Technical Big Wheel Spacers to Clear Calipers

Hello all,

I’ve got a 1964 Malibu that I’m converting to four wheel disc brakes.

I like the look of the car and really don’t want to change out my wheels and tires but these 14x6.5” wheels aren’t going to clear my new calipers.

For the fronts I can probably get away with 0.25” spacers and some minor grinding but the rears are another story. For the rear wheels I’m going to need about 1.5” spacer-adapters.

This car is just a boulevard cruiser - I’m not drag racing anyone or high speed cornering. What are your thoughts on using these wheel spacers, especially those big ones in the rear?

Thanks all.

 

Bad idea in my book, just from an appearance perspective. From the stated intended usage I wonder why discs, especially the rear, would be desired. Probably not what you wanted to hear, but you did ask!

Chris

 

You should not have an issue with the the spacers ( I’m ***uming your using the billet bolt on ones?)

but with stock offset wheels it’s gonna look weird.

my suggestion is going with a different offset wheel ,and bump up to a 15’

some folks say you will get premature wheel bearing and axle bearing failure with spacers , I think that only applies to the trucks and sinks that use those big 4” plus spacers and push the wheels right out to nowhere .

 

If that were me I would be looking for some deeper discs and move the caliper inwards, certainly on the back if not the front.

 

Bad.
A poor band aid fix.

 

Are all 4 wheels the same? Odd you would have to go with such a different offset on the rear.
Im ***uming you went with bigger diameter discs. In the 3rd Gen Fbody group many just upgrade to a larger front disc and leave the rears alone.
Regardless of how it’s going to look(odd in my mind from the rear) do you have the clearance to move the rears out 1.5 inches?
Also, many 3rd Gen F body folks use 4th Gen wheels, they run a 2.5 inch spacer in the front and a 1.5? In the rear to correct for the 4th Gen offset wheels.

I remember questions like “how often should the spacers torque be checked”? The guys who ran them would reply with “”how often do you check the torque on your wheels now”?

 

If you are just “boulevard cruising” as you stated, I don’t see a need for rear discs. If you have the stock width rear still in the car, and the rear wheel wells have not been altered, I don’t think you have room to push the rears out 1.5 inches. I have a 64 elCamino in the shop now, and those rear wheel wells are pretty tight and low.

 

Don’t they sell kits for 14” wheels?

 

I avoid rear discs on street cars, especially if I need the parking brake.

 

The rule of thumb is: If you can lock up all four wheels on clean dry pavement you don't need more brakes, you need more tire.

Another rule of thumb: Just because you can, doesn't mean you should.

Another rule of thumb: Don't fix it if it isn't broke.

If you simply must keep your wheels, you might try swapping out the wheel hoops and re-using the wheel centers; on the old Chevy's you can swap out the old wheel hoop for ones from a Ford pickup, the Ford wheel hoops are a little wider, have the safety bead and are designed to clear disk brakes.

Oops!, for some reason I was thinking you had 15" wheels when giving advice, still, keeping your wheel centers and replacing the wheel hoops is an option (measure the diameter of your hoops then check with some of the wheel manufacturers), also, the 80's G-body cars used 14" wheels.

 

Most of the people I've talked to that have done rear wheel disk change overs would not do it again.

 

Do not know about that. But if OP want's to retain original wheel covers then early S10 wheels would be better than spacers.

 

One change always leads to another, or cause and effect. This is the result of not doing your Homework. Odd's are real good if you use those spacers next will be cutting the wheel wells open. You probably won't see that coming either till you there.

 

I've got a 67 Chevelle, basically the same wheelwells you have, and they don't have a lot of extra space. Can you really fit a 1.5 spacer and not s****e your tires on the wheelwell edge? You must be keeping the small tires. Which begs the question, why the need for the big brakes?

 

In your high society, you cry all day
We've been so busy keepin' up with the Jones
Four car garage and we're still building on
Maybe it's time we got back to the basics...

 

What wheels are on it now? Stock?

 

Go 15" on the back, get more of the big & little's look.

The problem with the spacer on the front is it will increase scrub radius, but 1/4" isn't much. We see far worse than that with finned Buick drums on hot rods all the time, and nobody says anything about that.

 

Wilwood kits include a 1/4” spacer with every kit. I agree with all who feel rear discs are not needed.
Do you already have the parts and what are they for? A 64 10 bolt rear has pretty small brakes stock and most kits today are for 16” or bigger rims. if better brakes are wanted see what’s available stock on GM cars using 10 bolt rears in bigger cars.

 

I know kits are available for 14” wheels for Fords and mopars and I would ***ume GM also as they had them from the factory.

 

Gotta ask why.

Changing to disc to say you have disc, but keeping 14x6.5 wheels and tires. Agree with comments on tire will be your limiting factor, not your brakes.
Also agree when you throw on a spacer the wheel will likely hit the fender lip

If your set on going to disc, you need a rim that will fit over. Either get a disc brake kit that will fit inside a 14" wheel. Which won't give much more performance than a drum. Or move up to a 15" wheel that will clear the disc's.

Here's another option, Ecklers has 14" wheels to clear disc brake swaps. You'll have to verify if it will work on your disc swap.
https://www.ecklers.com/tech/cl***ic-chevy/57-64-disc-brakes-with-14-wheels

 

There's several things that don't appear 'right' here... First, just what wheels do you have? Are they drum brake or disc brake wheels? Disc brake wheels use a different hoop to give clearance for the calipers. Do you have disc wheels in the front and drum wheels in the rear? Second, it's odd that you have so much less clearance in the rear. A properly-sized brake system will normally have larger discs or drums in the front (where most braking is done), it sounds like the rears you have are too large for the application. If the fronts almost clear, the rears should clear, ***uming the same wheels on all four corners. Pictures of the offending parts would be helpful.

