Converter, as others have mentioned, is likely miles off. IMO, horrible selection for what you have. What size is it, an 8"?
New converters aren't and shouldn't be comparable to 80-90's units that slip like crazy on cruise. Plenty of new converters will flash to 3800-4000 and run tight when under light loads. Many run tighter on cruise than cheapy lower stall units. A 9.5" unit that is well built will get you in the right area.
IQ is on as well, the cam should be done around 5600ish, so the flash speed is a bit close to peak HP.
7000 with a 26" tire and 4.10 gears, I get ~20% slip... THAT'S FRICKEN HORRIBLE!!!