Torque Ball Seal Assembly-DMI Style-Steel Housing-Fits 99% of Sprint & Midget Applications-Part#TBS2A07
Includes seal and cup.
The Seals-it Torque Ball Seal DMI style was designed to what appeared to be the most common motor plate style currently being used.
The aluminum "MPD" style bell housing and the steel "DMI" style housing are the only ones where we have physical confirmed the fit. To our knowledge, these comprise the vast majority of the parts in the field, and other bell housings, such as the Winters aluminum bell housing and the DMI aluminum housing appear similar to MPD, however, it is incumbent on the customer to trial fit the parts and confirm the fit.
The motor plate should be a "nominal" thickness of .375 (3/8"), +/- .019 (1/64"), with an I.D. hole of 6.0", +/- .019 (1/64"). Plate thicknesses or hole dimensions other than those specified WILL CAUSE PART MALFUNTION.
The only engine style this design fits is the Chevrolet crank shaft flange bolt pattern of 3.580" diameter, which is the most common in use. Note that this is the flange pattern used on the two piece oil seal crank shafts.
There may be some groups that require the use of "stock" crank shafts. One piece rear main seals used after 1986 have crank shafts with a 3.00" bolt pattern. The "cup" will not fit these.
This torque ball seal is designed to fit 99% of sprint and midget applications.
The seal is placed between the firewall casting and the engine plate with the rubber seal facing towards the engine.
By designing the seal this way it does not interfere with the small I.D. of the steel or smaller firewall castings.