Loose ends. They make up the majority of our projects, yet rarely does any magazine article do justice to those small, albeit important, components that are necessary to get the job done.

Our Project D150 was no exception. Certainly, rebuilding the engine to produce nearly double the horsepower and torque output of the Slant Six was a reasonable task. In doing so, it was well within the power range of a small-displacement Mopar small-block. Now the goal was to take the combination off the engine stand and get it firmly between the framerails.

Follow us through the minutiae involved with getting our D150 on the road, and see if our challenges assist you in getting your project further down the road to completion. Just click on the sidebars below to get the scoop.

Fuelish Endeavors
The lifeblood of any engine is gasoline. Functionally the original system would have worked fine, however, we needed a more aesthetically pleasing arrangement that also reduced the chances of vaporlock.

The majority of the work involved reforming the fuel lines from straight stock and efficiently routing them in order to gain both function and form.

Power Supply
From early on, we only considered Optima Batteries for supplying amperage. The aesthetic favorite not only looks good, but also fulfills the deep cycle needs of our D150, due to our audiophile status.

Detailing Details
A host of new wires to power the electric fan, signal the MSD Ignition, and route accessory cables required the use of wire loom covering. We turned to Techflex for the braided wire loom, which would give a finished look underhood.

Spark It Up
Proven ignition performance is easily accomplishable, thanks to MSD Ignition and its straightforward installation instructions, which incorporate factory components and aftermarket systems.

Cool Air
The nature of our accessory drives required simplification, as we added an aftermarket air conditioning compressor. Additionally, the opportunity to remove the water pump–mounted fan afforded us a way to remove the power-robbing effect of the cooling fan.

Even Cooler
Although the Slant Six is a venerable and efficient engine, it has a reputation for being a hot runner—and we’re not talking performance here. In order to alleviate the typical concerns of oil and transmission cooling, we added aftermarket coolers to reduce underhood temperatures.

Anyone who has attempted to replace a stock carburetor with an aftermarket unit has dealt with kickdown linkage. Fortunately for Mopar enthusiasts, they have a friend in Randy Bouchillon. Bouchillon’s Kickdown Cable Kit makes head-scratching completely obsolete.

Because we outfitted the Slant Six with a new Hooker header and Holley carb, the original kickdown rods would no longer work. Bouchillon sent us a TorqueFlite Kickdown Cable Kit that installed so easy, we’re still amazed. This kit works with most ’62-and-later Chrysler rear-wheel-drive vehicles fitted with a TorqueFlite transmission and just about any carburetor, including our Holley 2-bbl.

We took the truck to TMEC, a local exhaust shop, to have our new Gibson Cat-Back system and Random Technology’s high-flow catalytic converter installed. The experts at TMEC evaluated our exhaust system and the factory layout. The final result was clearly a custom exhaust system that looked good and cleverly evacuated the exhaust sound behind the passenger-side rear wheel.

Downright Polar
Creature comfort was definitely on order and as such, we opted for a little help from Vintage Air. We ordered a complete R134a system—with the exception of the evaporator coil, where the original sufficed. Our kit even included all the fittings, barrier hoses, and brackets, as well as a pressure switch and expansion valve. To keep things in the engine compartment uniform and looking good, we ordered the polished compressor and chrome drier.

Be Cool
The tanks on our original radiator were shot, and while we had made repairs previously, new leaks were now appearing. Rather than continue to repair the down-flow radiator into service, we turned to Be Cool, which built us a custom cross-flow, four-row radiator. The result was better coolant flow and lower engine-operating temperatures—certainly part of the equation for additional performance from our Slant Six.

The Results
To be brutally honest, we were a bit reluctant to discover the actual output of our Slant Six at Vinci’s Hi-Performance in Orlando, Florida. Would we meet our goal of producing V8 performance from the six-banger?

On the chassis dyno, we ended up with 140.1 corrected horsepower at the rear wheels and 194.0 lb-ft of corrected torque. According to Vinci’s, this equals 175 hp and 243 lb-ft of torque at the flywheel—a whopping increase of 85 hp and 83 lb-ft of torque as compared to a stock Slant Six.

We also widened the rpm range of power, and now the engine maintains an average of 120.5 hp and 178.1 lb-ft of torque through 5,000 rpm. And yes, it will break the tires loose!

Be Cool
MSD Ignition
El Paso
Best’s Lakeland Hose Service
110 John Carroll Rd. E.
FL  33801
Optima Battery Inc.
17500 E. 22nd Ave.
CO  80011
Bouchillon Performance
937 Commerce Circle
SC  29406
671 E. Edna Place
CA  91723
Random Technology
Gibson Performance Exhaust
3780 Prospect Ave.
Yorba Linda
CA  92686
2202 Hwy. 92 E.
FL  33801
Holley Performance Products
1801 Russellville Rd.
Bowling Green, KY 42101
KY  42101
Techflex Inc.
50 Stration Rd.
NJ  07871
Inglése Cool-Flex
400 S. Orchard St.
CT  06492
Vinci Hi-Performance
3915 El Rey Road
FL  32808
K&N Engineering
1455 Citrus Ave.
CA  92502
Vintage Air
10305 I.H. 35 North
San Antonio
TX  78233
  • «
  • |
  • 1
  • |
  • 2
  • |
  • 3
  • |
  • View Full Article