bigger rear disc in rear than front a problem I assume?

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I'll have to ask hemi denny, not sure on which kit, just started browsing and kind of surprised at the choices but seems like the only ones with four piston calipers are strange (non vented solid rotors) and wilwood, neither cheap. Seems like some of the wilwood also change track width

Just don't want to play musical wheels or brakes, too costly and I really want to keep the exterior pretty stockish looking
 
newguy said:
I'll have to ask hemi denny, not sure on which kit, just started browsing and kind of surprised at the choices but seems like the only ones with four piston calipers are strange (non vented solid rotors) and wilwood, neither cheap. Seems like some of the wilwood also change track width

Just don't want to play musical wheels or brakes, too costly and I really want to keep the exterior pretty stockish looking
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I think you may have an issue with the cop wheels fitting over the Wilwood hub. The Wilwood hubs are mostly all larger than the ~2.7" center register those cop wheels will have. The Strange brakes are racing stuff, they're not for street cars.

If your car is going to be a street car with a "stockish" appearance, why do you specifically need 4 piston brakes? Number of pistons isn't everything. For example, the boring old single piston Mopar caliper for the 73+ cars, with its 2.75" piston, generates more clamp force than those wilwood calipers do. And certainly more than enough to stop any of the tires you'd be able to run up front on those cop wheels. I ran the later Mopar 11.75" rotors with 2.75" calipers on my Challenger with 275/40/17's up front, those brakes had no problems reeling in those modern compound 275's on that E-body. And that brake set up fits under a 15" wheel too.

Obviously you'd have to run something different with the MII spindles, but there are definitely more brake kits out there for those MII spindles than just Wilwood and Strange.
 
Only reason four piston calipers was a thought was to account for the rear disc being larger 11.2 rotors on the explorer 8.8.

If I could keep the disc brakes that came on the car, I would, but the extra room in the engine bay the hdk gives me is worth swapping brakes, even if I need to go to 17's, but am asking these questions to see if I can keep the cop wheels
 
newguy said:
Only reason four piston calipers was a thought was to account for the rear disc being larger 11.2 rotors on the explorer 8.8.

If I could keep the disc brakes that came on the car, I would, but the extra room in the engine bay the hdk gives me is worth swapping brakes, even if I need to go to 17's, but am asking these questions to see if I can keep the cop wheels
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Yeah again, the number of pistons by itself doesn’t necessarily mean better braking.

Obviously you won’t be able to use the Mopar disks, my point was just that you don’t necessarily need 4 piston brakes with that wheel set up.

And yeah, just because the rear rotor diameter is slightly larger doesn’t mean they’ll have more stopping power either, as it depends on piston size, swept area, etc. And even if the rear did have more stopping power, that’s easily solvable with an adjustable prop valve.

You should definitely get the part numbers on the brake kits you’re considering, Wilwood publishes all their dimensions. And Denny probably knows if any of his customers are running stock Mopar wheels.
 
One kit I'm considering is 140-14271, that hub is listed as 2.76" and I could not get a caliper inside the cop wheel to measure, but measured the hubs on my 74 disc brakes and that measurez 2.8", so it will fit BUT it states it increases the track width .26", so I'll need to mount the wheels again and see if I have that much room to clear inside the fender
 
newguy said:
One kit I'm considering is 140-14271, that hub is listed as 2.76" and I could not get a caliper inside the cop wheel to measure, but measured the hubs on my 74 disc brakes and that measurez 2.8", so it will fit BUT it states it increases the track width .26", so I'll need to mount the wheels again and see if I have that much room to clear inside the fender
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.26 in basically a quarter of an inch, and that's track width so for both wheels... That means one eighth of an inch per side.... If one eighth of an inch causes a issue with tire/wheel fitment than they were to damn close before the swap...
 
