The rearend authorities at...
The rearend authorities at Currie Enterprises take Max Effort's Speedway Engineering housing and add a bulletproof third member that's ready for race.
When we left off with the rearend for Project Max Effort in the December issue, Speedway Engineering had worked their special blend of magic on one of their Grand National series 9-inch floater rearend housings, dialing in both camber and toe, but that's as far as Speedway takes these beasts. So to fill it up with the guts that will make it go we journeyed 60 miles south to Anaheim, California, to Currie Enterprises.
Currie makes their own rearend housings from scratch as well, including drag race, off-road, full custom, and mil-spec pieces-as a matter of fact, they were prepping a shipment of replacement rearends headed to our troops in Afghanistan when we arrived. But when it comes to cambered rearends like the one for the Max Effort '67 Cougar, Currie often works with Speedway Engineering, since they are one of the few outside companies whose quality meets their high expectations. Speedway feels the same way about Currie's renowned centersections and parts; they're some of the best available anywhere.
We hate spiders dangling over...
We hate spiders dangling over our heads, so you'll have to trust us that the original crusty and greasy 8-inch rear with an open diff and 3.00 cogs is still under Max for now. We'll give you
a good comparison shot when we fumigate it and pull it for suspension work.
To say the Currie family is particular about quality would truly be an underestimation. Here's a good example: To ensure that every piece they need for their rearends is top-notch without fail, Currie manufactures nearly every part that goes into their rearends and third members in-house, or works with outside vendors to have parts made to their specifications.
Centersections, pinion supports, axles, axle tubes, yokes, gear cases, it's all Currie spec and stringently controlled. That goes right down to the bolts; Currie couldn't find a consistent supply of what they needed, so they launched their own proprietary line of nuts and bolts. Need any of that stuff for your 9-inch? It's all improved, but almost all of it will work with original housings as well-and all of it is available to consumers in Currie's rearend builder catalog.
We'll be using Currie's nodular...
We'll be using Currie's nodular iron 9-Plus big-bearing pinion support since it has a 50 percent larger (than stock 9-inch) heavy-duty bearing to stabilize the pinion head under the extreme loads delivered by high horsepower. It's designed for Currie cases, but will fit any 9-inch.
So with our bare Speedway housing, we told Currie our goals, and they spec'd out the ideal package that would not only stand up to the planned power and abuse, but do so for years to come. If you like what you see, everything is available to create your own combo. Want an actual Max Effort-spec rearend of your own, complete end to end with hubs, axles, brackets, brackets, third member, and even an innovative Baer Brakes system? Just give the boys at Cortex Racing a call; Max's rearend is one of the components that will be orderable and customizable to fit just about any muscle car.
On The Web
Want to see the key differences between Currie's cases and a stock Ford Nodular 9-inch? Check PopularHotRodding.com for the web-exclusive story.
Speaking of specially designed...
Speaking of specially designed parts, everything you see here is specifically designed to Currie's demanding specs and only available through them. The Loctite splashed bolts are even marked CE. If you need anything for a 9-inch, Currie is who to call.
We'll be using Speedway Engineering's...
We'll be using Speedway Engineering's 31-spine crowned axles, but these Timken bearings use special races designed by Currie. These allow for an easy upgrade to 35-spline axles for anyone needing more, just by swapping out the bearing and races rather than the entire case.
To begin assembly, the pinion...
To begin assembly, the pinion support is pressed onto the pinion gear.
With our 4.10 gears mounted...
With our 4.10 gears mounted in the case, Currie checked the backlash and set it to .010 inch, per Motive Gear's spec. Not all brands are the same, so as a rule of thumb always follow the manufacturer's recommendation.
For our differential, we needed...
For our differential, we needed exceptional torque transfer and power handling capability, but we drew the line at a complete race differential that requires frequent maintenance in favor of Eaton/Detroit's strong and reliable TrueTrac. For those not familiar with what makes this piece superior to traditional clutch-style limited-slip diffs, check out Tech Letters in this issue.
Currie rarely has an issue...
Currie rarely has an issue with noise using gear sets from Motive Gear-which is why that's the only brand they sell-but to ensure proper alignment, the gears are spun with dark and light grease splotches so the Currie technician can see the meshing pattern of the teeth.
With everything checked out...
With everything checked out and torqued to spec, the third member is lowered into the Speedway housing via an electric winch. A Currie lightweight or aluminum gear case would have saved a good deal of weight, but we need the sheer strength and rigidity of good old heavy nodular iron.
Our gear case of choice was...
Our gear case of choice was Currie's 9-Plus Race Case. It may look familiar, but this completely reengineered nodular-iron piece is over 100 percent stronger than a stock 9-inch, and can handle up to 850 hp, thanks to upgrades like extra ribbing and bearing supports. It's also ideal for dealing with the loads that will be transmitted by Max's torque-arm-based rear suspension.
Remember that brake breakthrough...
Remember that brake breakthrough we mentioned in the last installment? May we present Baer Brakes' new internal parking brake assembly for 9-inch floater rearends. The brilliantly simple piece will relieve our fears of slipping out of gear while parked, and probably even work with the stock Cougar/Mustang parking brake handle. Watch for more on this one-of-a-kind brake option later.
Not just any axle can be used...
Not just any axle can be used with a cambered housing; our sticks are Speedway Engineering's crowned 31-spined axles, gun drilled for weight savings. This is the only correct way to run a cambered rearend with offset hubs and make it last. Those massive wheel studs are mounted in a Baer Brakes rotor hat.
After sliding on the retaining...
After sliding on the retaining plate and tightening its two retaining screws, a plate with three Allen screws caps the axle. Now you can see why it's so easy to swap out axles in a floater if necessary-and why they're safer in the event of breakage.
That big beautiful monoblock...
That big beautiful monoblock of billet astride a 14-inch rotor is Baer Brakes 6R series Asphalt Competition brakes-ideal for those times when you're doing 160-plus mph on the back straightaway headed into a tight right and absolutely must stop right now without fail. Based on Baer's 6S architecture, these brakes step up the features for serious competition cars. There's an internal crossover to prevent fluid circulation restriction, bridge bolts, and a quick-change clip to allow the option of quick pad changes in endurance races. That's an industry first, and exclusive to Baer Brakes.
Our rearend is complete, but...
Our rearend is complete, but before it can be installed we've still got lots of chassis and suspension work to do. We may be a bit overkill with those big bad 6Rs and 14-inch rotors on the rear, but only high-speed track testing will tell for sure. We'll let you know.