12:05 Garage- ’70 Duster build

[racerjoe]

RockAuto used to be a gold mine for info like this. But at some point things changed and now it is much more difficult to find the pertinent info. Seems like Raybestos is one that gives some info though.

Looks like the 2012 GT rotor is 1.89" in overall depth. More Information for RAYBESTOS 680811R

Maybe the 2015+ Brembo equipped Mustang rotor? More Information for RAYBESTOS 681954R

That gives you about .6" more clearance, but they are 15" rotors. No idea if you could fit an 18" wheel over that, but kind of doubt it. I know the Mustang guys have threads about mounting 18" winter wheels on cars with the Brembo brakes, but doesn't seem possible to me. I guess you could see how much room you have in your rim though.

Might look at the 4 piston Brembo rotor from a Challenger. More Information for RAYBESTOS 780690R

Those are 14.2" in diameter but only give you about 3/8" more clearance to your wheel spokes.

How about a front rotor off an 2010 MB S550? More Information for RAYBESTOS 980743R

Only 13.8" in diameter, but better than 5/8" more clearance to the front of your wheel. But will probably take a machining step to clear the wheel studs and hub.

Not sure how much clearance you need to get your calipers to clear.

Keep us posted.

I thought the modern dodges were 115mm bolt pattern. It wasn't until you mentioned it that I took another look and it seems like they switched from 114.3 to 115 in 2013. Its looking like the Challenger RT rotor may work, or at least be very close to working. It is slightly larger at 13.6" vs. the 13.25", but I seriously doubt that will have a big impact. I'm going to go grab a rotor from the local parts store to see if it will work.

 

[mygasser]

can't you turn the back of the hub flat to suit and mount the disc you have from the back instead of the front? same result as buying deeper discs and you've got access to the lathe so worth trying before buying more parts.
neil.

 

[DionR]

I thought the modern dodges were 115mm bolt pattern. It wasn't until you mentioned it that I took another look and it seems like they switched from 114.3 to 115 in 2013. Its looking like the Challenger RT rotor may work, or at least be very close to working. It is slightly larger at 13.6" vs. the 13.25", but I seriously doubt that will have a big impact. I'm going to go grab a rotor from the local parts store to see if it will work.

There has been a huge disagreement on what the bolt pattern is on the LX/LC cars. I've found info on RockAuto showing the bolt pattern for the earliest cars at 5x4.5", and even measured a steel wheel myself and found the same. Yet most of the published data shows 5x115. I finally gave up and couldn't tell you what the real number is.

Regardless, I wouldn't worry about it unless you were looking at running LX/LC wheels. The brake rotor just needs to slide over the studs and be flush with the face of the hub. Beyond that it really doesn't matter.

Be aware that the 13.6" rotor is not as deep as the 14.2" rotor I linked. It is only 2.15" tall overall and will only give you an additional 1/4" of clearance compared to the Mustang rotor.

 

[DionR]

can't you turn the back of the hub flat to suit and mount the disc you have from the back instead of the front? same result as buying deeper discs and you've got access to the lathe so worth trying before buying more parts.
neil.

I wouldn't just for 2 reasons.

1. That would lose the structural bracing that the HD rotors came with. I like those and wouldn't want to give them up.

2. Any brake job after the first would require removing the hub to get the rotor off. I had a Honda that needed that and instead of new rotors it got new pads and grooved rotors because I had neither the time, nor the money to do it right.

Unless it came down to a horrible alternative, then wouldn't put the rotor on the inside of the hub. Just me though.

 

[mygasser]

I wouldn't just for 2 reasons.

1. That would lose the structural bracing that the HD rotors came with. I like those and wouldn't want to give them up.

2. Any brake job after the first would require removing the hub to get the rotor off. I had a Honda that needed that and instead of new rotors it got new pads and grooved rotors because I had neither the time, nor the money to do it right.

Unless it came down to a horrible alternative, then wouldn't put the rotor on the inside of the hub. Just me though.

fair enough, just thought i'd mention it as a possibility.

 

[DionR]

fair enough, just thought i'd mention it as a possibility.

