix my issues with the Cressida rotor?​

Both seem to be a bit hard to find unfortunately​

​

Thoughts, suggestions on any of these options?​

​

​

​

 

[NoClueGT]

Okay, update time...

The bolt pattern of the stock rotor is ever so slightly smaller than that of the Cressida. I've tried to capture that in the pictures. Click thumbnails for the image

The first image shows the rusty stock 77 rotor on top of the Cressida rotor and cropped to show just the bolt hole. You can clearly see how there is just enough difference between the two to be an issue. I suspect the 77 hub is on a 4x97mm pattern and the Cressida is on a 4x100mm pattern.
Second image, is the Cressida rotor sitting on the stock hub looking down at the bolt pattern.
Third is the 77 hub/Cressida rotor from the side

I have two thoughts on how to address this
1. Slot the holes and make a ring to fit the rotor/hub to make sure I am concentric to the hub
1.b Turn 90° and redrill to fit the stock Celica hubs. I may still need a ring to be sure I am concentric

2. Find Cressida hubs but not 100% sure it will bolt on to the Celcia spindle
2.b Supra hub? Better chance it will fit my spindle but will that fix my issues with the Cressida rotor?
Both seem to be a bit hard to find unfortunately

Thoughts, suggestions on any of these options?

 

[revvhappy]

Can you take a pic of the 77 spindle and post it. Everything on the interwebz says that the 77 Celica has the exact same lug pattern as the Supra/Cressida (4x114.3). Your photos show that they don't match.

A few thoughts considering your intended use of the car (endurance racing). First, I love the idea of racing one but have no idea what the limitations will be in terms of finding reasonable solutions for suspension, power, wheels, etc; or finding what the weak spots of the car will be. In 6 years of racing my Supra it has been an evolution of "breaking things" then finding solutions to make them stronger.

I have no idea how serious or competitive you want your build to be, but here are some things to think about:
1. I would suggest finding a set of 15" wheels to race with. This will give a large variety of tire and brake options. The proper offset and inner barrel size will affect your brake choices.
2. Champcar opened the brake rules this year. You are now allowed to run ANY 4 piston calipers without affecting the budget. I believe that rotors can also be 2-piece with no hit to the budget.
3. Brake parts (including rotors) are consumable items, so think about ease in replacing them. I replace pads and rotors after 2 races (sometimes after one 24-hour race). The "captured" rotors on the OE set-up make rotor changes a pain in the ass - you have to remove the hub and then reinstall it with the correct bearing preload. With external rotors I can replace both front rotors 4 pads in less than 10 minutes.
4. Racing brake pad choice for the Cressida calipers is either very limited or very expensive (my front pads are $240/set and last about 40 hours of racing). In the long run it would probably save you money and effort if you bought a pair of Wilwood 4-piston calipers, find (or have made) adaptors to hold them, and then find a rotor solution that can be easily changed during a race. The same compound pads I use in my Nissan calipers for a Wilwood caliper are $125 a set.
5. As you have found out, finding 40-year-old parts is difficult.

If I had to start again with the new Champ brake rules I would order Wilwood calipers and find larger rotors that fit inside my 17" wheels. Then again, it would probably throw off the front/rear brake bias that is currently perfect with cheap rear brake pads on my Supra.

 

[NoClueGT]

I will try and get you pictures this weekend. I do believe that the lug pattern is 4x114.3. Same as the Cressida and Supra. We had a set of known 4x100 wheels in the garage as our reference and those did not fit.
The 4x97mm and 4x100mm I was referring to are the bolts mounting the rotor to hub. I didn't have calipers with me but I have seen reference to the pattern on the Celica being 97 and took a guess at the Cressida from how close it was.

As a group our goal is to go out, have fun and finish. Where we finish isn't as important and not breaking the car trying.

