Decision: 5x4 (SBP) or 5x4.5?

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Rod 69 Cuda

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Howdy, I'm facing a decision on my 1969 Cuda rebuild.

Question #1: Should I go with 5x4 (SBP) or 5x4.5? What are the advantages and disadvantages or each? I already have these in photo. They appear to be original, 5x4 (SBP) and are 14 inches by 5.5 wide. Someone told me they are somewhat valuable and desirable. Should I keep them or move on to 5x4.5 so I have more options? I'm trying to stay original, does the bolt pattern really matter?

Question #2: I want to go with power disc brakes on the front, but can only locate the 5x4 (SBP) at PirateJack.com. Is that a good conversion kit? Anyone have insight into that conversion kit? Or again, should I go with 5x4.5 so I have more rim, tire and brake options?

Question #3: Should I convert to 4 wheel disc, or is it not necessary? Any advantages of 4 disc vs. 2 front in terms of maintenance, ease of install, etc.?
Apprecaiate all feedback, thanks.

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If it’s not an OE correct build my vote is get 73 and up spindles with 5x4.5” bolt circle. Yes- For wheel selection, and ease of getting replacement parts for the brakes, they are everywhere.

Apparently 14x5.5 sbp wheels are harder to get. If you find out what they are worth (real world value, not EBay prices which are way to high) let me know. I have two to sell

Disc on the front is enough. @72bluNblu has the info on rear brakes and what works, he’s the guru
 
Only advantage to SBP is originality and and stock wheel fitment. Disadvantage is limited wheel selection.

Advantage to LBP is larger wheel and therefor tire selection and Larger brake options. Downside is your track gets wider with and wheel offset becomes important.
 
Question 1: In terms of functionality, either one will work fine. Your current rims are somewhat desirable so if you change them don't throw them out - someone will want them. If you want to go the completely authentic route keep the 5x4 pattern. In my opinion there is precious little value in originality of that level, but that's just me.

The big advantage of the 5x4.5 pattern is in wheel choices. You have a selection of SBP rims available, but nowhere near what you can do with BBP. Also, if you stay SBP tire choice becomes an issue. If you want 17" or 18" rims it's all but non-doable on SBP wheels.

Question 2: Another front disc option is the original Kelsey-Hayes discs. They are SBP but spendy as they haven't been made for a while and never were growing on trees. I can't help with the Pirate Jack option, perhaps someone else can weigh in on those.

As info, I have one each of SBP and BBP set-ups. I kept the SBP on my Valiant partly because by the time I found out I could have gone BBP, I was already heavily invested in SBP so I decided to keep it. I was able to find the rims and tires I wanted so I'm OK with staying SBP. However, I'm on the hunt for a 69 Dart, and I already have a pile of parts, including the 73+ front disc conversion to BBP, a new 8-3/4 in BBP.

Question 3: For most any kind of normal street driven car, front disc with a larger (10" or 11") rear drum should handle your needs. This is one area others may have input that differs. Rear discs are available, and as your performance level goes up, so does the need for braking. Fast cars need good brakes. Faster cars need really good brakes!
 
Original steelies are awesome.

I leave mine in place with the original bolt pattern.
 
Wilwoods..the hubs come set up for smallbolt or large bolt pattern well worth the money spent,and they go on real easy no need to change the upper control arm like you have to do with the stock '73 and up crap!!!
 
I have both patterns in manual disc brake. The 67 Cuda has 11.75 pin discs up front and 11 x 2.5 drums with a custom, shortened, 4.50 BP 8 3/4 in the rear to keep the original track. It works real nice. But, if I had to do it again, I'd stick with the Original K-H 5 x 4.00 front discs. They work well and they are lighter. The A Body 8 3/4 only came with 5 x 4.00 pattern. The 68 and 66 formula S have the original K-H 5 x 4.00 BP front discs with the 10x 1 3/4 rear drums. All original, Done.

I don't see the point of rear disc brakes.
 
So first off, if you're debating SBP vs BBP and want disks, I assume you have drums. Which honestly means you already won't be original either way, even if you add SBP disks. It's a pretty small point to argue that you still have the SBP if you've already upgraded to disks.

Question 1:
The only advantage to keeping the SBP is originality. It has no other advantages IMO. It makes wheel selection difficult for anything other than original reproduction rims, and that limits you to 14" and 15" rims in a very small selection of styles and backspaces. That might not be a problem for you though depending on your plans for the car. If you're keeping 15" rims and narrow tires it doesn't matter much. If you want to use tires that actually grip and go to 17's or 18's SBP is a non-starter.

