The small drum spindle (shown on left) for drum applications up to about 1969 and also used on 65-67 Mustangs with Kelsey Hays 4 piston disks. A drum spindle is easily recognize by having 4 bolt holes (instead of 3 for disks) to mount the backplate. The small spindle uses A2 and A6 bearings with Nut size of 3/4 inch.

The larger drum spindle (shown on right) from 1970+ also has the same 4 bolt backplate pattern as used on the earlier small spindles but now has a larger spindle diameter and uses A12 and A13 bearings with nut size of 13/16 inch.

Both spindles types (with 4 holes) are interchangable and do well for the street but for racing application or just to beef up the early Mustangs front end a popular upgrade is to install the larger spindles. The larger drum spindles found in any 1970+ drum application bolt right up to an early 65-67 Mustang with Kelsey Hayes disks. Only mod required is to replace the early Mustang small outer Tie Rods with the larger tapered stud Tie rods found on later 70+ Mustangs.

The main difference between small block 221 260 289 302 351W and 351C bellhousings is the with the flywheel size. 157 and 164 tooth are the 2 versions of flywheels and each flywheel requires a specific bellhousing. The way each bellhousing can be identified is by looking at the starter position. more ...

Extensive descriptions and comparisons on Cobra's and other Ford parts. Great details. more ...

2 different INPUT shaft are commonly available for all V8 Ford's, 1 1/16" and 1 3/8". But both input shafts have the same number of splines of 10.

2 different bolt patterns. Early Toploaders used a narrow bolt pattern type for attaching the transmission to the bellhousing and the later versions used a wider butterfly type bolt pattern.

There are several differences between original and reproduction Cobra closed lettered valve covers. The biggest difference is the squared bolt cutout on the originals versus a rounded type cutout on the more ...

Not all fan clutch are created equal