1WildRT said:
.26 in basically a quarter of an inch, and that's track width so for both wheels... That means one eighth of an inch per side.... If one eighth of an inch causes a issue with tire/wheel fitment than they were to damn close before the swap...
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That’s not how Wilwood specs it. It’s listed as “hub offset”, not track width. It’s per hub, so that’s .52” to the track width.

newguy said:
One kit I'm considering is 140-14271, that hub is listed as 2.76" and I could not get a caliper inside the cop wheel to measure, but measured the hubs on my 74 disc brakes and that measurez 2.8", so it will fit BUT it states it increases the track width .26", so I'll need to mount the wheels again and see if I have that much room to clear inside the fender
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It’s compared to the Mustang hub. So unless you’re already running the HDK with factory Mustang II hubs putting the wheels back on won’t help you.

You’d have to add .52” to the track width of the HDK and then compare that to your current track width.
 
72bluNblu said:
Have you asked @HemiDenny? I'm sure he has an idea of what some of his customers are running for brakes and wheels.

The other thing is, I don't think the Wilwood hubs will clear the factory cop wheels to begin with, regardless of the rotor size. The hubs used with the Mopar Wilwood kit definitely won't, the hub diameter is significantly larger than the hub bore on the cop wheels. Not sure about the MII kit. Do you have the part # for the Wilwood kits that you want to use?
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I have wilwoods all the way around on my car, the cop wheels fit. Not sure if this helps you sense you posted this in Nov

IMG_1403.jpeg
 
Kern Dog said:
I agree that the lever arm of a larger rotor does have an impact but if a tiny caliper is pinching a huge rotor, I don’t see the rotor size slowing the wheel any faster. A tweeker with a 3 foot breaker bar won’t crack a nut loose quicker than I could with a standard ratchet.
There is a principal known as “the point of diminishing returns”.
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I'll respond to this because I believe the author has me "ignored" and the rest of you can avoid the drama.

I disagree It's not a case of diminishing returns. Because if a wheel locks in hard brake application, there are effectively no returns. The driver is along for the ride.
Tuning your brakes for best balance is a worthy goal, unfortunately that goal does change dynamically for many reasons that a driver has to account for, but getting the brakes balanced by whatever means, tire size, tire compound, air pressure, brake compound, proportioning, rotor diameter pad area, piston area. F/R Weight, aero effects, chassis dive, etc is a very worthy goal. A simple panic stop test in representative conditions will quickly and easily indicate the success of brake balance for that condition tested.
The goal of a street vehicle normally is for fronts to lock up first in dry conditions with no ABS in a straight line.
It also should be possible to lock up all four tires simultaneously , or some braking/traction capacity is being left on the table, ie you have more tire than brakes.
My favorite line on the topic, "brakes stop the wheels, tires stop the car"
 
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sndbox22 said:
The front kit 140-11023, rear 140-11386. Got Them 2021
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So, the reason why I said they shouldn’t fit is because Wilwood says they shouldn’t. This is the instruction sheet for that kit

IMG_5633.png


The diagram indicates the base radius of the hub snout is 3.24”, and the instructions say the minimum hub bore for the wheel should be 3.24”.

The minimum hub bore on a set of Mopar cop wheels is usually somewhere between ~2.8” and 2.9”. Less than 3” certainly, at least all the ones I’ve seen.

So, my concern would be that the hub bore of the wheel is sitting somewhere on that radius, and that would mean the wheel wouldn’t be sitting flush against the face of the hub, and that the lugs are distorting the wheel to clamp it all together.

I haven’t mounted them up, so I can’t say for sure. But that combo doesn’t fit according to Wilwoods instructions.
 
72bluNblu said:
So, the reason why I said they shouldn’t fit is because Wilwood says they shouldn’t. This is the instruction sheet for that kit

View attachment 1716185465

The diagram indicates the base radius of the hub snout is 3.24”, and the instructions say the minimum hub bore for the wheel should be 3.24”.

The minimum hub bore on a set of Mopar cop wheels is usually somewhere between ~2.8” and 2.9”. Less than 3” certainly, at least all the ones I’ve seen.

So, my concern would be that the hub bore of the wheel is sitting somewhere on that radius, and that would mean the wheel wouldn’t be sitting flush against the face of the hub, and that the lugs are distorting the wheel to clamp it all together.