Good point. It's a valid idea and would potentially solve some issues. Didn't mean to sound like I thought I was knocking it, only meant to share my thoughts on the drawbacks.

 

[racerjoe]

I picked up a 2010 challenger rotor from the local auto parts store. This rotor is 13.6” where the mustang rotor was 13.2”. The offset of the brake surface is slightly less than 1/4” further back than the mustang rotor. It fits, but it’s close. A 1/4” wheel spacer will cure all the problems and won’t cause any tire rubbing. I guess if I had used a modern style wheel none of this would have been a problem. New wheels isn’t an option.
The bracket probably can’t get any easier to make either. I made one out of hardwood as a test piece-that’s what is holding the caliper on in this photo.

 

[DionR]

I picked up a 2010 challenger rotor from the local auto parts store. This rotor is 13.6” where the mustang rotor was 13.2”. The offset of the brake surface is slightly less than 1/4” further back than the mustang rotor. It fits, but it’s close. A 1/4” wheel spacer will cure all the problems and won’t cause any tire rubbing. I guess if I had used a modern style wheel none of this would have been a problem. New wheels isn’t an option.
The bracket probably can’t get any easier to make either. I made one out of hardwood as a test piece-that’s what is holding the caliper on in this photo.


View attachment 1715686569

Any pictures from the back?

Glad that the additional thickness from the rotor and the 1/4" spacer doesn't cause the tire to rub.

Nice job!

 

[racerjoe]

Any pictures from the back?

Glad that the additional thickness from the rotor and the 1/4" spacer doesn't cause the tire to rub.

Nice job!

I need to make another one to bring the caliper down 1/8”. That was a dimension that was rather hard to get. I got it close (within an 1/8”). It will need 1/4”-3/16 space on the front side of the bracket. That will have to be fine tuned once I have steel brackets since the wood collapses when I tighten the bolts. I’ll be happy to share my drawing when I’m done for anyone that wants to replicate this pile of parts I’m calling a brake system.

 

[DionR]

I need to make another one to bring the rotor down 1/8”. That was a dimension that was rather hard to get. I got it close (with an 1/8”). It will need 1/4”-3/16 space on the front side of the bracket. That will have to be fine tuned once I have steel brackets since the wood collapses when I tighten the bolts. I’ll be happy to share my drawing when I’m done for anyone that wants to replicate this pile of parts I’m calling a brake system.

View attachment 1715687196 View attachment 1715687197

Mine ended up on the other side of the spindle:

But I am using a flatter Cobra rotor and floating calipers. Note that was a wood test piece as well, I just painted it black to get the feel of it.

I had a rough time getting the pads on the rotor correctly. My initial CAD layout had the holes in the spindle off and I got to the point where I had brackets cut and everything before I realized it. Revised my layout, had another set cut and (I think) I nailed it the second time.

In the end I am mostly pleased, but both sets of calipers I have put on the car have been spread so the outer brake pad isn't making full contact. I am planning to try a late model Challenger caliper later this year and see if I have better luck.

I would prefer fixed calipers like you are using but I don't expect to make that jump anytime soon. And the calipers you have are getting expensive, last I checked. There is a set of brackets for sale on this forum right now to use the same calipers with an MB rotor but the hub is custom and I don't know where someone would get a set. But it got me to looking for the early Viper calipers which is when I discovered they aren't something I want to buy right now.

 

[racerjoe]

Mine ended up on the other side of the spindle:

View attachment 1715687228

But I am using a flatter Cobra rotor and floating calipers. Note that was a wood test piece as well, I just painted it black to get the feel of it.

I had a rough time getting the pads on the rotor correctly. My initial CAD layout had the holes in the spindle off and I got to the point where I had brackets cut and everything before I realized it. Revised my layout, had another set cut and (I think) I nailed it the second time.

View attachment 1715687227

In the end I am mostly pleased, but both sets of calipers I have put on the car have been spread so the outer brake pad isn't making full contact. I am planning to try a late model Challenger caliper later this year and see if I have better luck.