The advantages to going to BBP are numerous. The biggest thing for me isn't even the wheels, it's the brakes. Brake parts for the original SBP brakes are not always easy to find. Replacement drums weren't even made for awhile. Hubs are not reproduced, so if you damage a hub you have to find a good original replacement. Pads and shoes are available, but in limited compounds. The original KH calipers, while a multi-piston design, are known to have issues with sticking and seal maintenance. And like everything else they can be expensive and hard to find. The 73+ BBP calipers are readily available, they are reproduced and can be found original, rebuilt, or brand new reproduction. The large single piston is virtually maintenance free. Pads and shoes are available in more compounds, the larger wheel bearings are more common to find and allegedly last longer, the larger ball joints are stronger and won't require an adaptor. The only disadvantage is the wider track width, but really that's not an issue because most wheels for BBP are available with enough backspacing. For a frequent driver the BBP brakes are easy to find parts for and easy to maintain. And that's a big advantage.

Question 2:
The piratejack kit is a 73+ disk brake set up that uses a BBP rotor blank. It is then drilled for SBP and the hub is turned down to fit with smaller wheel hub bores that the original SBP wheels have. It uses 73+ spindles, so it uses the large upper ball joint which means either changing the UCA's or using an adaptor, just like a 73+ disk swap. It widens the track width the same amount, because it is a 73+ BBP disk set up, just with the small bolt pattern. So, advantage wise, it uses all the same parts as a 73+ disk brake set up except for the rotor, which is just re-drilled and turned down at the hub. It's the same swap except for the bolt pattern on the rotor.

However, the hub can only be turned down so far, and like some other aftermarket disk kits (wilwood) the hub is still too large to fit most original SBP wheels. PirateJack advertises that SBP drum wheels may not fit, and there have been members here that couldn't fit original SBP wheels. Wilwood is even worse, the hub is a larger diameter than the piratejack hubs. That means that your wheel selection is even MORE limited, because you have to find a SBP wheel with a large hub bore. Also the wider track is an issue too because you basically need a SBP wheel that has a BBP wheel backspace. Finally, the piratejack kit has had some production issues with the rotors. There's a big thread on the kit somewhere, I'll try to find it and link it. The brakes themselves work well, but honestly you should just go BBP if you want to use the piratejack kit. There's no reason to keep the SBP if you've gone to that kit. Originality is already out the window, and keeping the SBP adds even more wheel selection issues than if you used original SBP disks.

Question 3:
4 wheel disks really aren't necessary. Yes, they do improve stopping slightly. They're usually lighter, and you have the standard disk vs drum advantages - they adjust automatically, they work when they're wet, and they don't heat fade as fast. But if you've stayed with 15" or smaller diameter wheels you can't run a grippy enough street tire to need the improved stopping power. And if you're not driving like an animal at high speeds over long periods the rear drums don't typically fade much. If your road racing it might come up, but even autoX and spirited mountain roads won't typically be enough. The maintenance on the disks is easier, but rear drums last twice as long as the disks up front so maintenance isn't very frequent anyway.

Bottom line is the rear disks look cool, but aren't a very good "bang for your buck" upgrade. DoctorDiff is a great source if you want rear disks, his kits allow the use of the original tapered wheel bearings. Almost all others require the use of the "green" style bearings. Both work fine, I like the original tapered bearings. I run DoctorDiff's 11.7" rear disk kit on my Duster, it works great but the difference compared to the 11x2.5" drums I was running before is fairly small.

DoctorDiff is a great source for brakes for these cars, he carries everything you need for a BBP swap in the front and the rear. He has original style 73+ conversions, as well as upgraded options with larger diameter rotors. The factory offered 11.75" front disks on the B/R bodies that use all the same parts as the 73+ disks except for the rotors and caliper brackets, and that makes for a great upgrade in braking even compared to the 10.87" 73+ rotors. The 11.75's need a 15" wheel though.

Wilwoods..the hubs come set up for smallbolt or large bolt pattern well worth the money spent,and they go on real easy no need to change the upper control arm like you have to do with the stock '73 and up crap!!!

They don't go on half as easy as the original 73+ style brakes, you have to safety wire everything together which is a PITA. And if you do it wrong the hub can come apart. You don't have to change the UCA's for the 73+ brakes either, you can use a tapered adaptor if you like. Which is far better than using a 9" drum spindle with a design that even Ma Mopar didn't stand behind later. And the redesigned hub on the new Wilwood kit has a huge diameter, they don't fit any of the original wheels and not even some of the limited aftermarket wheels.

