Project Muscrate:

Strange Engineering going on!

Hi everyone and welcome back! Sorry for my absence the last couple issues but unfortunately I haven’t had the time I needed to get much done on Muscrate. Once again it has become clear I will miss another self-imposed deadline and Muscrate will not hit the track this year. I have managed to plug away on some items, though, and this month I will cover the components I am using to fill the 9-inch housing I fabricated. On to the taters.

When I need a part for my race car I always look for a company that first and foremost offers quality components and service and also supports the sportsman racer. So it was an easy decision to whom I would hand over my hard earned cash when I needed parts to complete my 9-inch rear end. Strange Engineering is a family-owned business based in Morton Grove, IL, and not only produces some of the highest quality rear end components and services in the industry but also has available top tier front and rear disc brake systems, coil over shocks, drive shafts, custom housings, and more.

The goal with Muscrate is to “over-build” some of the high stress areas so that I have a built-in cushion against breakage. But, at the same time I don’t want to add extra unnecessary unsprung and rotational weight. So, that moves me into the higher end stuff, which, of course, costs more.

But speed costs, so how fast do you want to go? I looked at the available options and then made a phone call (847-663-1701) to Strange to get some answers. I knew going in that I was going to need an aluminum center section to save weight and Strange has two different styles available.

Unfortunately for me and my wallet, I was advised that due to the weight of the car (3200 lbs. with driver) and predicted horsepower of the engine (secret for now) I would need to go with the Ultra Center as opposed to its lighter duty (and cheaper) little brother if I expected any “cushion” factor. And as a happy little extra there are some features of the Ultra that should translate into quicker ETs over the base unit.

The Ultra Center case is engineered to provide better lubrication to the pinion bearings and incorporates a unique pinion support that is fastened to the case with twelve bolts and has substantially larger pinion bearings than a stock unit, which provides much improved pinion shaft support and increases ring and pinion life. The pinion tale bearing is larger than stock and anyone who has ever cracked the stock Ford tail bearing bore will appreciate that feature.

The Ultra Case is available in three different bore sizes. The two that most of us will be interested in are the 3.25” bore that accepts 35 spline axles and 40 spline axles with a 2” spool bearing journal O.D. that some companies offer. The problem with using a 40-spline axle with only 2” spool bearings is the potential to distort and eventually fail under extreme abuse, such as high HP heavyweight cars.

So, the next step up is the “Mack Daddy” Ultra Case with the 3.812” bore. The 3.812” bore allows the use of a 2.25” spool journal without narrowing the bearing itself and losing strength. The larger size also provides a stronger spool for the ring gear to fasten to, which will help increase gear life. Another feature of the Ultra Case is the large chromemoly studs that are encapsulated by the large billet steel caps that allow for shorter and stronger studs to be used.

Strange also has available a lightweight Ultra Case which features a taper/ball bearing pinion support. The pinion support has been pocket milled for less weight and has what they call a “low friction angular contact pinion ball bearing”. That’s fancy speak for less drag and go faster!