Another chapter in our very popular LS1 How-To series, we take a look at the reluctor wheel located in the shortblock of your GEN III GM Engine. If you have any questions regarding the RPO or what the LS engine is, check our How-To Swap an LS1 Engine Guide, and our Guide to GM RPO’s
When you are swapping in your own LS engine, or building you own LS crate engine one of the many questions we receive are about the LS Reluctor Wheel, or the timing wheel.
This toothed wheel is located on your LS crankshaft and is often called the LS Reluctor Wheel, crankshaft position plate, or tone wheel. Pressed onto your crankshaft, the plate gives the crankshaft position sensor a true reading of where the crankshaft is in relation to the engine. This allows your PCM / ECU to operate your LS1 engine to optimum efficiency and power.
What sensors will I need to complete my LS1 swap?
The crankshaft position sensor, which is outlined in our LS1 sensor guide and LS1 engine swap checklist is located on the right side of your LS1 shortblock, while the LS Reluctor Wheel is located on the crank near the back of the block.
There are 2 versions of this LS Reluctor Wheel, with the 24 tooth version coming out of the LS1 and LS6 shortblocks. And the 58 tooth variation which is found in the LS2, LS3, LS9 and LS7 engine sets.
What do the terms LS, LQ, LM and numbers mean?
If you intend on running a MSD ignition box on your LS1 engine swap, you will need to make sure you have the right toothed LS Reluctor Wheel for your application, especially if you put your own engine together.
Whether or not you have a 24 tooth wheel or 58 tooth wheel will really determine what MSD box you will be running, make sure to purchase the correct unit. If you have any questions, please feel free to contact one of our ASE-certified sales associates for further details.
LS1 Firing Order
The firing order on your GEN III GM Engine is in the ignition order of 1-8-7-2-6-5-4-3. This firing order is slightly different than the popular GEN 1 and GEN II small block / big block Chevy order of 1-8-4-3-6-5-7-2. Keep this in mind when connecting your spark plugs to your coils and your wires.
This firing order swap is done through the GEN III Camshaft and the subsequent layout of the lobes that are much more different than earlier generations of the Chevy small block. The LS1, LS6 firing order is unique to the GEN III GM shortblock and much more different than any of the earlier versions of the Chevy firing order.
Only LS camshafts may be used in LS shortblocks, and LS1, LS2 GM ignition coils remain one of the most popular ignition upgrades for turbocharged inline six cylinder applications.
LS1 Crankshaft Differences
All GEN III LS cranks feature a 2.65″ main journal and 2.100″ rod journals, and all use the same rear main seal. All OE cranks are iron, except for the LS7 and LS9, which originally are fitted with forged steel cranks. Also, the LS7 features a 4.00″ stroke. Others feature a 3.62″ stroke.
This concludes our LS Reluctor Wheel article and we hope it sheds some light on your build. If you have any questions or comments leave them below.