I recently pulled a set of wilwoods off a buddy of mine's Belvedere. Talk about a hot mess. Both calipers had two frozen pistons (one whole side on both). On one side a stud had broken, and because it broke behind the threads the safety wire did not hold it in place and it was backed out and rubbing on the caliper bracket. The previous owner had let the car sit which probably caused the sticking issue, so to be fair it was a maintenance issue. But I've never had an issue with the 73+ style disks. I've run calipers I pulled out of cars in the junk yard that had brown goo for fluid, a quick flush and everything worked great.

Wilwood's are for guys that like saying they spent the most money but aren't smart enough to know what they're actually getting.
 
Performancewise, it all depends on how you intend to use the car.
The biggest advantage of disk is cool off during repeated high speed or steep downhill use.

Weigh the various factors before committing.
Stock steel wheels will fit over either factory fixed caliper or '73 up.
Going wider on '69 Barracuda will use up precious clearance as mentioned by another poster. So you'll have to be more careful with backspacing and tire size choices.
Decide what you're doing for the rear axle to convert it to big bolt pattern.

Wheel choices have increased for SBP in the past 10 years or so. Still nowhere near the availability for 1/2", 5 on 4.5.
So maybe see if the wheels you want are only a BBP, then go from there.
 
As long as there are caliper parts for mustangs and corvettes, there will be parts for mopar K-H four piston calipers.
The availability of the mopar disks was very limited for a while, at least decent ones. Definately pick up a spare set when you have a chance.
Same with the drums. It was the rear drums that went unavailable new for a while - specificly the 10 x 1.75" drums with SBP.
10 x 1.75 drums with BBP had even less original use. Those are probably harder to find at times. Kindof like the Bendix 4 piston brakes used just a few years on b-bodies.
Point is, on older vehicles, parts available is never guarenteed.
 
As long as there are caliper parts for mustangs and corvettes, there will be parts for mopar K-H four piston calipers.
The availability of the mopar disks was very limited for a while, at least decent ones. Definately pick up a spare set when you have a chance.
Same with the drums. It was the rear drums that went unavailable new for a while - specificly the 10 x 1.75" drums with SBP.
10 x 1.75 drums with BBP had even less original use. Those are probably harder to find at times. Kindof like the Bendix 4 piston brakes used just a few years on b-bodies.
Point is, on older vehicles, parts available is never guarenteed.

That's not really true. The BBP disks and 10x2.5" drums that are used on A-bodies were used on cars well into the '80's for the disks and into the '90's for the drums. There are literally millions of cars with the 10x2.5" rear drums. "Guaranteed" is a pretty strong word, but getting 10x2.5" drum brake parts has never been an issue so far and with the parts currently being reproduced in large numbers it isn't likely to be an issue any time soon. The SBP stuff has already been out of stock on more than one occasion, A-bodies are the ONLY cars that use the 10x1.75" SBP rear drum stuff. So it's a really limited market, because not even all the A-bodies got 10" brakes. The KH stuff is easier for some stuff as you pointed out because of the Mustang crossover, but the Mopar specific stuff can be an issue. Seems like there are a lot of thread from guys looking for hubs. Granted, I also see that most of them find hubs relatively quickly, but that will eventually change.

It doesn't matter as much if the car isn't going to see a lot of miles. If set up with new SBP brake parts most folks don't drive these cars enough to get to the next brake job. For a frequent driver or something that uses its brakes hard (autoX, road race, etc) there's no way I'd keep the SBP stuff.
 
Whats the drivetrain?
Tires you'll be wanting to use?

SBP brakes are OK if your going with bias ply tires.
Its what they were designed for.
 
I don't see the point of rear disc brakes
For a streeter,I totally agree.
On the back, I got 295/50s on bbp15x10s, with 10x2 drums, NO brake proportioning, and she stops real fine at the speeds I drive.
Up front, you can run any discs you want, but I run sbp KH 4-piston jobs, because my14x7.75 period correct aluminum 5 on 4 kidney slots fit ,lol, and I run 235/60-14s on the front, cuz I like the ride of those 60s at 28 psi.,and that is about the biggest tire that fits on the 7.75 rim,and still steers decent; this for a car that is gonna be bashing curbs until I get the hang of 400 plus horsepower.
All my junk was collected since the 70s so I ran what I had, but I liked the aluminum slot-mags,since forever.
 