1. 15's is the plan right now for that very reason. Hearing that from someone else helps confirm we are completely off in thinking that. I am trying to nail down our braking plans currently so we can work on offset
2. That's news to me. I will have to re-read the rules and makes sure I have the current set. I was expecting a 5 point hit because I was planning on going with Wilwood 4 pistons. I also thought that went on the "2x cost" rule compare to stock. So if I was getting hit for 5 points I was going to make the best of that 5 points
3. I haven't really considered how hard it would be to replace the rotors. I was thinking of ease of get a replacement and starting looking for stock Toyota parts. Having it bolt in from the back does make that more challenging
4. After using Wilwood for FSAE I am planning on using their caliper because pad changes are quick and have a wide range of choices in operating temps and friction.
This is the caliper I'm currently considering with the Cressida rotor Powerlite Caliper – Part No: 120-8728 . That puts the overall front piston diameter ~.5" bigger than stock on each caliper so I will probably need to step up the front master as well and include a bias adjuster
5. I am quickly learning how true that is. This old car would look great zipping around the track and the challenge of getting it there is part of the fun

 

[revvhappy]

The Prolite calipers should be great, and I wouldn't change the master cylinder until you test the system. I run cheap auto zone pads on the rear with OE calipers and they last a long time while providing plenty of braking on the "light" end of the car. I have no idea if you intend to keep the drums in the rear or switch to discs. I hear that some brake companies will reline shoes with race compound material. Don't get too aggressive with rear brakes, my car spins very easily with race pads in the rear.

I would match the Wilwood calipers with external rotors - with engineers and fabrication tools you should be able to design radial mounts that will work with larger rotors. You'll need to have the outer edge of the hubs turned down to 143mm to fit inside the rotor hats, but the effort is worth it. Do you know the thickness of rotor that the Prolites can handle? Race pads are usually a bit thicker than street pads.

 

[NoClueGT]

That Prolite I spec-ed to the thickness of the Cressida rotor thinking that using a stock Cressida rotor would be a great place to start. The .86" thick Cressida rotor is widest rotor that works with that caliper because that caliper works with .79” - .86" rotors. Stock for stock curb weights I'm starting at a -700lb advantage from the Cressida. Not sure how long a stock Cressida rotor would last at the track with a 2500lb car but it would be longer than the .49' thick solid rotor from the Celica.

If I went with a thicker rotor, like the 1.1" thick MPV rotor or something else, I would have to work out a new caliper to match. Now would be the time before I buy anything

The rear we had planned to leave stock drums and stock shoes for the moment. No obvious replacement out there for this Celica that would give us rear disks.

 

[revvhappy]

the .86" vented rotors should be fine on a lighter car. Definitely a step up from .5" solid rotors!

 

[NoClueGT]

Here are a couple pics of the stock Celica hub. I really need to buy a cheap set of calipers to measure things because all I could find was this ruler...

 

[revvhappy]

What is the outer diameter of the hub? It looks smaller than the later Supra hubs that I have machined down to clear external rotors.

 

[NoClueGT]

I was trying to work that out today too. I'm estimating ~6.25" diameter until I can measure it with something that would be more accuate

 

[revvhappy]

Hubs need to be shaved to 143mm (5.6") to clear external rotors. In the past I've found a Centric catalog listing the specs of every rotor they make, it might be possible to find an external rotor that bolts on with those calipers.

 

[NoClueGT]

That's great info to know. Thanks

 

[NoClueGT]

Made more progress today. Got a set of Cressida hubs from another member here and I can say that Cressida hubs will 100% bolt up to the 77 Celica spindle. The caliper bracket from the 77 does not work with the stock Cressida caliper unfortunately. But that's okay, I can modify that to work for now. Long term the plan is to jump to wilwood anyway.

One thing that jumped out to me is how much more material there is on the OD of the Cressida part. On the stock Celica it is turned down to allow a smaller rotor to fit.

Now for the good stuff. To make everything work we had to remove the stock heat shield from the caliper bracket because it is now too small. We used the Cressida rear bearing and seals with the Celica front bearing,washer and nuts. One of the other guys has a much new phone than mine and it takes much better photos. We have the Cressida hub and rotor on the 77 spindle. The Cressida caliper is just sitting on the rotor as we will have make some changes for that to work. Because we are getting to where we could be building up our 20R motor soon we are planning on seeing how long the stock parts will last at a local ~1mile long track. It will also give us a chance to see what the car needs before we modify too much more.

With how nice those parts work together we took the time to blast them so we can clean and paint them after we modify the caliper bracket. Plus clean parts weld better anyway