SPE has developed a drop-in spool kit for the S550 Mustang 2015-2023 to help combat issues with high horsepower applications.
The Ford Super 8.8 Differential is very strong. In a perfect world, going in a straight line, the LSD should apply even power to both rear tires. The factory LSD clutches were never designed to handle over 700hp. The car will become unstable and inconsistent when applying power beyond this level. In other words, if the chassis is upset or the track grip changes and one of the clutch packs fails to hold, the tire will grip and apply all the power to the opposing tire. If this happens, the car will pull and move in unwanted directions or, worse, cause a wreck. The SPE S8.8 spool kit corrects this issue by always applying even power to each tire. It can also fix issues on decelleration in a high grip situation where an LSD can be problematic.
SPE has designed our S8.8 spool kit to not only fix the downfalls of the LSD under high power but also strengthen the factory differential. The factory design applies the load through the spider gear pin bore into the carrier assembly. After load testing in simulation and in the real world, we improved upon it. SPE has moved the load to the clutch pack bore via our billet locking rings, which increases the carrier strength by 50% due to a much larger surface area to work with. SPE designed this kit to be drop-in and easy to install. We wanted the customer to be able to install the kit at home and not have to take it to a shop. There is no need to remove the carrier, only the differential cover. This means there is no need to do gear setup unless the gear ratio is changed.
*Does not fit performance pack differentials. These have a Torsen non-clutch plate-style carrier.