Wilwood's are for guys that like saying they spent the most money but aren't smart enough to know what they're actually getting.

Well not everyone is "CHEAP" like you some of us want quality parts on our cars..cause' we actually KNOW what were doing..cheap cheap cheap:rolleyes::rolleyes::rolleyes:
 
I'll say for power disk, the later booster may be easier and cheaper to source.
The correct master cylinder probably is also slightly more available, and certainly alum/plastic ones with the correct bore for the later system are.
However, the later booster may have been designed with a different pedal ratio in mind. Not sure '73-74 but later ones pretty sure did.
All stuff people have dealt with before so its hardly uncharted teritory
 
Small bolt Kelsey hayes discs are a way lighter set-up also....73- up very bulky.. I do understand small bolt wheel selection is limited, but I've been collecting 5×4 wheels since the 80's...I really like the 4piston set-up...not gonna waste your time with bullshit info...if you say you already have the small bolt setup. You can get rotors with big bolt from the ram man..if you wanted 5×4.5...
 
Well not everyone is "CHEAP" like you some of us want quality parts on our cars..cause' we actually KNOW what were doing..cheap cheap cheap:rolleyes::rolleyes::rolleyes:

I’m pretty sure it has nothing to do with ‘cheap’, and with a response like that I’m also pretty sure you didn’t really read any of @72bluNblu ’s post. He’s done a lot of work with brakes and conversions and I for one at least consider his opinions and input invaluable.

I’ve had Kelsey Hayes 4 piston (which had pistons seize up), weak drum spindles converted to Will wood disc (which had pistons seize up), and have also done several oem 73’ and up disc brake conversions on A and B body cars, and couldn’t agree with bluNblu more about which ones install the easiest. people talk about weight, how much are you saving in pounds and does it really matter anyway?
Having had them all, and Dollars to donuts for all the reasons listed in previous post’s my vote is for oem 73 and up disc brakes, with rear drum.
 
I’m pretty sure it has nothing to do with ‘cheap’, and with a response like that I’m also pretty sure you didn’t really read any of @72bluNblu ’s post. He’s done a lot of work with brakes and conversions and I for one at least consider his opinions and input invaluable.

I’ve had Kelsey Hayes 4 piston (which had pistons seize up), weak drum spindles converted to Will wood disc (which had pistons seize up), and have also done several oem 73’ and up disc brake conversions on A and B body cars, and couldn’t agree with bluNblu more about which ones install the easiest. people talk about weight, how much are you saving in pounds and does it really matter anyway?
Having had them all, and Dollars to donuts for all the reasons listed in previous post’s my vote is for oem 73 and up disc brakes, with rear drum.

35 pounds..and we'll agree to disagree to each his own..
 
I run stock bolt pattern 5 on 4 cause I like steelies and dog dish caps, I have 10 inch drums and Kelsey Hayes disc brakes on two separate cars, the ten inch stop better but the discs don't require adjust and get hot with a lot of use. If you know how to drive you should be fine. My brothers car has the big bolt pattern disc which are better than both set ups I have.
 
I run stock bolt pattern 5 on 4 cause I like steelies and dog dish caps, I have 10 inch drums and Kelsey Hayes disc brakes on two separate cars, the ten inch stop better but the discs don't require adjust and get hot with a lot of use. If you know how to drive you should be fine. My brothers car has the big bolt pattern disc which are better than both set ups I have.

Ummmm...cant see the lugs thru the dog dishes so why does that matter?

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Advice from not so smart new guy to Mopars. My drums all the way around with sbp worked fine. I upgraded to bbp front discs and rear drums just now (buttoning up the front end in the next couple days) because I went with an 8 3/4 rear end with 15in wheel and tires.

If you do it buy a complete kit. I had parts from the purchase of my car but even with having them I'm in it for almost the same $$ as if I would have purchased a pirate jack, wilwood kit etc. A full kit would have been roughly the same price and easier than sourcing all the parts or multiple runs to the auto store for the small things (which you will still have to do). Wilwoods are cool but I'd probably do the pirate jack kit with drilled and slotted rotors because $ and sourcing parts from the auto store vs from wilwood.

I have rear drums, but will probably go to discs next year because I'm short on space on my passenger side rear with 245s. Plus they look cool.

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I’m pretty sure it has nothing to do with ‘cheap’, and with a response like that I’m also pretty sure you didn’t really read any of @72bluNblu ’s post. He’s done a lot of work with brakes and conversions and I for one at least consider his opinions and input invaluable.