I would prefer fixed calipers like you are using but I don't expect to make that jump anytime soon. And the calipers you have are getting expensive, last I checked. There is a set of brackets for sale on this forum right now to use the same calipers with an MB rotor but the hub is custom and I don't know where someone would get a set. But it got me to looking for the early Viper calipers which is when I discovered they aren't something I want to buy right now.

I had thought about selling these calipers and going with the new Ford Brembo style, but those aren't cheap either, so I decided to keep these and make something work. I got lucky years ago and picked up these for $300 on ebay. I bet it would be hard to find 1 for that price now. I don't know CAD, but have plenty of friends that draw things up for me. I'll just give them a nice hand scaled ahnd drawing with all the dimensions and let them knock it out for me.

 

[DionR]

I had thought about selling these calipers and going with the new Ford Brembo style, but those aren't cheap either, so I decided to keep these and make something work. I got lucky years ago and picked up these for $300 on ebay. I bet it would be hard to find 1 for that price now. I don't know CAD, but have plenty of friends that draw things up for me. I'll just give them a nice hand scaled ahnd drawing with all the dimensions and let them knock it out for me.

I think the cheap way to go today is the Scat Pack calipers or maybe something from a GM car. Not really sure about the SP caliper though as they have a different construction than the Viper calipers you have, but they seem to run them on a lot of cars.

I have a single radial mount rear caliper for a later Viper, but don't want to spend the money for another one and a bracket is much more involved. Everything so far has been easy to get cut out of a plate on a laser or water jet, but that would require buying a kit or getting a machine shop involved.

I started as a drafter and love layouts for this stuff. Unless the base for the layout is wrong (see above).

 

[racerjoe]

I think the cheap way to go today is the Scat Pack calipers or maybe something from a GM car. Not really sure about the SP caliper though as they have a different construction than the Viper calipers you have, but they seem to run them on a lot of cars.

I have a single radial mount rear caliper for a later Viper, but don't want to spend the money for another one and a bracket is much more involved. Everything so far has been easy to get cut out of a plate on a laser or water jet, but that would require buying a kit or getting a machine shop involved.

I started as a drafter and love layouts for this stuff. Unless the base for the layout is wrong (see above).

I'm and EE and CAD drafting wasn't required way back then. Now I'm a dumb salesman....lol, but have plenty of engineer freinds that have access to CAD, inventor, solidworks, etc.

 

[DionR]

I'm and EE and CAD drafting wasn't required way back then. Now I'm a dumb salesman....lol, but have plenty of engineer freinds that have access to CAD, inventor, solidworks, etc.

Yeah, I'm in IT now, but still have access to a couple of CAD programs. Nothing like Inventor or SolidWorks, though. That would be the bomb.

 

[racerjoe]

Puting it all back together to make it driveable and couldn’t help but snap photos of the differences. Holy moly! I hope it brings as much of a braking improvement as it does in appearance!

 

[DionR]

Puting it all back together to make it driveable and couldn’t help but snap photos of the differences. Holy moly! I hope it brings as much of a braking improvement as it does in appearance!


View attachment 1715687466

I like!!

 

[DionR]

I need to make another one to bring the caliper down 1/8”. That was a dimension that was rather hard to get. I got it close (within an 1/8”). It will need 1/4”-3/16 space on the front side of the bracket. That will have to be fine tuned once I have steel brackets since the wood collapses when I tighten the bolts. I’ll be happy to share my drawing when I’m done for anyone that wants to replicate this pile of parts I’m calling a brake system.

View attachment 1715687196 View attachment 1715687197

I wonder how a Scat Pack caliper would compare to those Viper one's dimensionally. Looks like I could get a set of the SP one's for $300 before tax, but that includes the core charge.

 

[racerjoe]

I wonder how a Scat Pack caliper would compare to those Viper one's dimensionally. Looks like I could get a set of the SP one's for $300 before tax, but that includes the core charge.

View attachment 1715687655

The bolt holes are 100mm center to center on the viper caliper. I'd have to do some fancy measuring and math to get the distance from the top of the pad radius to the bolt holes.

