What should my main and Rod clearances be?
RPM, crank stiffness/flex, power level, and BLOCK STRENGTH, are all more important to bearing clearances than if its car, boat or airplane. Bonzen, if your mains come in between .002 and .003, and your rods come in between .00175 and .00275, put the damn thing together and run it.
Are there any bearing clearances for racing engines?
Engine connecting rod and main bearing clearances have tightened in recent years for many racing applications, but there are caveats to this trend that engine builders need to acknowledge before bending traditional guidelines, especially when adapting those practices to street engines. “It’s easy to whip these numbers out.
What’s the clearance on an engine that ran 6 years ago?
EngineLabs has seen a build book for an engine that ran six years ago, and the main clearance was set at .0022 on a 2.248-inch shaft, while the rods were set at .0019 on a 1.850-inch shaft. This team used a formula of just under .001-inch for every inch of shaft diameter on the main and just a hair over .001 for every inch of rod journal diameter.
What should the clearance be on a crankshaft rod?
Again, transfer the measurement from the crankshaft rod journal to the dial bore gauge and zero the dial indicator. Then check the clearance inside the rod bearing shell, measuring 90 degrees from the parting line.
RPM, crank stiffness/flex, power level, and BLOCK STRENGTH, are all more important to bearing clearances than if its car, boat or airplane. Bonzen, if your mains come in between .002 and .003, and your rods come in between .00175 and .00275, put the damn thing together and run it.
How does rod side clearance affect load capacity?
Note how bearing clearance has a major effect on load capacity, oil temperature, and oil flow. Increasing clearance from 0.0015 to 0.003-inch nearly quadruples the amount of oil flow exiting the bearing. This fits right in with the now-common approach of reducing rod journal size to slow bearing speed.
What are the 302 clearances for Rod and main bearings?
You need to make sure everything’s alright. You may need a line hone or your crank turned or different bearings. physically the bearings look kinda of good. .003″ is still a lot of clearance. For performance, 1.5-2 is probably prefferable, as it is a bit looser than stock specs, and yet isn’t really loose.
EngineLabs has seen a build book for an engine that ran six years ago, and the main clearance was set at .0022 on a 2.248-inch shaft, while the rods were set at .0019 on a 1.850-inch shaft. This team used a formula of just under .001-inch for every inch of shaft diameter on the main and just a hair over .001 for every inch of rod journal diameter.