Our JE forged pistons included wire locks for floating pin securing.
The wire locks are installed by working your way around the lock with a small screwdriver.
A nice option for wire lock installation is Lockintool’s W-927 installation tool. It takes some getting used to but, once you develop the knack, it’s a real time saver.
Here’s a [...]
Goodson reluctor ring installer jig is an absolute must for installing LS crank timing wheels.
The Goodson tool indexes the ring via the 8mm hole in the ring face.
The 8mm dowel is pictured here. It’s attached to a tang on the outside of the tool.
An internal dowel in the tool engages into the crank’s rear flange [...]
The side relief design provides additional clearance for the crank’s reluctor wheel. Without this added clearance, No. 8 piston would hit the reluctor wheel.
Here’s an underside view that clearly illustrates the side relief/short pin design. Naturally, this also reduces reciprocating weight as a bonus.
As you can see, the compression height resulted in the oil ring [...]
LS PROJECT, PART 2
BLOCK PREP AND BALANCING
by Mike Mavrigian
all photos by author
We swapped out the OE torque-plus-angle main cap bolts for a set of ARP studs. This will provide added strength and will eliminate wear on the block’s female threads during future servicing.
I recently visited Gressman Powersports where Scott Gressman decked our block, honed the [...]
Both rod and main bearings must feature a specified amount of crush area in order to achieve bearing lock-in within the housing.
The bearing shell outer edges (approaching the parting line areas) are larger than the saddle, which adds to the lock-in placement of the bearing shells.
Dirt particles or embedded blasting shot left behind in the [...]
CLEARANCES VS. CAVITATION EROSION
Cavitation erosion of a bearing occurs when rapid movement of the shaft away from the bearing surface causes vapor bubbles to form in the oil film. When these bubbles break, the resulting force causes erosion of the bearing soft overlay layer. Appearance and location of cavitation erosion will differ with operating conditions [...]
RACE BEARING TECH
The bearing gurus at Clevite share insight regarding current and future rod and main bearing development.
Installed bearing sets create a slightly eccentric bore, which promotes oil film capture and enables the rotational movement of the shaft to generate a hydroplane of oil film around the circumference.
Bearing crush is critical to holding the bearing [...]
Bearings may be sent to coaters for moly-graphite treatment.
The buildup of anti-friction coating is so minute that additional clearance compensation isn’t usually required.
Cam bearings (such as these from Dart) are available pre-coated, or you can send your cam bearings out for coating.
If you send bearings out for coating, don’t forget the thrust bearings. This anti-friction [...]
The valve reliefs were cut with precision. The intake pockets are 0.270″ and exhaust pockets are 0.064″.
Notice that the pin bore location encroaches into the oil ring groove. Diamond supplied a set of support rails that are installed prior to the oil ring package. These provide footprint support for the oil ring package.
Scott Gressman torques [...]
TOP FUEL RINGS & BEARINGS
It’s simply amazing that any components are able to withstand this nightmarish environment.
by Mike Mavrigian
A Dykes top ring from a Top Fuel engine.
(photo by author)
Note the missing plasma moly that was blown off of this top ring. This ring (and its companion set) saw a mere 24 seconds of running time, [...]
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