Sounds like you need a re-gear. My 2.5L is the same way. With 33 inch tires and stock gears, it tops out about 55 and it's slow to go anywhere. As soon as I swap to 4.88 gears, should help the speed issues.
Denis A. Baldwin
1991 YJ 99 Vortec 5.7L, SM465, NP205, 14 Bolt Rear, Dana 60 Front, 5.13 Gears, Detroit Lockers, 395/85R20 46" Michelin XML tires on 20" XD Wheels, Cherokee Offset Springs (10" front to back stretch total), Bilstein 5150s, 1in. BL, custom cage, Warn M8000, Double D Dash/OHC, 4Low Front Stinger Bumper, DirtWorx Rear Bumper WTC, Tube Fenders, Comp Cut, 1 Ton HD Kingpin High Steering and PAID FOR.
2.5" on the suspension, 1" on the shackles, 2" on the body, 4.88 Superior Gears, 35" Goodyear MT/R with Kevlar, MSD-6 Offroad ignition box, Flowmaster Exhaust, Warn 9.5Ti Winch, Detroit Tru-Trac Front, Detroit Locker Back
"She may not look like much, but she's got it where it counts, kid. I've made a lot of special modifications myself." -Han Solo
Went to visit a friend at a mech shop. He put on a timing light and found she was severely retarding. Said the pcm was getting confused because of the time. We set the dist gear ahead by a couple of teeth and the timing was perfect, with a nice advance on throttle.
Found a secondary problem too. The MAP sensor wasn't getting any vacuum. We bypassed it straight to an intake vac port and now she purrs like a kitten, steady too.
He warned me, though. Said the MAP sensor reads the vacuum from "somewhere". We would've chased it down but he had to close shop.
I did a quick follow on the vac line that runs to the MAP. All I could gather in a short time was that it seemed to come from under the jeep along the tranny.
Can anyone tell me where the MAP sensor line comes from? There was no vacuum on it, although there should have been.
The people should never be scared of the government. The government should be scared of the people.