What do i need to support 4:10's for 93 LX

83GTMUSTANG has a good point...4.10s for your every day driver might tach a little high on the freeway. You may want to consider getting 3.73...or the fairly new 3.90s. The 3.90s are a little more difficult to find...but they are out there. I've spoke with several people on message boards that have recently had 3.90s installed and love them. It doesn't sound like Sierra is completely ready to get new heads, manifold & cam...but if that is something you might be considering in the new future Sierra...I have a Edelbrock Performer 5.0 manifold (fuel injected, obviously) for sale in the classifieds section of this site. The manifold is in excellent condition. I'll part with it for $300 + shipping costs. I even have a 1/2" carbon fiber plenum spacer that goes between the upper & lower manifolds that I'll include in the deal. It gives the runners a little more length and made a noticeable difference in helping my motor run cooler. PM me if you're at all interested.