LS Front Drive offset

Which LS offset is for me?

Through the LS models minor differences were made to the block, but the main difference is the front drive offset between the LS1 and LS2/3.

When you are ordering from us, it is important to make sure the right part is selected to suit your front drive offset. We divide our parts on this site up into 2 categories: LS1 offset and LS2/LS3 LSA offset.

How can i tell which offset my engine has?

If your engine is already in your car you may find the easiest way is to measure the distance from the front edge of the block to the front edge of the drive belt. If your engine is out of the car or you can access it easily, you can measure to the front of the balancer as shown in the photos below.

LS ENGINE TYPE	FRONT OF DRIVE BELT MEASUREMENT	FRONT OF BALANCER MEASUREMENT
LS1 Engine front drive offset	124mm	126mm
LS2 LS3 Engine front drive offset	100mm	105mm

LS1 Engine – front drive offset – Measure from the flat machined surface on the front of your engine block to either the front edge of your drive belt (124mm), or front of the balancer (126mm).

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LS2/LS3 Engine – front drive offset – Measure from the flat machined surface on the front of your engine block to either the front edge of your drive belt (100mm), or front of the balancer (105mm).

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Can I change my offset?

LS1, LS2 and LS3 balancers are interchangeable. LS2/LS3 offset can be used on LS1 to give more clearance from the radiator. Alternately an LS1 balancer can go on to an LS3 to bring the drive system forward. Example of this being an LS3 engine swap into a 58-64 Chevrolet works well with an LS1 offset as the alternator sits in front of the crossmember instead of fouling on it.

 

Alternator brackets: Note: Some 5.3L and 6.0L iron block LS Engines have no top outer hole for the mounting of our alternator brackets. The boss is there on the block but is not drilled or tapped. Some modifications to drill and tap this hole in the block may be required to fit ours or any alternator kit, please seek professional advice on this procedure.