Renix 4.0

My MJ 88 4x4 with the Renix 4.0 and 30" tires have not the power I saw in others the same model. The engine took to much time to rev as is the timing was not enough in advance. I have a cracked exhaust and a closed EGR valve. Cone filter did someting and maybe the flowmaster 40 deltaflow, but isn't enough. Can be the cracked exhaust the problem or the tires size? Maybe something else?

huh what?

The first thing to check is that both vehicles have the same gear ratios. They varied within the same year. It just depends on how it was ordered. If you can get the VIN# on both rigs, you can most likely get a build sheet and look it up, or the alternative, heaven forbid, is that you push yourself away from the keyboard, crawl under both and get dirty. :laugh3: The ratio is normally on a tag on one of the dif cover bolts.