You can do it in one afternoon. Even if you have to drop the pan a couple times. The CZ vb/governor is a better option imo. Your combo and numbers look like you could gain a decent amount by shifting later. Like around 5300-5400. If your tires are MT 275 60-15 they arent 28" More like 27.25" measured. Id lock up a lot later than 80mph also. Id try it around 95-100mph. What rpm does it drop to on the 4900 shifts and what boost?
His early shifts down low are hurting the mph. Also locking to soon hurts the e.t. When he raises the shift point on the 1-2 and 2-3 his mph will go up and locking later will help it too. Also his boost is so low its hard to make any conclusions about the converter without more data at higher boost levels. Thats why i was asking what the rpm dropped to on the shifts when he shifted at 4900. If he ran the car hard at high 20's boost id be willing to bet he would get almost no drop on shifts shifting at 4900. Assuming he is running 275/60-15 MT DR's (which are slightly under 27.5in tall) his rpm crossing the traps is under 4550
. Locking at 90 mph pulls it down to about 3800-3900 . Way to low to get optimum performance. Id bet et would be the same or better unlocked at 20 psi even if he lost a little mph.
