BS In a 6bolt 2.3

[talon_42o]

Is it possible to keep the BS in a built 6bolt 2.3 stroker. I did some searching and didn't get a straight answer.

 

[Anger890]

Why would you want to keep the BS in your engine? If the engine is balanced properly and using a good Harmonic Blancer I don't see any issues with eliminating the 9 lbs of weight and a potential failure point.

 

[TunaTalon]

Engine balance has no effect on the need for balance shafts. The purpose of the balance shafts is to cancel the second order harmonics that are inherent with four cylinder in-line engines. In-line fours like the 4G63 engine have two pairs of pistons 180 degrees apart on the crankshaft. One pair goes up while the other pair goes down. If the speeds and acceleration rates of the two pairs of pistons were the same, the engine would be perfectly balanced. However, because the rod angle changes, the velocity of the piston changes throughout the stroke. The imbalance is due to the difference in velocity and is at twice the frequency of the RPM.

Balance shafts are a possible point of failure. If they are retained in a high mileage motor the bearings should be replaced.

My 2.3L stroker has balance shafts with new OEM bearings, but it is a seven bolt.

 

[Anger890]

Engine balance has no effect on the need for balance shafts. The purpose of the balance shafts is to cancel the second order harmonics that are inherent with four cylinder in-line engines. In-line fours like the 4G63 engine have two pairs of pistons 180 degrees apart on the crankshaft. One pair goes up while the other pair goes down. If the speeds and acceleration rates of the two pairs of pistons were the same, the engine would be perfectly balanced. However, because the rod angle changes, the velocity of the piston changes throughout the stroke. The imbalance is due to the difference in velocity and is at twice the frequency of the RPM.

Balance shafts are a possible point of failure. If they are retained in a high mileage motor the bearings should be replaced.

My 2.3L stroker has balance shafts with new OEM bearings, but it is a seven bolt.

Yes, I understand that. Did you use the 2.0 balance shafts in your engine? I ask as the mass of the shafts and harmonics between the 2 engines are different, mitsu had different part numbers for the balance shafts in the 2.4l engines. Which is also why I pointed out using a quality balancer. A good friend has a 2.4, no balance shaft, completley balanced with the ATI damper. Start it up next to a stock 2.0 and the 2.4 actually runs much smoother than the 2.0 with Balance shafts.

 

[92AWDHX40]

Got mine out, why would you still want them, the engine isnt stock its a stroker now, iw woulnt want stuff breaking.

 

[TunaTalon]

The ATI damper spins at base RPM and cannot by any stretch of math balance the second order harmonics which are at RPM times two. Please see the HARMONIC BALANCE OF IN LINE FOURS section of http://www.kidzuku.com/StrokeOrNot.pdf.

The balance shafts in my 2.3L stroker are the original shafts. With the lower weights of the Eagle rods and Wiseco pistons the harmonic forces with the 100mm stroke are about the same as for the 2.0L with OEM parts. See Figure 19 of the StrokeOrNot document.

Seat of pants feel for smoothness is also affected by motor mounts. My Talon has Prothane mounts and is a little rough.