1970 Dart Kelsey Hayes Disc brake upgrade and 14x4.5" SBP wheel caliper clearance

I have a 1970 Dodge Dart 225 Slant-6 with 14x4.5" small bolt circle wheels and 9" front drum brakes. I am considering a Kelsey Hayes style oem disc brake upgrade from the company SSBC but am worried that the 14x4.5" small bolt circle steel wheels may or may not clear the calipers. I have measured my wheels narrowest internal diameter to be 12" just. According to the technical data provided by SSBC they indicated a total diameter for the brakes to be 11.36" (5.68" Radius x2) and if compared to the narrowest area of the wheel it makes a close fit but "technically" possible.

The kit I am looking at is for a 1969 Plymouth Baracuda part #W153 using 10" brake spindles which I would also need to do the disc upgrade. In the application listing it states that it fits with 14" wheels but does not specify if they mean Rallye wheels or Black Steel wheels like what I have. If they consider the 10" brakes to be V8 spindles I worry they assume you will be using Rallye wheels. While doing research about this topic I came across a review for this application on Summit Racing which read as follows and confirms my concerns even though the technical data seems to show that the brakes will clear without interference with the wheel: My question is has anyone successfully done this upgrade to their A-body using the 14x4.5" steel wheels?

DISC BRAKE KIT - FRONT - 4 PISTON - 11 INCH ROTORS - V8 SPINDLE - W153

"SSBC Ad for this kit misleading about 14" wheels !"

icon-favicon.gifSummit Racing Verified Purchase

SSB-W153
Apparently the only 14" factory steel wheels that clear calipers are the the Mopar Rally's, all other factory black 14" steel wheels rub/interfere with outboard side of calipers (unless widened).Instructions don't specify caliper install with bleeder up, had to use undersize axle nut cotterpin or drill out axle shaft to bigger diameter hole. All in all seemed good quality kit, but they should modify their wheel fitment statement to clarify, because their cross sectional diagram is not very helpful when most wheel manufacturers don't publish the dimensions of inside of bolt flange to area where caliber rubs only offset and backspace! "


https://www.summitracing.com/int/parts/ssb-w153/overview/year/1969/make/plymouth/model/barracuda

SSBC W153 Front Kelsey Hayes Style Brakes1.jpg
Link to SSBC directly: Disc Brake Kit - Front - 4 Piston - At the Wheels only - 11 inch rotors - V8 Spindle - W153


SSBC W153 Front Kelsey Hayes Style Brakes.jpg

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