I’ve had Kelsey Hayes 4 piston (which had pistons seize up), weak drum spindles converted to Will wood disc (which had pistons seize up), and have also done several oem 73’ and up disc brake conversions on A and B body cars, and couldn’t agree with bluNblu more about which ones install the easiest. people talk about weight, how much are you saving in pounds and does it really matter anyway?
Having had them all, and Dollars to donuts for all the reasons listed in previous post’s my vote is for oem 73 and up disc brakes, with rear drum.

Stroked340 is one of those guys that thinks if he spends the most money he will always get the best parts. He also thinks he’s better than everyone else if he spends the most money.

Sadly, he doesn’t have the best brakes or the most money, but he’ll keep trying to convince other people to make the same choices so he looks better. He calls me “cheap” because he can’t make a good technical argument to support his opinion, so the best he can do is call me names. Of course even the “cheap” thing is BS, the DoctorDiff 13” cobra style kit I run on my Duster was more expensive than the basic low end Wilwood kit he runs.

As far as weight goes, even if the Wilwoods save 35 lbs vs the stock 73+ disks that’s not something you’ll ever notice on the street. It’s unlikely most people would even notice it at the track. As part of a whole car lightening effort it would help, but by themselves it’s almost nothing. Do you notice when you put a load of groceries in the trunk? Is that worth an extra $300? For a street car I would much rather trade a few pounds for better reliability and more robust braking.

The other thing is, the new Wilwood hubs will not fit ANY of the original mopar SBP wheels or ANY of the reproduction SBP wheels. They require a hub bore of 3.050”, which none of those wheels have. Even the factory BBP wheels have a smaller center bore than that. This has been discussed before here

Small Bolt Pattern Wheels Don't Fit Wilwood Disc Conversion

If you have to buy all new wheels anyway you might as well upgrade to BBP.
 
I run stock bolt pattern 5 on 4 cause I like steelies and dog dish caps, I have 10 inch drums and Kelsey Hayes disc brakes on two separate cars, the ten inch stop better but the discs don't require adjust and get hot with a lot of use. If you know how to drive you should be fine. My brothers car has the big bolt pattern disc which are better than both set ups I have.
If your up for it, see if there are other linings that provide the braking more to your liking.
I've experimented every time I've not been fully satisfied. Porterfield's street lining works pretty well for both disks and drums (currently what is on my Barracuda). A few of the guys here have really liked EBC Red stuff for the disks. D11 pads as you prob know. Like most of those types of materials, clean the rotor and bed in per recommendations. That still leaves the rear shoes to figure out. Rear is real important for how it feels and responds on the initial application.
Most replacment shoes and pads have edge codes with friction ratings. Its a very rough rating system but its better than nothing when comparing.
https://board.moparts.org/ubbthread...0239/brake-lining-edge-codes.html#Post2260239
Getting off topic here so we can take this to another thread if anyone wants to keep discussing.
 
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Well not everyone is "CHEAP" like you some of us want quality parts on our cars..cause' we actually KNOW what were doing..cheap cheap cheap:rolleyes::rolleyes::rolleyes:

So factory parts are cheap cheap cheap and poor quality...gotcha.
 
Advice from not so smart new guy to Mopars. My drums all the way around with sbp worked fine. I upgraded to bbp front discs and rear drums just now (buttoning up the front end in the next couple days) because I went with an 8 3/4 rear end with 15in wheel and tires.

If you do it buy a complete kit. I had parts from the purchase of my car but even with having them I'm in it for almost the same $$ as if I would have purchased a pirate jack, wilwood kit etc. A full kit would have been roughly the same price and easier than sourcing all the parts or multiple runs to the auto store for the small things (which you will still have to do). Wilwoods are cool but I'd probably do the pirate jack kit with drilled and slotted rotors because $ and sourcing parts from the auto store vs from wilwood.

I have rear drums, but will probably go to discs next year because I'm short on space on my passenger side rear with 245s. Plus they look cool.

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nice looking car. You didn’t have to change lower control arms to convert them, unless you just wanted refurbished ones ready to go.... you are right, sometimes rounding stuff up is a pain. When I do project like that I get everything I need prior to starting. When getting used spindles I always try to make sure they give you the dust shields, bolts and caliper brackets if they have them available. The rest can be bought new easily.

now that you’ve done the conversion you can get parts for them just about anywhere which is a huge plus.
 
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