While not particularly known for its strength, the ubiquitous 8.25-inch rearend found its way under a whole slew of cars and trucks. Definitely not as sexy as the 831/44, a drop-in-style differential featuring the convenience of easy gear swaps or the nuclear bomb-proof Dana 60, but this Salisbury-style differential is plentiful and reasonably strong when healthy. In a perfect world each and every one of us could afford to replace that modest 811/44 with one of Ma Mopar's beefier offerings, but we most certainly don't live in a perfect world. What to do then? It's simple-give the folks at Randy's Ring and Pinion a call and order the parts necessary to reinforce your 8.25.
You will recall that our Project Stealth Bomber '89 Diplomat police car was being prep'd for the Nevada Open Road Challenge last May. We decided not to take our chances on the stock physically abused unit out back, and instead opted to freshen it up with a new sure grip and an even taller final drive ratio. Equipped from the factory with a 2.94 open diff, we calculated our gear ratio based upon cruising speed versus rpm. With a 28-inch tall tire and a 2.94 gear ratio, 110 mph would require 4,500 rpm while the same speed with a 2.76 gear and the aforementioned tires drops cruising rpm to a leisurely 4,000 rpm. So, we opted for the 2.7s. We also took the opportunity to install an Auburn limited slip unit. The experts at Ramjet Rear End Repair were given the stage to perform the task of bringing the Stealth Bomber's rearend up to speed.