Do you have a MSD system in your car?If not,you can,t use it!If you have an MSD system,it has rpm limit pills that you can change.The MSD system saves your engine from over-revving,also gives out multi-spark!Example..reving to 5000rpm in first gear,if you rev over this it will cut out certain cyl. and let you know to backoff.Therefore saving you from overrevving and spinning bearings or other engine damage.Not the best explanation,but I hope you,ve learned it,s use?