 

[DionR]

The bolt holes are 100mm center to center on the viper caliper. I'd have to do some fancy measuring and math to get the distance from the top of the pad radius to the bolt holes.

I did some comparing between them and even if the height was the same, the distance from the back of the rotor to the mounting lugs looks completely different. I think it would take a completely different bracket to make the SP calipers work.

Maybe when I buy my next set of tires I will look at it again. I will probably need different rims to fit fixed calipers and could just swap them all at that point.

 

[racerjoe]

Here’s the drawing. Since I don’t know how precise the laser cutter will be, I had the holes cut smaller than needed so I can drill them to a true 1/2”. I ordered them this morning from sendcutsend.com. They were only $14/ea. And had free shipping. All the local shops had a minimum order so I was forced to use an online resource. Oshcut.com was considerably more expensive per part, setup fee, and charged for shipping.
I guess I need to order all the other parts to get this done. Turning out to be much easier than anticipated.

 

[DionR]

Dang it. I hope you are proud of yourself.

I've spend the last week looking at rotors and calipers. You took me down a rabbit hole I needed to avoid. Like offering an addict a hit!!

Based on RA, the GT500 calipers don't appear to be any more expensive than the Scat Pack ones. Or within $10-20. Thinking hard about buying a caliper and rotor for a GT500 and seeing what it would take. But that means a new set of wheels and tires. The agony of it all!!

 

[racerjoe]

Dang it. I hope you are proud of yourself.

I've spend the last week looking at rotors and calipers. You took me down a rabbit hole I needed to avoid. Like offering an addict a hit!!

Based on RA, the GT500 calipers don't appear to be any more expensive than the Scat Pack ones. Or within $10-20. Thinking hard about buying a caliper and rotor for a GT500 and seeing what it would take. But that means a new set of wheels and tires. The agony of it all!!

lololol!
I have the same disease! Always thinking of car ****. New wheels were not an option for me. Good luck!
Sendcutsend finished my parts on Monday but are being held up by fedex because everywhere is frozen!

 

[DionR]

lololol!
I have the same disease! Always thinking of car ****. New wheels were not an option for me. Good luck!
Sendcutsend finished my parts on Monday but are being held up by fedex because everywhere is frozen!

I was going to like your post, but the fact that your parts are delayed sucks.

Do you think you have enough clearance around the radius to run a 14” rotor in your wheel? In theory, only about .2” closer to the barrel of the wheel?

 

[racerjoe]

I was going to like your post, but the fact that your parts are delayed sucks.

Do you think you have enough clearance around the radius to run a 14” rotor in your wheel? In theory, only about .2” closer to the barrel of the wheel?

I think it would fit but would require a thicker wheel spacer. The problem with my wheels is they aren’t designed for modern cars, they are made for muscle cars. Therefore, the spokes start to curve back instead of staying out toward the face of the wheel. It would be perfectly fine with a rotor/caliper combo that was offset further from the face of the hub. There’s plenty of room to the ID of the wheel. I’m sure a wheel designed for a mustang would work just fine.

 

[DionR]

I think it would fit but would require a thicker wheel spacer. The problem with my wheels is they aren’t designed for modern cars, they are made for muscle cars. Therefore, the spokes start to curve back instead of staying out toward the face of the wheel. It would be perfectly fine with a rotor/caliper combo that was offset further from the face of the hub. There’s plenty of room to the ID of the wheel. I’m sure a wheel designed for a mustang would work just fine.

Just wondering if a 14” Mustang rotor and caliper would fit in an 18” wheel. I know the GT500 verts came with 18” wheels (at least for a year or two), but wondered if I was missing something.

Now that I think of it, the guy in the thread I linked earlier that used GT500 parts had 18” wheels on that car.

Because I set up my hubs for Cobra rotors, it really would only be a new bracket to bolt GT500 rotors and calipers on. Oh, and new wheels. And new tires. And....

Rather use Scat Pack rotors and calipers (I am a Mopar guy), but that setup pushes the adapter bracket to the back side of the spindle. But now that I think of it, that’s how your is. Now I can’t wait to see how yours works and what it looks like from the side.