Spacers that thick are very likely going to cause clearance issues in the rear. If you decide to go with them, I'd highly recommend installing longer wheel studs rather than using adaptors. But different wheels and/or smaller rear brakes would be a better solution.

That's not really true. Ideally, you should be unable to lock the brakes, but given all the variations in conditions, tires, weight bias, etc etc this is rarely possible all of the time. And you never want the rears to lock first. The big problem is the majority of OEM drum brakes are a self-energizing design, which while good for reducing pedal effort, makes modulating application at or near the system limits very tough without them locking up. The difference with discs is they're NOT self-energizing, which is why Detroit made the switch. There's several other advantages to discs, but that's the big one.

 

This has been discussed to death with early vw rabbits

there is 0 benefit in swapping tje rear drums over to disc.

ive owned multiple of these rides snd did the disc swap on 2 first one cause I didn’t believe the stories , and the 2nd simply for the look .

a good disc / drum combo is my favourite braking system as you get the “grab” of big disc brakes up front , but a nice firm pedal with the rear drums adjusted correctly.

a disc / disc car always has a bit of a “mushy” brake pedal.

 

It's good to see someone else on the HAMB posting this kind of info, maybe others will start to pay attention. Typically people think a swap to disc brakes is done to increase braking forces, but the improvement disc brakes bring is in control and feel, which is important when braking at the limits of tire adhesion. As you've correctly posted, self actuating drum brakes may reduce pedal effort, but they reduce the ability to control braking forces at the limits of tire grip, as well as feel for the driver at the pedal. You go from maximum braking performance to locked up in a split second, and once that happens it is very difficult to get the brakes unlocked without losing all pressure in the system and starting over. In a panic stop situation that is a recipe for disaster. Modulating self energizing brakes at the limit of tire adhesion is very difficult. Unless a person practices it routinely they simply are not going to have the skill in an emergency. The common result is just a long skid, and black marks left on the road, until they hit whatever they were hoping to avoid.

 

Mother Mopar had drums figured out. But they are a b-word to set up correctly compared to all the others. But well worth learning how and getting the tools to do so.
Way back when I put a 12” mopar setup on the front of a 58 F100. Great brakes! Fixed that rear lock up first problem the right way!

 

First off a big thanks to everyone here - you all are a wealth of knowledge and I appreciate everyone sharing!

More info on my application:

The motivation to swap to four wheel discs was two fold: (a) Install drop-spindles and (b) address various intermittent issues in my current all-drum setup.

Yes, all of my wheels are the same: Original 14x6.5” drum brake wheels with 205/75 tires. Not exactly a performance setup - I know.

The parts I’m trying to use are from kits from Summit and Jegs. I’m currently test fitting them all on my spare tire rim. I didn’t expect the front and rear rotors to have such different offsets - between brake surface and wheel mount surface.

Am I maybe missing something or am I just trying to make old wheels work where they shouldn’t? Ideas on 14” disc brake wheels that would be compatible with my stock wheel covers?

 

Take note of many former posts. You are trying to change rear BRAKES when you shouldn't. It's not the wheels.

1/4" front spacers not so bad.

 

Well, I think you need to check clearance for what you need. You can get an idea with your spare. Say the wheel needs 1/16th of an inch to clear, or does it need a 1/2 inch to clear your calipers? I/e things are not generic with kits, what wheels worked fine on a factory disc car, may not work if you went from a 10 inch rotor to abs 11, 12, etc.

Meaning a “14 inch wheel to clear the factory calipers” probably won’t work with a larger aftermarket rotor.

 

Yeah, every time I see somebody say 'I can lock up my drum brakes now, why do I need better brakes?' I want to scream...

I will concede that installing larger newer drums on pre-war cars can offer a real improvement with a sharp driver, but by the late '50s drum brakes were very near their limits in available improvements for OEM applications. The cars had gotten heavier and faster, and the wholesale switch to 14" wheels only exacerbated the problem. If you want to see what it took to get drums to the next level, check out what the NASCAR boys had to do before discs were allowed.

Chrysler was one of the very few OEMs to use non-energizing drums, which was a superior design. But IIRC, even they eventually abandoned that design due to the inability to make them self-adjusting, a popular feature. Yes, they are a PITA to adjust properly.

Discs address all these issues. Besides not being self-energizing, they also don't require any adjustment, and the other big thing is they shed heat much better compared to drums. If you live in the flatlands that may not be important to you, but I live where there's a lot of mountainous terrain and not running out of brakes coming off a mountain p*** is a big deal.

 

That's probably most if not all of your issues. Get a set of discs brake wheels, and anything you can currently buy new will be disc brake types. If you're running full wheel covers, they'll fit, if using dog-dish caps you'll probably have to track down a used set. You'll probably have to choose between 6" or 7" width, the 6.5" size isn't common anymore.

If you're handy, you could knock the centers out of yours and install them in new hoops; that will probably be the cheapest option.

 

Keep the drums on the rear, you won't see them with stock wheels, you won't pick up performance.

Check if the kit you looking at moves the front wheel mounting surface (WMS) outboard from stock - most kits do. How much ? May not make a difference with a 14x6.5 wheel