The main cause of that is when valve body, governor, and axle ratio arent matched set.I dont know who your builder is but I will say this,our kit does little or nothing to change the point in the rpm range or throttle position that your shifts take place.It only affects the way the shift feels and how long it takes from start to finish.I am certain there is a slight ,possibly immesuarable difference that raisingline pressure has on shift timing. However because tv limit controls plunger feed and the resultant mtv up oil to a fixed pressure it is nothing here .Although governor feed is off of the forward clutch or drive oil,a direct reult of line pressure in its varying pressure direct from the manual valve, ,the orificing into the governor feed portion of the circuit makes it less sensitive to increased line pressure.Malfunctions or leaks in valve body casting may be the cause when this is experienced in matched combinations .Increased line can result into crossleaks if valve body isnt torqued down or if increased pressure cause leaks into adjoining passages .I have seen many leaky casting cup plugs caused all different types of issues as well.I believe that I have the best finctioning 2004r recalibration kit availablee for the 2004r and sales of more than 200 a year are a testament to the absolute success of the product that wouldnt be worth anything without the use of the new seperator plate.Most builders have adapted our methods of hydraulic alibrations for a reason,they work.