What kind of flywheels do odd fire engines use?
Flywheels for 225 and 231 odd fire engines will interchange. The 225’s have heavy flywheels (about 50 pounds) and have special balance characteristics for the odd fire engine. 225 Flywheels are drilled for 10-1/2″ clutch when this engine was used as an optional engine in 1966-71 CJ5/CJ6.
Why is the Buick 90 degree V6 called an odd fire?
Because the V6 was essentially a shortened V8, the engine had a unique odd-fire design – so called because of the unevenly spaced (at 90-150-90-etc.) firing impulses of this engine. This is the source of the characteristic and well-liked rumble.
When was the Buick 231 converted to even fire?
In mid-1977 the 231 was converted to “even-fire” (120 degree spaced firing impulses) by changing the crankshaft, camshaft, distributor and (presumably for increased volumetric efficiency) the cylinder heads and intake manifold. As such, interchange of these parts with earlier V6’s ranges from problematic to impossible.
What’s the firing order on an odd fire V6?
The cylinder numbering for the odd-fire V6 is 1-3-5 from the front down the driver’s side, and 2-4-6 down the passenger side.* The firing order is 1-6-5-4-3-2.
Flywheels for 225 and 231 odd fire engines will interchange. The 225’s have heavy flywheels (about 50 pounds) and have special balance characteristics for the odd fire engine. 225 Flywheels are drilled for 10-1/2″ clutch when this engine was used as an optional engine in 1966-71 CJ5/CJ6.
How does an odd fire engine engine work?
The ODD-FIRE Buick fires at odd interveils of 90 degrees then waits 150 degrees (crankturn) to fire again/ then fires at another 90 degrees/then at another 150 degrees. An even-fire engine fires at even 120 degree interveils. that is 120/120/120/120/120/120.
Because the V6 was essentially a shortened V8, the engine had a unique odd-fire design – so called because of the unevenly spaced (at 90-150-90-etc.) firing impulses of this engine. This is the source of the characteristic and well-liked rumble.