Small-Block Mopar Stroker Dyno Test

This is what we started with. Hafliger bought a 360 long-block from a nearby junkyard for a paltry $150. Here it is after being hot-tanked and shot-blasted. "It was really crusty and full of rust, too," Hafliger said. Unlike their RB cousins, LA engines are everywhere, and people are practically giving them away.

This is what we started with. Hafliger bought a 360 long-block from a nearby junkyard for

We've often joked in these pages that the words budget built and Mopar can never be uttered in the same sentence. At least that's what we used to think.

Two months ago, we did a theoretical build of an LA engine using a 318 as the foundation. We cheekily referred to it as an almost-500hp engine you could build for a little more than $5,000. Well, we decided to take up our own challenge and assemble that small-block Mopar. With the help of Brian Hafliger of IMM Engines in Indio, California, we killed our horsepower goal, but we also overshot our budget by a similar percentage. Nevertheless, we still think of this as a good build. Chrysler guys, put this in your Duster and drive it.

CYLINDER HEAD FLOW
	BARE HEADS		WITH RPM	WITH SUPER VICTOR
LIFT	INTAKE	EXHAUST	INTAKE	INTAKE
0.100	69	58	69	69
0.200	141	119	139	140
0.300	197	161	185	190
0.400	241	184	215	227
0.500	267	193	230	242
0.550	271	195	233	245

To maximize the compression ratio, Hafliger decked the block to 9.583 so the piston would be 0.005 inch out of the hole. He ran his mill at half speed in case he wants to put MLS gaskets on this engine in the future. MLS gaskets require a finer finish than conventional head gaskets.
To maximize the compression ratio, Hafliger decked the block to 9.583 so the piston would
The bore on a stock 360 is 4.00 inches. Hafliger bored this block 0.040 over. To finish, he did a semismooth plateau hone with his Sunnen machine and cleaned up the bores with a brush. He said moly rings seat best with this type of finish.
The bore on a stock 360 is 4.00 inches. Hafliger bored this block 0.040 over. To finish, h
The 4.00-inch-stroke Scat crank is internally balanced, but it's not a bad idea to have your machinist double-check everything. The bob weight for our engine was 1,784 grams. All LA engines can take a 4-inch-stroke crank, but you should still verify your clearances. Not all rod and bolt packages are the same size.
The 4.00-inch-stroke Scat crank is internally balanced, but it's not a bad idea to have yo

In addition to the crankshaft, the Scat stroker kit included Scat 6.123-inch I-beam rods, Icon forged pistons with a 20.5cc stepped dish, a 1.465 compression height, low-profile Icon moly rings, and ACL bearings. The top two rings measure 1/16 inch and are gapped to 0.022 inch. The oil control rings measure 3/16 inch.
In addition to the crankshaft, the Scat stroker kit included Scat 6.123-inch I-beam rods,
The cam Hafliger chose was Comp's Extreme Hi-Lift XE295HL hydraulic flat-tappet grind. The specs are 251/257 at 0.050 inch and 0.564 valve lift on a 110-degree lobe-separation angle. Comp recommends installing this cam 4 degrees advanced. Using a nonadjustable Engine Pro double roller timing set, the cam ended up going in 5 degrees advanced.
The cam Hafliger chose was Comp's Extreme Hi-Lift XE295HL hydraulic flat-tappet grind. The
Here's the key to keeping the costs down: RHS' new iron cylinder heads. RHS has part numbers for the LA-style, shaft-mount rocker system or the later-model, Magnum-style, pedestal-mount rockers. RHS sells the LA heads bare for $318 apiece (the Magnum versions cost about $50 more). They have 62cc combustion chambers, 179/67cc runners, and are designed to work with 1.92/1.625-inch valves.
Here's the key to keeping the costs down: RHS' new iron cylinder heads. RHS has part numbe