I haven’t mounted them up, so I can’t say for sure. But that combo doesn’t fit according to Wilwoods instructions.
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I have Wilwood IMO rather generic alum hubs on a few of my cars. I have a very low affinity for their robustness.
The Dr Diff Alum Mopar Hub is far superior strength wise IMO. Unfortunately, both are stuck with a lame bearing size for any HP track day use, again IMO.
Keep in mind, alum loses 50% of its strength at fairly low temps, and few cars here make much attempt to supply additional cooling for often undersized front brakes in the first place, meaning hot hubs.

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72bluNblu said:
So, the reason why I said they shouldn’t fit is because Wilwood says they shouldn’t. This is the instruction sheet for that kit

View attachment 1716185465

The diagram indicates the base radius of the hub snout is 3.24”, and the instructions say the minimum hub bore for the wheel should be 3.24”.

The minimum hub bore on a set of Mopar cop wheels is usually somewhere between ~2.8” and 2.9”. Less than 3” certainly, at least all the ones I’ve seen.

So, my concern would be that the hub bore of the wheel is sitting somewhere on that radius, and that would mean the wheel wouldn’t be sitting flush against the face of the hub, and that the lugs are distorting the wheel to clamp it all together.

I haven’t mounted them up, so I can’t say for sure. But that combo doesn’t fit according to Wilwoods instructions.
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I have the wheels on my car, I have on issues going down the road with these wheels. Was just trying to help.
 
sndbox22 said:
I have the wheels on my car, I have on issues going down the road with these wheels. Was just trying to help.
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Hey I’m just trying to help too. Steel wheels will distort when you tighten them, so you may not notice any issues in the short term.

But in the long term, if the center bore of the wheel is sitting on that hub snout radius before the mounting surface is flat against the hub you could end up with metal fatigue on the wheel or the hub, which could lead to failure. The likelihood of that is pretty small with the amount of miles most people drive these cars, but a wheel/hub failure isn’t something I’d mess around with, even if the possibility is tiny.

Do you have any close up pictures of the center bore of the wheel or the hub? With the wheel off you should be able to see the spots where the wheel sits on the hub. If the witness marks are clear of the snout radius than all should be good.

The Wilwood instructions are very clear, and the difference in their recommendation for the hub bore at 3.24” and the hub bore of the cop wheels (<3”) is huge, hence my skepticism. But a couple pictures would take care of that, and could be very helpful for other members considering Wilwoods if their recommendations are that far off.
 
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72bluNblu said:
Hey I’m just trying to help too. Steel wheels will distort when you tighten them, so you may not notice any issues in the short term.

But in the long term, if the center bore of the wheel is sitting on that hub snout radius before the mounting surface is flat against the hub you could end up with metal fatigue on the wheel or the hub, which could lead to failure. The likelihood of that is pretty small with the amount of miles most people drive these cars, but a wheel/hub failure isn’t something I’d mess around with, even if the possibility is tiny.

Do you have any close up pictures of the center bore of the wheel or the hub? With the wheel off you should be able to see the spots where the wheel sits on the hub. If the witness marks are clear of the snout radius than all should be good.

The Wilwood instructions are very clear, and the difference in their recommendation for the hub bore at 3.24” and the hub bore of the cop wheels (<3”) is huge, hence my skepticism. But a couple pictures would take care of that, and could be very helpful for other members considering Wilwoods if their recommendations are that far off.
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There is room around the hub, the wheel sits flush on the rotor.

image.jpg
 
sndbox22 said:
There is room around the hub, the wheel sits flush on the rotor.

View attachment 1716185827
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Thank you sir!

Makes me really wonder about Wilwood’s instructions, but that looks pretty good to me, that wheel should be sitting flat on the hub based on that picture. Thanks for posting that! I will have to adjust my advice, because I’ve had it wrong based on Wilwoods instructions.
 
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72bluNblu said:
Thank you sir!

Makes me really wonder about Wilwood’s instructions, but that looks pretty good to me, that wheel should be sitting flat on the hub based on that picture. Thanks for posting that! I will have to adjust my advice, because I’ve had it wrong based on Wilwoods instructions.
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No problem, happy new year
 
newguy said:
This helps, I have been holding off since I could not get anyone that would post that they had a setup that did or did not work.
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There’s another option, do what I did, I used cordoba 11.75 rotor and fabricated a bracket to mount the wilwood D52 caliper onto the Mopar spindle

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